Abstract We present GlobSed, a new global 5‐arc‐minute total sediment thickness grid for the world's oceans and marginal seas. GlobSed covers larger area than previously published grids incorporates updates NE Atlantic, Arctic, Southern Ocean, Mediterranean regions, which results in 29.7% increase estimated oceanic volume. use this revised lithospheric age to assess relationship between of underlying lithosphere its latitude. An analytical approximation model is used mathematically describe...

A marked bend in the Hawaiian-Emperor seamount chain supposedly resulted from a recent major reorganization of plate-mantle system there 50 million years ago. Although alternative mantle-driven and plate-shifting hypotheses have been proposed, no contemporaneous circum-Pacific plate events identified. We report reconstructions for Australia Antarctica that reveal between 53 Revised Pacific Ocean sea-floor suggest subduction Pacific-Izanagi spreading ridge subsequent Marianas/Tonga-Kermadec...

Abstract Published models for the Cretaceous seafloor‐spreading history of East Gondwana result in unlikely tectonic scenarios at least one plate boundaries involved and/or violate particular constraints from associated ocean basins. We link spreading corridors by integrating magnetic and gravity anomaly data Enderby Basin off Antarctica within a regional kinematic framework to identify conjugate series east‐west‐trending anomalies, M4 M0 (~126.7–120.4 Ma). The mid‐ocean ridge that separated...

Abstract We present an updated oceanic crustal age grid and a set of complementary grids including spreading rate, asymmetry, direction, obliquity. Our data is based on selected magnetic anomaly identifications the plate tectonic model Müller et al. (2019, 10.1029/2018TC005462 ). find mean crust 64.2 Myr, slightly older than previous estimates, mainly due to inclusion pockets Mesozoic aged in Atlantic Mediterranean improvements Jurassic Pacific triangle. This partly compensated by additional...

Abstract A reorganization centered on the Pacific plate occurred ~53–47 million years ago. “top‐down” tectonic mechanism, complete subduction of Izanagi plate, as opposed to a “bottom‐up” mantle flow has been proposed main driver. Verification based marine geophysical observations is impossible most ocean crust recording this event subducted. Using forward modeling approach, which assimilates surface velocities and shallow thermal structure slabs into models, we show that margin‐wide slab...

The most poorly exposed and least understood Gondwana-forming orogen lies largely hidden beneath ice in East Antarctica. Called the Kuunga orogen, its interpolation between scattered outcrops is speculative with differing often contradictory trends proposed, no consensus on location of any sutures. While some discount a suture altogether, paleomagnetic data from Indo-Antarctica Australo-Antarctica do require 3000-5000 km relative displacement during Ediacaran-Cambrian Gondwana amalgamation,...

Alternative reconstructions of the Jurassic northern extent Greater India differ by up to several thousand kilometers. We present a new model that is constrained revised seafloor spreading anomalies, fracture zones and crustal ages based on drillsites/dredges from all abyssal plains along West Australian margin Wharton Basin, where an unexpected sliver (153 Ma) has been found embedded in Cretaceous (95 My old) seafloor. Based zone trajectories, this NeoTethyan must have originally formed...

We present a new, 5 min sediment thickness grid for the Australian‐Antarctic region (60°E–155°E, 30°S–70°S). New seismic reflection and refraction data have been used to add detail conjugate Australian Antarctic margins intervening ocean floor where regional patterns were poorly known previously. On margins, estimates computed from velocity‐depth functions sonobuoy/refraction velocity solutions ground‐truthed against data. For Southeast Indian Ridge abyssal plains, contours Geli et al....

[1] We present a global community data set of fracture zones (FZs), discordant zones, propagating ridges, V-shaped structures and extinct digitized from vertical gravity gradient (VGG) maps. use new semi-automatic FZ tracking program to test the precision our hand-digitized traces find Mean Absolute Deviation less than 3.4 km raw VGG minima that most clearly delineate each feature, 5.4 location predicted by fitting model profiles represent morphology individual FZs. These offsets are small...

Despite decades of study the prerift configuration and early rifting history between Australia Antarctica is not well established. The plate boundary system during Cretaceous includes evolving Kerguelen–Broken Ridge Large Igneous Province in west as conjugate passive transform margin segments Australian Antarctic continents. Previous rigid reconstruction models have highlighted difficulty satisfying all available observations within a single coherent history. We investigate range scenarios...

Magnetic anomaly identifications underpin plate tectonic reconstructions and form the primary dataset from which age of oceanic lithosphere seafloor spreading regimes in ocean basins can be determined.Although these are an invaluable resource, their usefulness to wider scientific community has been limited due lack a central infrastructure organize, host update interpretations.We have developed open-source, community-driven online as repository for quality-checked magnetic all basins.We...

Published plate tectonic models for the Australian‐Antarctic pair imply geologically improbable scenarios at either or both ends of Cretaceous rift and spreading system. Controversy also exists around location motion boundary extending west Australia‐Antarctica, through Kerguelen Plateau region. We present a model relative motions among India, Australia, Antarctica from onset continental rifting to establishment rapid seafloor spreading, ~43 Ma. The conforms wide range geological/geophysical...

We describe a powerful method to explore spatio-temporal relationships within geological and geophysical data sets by analyzing the context of tectonic reconstructions. GPlates is part new generation plate reconstruction software that incorporates functionality familiar from GIS software with added dimension time. Here we use GPlates reconstruct terranes, grids, and paleomagnetic alternative models the assembly Western Australia configuration Rodinia. With ability rapidly visualize...

Abstract Wilkes Land in East Antarctica remains one of the last geological exploration frontiers on Earth. Hidden beneath kilometres ice, its bedrock preserves a poorly-understood tectonic history that mirrors southern Australia and holds critical insights into past supercontinent cycles. Here, we use new recently published Australian Antarctic geophysical data to present novel interpretation age character crystalline basement sedimentary cover interior Land. We combine zircon U–Pb Hf...

Declining atmospheric CO2 concentrations are considered the primary driver for Cenozoic Greenhouse-Icehouse transition, ~34 million years ago. A role tectonically opening Southern Ocean gateways, initiating onset of a thermally isolating Antarctic Circumpolar Current, has been disputed as ocean models have not reproduced expected heat transport to coast. Here we use high-resolution simulations with detailed paleobathymetry demonstrate that tectonics did play fundamental in reorganising...

The Eocene India‐Eurasia collision is a first order tectonic event whose nature and chronology remains controversial. We test two end‐member scenarios using coupled global plate motion‐subduction models. first, conventional model, invokes continental soon after ∼60 Ma between maximum extent Greater India an Andean‐style Eurasian margin. alternative scenario involves minimum NeoTethyan back‐arc at that subsequently subducted along southern Lhasa margin, culminating with continent‐continent...

Abstract Oceanic fracture zone traces are widely used in studies of seafloor morphology and plate kinematics. Satellite altimetry missions have resulted high‐resolution gravity maps which all major zones other tectonic fabric can be identified, numerous scientists digitized such lineaments. We initiated a community effort to maintain low‐cost infrastructure that allows lineaments stored, accessed, updated. A key improvement over past efforts is our processing software (released as GMT5...

Significant E‐W extension and/or compression must have been generated by displacements along the Red River Fault (RRF) since its curvature does not match a small circle centered at Euler pole for Indochina–south China plate pair. The amount of perpendicular to RRF offshore Vietnam depends on magnitude left‐lateral displacement RRF. In general, larger fault, smaller extension. All purely strike‐slip models opening South Sea that assume large (>250 km) encounter major problems because they...