A Phanerozoic gridded dataset for palaeogeographic reconstructions.

Global Plate Models are widely used in the Earth Sciences to reconstruct the past geographic position of geological and palaeontological samples. However, the application of Global Plate Models to retrieve 'palaeocoordinates' is not trivial. Different Global Plate Models exist which vary in their complexity, spatiotemporal coverage, reference frame, and intended use.

A transdisciplinary and community-driven database to unravel subduction zone initiation.

Subduction zones are pivotal for the recycling of Earth's outer layer into its interior. However, the conditions under which new subduction zones initiate are enigmatic. Here, we constructed a transdisciplinary database featuring detailed analysis of more than a dozen documented subduction zone initiation events from the last hundred million years.

Episodic zircon age spectra mimic fluctuations in subduction.

Decades of geochronological work have shown the temporal distribution of zircon ages to be episodic on billion-year timescales and seemingly coincident with the lifecycle of supercontinents, but the physical processes behind this episodicity remain contentious. The dominant, end-member models of fluctuating magmatic productivity versus selective preservation of zircon during times of continental assembly have important and very different implications for long-term, global-scale phenomena, including the history of crustal growth, the initiation and evolution of plate tectonics, and the tempo of mantle outgassing over billions of years. Consideration of this episodicity has largely focused on the Precambrian, but here we analyze a large collection of Phanerozoic zircon ages in the context of global, full-plate tectonic models that extend back to the mid-Paleozoic.

SubMachine: Web-Based Tools for Exploring Seismic Tomography and Other Models of Earth's Deep Interior.

We present SubMachine, a collection of web-based tools for the interactive visualization, analysis, and quantitative comparison of global-scale data sets of the Earth's interior. SubMachine focuses on making regional and global-scale seismic tomography models easily accessible to the wider solid Earth community, in order to facilitate collaborative exploration. We have written software tools to visualize and explore over 30 tomography models-individually, side-by-side, or through statistical and averaging tools.

Intraoceanic subduction spanned the Pacific in the Late Cretaceous-Paleocene.

The notorious ~60° bend separating the Hawaiian and Emperor chains marked a prominent change in the motion of the Pacific plate at ~47 Ma (million years ago), but the origin of that change remains an outstanding controversy that bears on the nature of major plate reorganizations. Lesser known but equally significant is a conundrum posed by the pre-bend (~80 to 47 Ma) motion of the Pacific plate, which, according to conventional plate models, was directed toward a fast-spreading ridge, in contradiction to tectonic forcing expectations. Using constraints provided by seismic tomography, paleomagnetism, and continental margin geology, we demonstrate that two intraoceanic subduction zones spanned the width of the North Pacific Ocean in Late Cretaceous through Paleocene time, and we present a simple plate tectonic model that explains how those intraoceanic subduction zones shaped the ~80 to 47 Ma kinematic history of the Pacific realm and drove a major plate reorganization.

Pacific plate motion change caused the Hawaiian-Emperor Bend.

A conspicuous 60° bend of the Hawaiian-Emperor Chain in the north-western Pacific Ocean has variously been interpreted as the result of an abrupt Pacific plate motion change in the Eocene (∼47 Ma), a rapid southward drift of the Hawaiian hotspot before the formation of the bend, or a combination of these two causes. Palaeomagnetic data from the Emperor Seamounts prove ambiguous for constraining the Hawaiian hotspot drift, but mantle flow modelling suggests that the hotspot drifted 4-9° south between 80 and 47 Ma. Here we demonstrate that southward hotspot drift cannot be a sole or dominant mechanism for formation of the Hawaiian-Emperor Bend (HEB).

Global correlation of lower mantle structure and past subduction.

Advances in global seismic tomography have increasingly motivated identification of subducted lithosphere in Earth's deep mantle, creating novel opportunities to link plate tectonics and mantle evolution. Chief among those is the quest for a robust subduction reference frame, wherein the mantle assemblage of subducted lithosphere is used to reconstruct past surface tectonics in an absolute framework anchored in the deep Earth. However, the associations heretofore drawn between lower mantle structure and past subduction have been qualitative and conflicting, so the very assumption of a correlation has yet to be quantitatively corroborated.