A tracer-based algorithm for automatic generation of seafloor age grids from plate tectonic reconstructions

Abstract. Paleogeographic reconstructions are important to understand Earth's tectonic evolution, past eustatic and regional sea level change, hydrocarbon genesis, and to constrain and interpret the dynamic topography predicted by time-dependent global mantle convection models. Several global paleogeographic maps have been compiled and published but they are generally presented as static maps with varying temporal resolution and fixed spatial resolution. Existing global paleogeographic maps are also tied to a particular plate motion model, making it difficult to link them to alternative digital plate tectonic reconstructions. To address this limitation, we developed a workflow to reverse-engineer global paleogeographic maps to their present-day coordinates and enable them to be linked to any tectonic reconstruction. Published paleogeographic compilations are also tied to fixed input datasets. We used fossil data from the Paleobiology Database to identify inconsistencies between fossils paleo-environments and published paleogeographic maps, and to improve the location of inferred terrestrial-marine boundaries by resolving these inconsistencies. As a result, the overall consistency ratio between the paleogeography and fossil collections was improved from 76.9 % to 96.1 %. We estimated the surface areas of global paleogeographic features (shallow marine environments, landmasses, mountains and ice sheets), and reconstructed the global continental flooding history since the late Paleozoic based on the amended paleogeographies. Finally, we discuss the relationships between emerged land area and total continental crust area through time, continental growth models, and strontium isotope (87Sr/86Sr) signatures in ocean water. Our study highlights the flexibility of digital paleogeographic models linked to state-of-the-art plate tectonic reconstructions in order to better understand the interplay of continental growth and eustasy, with wider implications for understanding Earth's paleotopography, ocean circulation, and the role of mantle convection in shaping long-wavelength topography.

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Plate-tectonic reconstructions predict part of the Hawaiian hotspot track to be preserved in the Bering Sea

Geology ◽

10.1130/g23383a.1 ◽

2007 ◽

Vol 35 (5) ◽

pp. 407 ◽

Cited By ~ 39

Author(s):

Bernhard Steinberger ◽

Carmen Gaina

Keyword(s):

Bering Sea ◽

Plate Tectonic ◽

Tectonic Reconstructions ◽

The Bering Sea

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Plate tectonic reconstructions with continuously closing plates

Computers & Geosciences ◽

10.1016/j.cageo.2011.04.014 ◽

2012 ◽

Vol 38 (1) ◽

pp. 35-42 ◽

Cited By ~ 170

Author(s):

Michael Gurnis ◽

Mark Turner ◽

Sabin Zahirovic ◽

Lydia DiCaprio ◽

Sonja Spasojevic ◽

...

Keyword(s):

Plate Tectonic ◽

Tectonic Reconstructions

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Uncertainties in break-up markers along the Iberia–Newfoundland margins illustrated by new seismic data

Solid Earth ◽

10.5194/se-11-397-2020 ◽

2020 ◽

Vol 11 (2) ◽

pp. 397-417 ◽

Cited By ~ 1

Author(s):

Annabel Causer ◽

Lucía Pérez-Díaz ◽

Jürgen Adam ◽

Graeme Eagles

Keyword(s):

Seismic Data ◽

Direct Consequence ◽

Magnetic Anomalies ◽

Oceanic Lithosphere ◽

High Amplitude ◽

Plate Tectonic ◽

Plate Models ◽

Plate Reconstructions ◽

Tectonic Reconstructions ◽

Break Up

Abstract. Plate tectonic modellers often rely on the identification of “break-up” markers to reconstruct the early stages of continental separation. Along the Iberian-Newfoundland margin, so-called break-up markers include interpretations of old magnetic anomalies from the M series, as well as the “J anomaly”. These have been used as the basis for plate tectonic reconstructions are based on the concept that these anomalies pinpoint the location of first oceanic lithosphere. However, uncertainties in the location and interpretation of break-up markers, as well as the difficulty in dating them precisely, has led to plate models that differ in both the timing and relative palaeo-positions of Iberia and Newfoundland during separation. We use newly available seismic data from the Southern Newfoundland Basin (SNB) to assess the suitability of commonly used break-up markers along the Newfoundland margin for plate kinematic reconstructions. Our data show that basement associated with the younger M-series magnetic anomalies is comprised of exhumed mantle and magmatic additions and most likely represents transitional domains and not true oceanic lithosphere. Because rifting propagated northward, we argue that M-series anomaly identifications further north, although in a region not imaged by our seismic, are also unlikely to be diagnostic of true oceanic crust beneath the SNB. Similarly, our data also allow us to show that the high amplitude of the J Anomaly is associated with a zone of exhumed mantle punctuated by significant volcanic additions and at times characterized by interbedded volcanics and sediments. Magmatic activity in the SNB at a time coinciding with M4 (128 Ma) and the presence of SDR packages onlapping onto a basement fault suggest that, at this time, plate divergence was still being accommodated by tectonic faulting. We illustrate the differences in the relative positions of Iberia and Newfoundland across published plate reconstructions and discuss how these are a direct consequence of the uncertainties introduced into the modelling procedure by the use of extended continental margin data (dubious magnetic anomaly identifications, break-up unconformity interpretations). We conclude that a different approach is needed for constraining plate kinematics of the Iberian plate pre-M0 times.

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