![Sample our Environment & Agriculture journals, sign in here to start your access, latest two full volumes FREE to you for 14 days]({"type":"image" , "src" : "/sda/5934/TOC-Subject-Sample-2021-Environment-Agriculture.jpg"})
ABSTRACT
The Givetian to Famennian (Middle-Upper Devonian) Bahram Formation deposits (Bondar and Shahzadeh Mohammad sections) in the Kerman region, Central Iran were sampled for conodonts. The conodonts were described, their distribution investigated, and the studied sections were correlated. In the previous conodont-based papers, the age of the Bahram Formation in the Kerman region was from the upper Givetian hermanni Zone to the middle Famennian Uppermost marginifera Zone (Middle to Late Devonian). However, the new results of this study show that the Bondar section spans from the middle Givetian ansatus Zone to the upper Famennian (middle part of the Middle expansa Zone = Bispathodus aculeatus aculeatus Zone) and the Shahzadeh Mohammad section spans from the middle Givetian ansatus Zone to the lower Famennian (Uppermost crepida = Palmatolepis glabra pectinata) Zone. In both of the studied sections, the Givetian/Frasnian boundary has been identified by the first occurrence of Ancyrodella rotundiloba pristina, but there is no obvious (sedimentological or biostratigraphic) evidence to define the Frasnian/Famennian boundary.
Acknowledgements
The authors are thankful to Ebrahim Mohammadi and Hossein Zamani for helping in the sampling of the sections. Ebrahim Mohammadi provided useful comments on an early version of the manuscript. Raimund Feist is gratefully acknowledged for his special attention. Carlo Corradini is gratefully appreciated for his help in taxonomic identifications. We thank both reviewers Jau-Chyn Liao and Jose I. Valenzuela-Rios; their constructive comments, criticisms and suggestions significantly improved the quality of this paper. The authors are grateful to the Vice Chancellor for Research and Technology at University of Isfahan for financial and logistic supports. This is contribution ISEM 2020-225.
Disclosure statement
No potential conflict of interest was reported by the authors.
Plate 1. Selected conodonts from the Bondar section. The collection is stored in the Department of Geology, University of Isfahan. All figured conodonts are P1 and/or I elements.
1, 2- Polygnathus ansatus Ziegler & Klapper 1976 (in Ziegler et al. Citation1976); (1) upper view of EUIC B235, Sample B1. (2) upper view of EUIC B254, Sample B1.
3, 4- Polygnathus rhenanus Klapper, Philip & Jackson 1970; (3) upper view of EUIC B238, Sample B1; (4) upper view of EUIC B239, Sample B1.
5-7- Polygnathus varcus Stauffer 1940; (5) upper view of EUIC B300, Sample B2; (6) upper view of EUIC B241, Sample B1; (7) upper view of EUIC B256, Sample B1.
8- Polygnathus aff. varcus Stauffer 1940; upper view of EUIC B255, Sample B1.
9-10- Polygnathus xylus Stauffer 1940; (9) upper view of EUIC B240, Sample B1; (10) upper view of EUIC B286, Sample B2.
11-14- Icriodus brevis Stauffer 1940; (11) upper view of EUIC B264, Sample B1; (12) upper view of EUIC B271, Sample B1; (13) upper view of EUIC B268, Sample B1; (14) upper view of EUIC B269, Sample B1.
15-Icriodus cf. lilliputensis Bultynck (Citation1987); upper view of EUIC B277, Sample B1.
16, 17- Icriodus subterminus Youngquist 1947; (16) upper view of EUIC B385, Sample B11; (17) upper view of EUIC B389, Sample B11.
18- Icriodus difficilis Ziegler et al. (Citation1976); upper view of EUIC B402, Sample B11.
19- Icriodus arkonensis walliserianus Weddige 1988; upper view of EUIC B311, Sample B3.
20- Icriodus aff. difficilis Ziegler et al. (Citation1976); upper view of EUIC B312, Sample B3.
21- Icriodus lindensis Weddige 1977; upper view of EUIC B315, Sample B3.
22, 23- Icriodus subterminus Youngquist 1947; (22) upper view of EUIC B345, Sample B9; (23) upper view of EUIC B337, Sample B9.
24- Icriodus difficilis Ziegler et al. (Citation1976); upper view of EUIC B339, Sample B9.
25, 26- Icriodus expansus Branson & Mehl 1938; (25) upper view of EUIC B413, Sample B19; (26) upper view of EUIC B414, Sample B19.
27- Polygnathus cf. denisbriceae Bultynck 1979; upper view of EUIC B323, Sample B3.
28-30- Polygnathus alatus Huddle 1934; (28) upper view of EUIC B376, Sample B11; (29) upper view of EUIC B368, Sample B11; (30) upper view of EUIC B381, Sample B11.
31- Polygnathus praepolitus Kononova, Alekseev, Braskov & Reimers 1996; upper view of EUIC B417, Sample B19.
32, 33- Polygnathus politus Ovnatanova 1969; (32) upper view of EUIC B418, Sample B19; (33) upper view of EUIC B419, Sample B19.
34- Polygnathus aspelundi Savage & Funai 1980; upper view of EUIC B422, Sample B20.
35- Ancyrodella rotundiloba pristina, Khalymbadzha & Chernyscheva 1970; upper view of EUIC B367, Sample B11.
36- Polygnathus praepolitus Kononova, Alekseev, Braskov & Reimers 1996; upper view of EUIC B403, Sample B12.
37- Polygnathus ovatinodosus Ziegler & Klapper 1976; upper view of EUIC B405, Sample B12.
38, 39- Polygnathus zinaidae Kononova, Alekseev, Braskov & Reimers 1996; (38) upper view of EUIC B412, Sample B18; (39) upper view of EUIC B420, Sample B19.
40- Polygnathus seraphimae Ovnatanova & Kononova 1996; upper view of EUIC B425, Sample B20.
41- Polygnathus webbi Stauffer 1938; upper view of EUIC B433, Sample B23.
Plate 2. Selected conodonts from the Bondar section. The collection is stored in the Department of Geology, University of Isfahan. All figured conodonts are P1 and/or I elements.
1, 2- Icriodus excavatus Weddige 1984; (1) upper view of EUIC B440, Sample B23; (2) upper view of EUIC B443, Sample B23.
3, 4- Icriodus alternatus alternatus Branson & Mehl 1934; (3) upper view of EUIC B468, Sample B37; (4) upper view of EUIC B467, Sample B37.
5, 6- Polygnathus webbi Stauffer 1938; (5) upper view of EUIC B448, Sample B24; (6) upper view of EUIC B450, Sample B25.
7- Icriodus iowaensis iowaensis Youngquist & Peterson 1947; upper view of EUIC B470, Sample B37.
8- Polygnathus aequalis Klapper and Lane (1985); (8) upper view of EUIC B452, Sample B25.
9, 10- Icriodus cedarensis Narkiewicz and Bultynck (Citation2010); (9) upper view of EUIC B458, Sample B25; (10) upper view of EUIC B460, Sample B25.
11- Icriodus cornutus Sannemann 1955; upper view of EUIC B477, Sample B43.
12, 13- Pelekysgnathus inclinatus Thomas 1949; (12) oblique-lateral view of EUIC B479, Sample B43; (13) upper view of EUIC B483, Sample B44.
14- Bispathodus stabilis vulgaris Dzik 2006; upper view of EUIC B492, Sample B44.
15- Bispathodus aculeatus anteposicornis Scott 1961; upper view of EUIC B499, Sample B49.
16, 17- Polygnathus communis dentatus Druce (Citation1969); (16) upper view of EUIC B489, Sample B44; (17) upper view of EUIC B496, Sample B45.
18- Polygnathus communis communis Branson & Mehl 1934; upper view of EUIC B495, Sample B45.
19, 20- Polygnathus communis collinsoni Druce (Citation1969); (19) upper view of EUIC B491, Sample B44; (20) upper view of EUIC B490, Sample B44.
21- Polygnathus spicatus Branson 1934; upper view of EUIC B515, Sample B51.
22- Polygnathus inornatus Branson & Mehl 1934; upper view of EUIC B517, Sample B53.
23- Pandorinellina cf. insita sensu Sandberg & Ziegler (Citation1979); upper view of EUIC B486, Sample B44.
24, 25- Clydagnathus plumulus Rhodes et al. 1969; (24) upper view of EUIC B501, Sample B49; (25) upper view of EUIC B502, Sample B49.
26- Pseudopolygnathus primus Branson & Mehl 1934; upper view of EUIC B503, Sample B49.
27- Clydagnathus ormistoni Beinert, Klapper, Sandberg & Ziegler 1971; upper view of EUIC B505, Sample B50.
28-30- Clydagnathus tragelehni Hartenfels (Citation2011); (28) upper view of EUIC B506, Sample B50; (29) upper view of EUIC B508, Sample B50; (30) upper view of EUIC B509, Sample B50.
31- Clydagnathus ormistoni Beinert, Klapper, Sandberg & Ziegler 1971; upper view of EUIC B512, Sample B51.
Plate 3. Selected conodonts from the Shahzadeh Mohammad section. The collection is stored in the Department of Geology, University of Isfahan. All figured conodonts are P1 and/or I elements.
1- Polygnathus xylus Stauffer 1940; upper view of EUIC S519, Sample Sh7.
2- Polygnathus ansatus Ziegler & Klapper 1976 (in Ziegler et al. Citation1976); upper view of EUIC S523, Sample Sh7.
3, 5-6- Polygnathus varcus Stauffer 1940; (3) upper view of EUIC S543, Sample Sh8; (5) upper view of EUIC S551, Sample Sh9; (6) upper view of EUIC S557, Sample Sh10.
4- Polygnathus cf. varcus Stauffer 1940; upper view of EUIC S545, Sample Sh9.
7-9- Polygnathus ovatinodosus Ziegler & Klapper 1976; (7) upper view of EUIC S546, Sample Sh9; (8) upper view of EUIC S547, Sample Sh9; (9) upper view of EUIC S560, Sample Sh10.
10- Polygnathus xylus Stauffer 1940; upper view of EUIC S558, Sample Sh10.
11- Polygnathus alatus Huddle 1934; upper view of EUIC S568, Sample Sh12.
12- Icriodus arkonensis arkonensis Stauffer 1938; upper view of EUIC S527, Sample Sh7.
13-15, 19, 20- Icriodus brevis Stauffer 1940; (13) upper view of EUIC S530, Sample Sh7; (14) upper view of EUIC S534, Sample Sh7; (15) upper view of EUIC S555, Sample Sh10; (19) upper view of EUIC S529, Sample Sh7; (20) upper view of EUIC S538, Sample Sh8.
16-18- Icriodus difficilis Ziegler et al. (Citation1976); (16) upper view of EUIC S532, Sample Sh7; (17) upper view of EUIC S539, Sample Sh8; (18) upper view of EUIC S588, Sample Sh13.
21- Icriodus tafilaltensis Narkiewicz & Bultynck (Citation2010); upper view of EUIC S579, Sample Sh12.
22, 23- Ancyrodella rotundiloba pristina, Khalymbadzha & Chemysheva 1970; (22) upper view of EUIC S566, Sample Sh12; (23) upper view of EUIC S567, Sample Sh12.
24, 25- Polygnathus praepolitus Kononova, Alekseev, Braskov & Reimers 1996; (24) upper view of EUIC S570, Sample Sh12; (25) upper view of EUIC S574, Sample Sh12.
26- Polygnathus dubius Hinde 1879; upper view of EUIC S573, Sample Sh12.
27-29- Polygnathus aequalis Klapper & Lane 1985; (27) upper view of EUIC S593, Sample Sh13; (28) upper view of EUIC S594, Sample Sh13; (29) upper view of EUIC S595, Sample Sh13.
30, 31- Icriodus symmetricus Branson & Mehl 1934; (30) upper view of EUIC S600, Sample Sh17; (31) upper view of EUIC S580, Sample Sh12.
32-34- Icriodus subterminus Youngquist 1947; (32) upper view of EUIC S552, Sample Sh9; (33) upper view of EUIC S553, Sample Sh9; (34) upper view of EUIC S587, Sample Sh13.
35-37- Icriodus expansus Branson & Mehl 1938; (35) upper view of EUIC S584, Sample Sh12; (36) upper view of EUIC S614, Sample Sh23; (37) upper view of EUIC S616, Sample Sh24.
38-39- Icriodus cornutus Sannemann 1955; (38) upper view of EUIC S683, Sample Sh35; (39) upper view of EUIC S697, Sample Sh38.
40-43- Polygnathus praepolitus Kononova, Alekseev, Braskov & Reimers 1996; (40) upper view of EUIC S603, Sample Sh18; (41) upper view of EUIC S607, Sample Sh19; (42) upper view of EUIC S612, Sample Sh20; (43) upper view of EUIC S625, Sample Sh26.
44, 45- Polygnathus alatus Huddle 1934; (44) upper view of EUIC S599, Sample Sh17; (45) upper view of EUIC S611, Sample Sh20.
46- Polygnathus zinaidae Kononova, Alekseev, Braskov & Reimers 1996; upper view of EUIC S605, Sample Sh18.
47, 48- Polygnathus seraphimae Ovnatanova & Kononova 1996; (47) upper view of EUIC S604, Sample Sh18; (48) upper view of EUIC S609, Sample Sh19;
49- Polygnathus cf. seraphimae Ovnatanova & Kononova 1996; upper view of EUIC S622, Sample Sh26.
Plate 4. Selected conodonts from the Shahzadeh Mohammad section. The collection is stored in Department of Geology, University of Isfahan. All figured conodonts are P1 and/or I elements.
1-3- Polygnathus brevilaminus Branson & Mehl 1934; (1) upper view of EUIC S657, Sample Sh32; (2) upper view of EUIC S660, Sample Sh40; (3) upper view of EUIC S724, Sample Sh33.
4, 5- Polygnathus angustidiscus Youngquist 1945; (4) upper view of EUIC S658, Sample Sh33; (5) upper view of EUIC S687, Sample Sh36.
6-9- Polygnathus semicostatus Branson & Mehl 1934; (6) upper view of EUIC S700, Sample Sh38; (7) upper view of EUIC S705, Sample Sh39; (8) upper view of EUIC S708, Sample Sh39; (9) upper view of EUIC S719, Sample Sh40.
10- Polygnathus procerus Sannemann 1955; upper view of EUIC S723, Sample Sh40.
11-14- Icriodus alternatus alternatus Branson & Mehl 1934; (11) upper view of EUIC S696, Sample Sh38; (12) upper view of EUIC S651, Sample Sh32; (13) upper view of EUIC S682, Sample Sh35; (14) upper view of EUIC S732, Sample Sh40.
15-18- Icriodus iowaensis iowaensis Youngquist & Peterson 1947; (15) upper view of EUIC S636, Sample Sh29; (16) upper view of EUIC S644, Sample Sh32; (17) upper view of EUIC S670, Sample Sh33; (18) upper view of EUIC S666, Sample Sh33.
19- Pelekysgnathus inclinatus Thomas 1949; lateral view of EUIC S734, Sample Sh40.
20, 21- Pelekysgnathus serradentatus Capkinoglu 1991; (20) upper view of EUIC S699, Sample Sh38; (21) upper view of EUIC S710, Sample Sh39.
22, 23- Polygnathus praepolitus Kononova, Alekseev, Braskov & Reimers 1996; (22) upper view of EUIC S623, Sample Sh26; (23) upper view of EUIC S624, Sample Sh26.
24-26- Polygnathus aspelundi Savage & Funai 1980; (24) upper view of EUIC S 619, Sample Sh24; (25) upper view of EUIC S618, Sample Sh24; (26) upper view of EUIC S630, Sample Sh29.
27, 28- Ancyrodella sp.; (27) upper view of EUIC S598, Sample Sh13; (28) upper view of EUIC S597, Sample Sh13.
29- Polygnathus webbi Stauffer 1938; upper view of EUIC S628, Sample Sh27.
30- Polygnathus krestovnikovi Ovnatanova 1969; upper view of EUIC S662, Sample Sh33.