Atlas of the underworld : Slab remnants in the mantle, their sinking history, and a new outlook on lower mantle viscosity
TL;DR: The Atlas of the Underworld as discussed by the authors is a compilation comprising subduction systems active in the past ~300Myr, assuming no relative horizontal motions between adjacent slabs following break-off, but without assuming a mantle reference frame.
About: This article is published in Tectonophysics.The article was published on 2017-10-01 and is currently open access. It has received 253 citations till now. The article focuses on the topics: Transition zone & Mantle wedge.
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01 Dec 2010
TL;DR: Using zircon in situ U-Pb and Lu-Hf isotopic and bulk-rock geochemical data of Mesozoic-Early Tertiary magmatic rocks sampled along four north-south traverses across the Lhasa Terrane, Wang et al. as discussed by the authors showed that the Lhaasa terrane has ancient basement rocks of Proterozoic and Archean ages (up to 2870 Ma) in its centre with younger and juvenile crust (Phanerozoic) accreted towards its both northern and southern edges.
Abstract: article i nfo The Lhasa Terrane in southern Tibet has long been accepted as the last geological block accreted to Eurasia before its collision with the northward drifting Indian continent in the Cenozoic, but its lithospheric architecture, drift and growth histories and the nature of its northern suture with Eurasia via the Qiangtang Terrane remain enigmatic. Using zircon in situ U-Pb and Lu-Hf isotopic and bulk-rock geochemical data of Mesozoic-Early Tertiary magmatic rocks sampled along four north-south traverses across the Lhasa Terrane, we show that the Lhasa Terrane has ancient basement rocks of Proterozoic and Archean ages (up to 2870 Ma) in its centre with younger and juvenile crust (Phanerozoic) accreted towards its both northern and southern edges. This finding proves that the central Lhasa subterrane was once a microcontinent. This continent has survived from its long journey across the Paleo-Tethyan Ocean basins and has grown at the edges through magmatism resulting from oceanic lithosphere subduction towards beneath it during its journey and subsequent collisions with the Qiangtang Terrane to the north and with the Indian continent to the south. Zircon Hf isotope data indicate significant mantle source contributions to the generation of these granitoid rocks (e.g., ~50-90%, 0-70%, and 30-100% to the Mesozoic magmatism in the southern, central, and northern Lhasa subterranes, respectively). We suggest that much of the Mesozoic magmatism in the Lhasa Terrane may be associated with the southward Bangong-Nujiang Tethyan seafloor subduction beneath the Lhasa Terrane, which likely began in the Middle Permian (or earlier) and ceased in the late Early Cretaceous, and that the significant changes of zircon eHf(t) at ~113 and ~52 Ma record tectonomagmatic activities as a result of slab break-off and related mantle melting events following the Qiangtang-Lhasa amalgamation and India-Lhasa amalgamation, respectively. These results manifest the efficacy of zircons as a chronometer (U-Pb dating) and a geochemical tracer (Hf isotopes) in understanding the origin and histories of lithospheric plates and in revealing the tectonic evolution of old orogenies in the context of plate tectonics.
730 citations
TL;DR: In this paper, the authors use advances made in kinematic restoration software in the last decade with a systematic reconstruction protocol for developing a more quantitative restoration of the Mediterranean region for the last 240 million years.
286 citations
TL;DR: In this article, a map that correlates tectonic units between Alps and western Turkey accompanied by a text providing access to literature data is presented, explaining the concepts used for defining the mapped Tectonic Units, and first-order paleogeographic inferences.
201 citations
Cites background from "Atlas of the underworld : Slab remn..."
...…presently observed beneath westernmost Anatolia (Berk Biryol et al., 2011; Gessner et al. 2013) and defines the eastern termination of the deeply subducted Aegean slab (Spakman et al., 1988; Bijwaard et al., 1998; van Hinsbergen et al., 2005c; Jolivet et al., 2013; van der Meer et al., 2018)....
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...…calculated by van Hinsbergen and Schmid (2012), this means that a total of 1200 km slab length became subducted since 65 Ma. Mantle tomography suggests that the total length of the Aegean (African) slab reaching a depth of at least 1400 km amounts to some 1800 km (van der Meer et al., 2018)....
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01 May 2013
TL;DR: The LLNL G3Dv3.interpolated.txt as discussed by the authors model file is named "Layer{n}_{Layer Descriptor}.txt" where "n" is the layer number from the top of Earth's surface to the core-mantle boundary.
Abstract: Each model file is named "LLNL_G3Dv3.Interpolated.Layer{n}_{Layer Descriptor}.txt" where "n" is the layer number from the top of Earth's surface to the core-mantle boundary. The "Layer Descriptor" often contains just the name of the layer (for example: "Lower_Crust_Bottom"). Others will have the depth if the model were spherical (for example: “Lower_Mantle_1271km"). In addition, some descriptors will have the nominal depth preceded by the letter "a" (for example: "Transition_Zone_a660km_topside"). The "a" means "about" since these are actually undulating layers.
181 citations
Journal Article•
TL;DR: This article reconstructed the Philippine Sea and East Asian plate tectonics from 28 slabs mapped in 3D from global tomography, with a subducted area of ~25% of present-day global oceanic lithosphere.
Abstract: We reconstructed Philippine Sea and East Asian plate tectonics since 52 Ma from 28 slabs mapped in 3-D from global tomography, with a subducted area of ~25% of present-day global oceanic lithosphere. Slab constraints include subducted parts of existing Pacific, Indian, and Philippine Sea oceans, plus wholly subducted proto-South China Sea and newly discovered “East Asian Sea.” Mapped slabs were unfolded and restored to the Earth surface using three methodologies and input to globally consistent plate reconstructions. Important constraints include the following: (1) the Ryukyu slab is ~1000 km N-S, too short to account for ~20° Philippine Sea northward motion from paleolatitudes; (2) the Marianas-Pacific subduction zone was at its present location (±200 km) since 48 ± 10 Ma based on a >1000 km deep slab wall; (3) the 8000 × 2500 km East Asian Sea existed between the Pacific and Indian Oceans at 52 Ma based on lower mantle flat slabs; (4) the Caroline back-arc basin moved with the Pacific, based on the overlapping, coeval Caroline hot spot track. These new constraints allow two classes of Philippine Sea plate models, which we compared to paleomagnetic and geologic data. Our preferred model involves Philippine Sea nucleation above the Manus plume (0°/150°E) near the Pacific-East Asian Sea plate boundary. Large Philippine Sea westward motion and post-40 Ma maximum 80° clockwise rotation accompanied late Eocene-Oligocene collision with the Caroline/Pacific plate. The Philippine Sea moved northward post-25 Ma over the northern East Asian Sea, forming a northern Philippine Sea arc that collided with the SW Japan-Ryukyu margin in the Miocene (~20–14 Ma).
138 citations
References
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TL;DR: A review of the geologic history of the Himalayan-Tibetan orogen suggests that at least 1400 km of north-south shortening has been absorbed by the orogen since the onset of the Indo-Asian collision at about 70 Ma as discussed by the authors.
Abstract: A review of the geologic history of the Himalayan-Tibetan orogen suggests that at least 1400 km of north-south shortening has been absorbed by the orogen since the onset of the Indo-Asian collision at about 70 Ma. Significant crustal shortening, which leads to eventual construction of the Cenozoic Tibetan plateau, began more or less synchronously in the Eocene (50–40 Ma) in the Tethyan Himalaya in the south, and in the Kunlun Shan and the Qilian Shan some 1000–1400 km in the north. The Paleozoic and Mesozoic tectonic histories in the Himalayan-Tibetan orogen exerted a strong control over the Cenozoic strain history and strain distribution. The presence of widespread Triassic flysch complex in the Songpan-Ganzi-Hoh Xil and the Qiangtang terranes can be spatially correlated with Cenozoic volcanism and thrusting in central Tibet. The marked difference in seismic properties of the crust and the upper mantle between southern and central Tibet is a manifestation of both Mesozoic and Cenozoic tectonics. The form...
4,494 citations
4,094 citations
TL;DR: The Karakaya marginal sea was already closed by earliest Jurassic times because early Jurassic sediments unconformably overlie its deformed lithologies as discussed by the authors, and it was closed by collision of the Bitlis-Poturge fragment with Arabia.
2,899 citations
TL;DR: In this article, a plate tectonic model for the Paleozoic and Mesozoic (Ordovician to Cretaceous) integrating dynamic plate boundaries, plate buoyancy, ocean spreading rates and major Tectonic and magmatic events was developed.
2,310 citations
TL;DR: In this article, a model for the Cenozoic development of the region of SE Asia and the SW Pacific is presented and its implications are discussed, accompanied by computer animations in a variety of formats.
2,272 citations