Seismically imaged lithospheric delamination and its controls on the Mesozoic Magmatic Province in South China

Nature Communications, Journal Year: 2023, Volume and Issue: 14(1)

Published: May 11, 2023

The current lithospheric root of the South China Block has been partly removed, yet what mechanisms modified structure remain highly controversial. Here we use a new joint seismic inversion algorithm to image tabular high-velocity anomalies at depths ~90-150 km in asthenosphere beneath convergent belt between Yangtze and Cathaysia blocks that weakly connected with stable lithosphere. Based on obtained images available geochemical data, interpret these detached fast as partially destabilized lower lithosphere initially delaminated 180-170 Ma relaminated their original position after warming up mantle by now. We conclude delamination is most plausible mechanism for modification formation Mesozoic Basin Range-style magmatic province triggering adiabatic upwelling consequent extension extensive melting overlying crust.

Language: Английский

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Late Triassic to Middle Jurassic tectonic evolution of the South China Block: Geodynamic transition from the Paleo-Tethys to the Paleo-Pacific regimes

Earth-Science Reviews, Journal Year: 2023, Volume and Issue: 241, P. 104404 - 104404

Published: April 6, 2023

Language: Английский

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Testing the salinity of Cambrian to Silurian epicratonic seas

Journal of the Geological Society, Journal Year: 2024, Volume and Issue: 181(3)

Published: Feb. 19, 2024

Ancient epicratonic formations, which represent the bulk of pre-Jurassic sedimentary rocks, have been widely interpreted as marine deposits, but recently developed bulk-shale elemental proxies for palaeo-watermass salinity (i.e. B/Ga, Sr/Ba and S/TOC, where TOC is total organic carbon) shown this inference to be frequently incorrect. Here, we use these test conditions 22 representative shale marl formations early Cambrian Silurian age from five cratons (Laurentia, Avalonia, Baltica, Iran South China) in context formation-specific palaeogeographical palaeoclimatic reconstructions. Our dataset shows that around half were probably deposited under brackish or mixed brackish–marine rather than fully (as previously inferred), one them represents a freshwater facies (previously mainly on basis Cruziana traces). In most cases, development reduced-salinity can related coastal and/or humid climate belt setting formation interest was deposited. also reveals systematically low values relative modern facies), suggesting seawater Sr concentrations lower during Early Paleozoic at present. findings suggest re-evaluation characteristics many ancient necessary. Supplementary material: A supplementary figure tables are available https://doi.org/10.6084/m9.figshare.c.7063365 Thematic collection: This article part Chemical Evolution Mid-Paleozoic Earth System Biotic Response collection at: https://www.lyellcollection.org/topic/collections/chemical-evolution-of-the-mid-paleozoic-earth-system

Language: Английский

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Tectonic setting of the Youjiang giant tin belt, South China: New findings from the Pingna W-Sn deposit

Geoscience Frontiers, Journal Year: 2025, Volume and Issue: 16(2), P. 102006 - 102006

Published: Jan. 22, 2025

Language: Английский

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Global spatio-temporal variations and metallogenic diversity of karst bauxites and their tectonic, paleogeographic and paleoclimatic relationship with the Tethyan realm evolution

Earth-Science Reviews, Journal Year: 2022, Volume and Issue: 233, P. 104184 - 104184

Published: Sept. 12, 2022

Language: Английский

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“Where, when and why” for the arc-trench gap from Mesozoic Paleo-Pacific subduction zone: Sabah Triassic-Cretaceous igneous records in East Borneo

Gondwana Research, Journal Year: 2023, Volume and Issue: 117, P. 117 - 138

Published: Jan. 26, 2023

Language: Английский

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Tectonic Controls on Magmatic Tempo in an Active Continental Margin: Insights From the Early Cretaceous Syn‐Tectonic Magmatism in the Changle‐Nan’ao Belt, South China

Journal of Geophysical Research Solid Earth, Journal Year: 2023, Volume and Issue: 128(2)

Published: Feb. 1, 2023

Abstract The cause of magmatic tempo in an active plate margin remains controversial, partly due to lack structural analysis. During 130–105 Ma, the magmatism South China Block (SCB) was significantly reduced (lull) and restricted around Changle‐Nan'ao Belt (CNB) while highly (flare‐up) North China. For unveiling tectonic role on magmatism, a multidisciplinary study including field microscopic observations, magnetic fabric measurement (AMS), zircon/monazite dating conducted plutons with oriented minerals CNB. Structural analysis AMS results show clustered NE‐striking vertical foliation developed during emplacement indicating syn‐emplacement NW‐SE shortening regime. geochronology confirm that occurred Ma. Regional geologic correlation indicates collision between Dangerous Grounds‐West Philippines SCB responsible for this collected depleted zircon ε Hf(t) data suggest possible collision‐triggered slab break‐off caused syn‐collisional activity This shows lull coeval crustal regime arrival microcontinent carried by subduction slab, flare‐up extensional roll‐back retreat as evidenced Cretaceous evolution before after which is unaffected collision. continental largely underlain slabs.

Language: Английский

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Crustal architectural controls on critical metal ore systems in South China based on Hf isotopic mapping

Geology, Journal Year: 2023, Volume and Issue: 51(8), P. 738 - 742

Published: June 1, 2023

Abstract There is increasing demand for critical metals (e.g., W-Sn, Li-Be-Nb-Ta, and rare earth elements [REEs]) to sustain the transition green energy, yet it unclear what controls formation of such metal ore systems. Here, we focus on South China, which well endowed with metals, imaged its crustal architecture by zircon Hf isotopic mapping using 1096 isotope data sets 1457 samples Mesozoic granitoids silicic volcanic rocks. We demonstrate that crust isotopically heterogeneous, characterized spatial juxtaposition ancient, reworked, juvenile domains. The granite-related W-Sn-Nb-Ta REE deposits occur mainly in reworked domains, where multiple stages reworking melting events likely resulted release these into crust-derived magmas. Compared W-Sn deposits, mostly strongly blocks a input. porphyry Cu-Au are spatially confined Cu-fertilized whereas U Ag-Pb-Zn predominantly old domains at their margins. This study demonstrates importance as tool characterizing processes lead

Language: Английский

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Tungsten mineralization formed by single-pulsed magmatic fluid: Evidence from wolframite-hosted fluid inclusion from the giant Dajishan “five floor” style W-polymetallic deposit

Ore Geology Reviews, Journal Year: 2023, Volume and Issue: 157, P. 105472 - 105472

Published: May 5, 2023

The giant Dajishan W-polymetallic deposit, located in the Nanling metallogenic belt, is a typical steeply dipping wolframite-quartz vein-type deposit. From top to bottom, W ore grade highest middle and decreases towards both ends. In No. 23 vein of north group, thickness veins increases from 0.1 ∼ 0.2 m thick 517 level maximum 0.6 2.0 267 level. According "Five Floor" prospecting model, corresponds veinlet (517 m), moderate (467 417 zones (367 m). Primary wolframite-hosted fluid inclusions show homogenization temperatures display slight but explicit decrease by about 20 °C average bottom top, recording essential cooling process. phase ratios (20 30 vol% vapor proportions) salinities (6.3 10.0 wt% NaCl equiv.) are constant at all levels, indicating that neither meteoric water mixing nor boiling/immiscibility obvious during wolframite formation. fluids contain KCl as major salts, B subordinate component, with trace elements including Li, Rb, Cs, Zn, Pb, etc. significant narrow ranges K/Na (0.296 0.664), Rb/Na (0.008 0.018), Cs/Na (0.032 0.076) illustrate ore-forming come initial derived highly-evolved granitic magma. host metasandstone, muscovitization tourmalinization lead release Na, B, Al into wall rock, liberation Fe rock fluid. Wall composition data main mechanism changes contents. Preliminary calculations indicate fluid-rock interaction may contributes minor iron fluids. Combining these results, we support style mineralization formed single-pulsed magmatic vertical zonation model predominately controlled temperature, pressure, local tectonic regime, it less dependent on chemical composition.

Language: Английский

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Cassiterite U–Pb, mica 40Ar–39Ar dating and cassiterite trace-element composition of the Furong tin deposit in the Nanling Range, South China

Ore Geology Reviews, Journal Year: 2022, Volume and Issue: 143, P. 104775 - 104775

Published: Feb. 12, 2022

The Furong tin deposit (530,000 t Sn @ 0.8% Sn) is located in the southern part of Mid–Late Jurassic, multiphase, granitic Qitianling batholith Nanling Range, South China. spectrum mineralization comprises skarn, chloritized granite, greisen, and quartz vein types, which skarn type most important. Cassiterite U–Pb dating provided Tera-Wasserburg lower intercept ages 157.1 ± 1.5 Ma 156.3 for skarn-type mineralization, 158.1 1.4 158.7 1.6 granite-type 155.8 3.4 greisen-type 160.1 1.7 vein-type mineralization. These overlap with each other define a pooled weighted mean age 157.9 1.1 (2σ) ore system. Hydrothermal phlogopite from muscovite greisen yielded younger 40Ar–39Ar plateau 154.3 1.9 150.0 Ma, respectively, may reflect resetting due to post-ore fluid circulation. Distinctive cathodoluminescence textures trace-element patterns various cassiterite types indicate that four resulted pulsed ore-forming fluids changes temperature single magmatic-hydrothermal In combination geological characteristics, geochronological trace-elemental data formation different at was associated fractionated latest alkali-feldspar granite batholith, specific interactions their limestone host rocks.

Language: Английский

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