Spatial distribution of climatic conditions from the Middle Eocene to Late Miocene based on palynoflora in Central, Eastern and Western Anatolia

Abstract

The continental climatic evolution of Anatolia has been reconstructed quantitatively for the last 45 million years using the coexistence approach. Although there were some regional effects, the Anatolian Cenozoic continental climate record correlated with the European climatic condition and the global oxygen isotope record from marine environments. From middle Eocene to late Miocene, continental warming in Anatolia was pronounced for inferred winter temperature and mean annual temperature as in Europe. Generally, the palaeoclimatic property of Anatolia resembles the European climatic changing and marine temperature changing based on the oxygen isotope record; however, climatic values of the terrestrial area in Anatolia are higher from Lutetian to Aquitanian and these values are lower than European values from Aquitanian to Tortonian. Correspondingly, Cenozoic climatic cooling in Anatolia is directly associated with an increase of seasonality, palaeogeographic position and terrestrial condition. Furthermore, mean annual precipitation values of Anatolia remained relatively stable during the Eocene–Oligocene; however, these values indicated changing throughout middle–late Miocene. Moreover, in this study, decline of abundance and variables for the mangrove and back mangrove palaeocommunities during the last 45 million years is recorded because of the decreasing of humidity, temperature and increasing of terrestrial condition.

Keywords:

• Middle–Late Eocene
• Oligocene
• Miocene
• Anatolia
• palaeoclimate

1. Introduction

Present climatic conditions are the key to understanding past climates. Climatic conditions can be explained firstly by atmospheric circulation and latitude. Today, Anatolia is situated in the Mediterranean macroclimatic region which is dominant in the west of the continents in subtropical zone (Erlat, 2010). The Mediterranean climate is characterized by the strong summer–winter contrast associated with pronounced seasonal cycles in most climatic variables (Erlat, 2010). During the period from October to May, mid-latitude cyclonic storms cause wet, windy and mild weather types over Anatolia, although in some winter seasons very cold and dry weather conditions occur. Particularly from May to September, mid-latitude cyclonic storms are generally weak and rare over the Mediterranean as a result of the strong high-pressure ridge extending from the Azores subtropical high northwards. In this period, continental tropical airstreams from the North African and Arabian deserts dominate, causing warm and dry conditions over Anatolia except in the Black Sea region and the continental north-eastern part of the Anatolian Peninsula. Weather conditions are more stable than during the winter. The spatial distribution of the climatic conditions over Anatolia has been controlled by physical and physico-geographical factors which are the altitude, orography and land–sea interactions (distance from the sea). Consequently, temperatures decrease from coastal belts to interior regions, in particular over the eastern and northeastern portions of the Anatolian Peninsula. Mean temperatures show a sharp decrease towards the interior and eastern parts of the country, where altitude is mostly over 1000 m. As temperatures, average precipitation amounts in Anatolia decrease from the coastal belts to continental interior in Anatolia. The highest precipitation totals are along the northern side of the Northern Anatolian Mountains and southern side of Western Taurus Mountains. Orographical forcing cause high amounts of precipitation over these areas (Erlat, 2010).

Today, some parameters (e.g. altitude, orography and land–sea interactions) cause climate change in Anatolia, and the same parameters have affected the palaeoclimate during the Cenozoic era. Temperature and precipitation changes of the Miocene have been interpreted in lots of studies (e.g. Akgün, Akay, & Erdoğan, 2002; Akgün, Kayseri, & Akkiraz, 2007; Akgün et al., 2013; Akkiraz, 2008; Akkiraz, Akgün, Utescher, Bruch & Mosbrugger, 2011; Akkiraz, Kayseri, & Akgün, 2008; Akkiraz et al., 2012; Kayseri, 2010; Kayseri & Akgün, 2009; Üçbaş, Akkiraz, & Akgün, 2012). However, palaeoclimatic change from the Eocene to late Miocene in Anatolia has been firstly given in this study and has been summarized using the coexistence approach (CA) method. This paper will therefore focus mainly on detailed analysis of temperature and precipitation parameters, including mean annual temperature (MAT), mean temperature of coldest and warmest months, the mean annual precipitation (MAP) and mean monthly precipitation of the driest, warmest and wettest months. Furthermore, factors affecting abundance and variations of the mangrove and back mangrove elements have been discussed from the Eocene to Miocene, take on the consideration of palaeogeography.

2. Materials and methods

Palaeoclimatic reconstructions of Anatolia are provided from the palynological data of the Eocene, Oligocene and Miocene. In total, 10 Eocene, 26 Oligocene (Rupelian and Chattian) and 72 Miocene (Aquitanian, Burdigalian, Langhian, Serravallian and Tortonian) floras have been selected (Table 1). Although temperature variables of some regions have been obtained from the published studies (Akgün et al., 2002, 2007, 2013; Akkiraz, 2008; Akkiraz et al., 2008, 2011, 2012; Kayseri & Akgün, 2009; Üçbaş et al., 2012), temperature variables of other regions and precipitation values of all regions (Akgün, 2002; Akgün & Akyol, 1987, 1999; Akgün, Kaya, Forsten, & Atalay, 2000; Akgün, Olgun, Kuşçu, Toprak, & Göncüoğlu, 1995; Akgün & Sözbilir, 2001; Akgün et al., 2007; Akyol, 1971, 1980; Batı, 1996; Benda, 1971; Derman, Akgün, & Derman, 2003a, 2003b; Gündoğan, Önal, & Depçi, 2005; Karayiğit, Akgün, Gayer, & Temel, 1999; Kayseri & Akgün, 2008; Kayseri, Akgün, Ilgar, Yurtsever, & Derman, 2006; Nakoman, 1966, 1968; Sancay, Batı, Işık, Kırıcı, & Akça, 2006) have been calculated in this study.

Table 1. Coexistence intervals of central Europe and Anatolia for the Eocene.

Palynofloras of Anatolia have been analyzed using the CA method introduced by Mosbrugger and Utescher (1997). The method is one of the nearest living relative techniques which are based on the assumption that the climatic requirements of Tertiary plant taxa are similar to those of their nearest living relatives (Bruch, Utescher, Mosburgger & NECLIME members, 2011). The best description of the palaeoclimatic situation under which the given fossil flora lived is obtained from the climatic parameters that are calculated by CA method. The CA values of European countries (Serbia, Ukraine, Germany, Armenia, Bulgaria, Spain, Portugal, Hungary, Austria, Romania, Slovakia, Czech Republic and Italy) have been obtained from published values (Akgün et al., 2007; Barrón et al., 2010; Bruch, Fauquette, & Bertini, 2002; Bruch & Gabrielyan, 2002; Bruch, Utescher, Mosbrugger, Gabrielyan, & Ivanov, 2006; Bruch, Utescher, Alcalde Olivares, Dolakova, & Mosbrugger, 2004; Bozukov, Utescher & Ivanov, 2009; Ivanov, Ashraf, Mosbrugger & Palamarev, 2002; Ivanov, Ashraf, Utescher, Mosbrugger & Slavomirova, 2007; Ivanov, Bozukov, & Koleva-Rekalova, 2007; Kayseri & Akgün, 2008; Kvaček, 2007; Mosbrugger & Utescher, 1997; Syabryaj, Utescher, Molchanoff, & Bruch, 2007; Uhl, Mosbrugger, Bruch, & Utescher, 2003; Utescher, Djordjevic-Milutinovic, Bruch, & Mosbrugger, 2007; Utescher, Erdei, François, & Mosbrugger, 2007; Utescher, Mosbrugger, Ivanov, & Dilcher, 2009). The application of the CA is facilitated by computer programs (CLIMSTAT) and the database which contains the NLRs of more than 3000 Cenozoic plant taxa (Utescher & Mosbrugger, 2013).

In this study, the climatic parameters discussed here are the MAT, mean temperature of coldest month (TCM), mean temperature of warmest month (TWM), the MAP, mean monthly precipitation of the warmest month (MPwarm), mean monthly precipitation of the driest month (MPdry), mean monthly precipitation of the wettest month (MPwet), the mean annual range of temperature (the temperature difference between the warmest and coldest months; MART = WMT − CMT) and the mean annual range of precipitation (the precipitation difference between the wettest and driest months; MARP = MPwet − MPdry) (Bruch et al., 2011; Mosbrugger, 1999; Mosbrugger & Utescher, 1997; Pross, Klotz, & Mosbrugger, 2000). The last three parameters (MART, MARP and MAP) provide detailed information on temperature and precipitation pattern and means of assessing continentality (Bruch et al., 2011). The maps of the reconstructed climate data were generated using the CorelDRAW program.

The groups of the mangrove, back mangrove, swamp and freshwater, lowland and riparian and montane palaeocommunities were used for the palaeovegetational interpretation in this study. However, these palaeocommunities in the oldest palynological studies of the Eocene and Oligocene (Akgün & Sözbilir, 2001; Akyol, 1971, 1980; Alişan & Gerhard, 1987; Batı, 1996; Benda, 1971; Ediger, Batı, & Alişan, 1990; Nakoman, 1996a;b, 1968) have not been grouped. According to palaeovegetational properties currently obtained from the published palynological studies (e.g. Akkiraz, Kayseri, & Akgün, 2008), palaeovegetational groups of these oldest studies were established.

3. Palaeoclimate and palaeovegetation

In this part, palaeoclimatic interpretation and palaeovegetational distribution in Anatolia from the early–middle Eocene to early-late Miocene are summarized taking into consideration the palynofloral data. Besides, palaeoclimatic changing of this time interval are evaluated by MAT, CMT, WMT and MAP values.

3.1. Early–late Eocene

In this study, 10 palynoflora of the Çorum-Bayat, Yozgat-eastern of Sorgun and western of Sorgun, Yozgat-Çiçekdağ, Çorum-Çeltek Formation, Çorum-Armutlu Formation, Çardak-Tokça (Armutalanı) and Burdur were used for the palaeovegetational and palaeoclimatic interpretation of the early–late Eocene (Akgün, 2002; Akgün et al., 2002; Akkiraz, 2008; Akyol, 1980; Alişan & Gerhard, 1987; Nakoman, 1996a).

Palynofloras of Yozgat were recorded by most of authors and the first definition was reported by Nakoman (1996a). According to the first data, palynoflora of the Lutetian defined from the eastern part of Yozgat–Sorgun was represented by the back mangrove (Monocolpopollenites tranquillus (Arecaceae; 1–3%), Leiotriletes adriennis (Acrostichum aureum; 1–3%)) and inland palaeocommunities, Nakoman (1996a). Palaeovegetation of the inland was commonly composed of the lowland and riparian (Juglandaceae, Castanea, Myricaceae, Anacardiaceae, Sapotaceae and Araliaceae) and swamp and freshwater (Polypodiaceae, Schizaeaceae, Taxodioideae and Selaginellaceae) palaeocommunities. The montana communities were represented by the Quercus and Fagaceae; however, gymnosperm pollen were not recorded in this community (Nakoman, 1996a). Despite existence of the brackish condition represented by the back mangrove elements, terrestrial condition was generally widespread in the early–middle Eocene. Furthermore, palaeoclimate was tropical, and also humidity was widespread in Yozgat–Sorgun region. This warm and humid palaeoclimatic condition is represented by high CA values (the MAT 13.6–21.7 °C, CMT 1.8–15.6 °C, WMT 23.6–28.1 °C and MAP 1122–1520 mm) (Figure 1; Table 1).

Figure 1. Climate evolution in the Cenozoic: symbols on the colour bars belong to average coexistence approach values (CMT, MAT, WMT and MAP) of Anatolia and black-white line indicates the climatic trend from the Eocene to late Miocene.

Two different plant palaeocommunities were defined in the western part of Yozgat–Çiçekdağ and Sorgun which belonged to delta and inland environments (Akgün et al., 2002). In the delta environment, mangrove and back mangrove palaeovegetations were widespread, while the swamp and freshwater (Polypodiaceae, Selaginellaceae, Taxodioideae, Cupressaceae, Sparganiaceae, Crudia and Nyssa), lowland and riparian (Juglandaceae, Betulaceae, Engelhardia, Fagaceae, Anacardiaceae and Icacinaceae) and montane (Pinus, Quercus, Castanea and Symplocaceae) forests were an occupied inland area during the early–middle Eocene in Yozgat–Sorgun. The mangrove palaeocommunity (>40%) was abundantly represented by the Spinizonocolpites group (Nypa), Psilatricolporites crassus (Pelliciera), Avicennia alba-type (Verbenaceae) and Diporites iszkaszentgyorgyi. Furthermore, the back mangrove palaeocommunity (1–10%) indicated brackish water conditions composed of the Milfordia hungarica (Restionaceae), Mauritiidites franciscoi (Mauritia), Proxapertites group (Araceae), Longapertites group (Arecaceae), Monocolpopollenites tranquillus (Arecaceae), Myrtaceidites mesonesus (Myrtaceae) and pteridophytic spore Leiotriletes adriennis (Acrostichum aureum). These nearshore palaeocommunities were grown under the humid and tropical climatic conditions represented by the MAT 24.8–25.0 °C, CMT 22.5–23.0 °C, WMT 27.3–27.7 °C and MAP 1003–1520 mm (Table 1). Besides, coexistence intervals of the inland area are also characterized by the MAT 16.5–18.8 °C, CMT 9.6–13.1 °C, WMT 27.3–27.7 °C and MAP 1003–1520 mm (Figure 1; Table 1).

Detailed palynofloral definition was recorded by Akgün et al. (2002) in the Yozgat–Çiçekdağ region (near the village of Arabınköy). Nearshore conditions were widespread in this region during the early–middle Eocene. Maritime palynoflora represented by the mangrove (different kinds of Nypa species like Spinizonocolpites bulbospinosus, S. prominatus and S. cf. baculatus, 1–5%), back mangrove (Ephedraceae, 1–5%; Cicatricosisporites dorogensis (Anemia/Mohria;0–1%) and Myrtaceidites mesonesus (Myrtaceae; 0–1%)) elements and dinoflagellate cysts (Homotryblium vallum, Homotryblium sp., Cordospheridium inodes, Operculodinium microtrianium, Phthanoperidinium amoenum, Spiniferites ramosus, Wetzeliella lunaris, Wilsonidium echinosuturatum, Batiacasphaera sp., Cleistosphaeridium, Impletosphaeridum, Areosphaeridium and Impagidium sp., 30–40%) was recorded (Akgün et al., 2002). Especially swamp and freshwater (Osmundaceae, Polypodiaceae, Gleicheniaceae, Taxodioideae, Cupressaceae and Nyssa) and lowland and riparian (Juglandaceae, Myricaceae, Engelhardia, Cyrillaceae, Corylaceae, Carya, Icacinaceae, Simaroubaceae, Sapotaceae, Sambucus, Tilia, Ulmus, Pterocarya, Castanea, Rhus and Ilex) vegetations were widespread inland areas during the early-middle Eocene in Yozgat–Çiçekdağ. The montane elements in the palynoflora were represented by Pinus, Fagaceae, Quercus and Symplocaceae. Besides, palaeocommunities of this region were distributed under the humid and tropical climatic conditions represented by the MAT 15.6–20.8 °C, CMT 5.0–13.3 °C, WMT 24.7–28.1 °C and MAP 1122–1321 mm (Figure 1; Table 1).

Detailed palynological study of the Armutlu and Çeltek Formations in Çorum–Amasya was carried out by Akgün (2002) and palynofloras of the middle–late Eocene were defined. The common palaeovegetation during deposition of the Çeltek Formation were swamp and freshwater and lowland and riparian vegetations. The swamp and freshwater elements consisted of Osmundaceae, Polypodiaceae, Selaginellaceae and Nyssa were abundantly observed in samples of Çeltek Formation. The lowland and riparian forest elements (Cycadaceae, Juglandaceae, Pterocarya, Alnus, Corylaceae, Ulmus, Cyrillaceae, Simaroubaceae, Araliaceae, Rhus, Castanea, Carya and Tilia) were also recorded in this palynoflora (Akgün, 2002). Middle altitude areas in Çorum–Amasya representing montane elements (Fagaceae and Quercus) were not widespread throughout the middle–late Eocene. Brackish condition was also emphasized because of the existence of the back mangrove elements (Longapertites (Arecaceae), Proxapertites (Araceae), Cicatricosisporites dorogensis (Anemia/Mohria; 0–1%) and Leiotriletes adriennis (Acrostichum aureum); 5–25%). Furthermore, tropical climatic condition is defined based on the palynoflora and is represented by the MAT 16.5–23.9 °C, CMT 7.7–12.2 °C, WMT 27.3–27.9 °C and MAP 1003–1520 mm (Figure 1; Table 1).

Palynovegetation of the Armutlu Formation in Çorum–Amasya affected marine influence in the middle–late Eocene. This effect caused that mangrove (Psilatricolpites crassus (Pelliciera), Avicennia alba and Avicennia marina (Verbenaceae), Spinizonocolpites group (Nypa); 10–25%), back mangrove (Longapertites (Arecaceae), Proxapertites (Araceae), Milfordia hungarica (Restionaceae), Myrtaceidites mesonesus (Myrtaceae; 0–1%), Cicatricosisporites dorogensis (Anemia/Mohria; 0–1%) and Leiotriletes adriennis (Acrostichum aureum) 10–25%) elements and dinoflagellate cysts (1–5%) were commonly distributed during that time. Besides, the most common palaeovegetational distribution was characterized by swamp and freshwater elements (Nyssa, Sparganiaceae, Cupressaceae, Taxodioideae, Polypodiaceae and Selaginellaceae) in terrestrial area. The lowland and riparian forest elements (e.g. Platanus/Salix, Juglandaceae, Myricaceae, Engelhardia, Platycarya, Corylaceae, Alnus, Celtis, Carya, Icacinaceae, Pterocarya, Rhus, Castanea, Araliaceae, Vitaceae, Sambucus, Rosaceae, Rutaceae, Sapotaceae and Poaceae) abundantly accompanied the swamp and freshwater plants. The montane elements (e.g. Pinus, Abies, Quercus and Fagaceae) were generally less in the Armutlu assemblage like Çeltek palynofloral content. The CA values of this formation are characterized by the MAT 16.5–23.1/24.8–25.0 °C, CMT 9.6–16.4/22.2–24.8 °C, WMT 27.3–27.9 °C and MAP 1003–1520 mm (Figure 1; Table 1) and moist tropical climatic condition is determined based on the palynoflora and numerical climatic values.

The Eocene palynoflora of Çorum–Bayat was defined by Akyol (1980) and this palynoflora was represented by less abundance of the back mangrove elements (Longapertites (Arecaceae; 0–1%), Proxapertites (Araceae; 1–2%), Leiotriletes adriennis (Acrostichum aureum; 5–10%), Cicatricosisporites dorogensis (Anemia/Mohria; 5–10%) and Palmae, 10–25%). Common palaeovegetation type was represented by the lowland and riparian forests in Çorum–Bayat during the early Eocene and freshwater-swamp palaeocommunities was accompanied to these forests (Akyol, 1980). In addition, palaeoclimate in Çorum–Bayat was tropical (the MAT 13.6–21.7 °C, CMT 1.8–15.6 °C, WMT 23.6–28.1 °C and MAP 1122–1574 mm) and humidity was also affected in the deposition of Eocene sediments in Çorum–Bayat (Figure 1; Table 1).

Palynoflora of the early–middle Eocene in Denizli–Armutalanı (Başçeşme Formation; western Anatolia) was represented by the abundance of the mangrove (<40; Psilatricolporites crassus (Pelliciera) and Nypa), back mangrove elements (5–10%; Psilamonocolpites sp., Mauritiidites franciscoi (Mauritia), Myrtaceidites mesonesus (Myrtaceae) and Leiotriletes adriennis (Acrostichum aureum)) and nearshore palynomorphs (1–4%; dinoflagellate species) (Akkiraz, Akgün, Örçen, Bruch, & Mosbrugger, 2006). The presence of Sparganiaceae, Pediastrum spp. and Aglaoreidia cyclops in samples of Armutalanı may be indicated the existence of the fresh-water palaeocommunity. The lowland and riparian elements such as Juglandaceae, Betulaceae, Engelhardia and Fagaceae were abundantly recorded in the early–middle Eocene palynoflora and montane elements were represented by Pinus, Abies, Picea, Cathaya, Quercus and Castanea. Palaeoclimatic conditions during the early–middle Eocene in Denizli–Armutalanı were humid and tropical based on the abundance of thermophilous species and this climatic condition are represented by high coexistence interval (the MAT 17.0–21.1 °C, CMT 6.2–13.6 °C, WMT 26.5–28.1 °C and MAP 1146–1322 mm) (Figure 1; Table 1).

The other early–middle Eocene sediments in western Anatolia are located in the Burdur region (Varsakyayla Formation) and palynoflora of this region was represented by the less abundance of the mangrove (1–2%; Psilatricolporites crassus (Pelliciera)), back mangrove (1%; Arecipites brandenburgensis, Arecaceae) and nearshore palynomorphs (1–2%; Cordosphaeridium, Cleistosphaeridium and undifferentiated dinoflagellate cysts) (Akkiraz, 2008). The lowland and riparian and swamp and freshwater palaeocommunities composed of Engelhardia, Oleaceae, Cyrillaceae Myricaceae, Ulmus, Mastixiaceae, Carya, Anacardiaceae, Sapotaceae, Castanea and Nyssa were defined in the Burdur region (Akkiraz, 2008). The montane elements were mainly represented by Pinus, Fagaceae and Quercus. Furthermore, moist and tropical climatic conditions could be wide spread during the early–middle Eocene in the Burdur region and numerical climatic values of this region are the MAT 15.7–18.8 °C, CMT 9.6–13.1 °C, WMT 24.7–27.7 °C and MAP 823–1613 mm (Figure 1; Table 1).

The Eocene in Northern Thrace Basin was represented by various and abundant nearshore dinoflagellate species (e.g. Fibradinium annetorpense, Paleocystodinium golzowense, Deflandrea heterophlycta, D. oebisfeldensis, D. granulosa, Phelodinium magnificum, Homotryblium pallidum and Wetzeliella meckelfeldensis) and sporomorphs (e.g. Cicatricosisporites dorogensis (Anemia/Mohria; 10–15%), Davaliaceae and Quercus) (Alişan & Gerhard, 1987).

The warm climatic conditions and also humidity were widespread during the early–middle Eocene in Anatolia. The richest mangrove and back mangrove palaeocommunities are observed in all regions of this time because of these warm and humid climatic conditions and strong marine influence. Furthermore, numerical climatic values of all localities in Anatolia are almost similar, and two intervals are calculated in some regions due to the two different palaeoenvironments which are nearshore brackish and terrestrial environments. The average CMT values of terrestrial areas in Anatolia throughout the early–middle Eocene are between 11 and 12 °C indicated subtropical palaeoclimatic condition, and these values of the brackish swamp are 22–24 °C represented tropical or almost tropical palaeoclimate (Figures 1 and 2). The average MAT values are ~18 and 25 °C and the WMT value 27 °C. The MAP values are between 1200 and 1300 mm and these high precipitation values indicates the humidity in Anatolia during the early–middle Eocene (Figures 1 and 2). Strong humidity and tropical climate caused the widespread mangrove palaeocommunities near the coast and freshwater and swamp palaeovegetation inland areas. Scarcely abundance of the montane elements of palynofloras in Anatolia could be interpreted that palaeotopography could not be high during the early–middle Eocene (Figures 1 and 2). Furthermore, the CA results (MAT, CMT and WMT) of Europe and results of the inland area in Anatolia are similar in the Eocene (Popov et al., 2004). However, various European Eocene sites yielded lower temperatures when compared to approximate coeval coastal associations from Anatolia (Mosbrugger, Utescher & Dilcher, 2005). Additionally, the high precipitation values of Europe indicate the moist condition in the climate and these values higher than the Turkish records (Figure 2). Besides, high climatic values of this time are illustrated to the presences of the Early Eocene Climatic Optimum (Zachos, Pagani, Sloan, Thomas, & Billups, 2001).

Figure 2. Climate evolution in the Cenozoic: Continental CMT, MAT, WMT and MAP records for North Germany and global oxygen isotope record from Zachos et al. (2001). The original record from Mosbrugger et al. (2005) is shown in grey, calibrated data are in colour (green, blues and purple) (WB: Weisselster Basin; LRB: Lower Rhine Basin in Germany). Red-white line indicates the climatic trend from the Eocene to late Miocene of Anatolia.

3.2. Latest Eocene–early Oligocene

In this study, two palynofloras of the Sivas–Tuzhisar Formation and Mersin–Mut have been used for the palaeovegetational and palaeoclimatic interpretation of the latest Eocene–earliest Oligocene (Akgün, 2002; Kayseri et al., 2006). Furthermore, palynofloras of Çanakkale–Şevketiye (Danişment Formation), Çanakkale–Kuzu harbor, Isparta–İncesu, Erzurum/Çirişlitepe–Muş/Keledeşdere, Ebulbahar, İstanbul–Şile, Çorum–Osmanoğlu and Milas–Kultak have used palaeovegetational and palaeoclimatic interpretations of the early Oligocene (Akgün, 2002; Akgün et al., 2013; Akkiraz, Akgün, & Örçen, 2011; Akyol, 1971; Alişan & Gerhard, 1987; Batı & Sancay, 2007; Gündoğan et al., 2005; İslamoğlu et al., 2010; Kayseri, 2010; Kayseri-Özer, 2011; Kayseri et al., 2006; Sancay, 2005; Sancay et al., 2006).

The palynoflora of the latest Eocene–earliest Oligocene was derived from the Tuzhisar Formation in Sivas (Gündoğan et al., 2005; Kayseri-Özer, 2011). Three types of vegetation were recognized inland during this time interval and these types were swamp (Taxodioideae, Osmundaceae, Schizaeaceae, Urticaceae and Chenopodiaceae), riparian (Selaginellaceae, Cyrillaceae, Oleaceae, Sapotaceae, Juglandaceae, Carya, Ulmus, Anacardiaceae, Castanea and Simaroubaceae) and upland and lowland forests (Pinus, Quercus). Furthermore, abundance of the dinoflagellate species (37%; Thalassiphora cf. patula, Cribroperidinium sp. Homotryblium plectilum, Deflandera phosphoritica and Deflandera spp.) and rare back-mangrove element (1–2%; Acaciapollenites myriosporites (Acacia) and Ephedraceae) were defined in Sivas palynoflora. Palynological evidence suggested a humid and subtropical climate during the deposition of Tuzhisar Formation and the CA values are the MAT 15.6–18.8 °C, CMT 5.0–13.1 °C, WMT 24.7–27.7 °C and MAP 1122–1741 mm (Figure 1; Table 2).

Table 2. Coexistence intervals of central Europe and Anatolia for the early–middle Oligocene.

The other palynoflora of the Eocene–Oligocene boundary have been recognized from Mersin–Mut (S. Anatolia) and were represented by species of the swamp (Taxodioideae Cyrillaceae, Myrica, Selaginellaceae, Polypodiaceae, Schizaeaceae-Lygodium, Aquifoliaceae-Ilex), riparian (Eleagnaceae, Carya, Myrica and Alnus) and lowland (Engelhardia, Pinus, Icacinaceae, Ulmus, Quercus, Sapotaceae, Oleaceae and Eleagnaceae) palaeocommunities. Besides, mangrove (Spinizonocolpites (Nypa); 2–3%), back mangrove (Arecipites spp., Monocolpopollenites tranquillus (Arecaceae) and (Ephedraceae); 2%) and especially nearshore palynomorphs (Cleistosphaeridium, Cordosphaeridium, Hystrichokolpoma, Impagidinium, Lingulodonium, Nematosphaeridium, Operculadinium, Pentadinium, Thalissiphora and Spiniferites; 45–55%) were recorded in this palynoflora (Kayseri et al., 2006). In the latest Eocene–earliest Oligocene of the Mut basin, the climatic conditions indicated by the fossil palynomorphs record should be characterized as humid subtropical. The CA results which are the MAT 15.6–17.4 °C, CMT 7.7–8.3 °C, WMT 24.7–27.0 °C and MAP 1122–1151 mm support this palaeoclimatic interpretation (Figure 1; Table 2).

Although marine influence, which is recorded by the foraminifera, dinoflagellate species and mangrove elements, has continued from the early–middle Eocene to earliest Oligocene, the average palaeoclimatic value of the CMT has decreased at about 3 °C in terrestrial areas (Figure 1). This decline is also observed in other CA values (the MAT and WMT). Thus, palaeoclimatic cooling in Anatolia from the Eocene to Oligocene recorded by the coexistence intervals could be related to the Oligocene glaciations (Oi-1 Glaciations; Prothero, Ivany, & Nesbitt, 2003; Zachos et al., 2001) like palaeoclimatic conditions of Europe during this time interval (Figures 1 and 2). Additionally, variation and abundance of the mangrove and back mangrove elements has also decreased in this time interval because of changing climatic and/or environmental conditions.

Akgün (2002) studied the early Oligocene palynoflora of Osmanoğlu Formation in the Çankırı–Çorum basin (Amasya–Yakacık and Hırka regions) and this palynoflora was only represented by terrestrial sporomorphs. Angiospermous pollen was predominantly recorded in the Osmanoğlu palynoflora, while the gymnospermous pollen represented by Pinus, Sequoia and Taxodium was very rare (except for Cupressaceae, 21%). The angiospermous pollen were characterized by genera like Sparganiaceae, Myricaceae, Engelhardia, Carya, Pterocarya, Carpinus, Juglandaceae, Ulmaceae, Tilia, Sterculiaceae, Onagraceae, Betula, Quercus, Platanus-Salix, Loranthaceae, Elaeagnaceae, Castanea, Anacardiaceae, Cyrillaceae, Simaraubaceae and Oleaceae. According to the Akgün (2002), particularly the presence of tropical-subtropical Pinus, Sparganiaceae, Taxodium, Myricaceae, Cyrillaceae, Simaraoubaceae, Anacardiaceae, Myrtaceae, Castanea, Platanus/Salix, temperate Cupressaceae, Oleaceae, Ulmus, Carpinus, Quercus and cool Betula indicated a subtropical climate during the early Oligocene in the Çankırı–Çorum basin. This climatic condition is represented by the MAT 17.2–18.8 °C, CMT 5.5–13.1 °C, WMT 27.3–27.7 °C and MAP 1187–1355 mm (Figure 1; Table 2).

İslamoğlu et al. (2010) studied on the fauna and palynoflora of the early and late Oligocene from three locations in the NE and SW of the Thrace Basin. In the SW of the Thrace Basin, lignite-bearing units of the Danişmen Formation predominated and numerous lignite mines (Pullukçu, Pirincçeşme and Adnan Argan) were observed in this basin. Palynoflora of the Pullukçu mine (the Danişment Formation, late Rupelian) was defined and was rich in thermophilous plants such as Taxodium type, Myrica and Engelhardia. The presence of Avicennia (0–1%), a mangrove plant, in the Pullukçu section indicated the development of a mangrove on the coastal area, which was consistent with the occurrence of several indeterminate nearshore dinoflagellate cysts in the Pullukçu sample. Besides, the low diversity but extremely rich specimen Polymesoda-Tympanotonos assemblages were indicative of brackish-mangrove swamps. Palynospectra were rich in hygrophilous-riparian taxa (mainly Taxodium type, Myrica, Carya and Alnus) and also in aquatic herbs such as Sparganium-Typha, Liliaceae and Nyssa. According to İslamoğlu et al. (2010), palaeoclimate of the early Oligocene was a heritage of the tropical Eocene based on the presence of brackish-mangrove swamps.

The coal mine in NW Anatolia (Danişment Formation; Çanakkale-Şevketiye and Kuzu harbor) which was deposited in the same period (early Oligocene) with Pullukçu in the Thrace Basin was studied palynologically by Akgün et al. (2013). Palynofloras of the Pullukçu and Çanakkale were similar to each other and the most important similarity was the presence of the mangrove communities. Palynoflora of the Çanakkale–Şevketiye and Kuzu harbor contained abundant ferns, Castanea, back mangrove palaeocommunity (Longapertites proxopertitoides, L. psilatus, L. retipilatus (Arecaceae), Leiotriletes adriennis (Acrostichum aureum), Monocolpopollenites tranquillus (Arecaceae), Arecipites sp. (Arecaceae; range 0–8.7%), Disulcites kalewensis (Calamus), Myrtaceidites mesonesus (Myrtaceae) and Cicatricosisporites dorogensis (Anemia/Mohria); range 5.1–20%) and mangrove association comprising pollen of Psilatricolporites crassus (Pelliciera; range 29.8–63.7%), Spinizonocolpites sp. (Nypa; range 0–2%) (Akgün et al., 2013). A few poor preserved undifferentiated dinoflagellate cysts and microforaminiferal linings were also recorded. The great abundance of Pelliciera and scarcity of Nypa in Şevketiye samples suggest that the sediments certainly accumulated in a coastal swamp into which pteridophytic spores and angiosperms (e.g. Alnus, Ulmus, Carya, Platanus/Salix) were transported by river channels. The high percentages of mangrove elements indicated a transgression that could be related to a rising sea level during the Rupelian. Minor amounts of dinoflagellate cysts also occurred in the same phase as mangrove elements. The climatic condition designated by the fossil palynomorphs record should be characterized as humid subtropical in Çanakkale–Şevketiye and Kuzu harbor regions during the early Oligocene. The CA results of these regions which are the MAT 17.2–20.8 °C/21.7–23.9 °C/21.7–23.1 °C, CMT 7.7–13.3 °C/15.2–16.7 °C, WMT 27.7–27.9 °C and MAP 1215–1355 mm/1215–1613 mm support this palaeoclimatic interpretation (Figure 1; Table 2).

The early–middle Oligocene in the Northern Thrace Basin (Osmancık Formation) was generally characterized by various and abundant nearshore dinoflagellates species (e.g. Lejeunecysta fallax, Cordosphaeridium fibrospinosum, Hystricholkolpoma rigaudiae, Distatodinium ellipticum, D. craterum, Cleistosphaeridium sp., Wetzeliella ovalis and W. gochtii;>10%) and rare sporomorphs (e.g. Taxodioideae, Davaliaceae and Pinus) (Alişan & Gerhard, 1987).

The early Oligocene palynoflora of İstanbul–Şile was represented by the abundantly back mangrove elements (Monocolpopollenites tranquillus (Arecaceae), 1–2% and Disulcites kalewensis (Calamus) 22–25%) and less abundantly dinoflagellate species (1%) (Akyol, 1971). The common palaeovegetation type comprised of the lowland (Pinus, Castanea, Ulmus, Carya, Engelhardia, Cyrillaceae and Oleaceae) and swamp (Osmundaceae, Myricaceae, Taxodioideae, Polypodiaceae, Davaliaceae and Nyssa) forests. The palaeoclimate was subtropical and coexistence intervals represented this climatic condition are MAT 16.5–18.8 °C, CMT 4.8–13.1 °C, WMT 26.0–27.7 °C and MAP 1183–1520 mm (Figure 1; Table 2).

During the early Oligocene, palynofloral assemblage of the İncesu Formation in Burdur was represented by common swamp and freshwater vegetation (Polypodiaceae, Davaliaceae and Schizaeaceae) (Akkiraz et al., 2011). The lowland and riparian elements (Engelhardia and Carya) in this assemblage were abundantly recorded, whereas the montane elements (Pinus) were less abundantly observed. Percentages of dinoflagellate cysts (1%) and back mangrove (Leiotriletes adriennis (Acrostichum aureum), Longapertites group (Arecaceae), Ephedraceae and Disulcites kalewensis (Calamus), 2–3%) elements were low in the samples of İncesu Formation. The CA results are MAT 17.0–17.4 °C, CMT 6.2–8.3 °C and 9.6–13.3 °C, WMT 27.3–28.1 °C and MAP 1146–1151 mm and warm subtropical climatic condition were observed in Burdur during the early Oligocene (Figure 1; Table 2).

The palynoflora of the early Oligocene (Rupelian) was defined from the coal-bearing sediments in northwest and southwest of Muğla–Kultak (Kayseri, 2010). The palaeovegetation of this time was represented predominantly by evergreen and deciduous mixed and coniferous forests (Pinus, Cupressaceae, Castanea, Cyrillaceae, Ilex, Fagaceae, Quercus evergreen and deciduous, Carya, Symplocaceae, Oleaceae, Ulmus, Pterocarya, Sapotaceae and Betulaceae). Besides the swamp and riparian forests and aquatic vegetation plants represented by Myricaceae, Alnus, Simaroubaceae, Platanus/Salix, Acer, Anacardiaceae, Sapotaceae, Araliaceae, Mastixiaceae, Sparganiaceae, Taxodioideae, Osmundaceae, Selaginellaceae, Nyssa and Liliaceae were recorded in samples from Kultak. Mangrove and back-mangrove forest elements (Psilatricolporites crassus (Pelliciera; 5–25%), Avicennia (2–3%), Leiotriletes adriennis (Acrostichum aureum; 5%), Longapertites (Arecaceae; 1–2%), Arecaceae (1%) and Disulcites kalewensis (Calamus; 5–15%)) are defined in all samples and nearshore dinoflagellate species (1–2%) were accompanied less abundantly to these forest elements in this palynoflora. Herb and shrub vegetation plants (e.g. Poaceae) were recorded less abundantly. Decrease of the percentage of mangrove species throughout the sedimentary sequence in Kultak, presence of the dinoflagellate species in the upper part of the sequence, and increased marine influence in the Rupelian time during the sedimentation in Kultak have been interpreted by Kayseri (2010). This environmental result could indicate the transgression during the early Oligocene. The palaeoclimatic was warm subtropical and humidity was strong according to the CA results (MAT 16.5–21.3 °C/17.2–18.8 °C, CMT 7.7–13.3 °C/5.5–13.1 °C/6.2–13.1 °C, WMT 27.3–28.1 °C/27.3–27.7 °C and MAP 1122–1520 mm/1217–1520 mm/1217–1322 mm) (Figure 1; Table 2).

Sancay et al. (2006) and Batı and Sancay (2007) recorded in detail the palynofloral content of the early Oligocene from Erzurum/Çirişlitepe, Muş/Keledeşdere and Ebulbahar. Information from palynomorphs, nannoplankton, and foraminifera suggested that early Oligocene (Rupelian) sediments were deposited under brackish water, shallow and relatively deep marine conditions related to fluctuating sea level in the early Oligocene. Terrestrial areas in these regions were covered by the mixed mesophytic and freshwater and swamp forests (Pinus haploxylon and silvestris types, Araliaceae, Carya, Sapotaceae, Ulmus, Engelhardia, Gleicheniaceae, Polypodiaceae and Schizaeaceae). Besides, authors emphasized the abundance of the grassland species (Ephedraceae, Asteraceae-tubuliflorae and Apiaceae) and this abundance could be indicative of the presence of open vegetation areas in Erzurum and Muş during the early Oligocene. Plant distribution in the brackish swamp environment was represented by back mangrove elements (Leiotriletes adriennis (Acrostichum aureum; 6–20%), Disulcites kalewensis (Calamus; 2–6%)) and dinoflagellate species (20- > 100) (Sancay et al., 2006). Palaeoclimatic condition was subtropical during the early Oligocene in Erzurum and Muş and it was represented by the MAT 13.3–17.4 °C, CMT 1.7–8.3 °C, WMT 22.8–27.0 °C and MAP 1122–1151 mm (Figure 1; Table 2).

The marine influence observed in the beginning of the Oligocene has continued through the Oligocene. Because of this influence in the Rupelian, significant cooling of palaeoclimatic conditions has been observed in Anatolia based on the numerical climatic values. This palaeoclimatic cooling has continued in the terrestrial areas, while palaeoclimatic warming has been recorded on the coast. However, this warming condition in the coastal area defined by high CMT and MAT values is not like the Eocene because the maximum CMT and MAT values have been calculated in the Eocene samples. Besides, the lower climatic values of CMT (between 5 and 7.3 °C) have been observed from the Erzurum, Muş and Isparta-İncesu regions and also the higher MART values (20.5–19.9 °C) have been recorded in these regions (Figure 1; Table 2). Although all values were high in the Rupelian, the lower CMT and higher MART values of the Erzurum, Muş and Isparta regions could be related to the strong terrestrial condition. This terrestrial condition of these regions could be explained by the presence of Eastern Pontides and Taurus Highs in Eastern Anatolia (Popov et al., 2004). Besides, the MAP values did not change from Eocene to early Oligocene. Though presences of the mangrove and back mangrove elements have been recorded, abundance of these elements has declined from the Eocene to early Oligocene because of decreasing climatic values in Anatolia (e.g. CMT; from 22–23 °C to 16–17 °C) (Figure 1). During the early Oligocene, CMT values in Europe were lower than the values for inland and nearshore areas in Anatolia. However, MAT variables of terrestrial area, WMT and MAP values are similar to the climatic variables of Europe. This warm climatic condition could be related to marine influence in the early Oligocene, and widespread mangrove palaeocommunities in Anatolia support this environmental interpretation in this time (Figures 2 and 3).

Figure 3. Mangrove, back mangrove and marine palynomorphs abundance and distribution of Anatolia from the Eocene to Miocene.

3.3. Late Oligocene

Eleven palynofloras from Milas-Kultak, Çanakkale-Tayfur (Danişment Formation), Denizli-Kale-Tavas, İstanbul-Ağaçlı, Kars-Kömürlü, Erzurum-Çirişli/Kükürtlü, Muş, Thrace and Denizli-Çardak-Tokça were selected for the palaeovegetational and palaeoclimatic interpretation of the late Oligocene (e.g. Akgün & Sözbilir, 2001; Akgün et al., 2007, 2013; Akkiraz, 2008; Batı, 1996; Benda, 1971; Ediger et al., 1990; İslamoğlu et al., 2010; Kayseri, 2010; Nakoman, 1996b, 1968; Sancay, 2005, Sancay et al., 2006).

Late Oligocene (Chattian) palynofloras from different parts of the Thrace Basin were studied by many authors: Akyol (1964) “Arnavutköy, Küçükdoğanca, Büyükçekmece and İbrice”; Nakoman (1964, 1966b, 1967); Corsin and Nakoman (1967) “Keşan-Malkara, Kalivya-Yörük and Aliç-Türkobası-İbriktepe regions”; Benda (1971) “Edirne, Kırklareli, Tekirdağ and İstanbul”; Madler and Steffens (1979) “Edirne”; Ediger (1981a, 1981b), Ediger and Batı (1988); Ediger and Alişan (1989), Elsik, Ediger, and Batı (1990), Akyol and Akgün (1995) (Figure 1; Table 3). Different age assignments in these studies were made ranging from the early Oligocene to the early Miocene. Nevertheless, most of the recent palynological studies carried out directly on the Thrace Basin coals indicate that coal deposition in this basin was of the late Oligocene (Chattian) age (Batı, 1996; Ediger et al., 1990; Elsik et al., 1990). In the palynofloras of the Thrace Basin, Spinizonocolpites sp. (Nypa; 1%; Batı, 1996) of the mangrove elements was rare. Whereas Leiotriletes adriennis (Acrostichum aureum; 2–10%), Monocolpopollenites tranquillus (Arecaceae; 1–15%; Batı, 1996), Disulcites kalewensis (Calamus; 10–21%; Batı, 1996; Nakoman, 1964, 1996b, 1967) of the back mangrove elements and dinoflagellate species (1–10%) were observed abundantly in all palynofloras of the Thrace Basin. Especially, Disulcites kalewensis (Calamus) has been abundantly recorded in only Thrace Basin different from the other region in Anatolia and this abundance is characteristic of the late Oligocene palynoflora in this basin (Ediger et al., 1990; Nakoman, 1996b). Among defining taxa of the basin, the most frequent occurrences of montane types (Pinus haploxylon type, Podocarpus, Ulmus-Zelkova, Sequoia and Sapotaceae) indicated that the coal-forming depositional site was surrounded by a mountainous background on which these plants grew and their pollen grains were transported to the depositional site by long-distance wind and/or stream transport (Batı, 1996). Furthermore, relatively higher occurrences of Alnus, Schizaeaceae, Polypodiaceae, Anacardiaceae, Myricaceae, Taxodioideae, Cupressaceae, Osmundaceae, Pediastrum, Botryococcus and Sparganiaceae/Typhaceae and lower occurrences of Carya and Engelhardia indicated the presences of forests along the rivers and lakes in moist open areas. According to all authors who studied palynology of the Thrace Basin, coal seams were deposited in freshwater swamps that were beyond the marine influences and under subtropical climatic conditions (Batı, 1996). Also numerical climatic values are calculated from palynoflora of the Thrace Basin published by Batı (1996) and Nakoman (1996b) and these are similar with each other (MAT 13.3–21.3 °C/13.3–20.8 °C, CMT -0.1–13.3 °C, WMT 22.8–28.1 °C and MAP 1122–1520 mm/1122–1574 mm) (Figure 1; Table 3).

Table 3. Coexistence intervals of central Europe and Anatolia for the late Oligocene.

The late Oligocene basin fill in the NE of the Thrace Basin (Danişment Formation; the SE of Pınarhisar and NE of Tozaklı) was generally represented by siliciclastics and large lignite mine of the Danişment Formation (İslamoğlu et al., 2010). Palynoflora of the lower Chattian Tozaklı lignite (İslamoğlu et al., 2010) was represented by abundances of thermophilous plants (Taxodium type, Myrica and Engelhardia). Furthermore, there was an abundance of hygrophilous riparian taxa (mainly Taxodium type, Myrica, Carya and Alnus) that were accompanied by aquatic herbs such as Sparganium-Typha, Potamogeton, etc., in the pollen spectra of Tozaklı.

Akgün et al. (2013) defined palynoflora of the late Oligocene (early Chattian) coal-bearing clastic sediments from Çanakkale–Tayfur (Danişment Formation). Lignite-bearing deposits of Tayfur accumulated in a freshwater environment, as indicated by a majority of freshwater algae Pediastrum and the hydrophilous plant Sparganium (Sparganiapollenites neogenicus). Hygrophilous riparian taxa (e.g. Alnus, Carya) were abundant in the Tayfur palynoflora. The scarcity of coniferous pollen indicated that they might have lived outside the depositional area, probably indicating a distant mountain range. Mesophytic forest elements Quercus, Fagus, Carya, Ulmus, Betula, Zelkova, Engelhardia, etc. were recorded in low quantity in the pollen spectra. Grassland species such as Poaceae, Liliaceae, Ephedra and Chenopodiaceae were also minor components of the assemblage. The characteristic property of the late Oligocene palynofloras in NW Anatolia which is abundance of Calamus was also recorded from the Tayfur palynoflora (Akgün et al., 2013). According to the palynofloral records, palaeoclimatic conditions were condition was subtropical (MAT 16.5–21.3 °C, CMT 5.5–13.3 °C, WMT 27.3–27.9 °C) and humidity was widespread (MAP 887–1623 mm) in the terrestrial area during the late Oligocene (Figure 1; Table 3).

During the late Oligocene in Northern Thrace Basin, the upper part of Osmancık Formation and Danişment Formation was generally characterized by various spore and pollen species (e.g. Disulcites kalewensis (Calamus;>10%), Polypodiaceae, Schizaeaceae, Pinus spp., Alnus, Erdmanipollis pachysandroides, Sapotaceae and Carya), nonpollen palynomorphs (Pediastrum, Botryococcus and fungal spores) and rare dinoflagellate species (e.g. Cordosphaeridium gracile, Achomosphera alcicornu, Areosphaeridium arcuatum and Deflanderea phosphoritica) (Alişan & Gerhard, 1987).

In the İstanbul-Ağaçlı lignite, the dominant occurrence of Polypodiaceae, Pinus, Castanea, Engelhardia and lower frequencies of Quercus, Cyrillaceae, Nyssa, Schizaeaceae and Davaliaceae have been interpreted as latest Oligocene–early Miocene age (Nakoman, 1968). Back mangrove elements were observed less abundantly in the İstanbul-Ağaçlı palynospectra and these were represented by Disulcites kalewensis (Calamus; 3–10%) and Monocolpopollenites tranquillus (Arecaceae; 3%). According to the spores and pollen data, palaeoclimatic conditions could have been subtropical. Moreover, high values of the MAT, CMT, WMT and MAP support this climatic condition (MAT 16.5–21.3 °C, CMT 9.6–13.3 °C, WMT 26.0–27.9 °C and MAP 629–1520 mm) (Figure 1; Table 3).

Similar palynological data were obtained from three different areas (Çardak-Tokça, Kale and Tavas) in the Denizli region (Akgün & Sözbilir, 2001; Akkiraz, 2008; Benda, 1971). According to these data, palaeovegetation conditions in Denizli region were generally similar and were affected by marine influence during the late Oligocene (Chattian). The main component of the palynological assemblage of Denizli was the lowland and riparian elements (Engelhardia, Carya, Castanea; ~54%), which were represented by high percentages. Swamp and freshwater (Polypodiaceae, Osmundaceae, Taxodioideae and Chenopodiaceae; ~26%) and montane elements (Pinus silvestris and haploxylon types, Cedrus and Fagaceae; ~15%) were also dominant components of the assemblage. On the other hand, back mangrove elements (Disulcites kalewensis (Calamus; 3–20%), Leiotriletes adriennis (Acrostichum aureum; 2–10%), Longapertites (Arecaceae; 0–2%), Monocolpopollenites tranquillus (Arecaceae; 0–1%) and dinoflagellate cysts (0–1%) were characterized by minor amounts except for the Calamus and Acrostichum. The other minor elements consisted of palynomorphs such as Myricaceae, Salix and Sapotaceae. Palaeofloral distribution in the Denizli area indicates that subtropical climatic conditions were widespread during the late Oligocene and numerical climatic values support this condition. Coexistence intervals were obtained from the late Oligocene palynofloras (Chattian) of Denizli-Kale, Tavas and Tokça (Akgün & Sözbilir, 2001; Akkiraz, 2008; Benda, 1971). Climatic values of Denizli-Kale and Tavas are MAT 13.3–21.3 °C, CMT -0.1–13.3 °C, WMT 22.8–28.1 °C and MAP 1122–1520 mm (Akgün & Sözbilir, 2001), values of Çardak-Tokça are MAT 15.6–17.4 °C, CMT 8.0–8.3 °C, WMT 24.7–27.0 °C and MAP 1122–1151 mm (Akkiraz & Akgün, 2005) and values of Tokça are MAT 15.6–16.6 °C, CMT -0.1–7.0 °C, WMT 25.7–26.7 °C and MAP 979–1250 mm (Benda, 1971) (Figure 1; Table 3).

Milas-Ören (Alakilise and Kultak) is other late Oligocene locality in the SW Anatolia and spore and pollen content of this locality is defined by Kayseri (2010). According to the palynoflora, palaeovegetation of Ören was represented predominantly evergreen and deciduous mixed and coniferous forests during the Chattian (e.g. Pinus, Cathaya, Cupressaceae, Pterocarya, Ulmus, Carya, Engelhardia, Fagaceae, Quercus-evergreen and deciduous types, Cyrillaceae, Oleaceae, Tilia and Castanea). Distinctly differences from the early Oligocene, dinoflagellate species (Cleistosphaeridium sp. and Cordosphaeridium sp.) and microforaminiferal astar were defined and mangrove and back mangrove elements were not observed in the late Oligocene samples. Besides the swamp forest and aquatic vegetation, plants (e.g. Polypodiaceae, Davaliaceae, Osmundaceae, Schizaeaceae and Myricaceae) were less abundantly recorded in palynospectra of Ören. During the Chattian, the riparian forest elements were high. Moreover, herb and shrub vegetation plants were recorded less abundantly in the Chattian palynospectra of Ören. According to Kayseri (2010), there were humid and subtropical climatic conditions during the late Oligocene (Chattian) in the Ören region (SW Anatolia) based on the palynoflora evidences. Author emphasized that high coexistence value of this region supported humid and warm climatic condition (MAT 15.6–21.3 °C/17.0–21.3 °C, CMT 5.0–13.3 °C/6.2–13.3 °C, WMT 24.7–26.5 °C/27.3–28.3 °C and MAP 1122–1520 mm/1146–1322 mm) (Figure 1; Table 3).

Sancay et al. (2006) defined palynoflora of the late Oligocene from Kars-Kömürlü, Muş-Ebulbahar, Keledeşdere and Erzurum-Çirişli/Kükürtlü. According to palynomorphs, nannoplankton and foraminifera, late Oligocene (Chattian) sediments were deposited under brackish water, shallow and relatively deeper marine conditions related to fluctuating sea level in the Oligocene. Mixed mesophytic and freshwater-swamp forests (e.g. Pinus haploxylon type, Sparganiaceae, Ulmus, Engelhardia, Gleicheniaceae, Polypodiaceae and Schizaeaceae) were common in terrestrial areas. Furthermore, authors have underlined the abundance of grassland species (Poaceae, Ephedraceae, Chenopodiaceae, Dipsacaceae, Asteraceae-tubuliflorae and Apiaceae) as the early Oligocene and this abundance could have indicated the presence of open vegetation areas in Erzurum, Muş and Kars during the late Oligocene. Besides, plant distribution in the brackish swamp environment was represented by less abundance of back mangrove elements (Leiotriletes adriennis (Acrostichum aureum; 1–2%), and dinoflagellate species (20- > 100) (Sancay et al., 2006). Palaeoclimatic condition was subtropical represented by the MAT 13.3–17.4 °C, CMT -0.1–8.3 °C and WMT 22.8–27.0 °C during the early Oligocene in Kars, Erzurum and Muş region (Figure 1; Table 3). However, humidity in terrestrial areas of these regions was lower than the other late Oligocene localities, based on the precipitation values (MAP 1122–1151 mm).

According to the palynological data, palaeoclimatic values from the Rupelian to early Chattian have declined, and CMT values especially have decreased as much as ~3 °C in the terrestrial area. The lowest CMT values were recorded from the Kars, Erzurum and Muş regions as the early Oligocene because of the strong terrestrial condition (Ararat, Taurus highs and Eastern Pontides, (Popov et al., 2004)). Besides, high MART (20.8 °C) and low MAP warm values of these regions supported strong drought and terrestrial conditions during the late Oligocene. During the Chattian, an increase of CMT, MAT and WMT values has been observed and this increase could be correlated with the globally observed late Oligocene Warming (Figures 1 and 2). Additionally, distinct changes in the palaeoclimate and palaeogeography caused the abundance and variations of the mangrove and back mangrove elements. The mangrove element is represented only by Nypa (1%), while back mangrove elements are characterized by Acrostichum aureum, Calamus, Arecaceae and Longapertites. Besides, the most significant difference is the abundance of Calamus during the late Oligocene. In the Chattian, palaeoclimatic condition of Anatolia should be similar to Europe, based on the coexistence intervals (Figure 2).

3.4. Early Miocene (Aquitanian)

Nine palynofloras of Burdur (Kavak Formation), Burdur (Aksu Formation), Denizli-Kurbalık, Kale, Tavas regions and Muş (Keledeşdere and Ebulbahar) were used for the palaeovegetational and palaeoclimatic interpretation of the early Miocene (Aquitanian) (e.g. Akgün & Sözbilir, 2001; Akgün et al., 2007; Akkiraz, 2008; Benda, 1971; Sancay, 2005, Sancay et al., 2006).

Akgün et al. (2007) reconstructed the palaeoenvironment during the deposition of the Kavak Formation (Burdur) based on the palynological data of the Aquitanian. The ecological characteristics of species were grouped under generic headings, such as lowland and riparian (e.g. Engelhardia, Castanea, Myricaceae, Juglandaceae, Betulaceae), and swamp and freshwater elements (Schizaeaceae, Polypodiaceae, Taxodioideae). Montane elements were made up of high percentages of Pinus, Quercus and Fagaceae. Back mangrove elements Longapertites retipiliatus (Arecaceae; 0–1%), Myrtaceidites mesonesus (Myrtaceae; 0–1%) were described as individual grains. Besides, nearshore palynomorphs Cleistosphaeridium sp. and undifferentiated dinoflagellate cysts were scarcely recorded in the samples of Kavak Formation as well. During the Aquitanian, the palaeoclimate could be subtropical under high rainfall and high CA values support this climatic condition (MAT 16.5–20.8 °C, CMT 5.5–13.3 °C, WMT 27.3–28.1 °C and MAP 1122–1355 mm) (Figure 1; Table 4).

Table 4. Coexistence intervals of central Europe and Anatolia for the early Miocene (Aquitanian).

In the assemblage of the Aksu Formation (Burdur), the swamp and freshwater elements mainly constituted Taxodioideae (5%) and also Leiotriletes genera (Schizaeaceae) Polypodiaceae, Davaliaceae, Gleicheniaceae also occurred in the assemblage (Akgün et al., 2007; Akkiraz, 2008). Back mangrove elements were characterized by minor amounts (0–2%) of Leiotriletes adriennis (Acrostichum aureum) and Arecaceae. The lowland and riparian elements mainly consisted of high abundances of Engelhardia (17%) and Castanea (19%). Montane elements were characterized by a high percentage of Quercus. Besides, minor amount of shallow marine Cleistosphaeridium sp and undifferentiated dinoflagellate cysts was recorded (0–2%) in palynoflora of Aksu Formation. Palaeoclimatic conditions in Burdur during the Aquitanian could be subtropical and humidity was widespread, based on the palynological data and CA results (MAT 21.0–21.1 °C, CMT 9.6–13.3 °C, WMT 27.3–27.9 °C and MAP 1122–1355 mm) (Figure 1; Table 4).

The palynomorph assemblages of the early Aquitanian in western Anatolia were determined from the Denizli-Kurbalık and Kale (Akgün & Sözbilir, 2001; Akgün, Kayseri, & Akkiraz, 2004, Akgün et al., 2007; Benda, 1971). During the early Aquitanian, Castanea, Quercus, Ulmus and Carya were dominant as a mixed mesophytic forest. Moreover, Cyrillaceae, Engelhardia and Myricaceae, which belong to mixed mesophytic, swamp and riparian forests, were abundant in the early Aquitanian palynomorph assemblage. In addition, the species of the dinoflagellate cysts and back mangrove elements (e.g. Disulcites kalewensis (Calamus; 2%), Leiotriletes adriennis (Acrostichum aureum; 2%)) were found less frequently in this assemblage. According to the sporomorph content, palaeoclimatic conditions throughout the Aquitanian were subtropical (MAT 16.0–21.3 °C, CMT 9.6–13.3 °C, WMT 26.0–28.3 °C) and rainfall was high (MAP between 1122 and 1520 mm) (Figure 1; Table 4).

Sancay et al. (2006) obtained the detailed spores and pollen content of the early Miocene from Muş-Keledeşdere and Ebulbahar. According to sporomorph content, nannoplankton and foraminife content, sediments of the early Miocene (Aquitanian) were deposited under brackish, shallow and relatively deep marine conditions (Sancay et al., 2006). Terrestrial areas in Muş-Keledeşdere and Ebulbahar were covered by mixed mesophytic and freshwater and swamp forests (abundantly Pinus, Araliaceae, Carya, Ulmus, Engelhardia, Gleicheniaceae, Davaliaceae, Polypodiaceae and Schizaeaceae). Also abundance of the grassland species (Ephedraceae, Chenopodiaceae, Asteraceae-tubuliflorae, Poaceae and Apiaceae) was high and this abundance could interpret the presence of grassland areas in Muş during the early Miocene. Plant distribution in the brackish swamp environment was characterized by back mangrove elements (Leiotriletes adriennis (Acrostichum aureum; 1–2%), Disulcites kalewensis (Calamus; 1–2%)), Monocolpopollenites tranquillus (Arecaceae; 1–2%) and various dinoflagellate species (20- > 100) (Sancay et al., 2006). According to palynological data, palaeoclimatic conditions of terrestrial area in Muş were subtropical during the early Miocene (MAT 13.3–20.8 °C, CMT -0.1–1.1 °C, WMT 22.8–28.1 °C and MAP 1122–1595 mm), while this condition could be warm near the coast (MAT 13.3–20.8 °C, CMT 1.7–13.3 °C, WMT 22.8–28.1 °C and MAP 1122–1595 mm) (Figure 1; Table 4). Additionally, two obtained coexistence intervals for Muş region support the presence of different deposition area.

According to the palynological records from the Chattian to Aquitanian, the CMT values decrease with increasing MAT values (Figure 1) and palaeoclimatic cooling recorded based on the CA values of the CMT might be correlated with the Mi-1Glaciation (Prothero et al., 2003; Zachos et al., 2001). Besides, the other important event on climate has observed precipitation and rainfall has been significantly increased throughout the Chat-Aquitanian interval (Figure 1). The high MAP and MARP values have been calculated from the locations in western Anatolia (Denizli and Burdur) and sediments in these locations have been deposited under the marine influence during the Aquitanian (Figure 1; Table 4). Thus, marine effect may have caused high rainfall in western Anatolia (Popov et al., 2004) (Table 4). However, marine environment as well as strong terrestrial conditions have been determined in eastern Anatolia (Popov et al., 2004). For this reason, low precipitation ratio of the regions in Eastern Anatolia could be explained by this strong terrestrial, the Eastern Pontides. In addition, during the Aquitanian, palaeovegetation near the coast has been represented by low ratio of the back mangrove elements consisting of Acrostichum aureum, Calamus, Arecaceae, Myrtaceae and Longapertites and dinoflagellate species. Absence of the mangrove elements despite the presence of marine conditions and strong humidity could also be related to the low climatic values in the Aquitanian (Table 4). Moreover, decline of the palaeoclimatic values (e.g. CMT) of the Chat-Aquitanian in Europe was recorded in the values of Anatolia in same time interval. Similarity of climatic conditions between Europe and Anatolia in the Chattian has continued in the Aquitanian (Figure 2).

3.5. Early Miocene (Burdigalian)–middle Miocene (Langhian)

Coal-bearing sediments deposited during the Burdigalian and Langhian interval were commonly observed in Anatolia (Balıkesir-Bigadiç-Gönen, Samsun-Havza, Milas-Kultak-Hüssamlar-Karacaağaç, Çanakkale-Çan, Ankara-Beypazarı, Kocaçay and Cumaovası basins, İzmir-Tire, Kütahya-Seyitömer and Tunçbilek, Manisa-Soma, Sabuncubeli, Aydın-Kuloğulları-Başçayır and Muğla-Yatağan-Eskihisar, Bağyaka, Bayır areas) and most of them were studied palynologically (Akgün & Akyol, 1999; Akgün et al., 2007; Ediger et al., 1990; Güngör, 1991; Kayseri & Akgün, 2008; Kayseri, Akgün, & Örçen, 2007). Besides, palaeoclimatic properties of Anatolia for the Burdigalian–Langhian time interval have been evaluated using these defined palynoflora (e.g. (Akgün et al., 2007; Kayseri et al., 2007)). According to these palynological studies, palaeovegetation of all regions during this time interval was represented by thermophilous species (e.g. Engelhardia, Quercus-evergreen type, Cyrillaceae, Schizaeaceae), although there were differences of plant distribution in vegetation because of the orographic dissimilarities. Additionally, some pollen species (Ulmus, Podocarpus, Cathaya, Taxodioideae, Cupressaceae, Sparganiaceae, Myricaceae, Engelhardia, Carya, Platanus/Salix, Castanea, Cyrillaceae, Nyssa, Sapotaceae, Poaceae, Lemnaceae, Juglandaceae, Pterocarya, Simaroubaceae, Myrtaceae, Reveesia, Alnus, Carpinus and Fagaceae) were accompanied with these species. Besides, pollens of Avicennia, Acrostichum aureum and Calamus have been recorded from brackish sediments of the Langhian in Milas–Kultak and this evidence supports the warm climatic condition in western Anatolia.

The palaeoclimate is subtropical during the Aquitanian–Langhian interval. However, according to the CA method, temperature values increased from the Aquitanian (CMT: ~9 °C and MAT: ~19 °C) to late Burdigalian (CMT: ~10–11 °C and MAT: ~18 °C) (Figure 1; Tables 5 and 6), although there are no sufficiently palynological data from the Aquitanian to Burdigalian. This increase corresponds to the middle Miocene Climatic Optimum, which is also globally observed based on the isotopic, faunal and floral data (e.g. Mosbrugger et al., 2005; Zachos et al., 2001). In the Langhian, this warm climatic condition has continued to increase in the coastal environment (e.g. Milas-Kultak; MART: 14.9 °C) (Figure 1). However, temperature values in the terrestrial areas of the Langhian have decreased. Thus, palaeoclimatic trend in North Germany is not similar to the trend of Anatolia, although temperature values of Anatolia and North Germany are the same as each other (Figure 2). This different palaeoclimatic event in between Anatolia and North Germany could be related to observing of the marine influences in the different time interval (Figure 2). For example, marine influence observed throughout the early Miocene has been decreased in the Langhian, and also strong terrestrial conditions have been observed in Anatolia because of tectonic events (Popov et al., 2004). Furthermore, high precipitation values of the Aquitanian (MAP) decreased in the Burdigalian and this decline has increased in the Langhian again (Figure 1).

Table 5. Coexistence intervals of central Europe and Anatolia for the late early Miocene (Burdigalian).

Table 6. Coexistence intervals of central Europe and Anatolia for the early middle Miocene (Langhian).

3.6. Late-middle Miocene (Serravallian)–late Miocene (Tortonian)

The early and middle Serravallian palynomorph assemblages of Anatolia were determined from Aydın-Şahinali, İncirliova, Hasköy, Söke and Köşk areas in the Büyük Menderes Graben (Akgün & Akyol, 1999), Muğla-Yatağan (Atalay, 1980; Erdei, Yavuz, Akgün, & Hably, 2002; Sickenberg, 1975), Akhisar-Çıtak (Akgün & Akyol, 1987; Akgün et al., 2007; Göktaş & Ünay, 2000; Yağmurlu, 1984), İzmir-Kocaçay and İzmir-Cumaovası basins from western Anatolia (Kayseri-Özer, Sözbilir, & Akgün, 2014), Çorum (Kaymakçı, Özçelik, White, & Van Dijk, 2001; Kayseri & Akgün, 2008; Şen et al., 1998; Sümengen et al., 1990), Kırşehir-Avcıköy and Hacıbektaş (Akgün et al., 1995; Tekkaya, 1974), Konya-Ilgın (Akgün et al., 2007; Karayiğit et al., 1999), Yozgat-Çiçekdağ (Akgün et al., 2007; Kayseri & Akgün, 2008) from central Anatolia. According to these studies, the palaeoclimate was warm during the Serravallian–middle Tortonian interval.

The mixed mesophytic composed of Quercus, Castanea, Engelhardia, Oleaceae, Cyrillaceae and swamp forests (Myricaceae, Nyssa and Taxodioideae) was well developed during the early and middle Serravallian in western Anatolia. The riparian forest elements (e.g. Alnus, Carya, Salix and Ulmus) were also abundantly recorded in sporomorph assemblages in western Anatolia (e.g. Aydın-Hasköy and Köşk regions). The mountain forest elements have been observed in low percentages and high frequencies in all palynoflora. The species of open and freshwater vegetations such as Poaceae, Chenopodiaceae, Asteraceae, Umbelliferae, Sparganiaceae, and Myricaceae were frequently but less abundantly recorded in the sporomorph assemblage of the early–middle Serravallian of all regions.

The latest Serravallian–earliest Tortonian palynomorph assemblages were defined from Aydın-Köşk, Hasköy, Sarayköy (Akgün & Akyol, 1999), Muğla-Yatağan region (Atalay, 1980; Erdei et al., 2002; Sickenberg, 1975) in western Anatolia and Sivas-Gemerek (Vasıltepe) (Kayseri & Akgün, 2002; Langereis, Şen, Sümengen, & Ünay, 1990; Sümengen et al., 1990), Kırşehir-Tuzköy (Akgün et al., 1995) in central Anatolia. The palynoflora of the latest Serravallian–earliest Tortonian was represented by abundant swamp (Taxodioideae and Myricaceae) and mountain forest elements (Pinus haploxylon and P. silvestris types). The riparian and mixed mesophytic forest elements characterized by Alnus, Platanus/Salix, Quercus, Carya and Ulmus were predominated in the assemblage like the early–middle Serravallian. Abundance of the grassland species (Poaceae, Chenopodiaceae, Asteraceae and Umbelliferae) has been increased from the Serravallian to earliest Tortonian in the palynofloral assemblages of western and central Anatolia.

Palynofloras of the early and middle Tortonian were defined from Elazığ and Sivas-Hafik (Akgün et al., 2000, 2007) in central Anatolia. The early Tortonian palynoflora of samples was collected from Elazığ and it was characterized by the abundant mixed mesophytic and riparian forest elements (Ulmus, Quercus, Castanea, Alnus and Sambucus). Unlike the content of the Elazığ palynoflora, these forest elements were less frequently observed in Sivas-Hafik palynoflora. The swamp (Taxodioideae, Myricaceae) and mountain forest elements (Pinus haploxylon type) were represented by low percentages in two palynoflora of these regions. The value of the open vegetation communities increased from the early to the middle Tortonian and was characterized by the Poaceae, Asteraceae-tubuliflorae and liguliflorae, Umbelliferae and Chenopodiaceae.

The Burdigalian–Langhian interval is the warmest in the Miocene (e.g. Utescher et al., 2009; Zachos et al., 2001). This warming decrease and a tendency towards cooler conditions occurred in Serravallian and early Tortonian. For this reason, the abundance of thermophilous plants decreased in palynofloras of Europe and Anatolia (e.g. Akgün et al., 2007; Bessedik, 1985; Jiménez-Moreno, Fauquette, & Suc, 2010). Besides, mesothermic forest elements (mainly deciduous Quercus, Carya, Fagus etc.) and high-elevation conifers increased during the Serravallian–early Tortonian. This climatic cooling after the middle Miocene Climatic Optimum period, which was recorded on a worldwide scale by Miller, Wright, and Fairbanks (1991) and Zachos et al. (2001), caused palaeovegetational differentations and changes in temperatute values. The average MAT, WMT and CMT values are 15, 24 and 5 °C in the Serravallian, respectively, and these temperature intervals are lower than North Germany (Figures 1 and 2). The continued cooling from the Langhian to Serravallian was caused by a decrease in thermophilous species (e.g. Engelhardia, Sapotaceae, Schizaeaceae, Cyrillaceae) and an increase in mesophytic species (e.g. Carya, Ulmus, deciduous Quercus, species of Pinaceae family and Fagus) in palynoflora of Anatolia. The MAP values in the Serravallian are generally high and these highest values indicate the humidity. For this reason, the swampy (Myricaceae, Nyssa, Sparganiaceae and Taxodioideae) and wooded areas which are distributed in the lowland and high elevations in central and western Anatolia are widespread, based on the palynological data. The MAT and CMT values decreased throughout the Serravallian–earliest Tortonian, then values increased in the middle Tortonian (especially in central and eastern Anatolia). However, in the late Tortonian, MAT value has decreased again in the Central Anatolia (Tuğlu Formation of the Çankırı-Çorum Basin; Mazzini, Hudáčková, Joniak, Kováčová, Mikes, ... & Soulıé-Märsche., 2013). Also, the MAP values during this period indicate fluctuations like the MAT values (Figure 1). Although the lower boundary of the MAP values of early–late Tortonian is low (Tables 7 and 8), the humidity has increased from the Serravallian to middle Tortonian, while it has decreased in the late Tortonian in central Anatolia. Thus, the swampy area represented by Myricaceae and Taxodioideae was recorded in the middle Tortonian (Sivas-Hafik, Akgün et al., 2000) due to increasing humidity. The decline of the lower boundary of the MAP could interpret the drought condition of palaeoclimate time to time (seasonality). There is not observed by changing of the WMT values from the Serravallian to Tortonian except for the increasing of the WMT values in the middle Tortonian.

Table 7. Coexistence intervals of central Europe and Anatolia for the late middle Miocene (Serravallian).

Table 8. Coexistence intervals of central Europe and Anatolia for the early late Miocene (Tortonian).

4. Mangrove vegetation in Anatolia

In this study, spores and pollens of the mangrove and back-mangrove environments were recorded from the palynofloras of the Eocene, Rupelian, Chattian, Aquitanian and Langhian (Figures 3 and 4). It has further been observed that the distribution of the mangrove and back mangrove vegetations has been affected by climate, humidity and palaeogeographic position according to all palynological and CA results from Eocene to late Miocene. In the early–middle Eocene, the strongest humidity was observed along with the warmest climatic conditions (Early Eocene Climatic Optimum) (Zachos et al., 2001). For this reason, mangrove distribution must have been widespread in the Eocene, although this distribution has indicated differences from region to region in Anatolia (Akgün, 2002; Akgün et al., 2002; Akkiraz, 2008; Akyol, 1980; Alişan & Gerhard, 1987; Nakoman, 1996a). Furthermore, back mangrove and buttonwood elements are not subject to the same degree of tidal inundations as experienced by “true mangrove (white, black, red mangrove)” species growing near mangrove stands towards the landward side, and these elements are abundantly recorded in the palynoflora of early–middle Eocene (Figure 3). Additionally, rich and diverse dinoflagelate species have been also recorded in the Eocene palynoflora. From the Eocene to early Oligocene, abundance and diversity of mangrove and back mangrove elements decreased, presumably due to palaeoclimatic changing from tropical to subtropical and/or differentiation of palaeogeography of Anatolia in the Rupelian. Mangrove elements were represented by only Avicennia (black mangrove; %1–2) and Nypa, Pelliciera (buttonwood; ~50–65) (Figure 3). Back mangrove elements were characterized abundantly by Calamus, Acrostichum aureum, and also Arecaceae, Ephedraceae, Myrtaceae, Anemia/Mohria and Acacia were rarely accompanied by these pollens (Figure 3). The most important finding is that the abundance of Calamus started in Rupelian especially in northwest Anatolia (İstanbul and Çanakkale). In the Chattian, mangrove elements have not been observed in the palynofloras, however, nearshore dinoflagellates and back mangrove elements are represented abundantly by Calamus. Acrostichum aureum and Arecaceae have been recorded less abundantly. This absence of mangrove elements and decreasing of the back mangrove elements could be related to the decline in temperature and precipitation (Figure 1). In spite of increasing temperature, finding mangrove elements in the late Chattian has not been possible due to decreasing humidity (Figure 1). Furthermore, abundance of Calamus has been recorded in the Chattian-like Rupelian, and also back mangrove elements have only been represented by abundance of this pollen in the Chattian palynoflora. In the early Miocene (Aquitanian), brackish condition has been characterized by less abundant nearshore palynomorphs (1–2%; except for Erzurum, Muş and Kars regions) and back mangrove elements (Calamus, Acrostichum aureum, Arecaceae and Myrtaceae; 1–6%). From the Chattian to Aquitanian, values of the precipitation have been significantly increased (Figures 1–3). However, temperature values of this time interval have been decreased. Moreover, terrestrial condition has been expanded in the Aquitanian. Because of these inadequate conditions of temperature, precipitation and palaeogeography, mangrove and back mangrove plants have not been recorded in palynoflora of the early Miocene. Mangrove and back mangrove elements represented with Avicennia, Acrostichum aureum and Calamus have been observed in the Langhian (Milas-Kultak) and values of temperature and precipitation have been increased for the last time in the Langhian (mid-Miocene Climatic Optimum; Zachos et al., 2001). From the Serravallian to Tortonian, predominantly terrestrial conditions have been observed, and so brackish plants have not been recorded in the palynoflora of the time interval.

Figure 4. (a) Palaeogeographic globes of the Mediterranean and Paratethyan from Eocene, the Middle Miocene (after Popov et al., 2004; Rögl, 1998; Harzhauser & Piller, 2007), (b) Plants distribution in the mangrove palaeocommunity (P: Pelliciera, a: Acrostichum, black circle: Nypa, Ba: Barribtonia, A: Avicennia, R: Rhizophora, S: Sonneratia, Ac: Acanthus, B: Bruguiera, C: Ceriops and E: Excoecaria) (Plaziat, Cavagnetto, Koeniguer, & Baltzer, 2001). (“Red “A” for the studied section).

5. Palaeoclimatic correlation

For the Eocene, palaeoclimatic change in Europe used the CA and has been summarized by the Utescher, Bruch, Micheels, Mosbrugger, and Popova (2011), and authors suggested that warm climatic conditions have been observed in NW Europe and Western Russia based on high CMT anomalies. The CA results of Anatolia represented 9–14 °C (absolute temperature) and > 20 °C of CMT has indicated warm climatic conditions like Western Russia and NW Europe (Figures 5(a), 6(a), and 7(a); Table 1). During the Eocene, humidity is strong and high MAP, MAPwarm, MAPwet and MAPdry values have been supported these humid conditions (Figures 8(a) and 9(a)).

Figure 5. Mean annual temperature in Europe and Anatolia: (a) Eocene, (b) Rupelian, (c) Chattian, (d) Aquitanian, (e) Burdigalian and (f) Langhian and legend of Figure 9.

Figure 6. Mean annual coldest month in Europe and Anatolia: (a) Eocene, (b) Rupelian, (c) Chattian, (d) Aquitanian, (e) Burdigalian and (f) Langhian and legend of Figure 9.

Figure 7. Mean annual warmest month in Europe and Anatolia: (a) Eocene, (b) Rupelian, (c) Chattian, (d) Aquitanian, (e) Burdigalian and (f) Langhian and legend of Figure 9.

Figure 8. Mean annual precipitation in the Europe and Anatolia: (a) Eocene, (b) Rupelian, (c) Chattian, (d) Aquitanian, (e) Burdigalian and (f) Langhian and legend of Figure 9.

Figure 9 . Precipitation of driest, wettest and warmest months in Europe and Anatolia: (a) Eocene, (b) Rupelian, (c) Chattian, (d) Aquitanian, (e) Burdigalian and (f) Langhian, location of countries and coexistence intervals.

CA values of the Rupelian are not enough for detailed palaeoclimatic interpretation. However, palaeoclimatic warming has been observed from Europe to Bulgaria and NW Anatolia (Figures 5(b), 6(b), and 7(b); Table 2). Furthermore, decrease of the CMT and WMT values has been recorded from western (9–17 °C; CMT) to eastern Anatolia (6–8 °C; CMT). This decline represented by 0–5 °C CMT values has been also reported from the central Russia (Popova, Utescher, Gromyko, Bruch, & Mosbrugger, 2012). Humidity is strong in the Rupelian like Eocene (Figures 1, 2, 8(b) and 9(b)).

In the Chattian, the MAT and CMT values have been decreased from western and eastern Anatolia like Rupelian. However, this decline was more significantly recorded in the late Oligocene (15–16 °C; MAT and 2–5 °C; CMT) (Figures 5(c), 6(c), and 7(c); Table 3). During the Oligocene, humidity has been decreased based on the MAP, MAPdry, MAPwet and MAPwarm, although it has been increased from eastern to western Anatolia (Figures 1, 2, 8(b,c) and 9(b,c)).

From the Chattian to Aquitanian, the CMT values have been remarkably decreased (Figures 5(d), 6(d), and 7(d); Table 4). Strong humid condition have been recorded in Anatolia during the Aquitanian. Besides, during the Chat–Aquitanian, climatic variables of the central Russia are lower than the variables of Anatolia like Rupelian. Furthermore, decreasing of humidity observed during the Oligocene has been also recorded in the Aquitanian based on the MAPdry and MAPwet values (Figures 1, 2, 8(b)–(d) and 9(b)–(d)).

In the Burdigalian–Langhian interval, the MAT, CMT and WMT values during the Mid-Miocene Climatic Optimum were among the warmest values in Europe and Anatolia (except for Bulgaria, N. Germany and Ukraine Plain) (Figures 1, 2, 5(e,f), 6(e,f), and 7(e,f)). However, these values (especially CMT values) have been decreased from central Anatolia to eastern Anatolia, central Russia, Western and Eastern Serbia (Figure 6(e) and (f)). Furthermore, CMT values of the inland area during the Langhian, generally recorded from the region of Western Anatolia, were lower than the values of Langhian localities in Europe (Figure 2). According to the MAP values, humidity is stronger like the Europe (Figure 8(e,f) and 9(e,f)) in the Burdigalian–Langhian interval. The high CMT values have been observed along the horizontal zone in Mediterranean countries today (Figure 6(f)).

The most significant cooling was recorded from the Langhian to Serravallian in Anatolia and Europe based on the MAT, CMT and WMT values (Figure 10(a)). Besides, the warmest area has been recorded in the central Anatolia. From the Serravallian to earliest Tortonian, decline of these values has been continued (Figure 2). Based on the MAP values, rainfall of central and Anatolia is similar to the central European precipitation during the Serravallian and Tortonian interval (except for precipitation value in the Late Tortonian recorded from the central Anatolia) (Bruch et al., 2011; Mazzini et al., 2013) (Figure 11(a) and (b)). Especially, coexistence intervals of the middle and late Tortonian were calculated from several locations in Central and Eastern Anatolia. For this reason, these intervals do not reflect the true rainfall and temperature of Anatolia. However, temperature and precipitation values have decreased in the Tortonian.

Figure 10. Mean annual temperature, mean annual coldest month, mean annual warmest month and mean annual precipitation in Europe and Anatolia (a) Serravallian and (b) Tortonian (for detail legend see Figure 9).

Figure 11. Precipitation of driest, wettest and warmest months in Europe and Anatolia: (a) Serravallian and (b) Tortonian (for detail legend see Figure 9).

6. Conclusion

1. According to the palynological data, the most significant change of palaeoclimatic conditions was recorded in transition of the Eocene–Oligocene, and tropical climatic conditions in the Eocene has changed warm subtropical in the Oligocene. The distribution and diversity of plants in mangrove and back mangrove forests declined from the Eocene to Rupelian due to this climatic changing and palaeogeographic differences. The warm climatic conditions in the Eocene may be correlated with the middle Eocene Climatic Optimum.

2. During the Oligocene, subtropical climate was widespread in Anatolia; however, the temperature has indicated fluctuations because of the global climatic changing (Late Oligocene Warming). The lowest temperature values have been calculated from the samples of Eastern Anatolia. During the Oligocene, the mangrove elements have not been recorded in the palynospectra and abundance and variations of back-mangrove elements have been decreased. Moreover, the abundance of Calamoid palm (Calamus) in the Oligocene palynospectra has been significantly increased.

3. Temperature values from the Chattian to Aquitanian have been diminished in Anatolia and this decline could be correlated with the Mi-1 Glaciation. The lowest temperature values were recorded from the samples of Eastern Anatolia like Oligocene. Also, the mangrove distribution is represented only by the back mangrove elements and the abundance of these elements decreased during the early Miocene. During the Aquitanian, humidity distinctly increased; however, plants of mangrove vegetation have not been reported due to low temperature values. In the Burdigalian, temperature values increased and precipitation values decreased differently from the temperature trend of the Aquitanian. Therefore, mangrove elements have not been observed in the Burdigalian.

4. Increasing of temperature in the Burdigalian continued in the Langhian in the coastal areas (Middle Miocene Climatic Optimum); however, temperature values declined in the terrestrial areas. This temperature decrease could be related to expansion of terrestrial conditions during the Langhian due to tectonic activities in Anatolia.

5. From the Langhian to early Tortonian, temperature and precipitation values significantly decreased; however, these values indicate an increase in the middle Tortonian.

6. According to the palynological data in Anatolia, distribution and variation of the mangrove vegetation were affected by humidity, continentality and temperature. It is noteworthy that two coexistence intervals have been calculated from the samples, including “true mangrove species” (Avicennia) of Eocene and Langhian.

7. Temperature and precipitation values of Anatolia are higher than the values of central Europe, and also the lowest temperature values have been observed in the Western and Eastern Serbia and Central Russia during the Oligo-Miocene interval.

Acknowledgments

The author would like to thank NECLIME members for providing publications, published flora lists, Dr Ecmel Erlat for climatic knowledge of Anatolia today and Özge Karaalioğlu for technical help. This work is a contribution to NECLIME (Neogene Climate Evolution of Eurasia). Erdin Bozkurt, Funda Akgün and two anonymous referees are thanked for their valuable comments and contributions, which greatly improved the paper.