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| Narryer Gneiss Terrane | |
|---|---|
| Stratigraphic range: Archean >3.3 Ga | |
.jpg) Satellite image of Jack Hills in the Narryer Gneiss Terrane | |
| Type | Geological complex |
| Sub-units | Dugel Gneiss, Meeberrie Gneiss, Manfred Complex and metasedimentary rocks |
| Lithology | |
| Primary | Granite |
| Location | |
| Region | Yilgarn Craton |
| Country | Western Australia, Australia |
The Narryer Gneiss Terrane is a geological complex in Western Australia that is composed of a tectonically interleaved and polydeformed mixture of granite, mafic intrusions and metasedimentary rocks in excess of 3.3 billion years old, with the majority of the Narryer Gneiss Terrane in excess of 3.6 billion years old. The rocks have experienced multiple metamorphic events at amphibolite or granulite conditions, resulting in often complete destruction of original igneous or sedimentary (protolith) textures. Importantly, it contains the oldest known samples of the Earth's crust: samples of zircon from the Jack Hills portion of the Narryer Gneiss have been radiometrically dated at 4.4 billion years old, although the majority of zircon crystals are about 3.6-3.8 billion years old.
The Narryer Gneiss Terrane is adjacent to the northernmost margin of the Yilgarn Craton and is abutted on the north by the Gascoyne Complex metasedimentary and metagranite orogen. The Narryer Gneiss Terrane also includes parts of the Yarlarweelor Gneiss which abuts to Nabberu Basin metamorphic sequences of the Bryah-Padbury Basins, where it is present as discontinuous slivers of metamorphic rocks, pelites, metaconglomerates and gneisses caught up within regional strike-slip oblique thrust faults.
The Narryer Gneiss in this far-eastern region may form the basement to the 2.0-1.8 billion year old Proterozoic rocks, and the unconformity surface may be preserved within the thrust sheets.
The Narryer Gneiss Terrane is divided into four major rock sequences (Myers 1990); the Dugel Gneiss, Meeberrie Gneiss, Manfred Complex, and unassigned polydeformed leucocratic gneisses and metasediments.