University of Tasmania
Browse

File(s) under permanent embargo

Constraining the Jurassic extent of Greater India: Tectonic evolution of the West Australian margin

journal contribution
posted on 2023-05-17, 17:30 authored by Gibbons, AD, Barckhausen, U, van den Bogaard, P, Werner, R, Joanne WhittakerJoanne Whittaker, Muller, RD
Alternative reconstructions of the Jurassic northern extent of Greater India differ by up to several thousand kilometers.We present a newmodel that is constrained by revised seafloor spreading anomalies, fracture zones and crustal ages based on drillsites/dredges from all the abyssal plains along the West Australian margin and the Wharton Basin, where an unexpected sliver of Jurassic seafloor (153 Ma) has been found embedded in Cretaceous (95 My old) seafloor. Based on fracture zone trajectories, this NeoTethyan sliver must have originally formed along a western extension of the spreading center that formed the Argo Abyssal Plain, separating a western extension of West Argoland/West Burma from Greater India as a ribbon terrane. The NeoTethyan sliver, Zenith and Wallaby plateaus moved as part of Greater India until westward ridge jumps isolated them. Following another spreading reorganization, the Jurassic crust resumed migrating with Greater India until it was re-attached to the Australian plate ~95 Ma. The new Wharton Basin data and kinematic model place strong constraints on the disputed northern Jurassic extent of Greater India. Late Jurassic seafloor spreading must have reached south to the Cuvier Abyssal Plain on the West Australian margin, connected to a spreading ridge wrapping around northern Greater India, but this Jurassic crust is no longer preserved there, having been entirely transferred to the conjugate plate by ridge propagations. This discovery constrains the major portion of Greater India to have been located south of the large-offset Wallaby- Zenith Fracture Zone, excluding much larger previously proposed shapes of Greater India.

History

Publication title

Geochemistry Geophysics Geosystems

Volume

13

Issue

5

Article number

Q05W13

Number

Q05W13

Pagination

1-25

ISSN

1525-2027

Department/School

Institute for Marine and Antarctic Studies

Publisher

Amer Geophysical Union

Place of publication

2000 Florida Ave Nw, Washington, USA, Dc, 20009

Rights statement

Copyright 2012 American Geophysical Union

Repository Status

  • Restricted

Socio-economic Objectives

Expanding knowledge in the earth sciences

Usage metrics

    University Of Tasmania

    Exports

    RefWorks
    BibTeX
    Ref. manager
    Endnote
    DataCite
    NLM
    DC