K—Ar dating of the Anakie Metamorphic Group: Evidence for an extension of the Delamerian Orogeny into central Queensland

The Anakie Metamorphic Group of central Queensland is a multiply deformed sequence of psammitic to pelitic metasedimentary and mafic igneous rocks. Although the depositional age is still uncertain, this paper presents K‐Ar dates from four samples which indicate that the sequence was deformed at about 500 Ma in the Middle Cambrian, and thus forms part of the Delamerian‐Ross Orogen of southern Australia and eastern Antarctica. Lithologically and structurally similar rocks in the Lolworth‐Ravenswood Province, farther north in Queensland, may also be part of this belt. The significance of an older age of about 540 Ma from a fifth sample is uncertain. A sixth sample gave a younger age of about 470 Ma and may be partly reset.

Key words:

• Anakie Inlier
• Anakie Metamorphic Group
• Cambrian
• Delamerian Orogeny
• geochronology
• Neoproterozoic
• potassium‐argon dating
• Queensland

Notes

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