The Taylor Group (Beacon Supergroup): the Devonian sediments of Antarctica

Abstract

The Taylor Group, the lower division of the Beacon Supergroup, comprises mainly quartzose sandstones of Devonian age deposited after the development of the Kukri Erosion Surface across the Cambrian Ross orogen. Devonian sediments accumulated in a McMurdo Basin that now incorporates most of the Transantarctic Mountains, and a larger Ellsworth Basin that extends from West Antarctica into southern Africa. In southern Victoria Land (McMurdo Basin) the seven formations total around 1200 m in thickness. Sequence stratigraphy suggests five sedimentary cycles, the lower four of which may show shallow marine influence. Provenance studies indicate derivation solely from Ross Orogen sources. The Taylor Group in the central Transantarctic Mountains consists of two thin formations, only one of which is extensive. In the Ellsworth Basin, Taylor Group equivalents rest concordantly on thick piles of post-Ross Palaeozoic sediment. Shallow-water Devonian sediments in the Ohio Range contain a marine fauna linked with those of the Ellsworth Mountains, southern Africa, South America, New Zealand and Australia. A seaway probably existed along the Pacific edge of the East Antarctic craton, allowing these faunal links, and may also have communicated with the McMurdo Basin to drive the five sedimentary sequences.

Applications of detrital geochronology and thermochronology from glacial deposits to the Paleozoic and Mesozoic thermal history of the Ross Embayment, Antarctica

“…Following the Ross Orogeny, exhumation and erosion of the granitic and metamorphic basement of East Antarctica produced the Kukri Peneplain [Gunn and Warren, 1962]. This erosional unconformity separates Ordovician and older bedrock of East Antarctica and the overlying Beacon Supergroup, and is inferred to have formed in the middle Devonian [Bradshaw, 2013]. Sediments of the Beacon Supergroup were deposited on the Kukri Erosional Surface into a basin or basins located between the East Antarctic craton and West Antarctic volcanic rocks that formed along a Permo-Triassic magmatic arc from subduction of the proto-Pacific Ocean plate [Barrett, 1991;Collinson et al, 1994;Isbell, 1999;Elliot and Fanning, 2008].…”

Schroeder Hill, central Transantarctic Mountains, Antarctica: Triassic stratigraphy and Sirius Group glacigenic deposits

“…On that surface unfossiliferous sandstones were deposited, now represented by thin successions at scattered outcrops (Coates 1985, Isbell 1999). These beds are stratigraphically correlative with the Devonian Taylor Group of southern Victoria Land (Bradshaw 2013). A pre-Permian erosion surface (Maya Erosion Surface) was developed across all older rocks, and on this younger surface the Permian-Triassic Victoria Group strata accumulated.…”

Antarctica's sedimentary basins and their influence on ice sheet dynamics

“…The Beacon Supergroup comprises the basal Taylor Group and the overlying Victoria Group. The Taylor Group consists of Devonian clastic sedimentary rocks, predominated by shallow marine sediments grading to fluvial sediments [Bradshaw, 2013]. The unconformably overlying Victoria Group and regional equivalents consists of Permian-Triassic siliciclastic and volcaniclastic rocks also including glacial deposits and coal beds [Elliot et al, 2017].…”