A New Reconstruction for Permian East Gondwana Based on Zircon Data From Ophiolite of the East Australian Great Serpentinite Belt

L. A. Milan; E. A. Belousova; R. A. Glen; T. Chapman; J. Kalmbach; B. Fu; P. M. Ashley

doi:10.1029/2020GL090293

A New Reconstruction for Permian East Gondwana Based on Zircon Data From Ophiolite of the East Australian Great Serpentinite Belt

L. A. Milan^*, E. A. Belousova, R. A. Glen, T. Chapman, J. Kalmbach, B. Fu, P. M. Ashley

^*Corresponding author for this work

Research output: Contribution to journal › Letter › peer-review

7 Citations (Scopus)

Abstract

The Great Serpentinite Belt of eastern Australia is a ∼1500 km long dismembered ophiolite assumed to be Cambrian based on studies of small (typically <50 m²) exotic meta-igneous inclusions despite contrasting ages (Cambrian—Devonian) and complex P-T histories. To overcome these issues, we studied a ∼18 km² coherent block of dismembered ophiolite that provides robust geological context to sampling the ophiolite. Zircon U-Pb-Hf-O isotope and trace analyses from three plagiogranite dykes cutting massive gabbro confirm ∼283–277 Ma ages and a mantle source. As a result, we argue older Cambrian to Devonian plagiogranite and subducted blocks were inherited from previous subduction events in eastern Australia. These findings allow us to match the Great Serpentinite Belt with the contemporary Dun Mountain ophiolite (New Zealand) and the Koh ophiolite (New Caledonia), thus supporting a new, integrated Pacific Gondwana margin paleogeography involving multiple arcs and subduction zones.

Original language	English
Article number	e2020GL090293
Journal	Geophysical Research Letters
Volume	48
Issue number	1
DOIs	https://doi.org/10.1029/2020GL090293
Publication status	Published - 16 Jan 2021

Access to Document

10.1029/2020GL090293

Cite this

@article{68fb1bea5cbb4af682b365c79649bb1a,

title = "A New Reconstruction for Permian East Gondwana Based on Zircon Data From Ophiolite of the East Australian Great Serpentinite Belt",

abstract = "The Great Serpentinite Belt of eastern Australia is a ∼1500 km long dismembered ophiolite assumed to be Cambrian based on studies of small (typically <50 m2) exotic meta-igneous inclusions despite contrasting ages (Cambrian—Devonian) and complex P-T histories. To overcome these issues, we studied a ∼18 km2 coherent block of dismembered ophiolite that provides robust geological context to sampling the ophiolite. Zircon U-Pb-Hf-O isotope and trace analyses from three plagiogranite dykes cutting massive gabbro confirm ∼283–277 Ma ages and a mantle source. As a result, we argue older Cambrian to Devonian plagiogranite and subducted blocks were inherited from previous subduction events in eastern Australia. These findings allow us to match the Great Serpentinite Belt with the contemporary Dun Mountain ophiolite (New Zealand) and the Koh ophiolite (New Caledonia), thus supporting a new, integrated Pacific Gondwana margin paleogeography involving multiple arcs and subduction zones.",

keywords = "Great Serpentinite Belt, New England Orogen, Zircon U-Pb-Hf-O isotopes, ophiolite, oxygen isotopes, plagiogranite",

author = "Milan, {L. A.} and Belousova, {E. A.} and Glen, {R. A.} and T. Chapman and J. Kalmbach and B. Fu and Ashley, {P. M.}",

year = "2021",

month = jan,

day = "16",

doi = "10.1029/2020GL090293",

language = "English",

volume = "48",

journal = "Geophysical Research Letters",

issn = "0094-8276",

publisher = "John Wiley & Sons Inc.",

number = "1",

}

TY - JOUR

T1 - A New Reconstruction for Permian East Gondwana Based on Zircon Data From Ophiolite of the East Australian Great Serpentinite Belt

AU - Milan, L. A.

AU - Belousova, E. A.

AU - Glen, R. A.

AU - Chapman, T.

AU - Kalmbach, J.

AU - Fu, B.

AU - Ashley, P. M.

PY - 2021/1/16

Y1 - 2021/1/16

N2 - The Great Serpentinite Belt of eastern Australia is a ∼1500 km long dismembered ophiolite assumed to be Cambrian based on studies of small (typically <50 m2) exotic meta-igneous inclusions despite contrasting ages (Cambrian—Devonian) and complex P-T histories. To overcome these issues, we studied a ∼18 km2 coherent block of dismembered ophiolite that provides robust geological context to sampling the ophiolite. Zircon U-Pb-Hf-O isotope and trace analyses from three plagiogranite dykes cutting massive gabbro confirm ∼283–277 Ma ages and a mantle source. As a result, we argue older Cambrian to Devonian plagiogranite and subducted blocks were inherited from previous subduction events in eastern Australia. These findings allow us to match the Great Serpentinite Belt with the contemporary Dun Mountain ophiolite (New Zealand) and the Koh ophiolite (New Caledonia), thus supporting a new, integrated Pacific Gondwana margin paleogeography involving multiple arcs and subduction zones.

AB - The Great Serpentinite Belt of eastern Australia is a ∼1500 km long dismembered ophiolite assumed to be Cambrian based on studies of small (typically <50 m2) exotic meta-igneous inclusions despite contrasting ages (Cambrian—Devonian) and complex P-T histories. To overcome these issues, we studied a ∼18 km2 coherent block of dismembered ophiolite that provides robust geological context to sampling the ophiolite. Zircon U-Pb-Hf-O isotope and trace analyses from three plagiogranite dykes cutting massive gabbro confirm ∼283–277 Ma ages and a mantle source. As a result, we argue older Cambrian to Devonian plagiogranite and subducted blocks were inherited from previous subduction events in eastern Australia. These findings allow us to match the Great Serpentinite Belt with the contemporary Dun Mountain ophiolite (New Zealand) and the Koh ophiolite (New Caledonia), thus supporting a new, integrated Pacific Gondwana margin paleogeography involving multiple arcs and subduction zones.

KW - Great Serpentinite Belt

KW - New England Orogen

KW - Zircon U-Pb-Hf-O isotopes

KW - ophiolite

KW - oxygen isotopes

KW - plagiogranite

UR - http://www.scopus.com/inward/record.url?scp=85100064511&partnerID=8YFLogxK

U2 - 10.1029/2020GL090293

DO - 10.1029/2020GL090293

M3 - Letter

SN - 0094-8276

VL - 48

JO - Geophysical Research Letters

JF - Geophysical Research Letters

IS - 1

M1 - e2020GL090293

ER -

A New Reconstruction for Permian East Gondwana Based on Zircon Data From Ophiolite of the East Australian Great Serpentinite Belt

Abstract

Access to Document

Other files and links

Fingerprint

Cite this