Description
Summary:This data collection is associated with the publication: Gibbons, A. D., Whittaker, J. M., & Müller, R. D. (2013). The breakup of East Gondwana: Assimilating constraints from Cretaceous ocean basins around India into a best-fit tectonic model. Journal of Geophysical Research: Solid Earth, 118(3), 808-822. doi:10.1002/jgrb.50079 Publication Abstract Published models for the Cretaceous seafloor-spreading history of East Gondwana result in unlikely tectonic scenarios for at least one of the plate boundaries involved and/or violate particular constraints from at least one of the associated ocean basins. We link East Gondwana spreading corridors by integrating magnetic and gravity anomaly data from the Enderby Basin off East Antarctica within a regional plate kinematic framework to identify a conjugate series of east-west-trending magnetic anomalies, M4 to M0 (~126.7–120.4 Ma). The mid-ocean ridge that separated Greater India from Australia-Antarctica propagated from north to south, starting at ~136Ma northwest of Australia, and reached the southern tip of India at ~126 Ma. Seafloor spreading in the Enderby Basin was abandoned at ~115 Ma, when a ridge jump transferred the Elan Bank and South Kerguelen Plateau to the Antarctic plate. Our revised plate kinematic model helps resolve the problem of successive two-way strike-slip motion between Madagascar and India seen in many previously published reconstructions and also suggests that seafloor spreading between them progressed from south to north from 94 to 84 Ma. This timing is essential for tectonic flow lines to match the curved fracture zones of the Wharton and Enderby basins, as Greater India gradually began to unzip from Madagascar from ~100 Ma. In our model, the 85-East Ridge and Kerguelen Fracture Zone formed as conjugate flanks of a “leaky” transform fault following the ~100Ma spreading reorganization. Our model also identifies the Afanasy Nikitin Seamounts as products of the Conrad Rise hotspot. Authors and Institutions Ana D. Gibbons - EarthByte Research Group, School of Geosciences, The University of Sydney, Australia Joanne M. Whittaker - EarthByte Research Group, School of Geosciences, The University of Sydney, Australia. ORCID: 0000-0002-3170-3935 R. Dietmar Müller - EarthByte Research Group, School of Geosciences, The University of Sydney, Australia. ORCID: 0000-0002-3334-5764 Overview of Resources Contained This data collection includes the all of the files needed to visualise, recreate, and interact with the plate motion model developed and published in Gibbons et al. (2013). Data used in the development of the plate motion model are also included. List of Resources Note: For details on the files included in this data collection, see “Description_of_Resources.txt”. Note: For information on file formats and what programs to use to interact with various file formats, see “File_Formats_and_Recommended_Programs.txt”. Rotation file for the tectonic model (.rot, 537 KB) Continent-ocean boundary geometries (.gpml, .kml, .txt, .shp, total 684 KB) Extinct ridge geometries (.gpml, .kml, .txt, .shp, total 414 KB) Fracture zone geometries (.gpml, .kml, .txt, .shp, total 6.8 MB) Isochron geometries (.gpml, .kml, .txt, .shp, total 4 MB) Large igneous province outlines (.gpml, .kml, .txt, .shp, total 279 KB) Magnetic anomaly picks (.gpmlz, .kml, .txt, .shp, total 17.5 MB) For more information on this data collection, and links to other datasets from the EarthByte Research Group please visit EarthByte For more information about using GPlates, including tutorials and a user manual please visit GPlates or EarthByte