Jurassic to Neogene Quantitative Crustal Thickness Estimates In
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Two Contrasting Phanerozoic Orogenic Systems Revealed by Hafnium Isotope Data William J
ARTICLES PUBLISHED ONLINE: 17 APRIL 2011 | DOI: 10.1038/NGEO1127 Two contrasting Phanerozoic orogenic systems revealed by hafnium isotope data William J. Collins1*(, Elena A. Belousova2, Anthony I. S. Kemp1 and J. Brendan Murphy3 Two fundamentally different orogenic systems have existed on Earth throughout the Phanerozoic. Circum-Pacific accretionary orogens are the external orogenic system formed around the Pacific rim, where oceanic lithosphere semicontinuously subducts beneath continental lithosphere. In contrast, the internal orogenic system is found in Europe and Asia as the collage of collisional mountain belts, formed during the collision between continental crustal fragments. External orogenic systems form at the boundary of large underlying mantle convection cells, whereas internal orogens form within one supercell. Here we present a compilation of hafnium isotope data from zircon minerals collected from orogens worldwide. We find that the range of hafnium isotope signatures for the external orogenic system narrows and trends towards more radiogenic compositions since 550 Myr ago. By contrast, the range of signatures from the internal orogenic system broadens since 550 Myr ago. We suggest that for the external system, the lower crust and lithospheric mantle beneath the overriding continent is removed during subduction and replaced by newly formed crust, which generates the radiogenic hafnium signature when remelted. For the internal orogenic system, the lower crust and lithospheric mantle is instead eventually replaced by more continental lithosphere from a collided continental fragment. Our suggested model provides a simple basis for unravelling the global geodynamic evolution of the ancient Earth. resent-day orogens of contrasting character can be reduced to which probably began by the Early Ordovician12, and the Early two types on Earth, dominantly accretionary or dominantly Paleozoic accretionary orogens in the easternmost Altaids of Pcollisional, because only the latter are associated with Wilson Asia13. -
Initial Growth of the Northern Lhasaplano, Tibetan Plateau in the Early Late Cretaceous (Ca
hu-B35124.1 2nd pages / 1 of 14 Initial growth of the Northern Lhasaplano in the early Late Cretaceous Initial growth of the Northern Lhasaplano, Tibetan Plateau in the early Late Cretaceous (ca. 92 Ma) Wen Lai1, Xiumian Hu1,†, Eduardo Garzanti2, Gaoyuan Sun1,3, Carmala N. Garzione4, Marcelle BouDagher Fadel5, and Anlin Ma1 1State Key Laboratory of Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China 2Department of Earth and Environmental Sciences, Università di Milano-Bicocca, Milano 20126, Italy 3College of Oceanography, Hohai University, Nanjing 210098, China 4Department of Earth and Environmental Sciences, University of Rochester, Rochester, New York 14627, USA 5Department of Geological Sciences, University College London, London WC1E6BT, UK ABSTRACT INTRODUCTION Stable isotopes in lacustrine carbonates suggest that the basins surrounding the Gangdese Moun Constraining the growth of the Tibetan The Tibetan Plateau, with an average ele tains in the southern Lhasa terrane had reached Plateau in time and space is critical for test- vation of ~5000 m, is the world’s highest and an elevation >4500 m since IndiaAsia collision ing geodynamic models and climatic changes widest orogenic plateau, and exerts a major in (Ding et al., 2014). Lowtemperature thermo at the regional and global scale. The Lhasa fluence on the Asian monsoon, global climate chronology reveal that the central and northern block is a key region for unraveling the early change, and regional distribution of living spe Lhasa terranes experienced rapid to moderate history of the Tibetan Plateau. Distinct from cies (Raymo and Ruddiman, 1992; Molnar et al., cooling and exhumation between 85 and 45 Ma the underlying shallow-marine limestones, 1993; An et al., 2001; DupontNivet et al., 2007; (Hetzel et al., 2011; Rohrmann et al., 2012). -
Paleomagnetic Constraints on the Mesozoic Drift of the Lhasa Terrane (Tibet) from Gondwana to Eurasia
Paleomagnetic constraints on the Mesozoic drift of the Lhasa terrane (Tibet) from Gondwana to Eurasia Zhenyu Li1, Lin Ding1,2*, Peter C. Lippert3, Peiping Song1, Yahui Yue1, and Douwe J.J. van Hinsbergen4 1Key Laboratory of Continental Collision and Plateau Uplift (LCPU), Institute of Tibetan Plateau Research, Chinese Academy of Sciences (ITPCAS), Beijing 100101, China 2Center for Excellence in Tibetan Plateau Earth Sciences, Chinese Academy of Sciences, Beijing 100101, China 3Department of Geology and Geophysics, University of Utah, Salt Lake City, Utah 84112-9057, USA 4Department of Earth Sciences, Utrecht University, Heidelberglaan 2, 3584 CS Utrecht, Netherlands ABSTRACT Himalaya (the northernmost continental rocks The Mesozoic plate tectonic history of Gondwana-derived crustal blocks of the Tibetan derived from the Indian plate) that collided with Plateau is hotly debated, but so far, paleomagnetic constraints quantifying their paleolati- Lhasa in the Eocene along the Indus-Yarlung tude drift history remain sparse. Here, we compile existing data published mainly in Chinese suture zone (Yin and Harrison, 2000; Hu et al., literature and provide a new, high-quality, well-dated paleomagnetic pole from the ca. 180 2015; Huang et al., 2015). Ma Sangri Group volcanic rocks of the Lhasa terrane that yields a paleolatitude of 3.7°S Most authors describe an ideal Wilson-cycle ± 3.4°. This new pole confirms a trend in the data that suggests that Lhasa drifted away scenario, wherein the blocks of the Tibetan Pla- from Gondwana in Late Triassic time, instead of Permian time as widely perceived. A total teau all drifted from India in Paleozoic to Meso- northward drift of ~4500 km between ca. -
Post-Collisional Potassic Magmatism in the Eastern Lhasa Terrane, South Tibet: Products of Partial Melting of Mélanges in a Continental Subduction Channel
Gondwana Research 41 (2017) 9–28 Contents lists available at ScienceDirect Gondwana Research journal homepage: www.elsevier.com/locate/gr Post-collisional potassic magmatism in the eastern Lhasa terrane, South Tibet: Products of partial melting of mélanges in a continental subduction channel Lihong Zhang a,b, Zhengfu Guo a,⁎,MaoliangZhanga,b, Zhihui Cheng a,b, Yutao Sun a,b a Key Laboratory of Cenozoic Geology and Environment, Institute of Geology and Geophysics, Chinese Academy of Sciences, Beijing 100029, China b University of Chinese Academy of Sciences, Beijing 100049, China article info abstract Article history: Post-collisional, potassic magmatic rocks widely distributed in the eastern Lhasa terrane provide significant Received 29 May 2015 information for comprehensive understanding of geodynamic processes of northward subduction of the Indian Received in revised form 18 October 2015 lithosphere and uplift of the Tibetan Plateau. A combined dataset of whole-rock major and trace elements, Accepted 3 November 2015 Sr–Nd–Pb isotopes, and in situ zircon U–Pb dating and Hf–O isotopic analyses are presented for the Yangying Available online 23 December 2015 potassic volcanic rocks (YPVR) in the eastern part of the Lhasa terrane, South Tibet. These volcanic rocks consist of trachytes, which are characterized by high K O(5.46–9.30 wt.%), SiO (61.34–68.62 wt.%) and Al O (15.06– Keywords: 2 2 2 3 – – Post-collisional potassic magmatism 17.36 wt.%), and relatively low MgO (0.47 2.80 wt.%) and FeOt (1.70 4.90 wt.%). Chondrite-normalized rare Zircon U–Pb dating earth elements (REE) patterns display clearly negative Eu anomalies. -
Introduction to Himalayan Tectonics: a Modern Synthesis
Downloaded from http://sp.lyellcollection.org/ at Kingston University on January 3, 2020 Introduction to Himalayan tectonics: a modern synthesis MICHAEL P. SEARLE1* & PETER J. TRELOAR2 1Department of Earth Sciences, University of Oxford, Oxford OX1 3AN, UK 2School of the Natural and Built Environment, Kingston University, Penrhyn Road, Kingston-upon-Thames, Surrey KT1 2EE, UK MPS, 0000-0001-6904-6398 *Correspondence: [email protected] The Himalaya resulted from collision of the Indian widespread migmatization and mid-crustal melting plate with Asia and are well known as the highest, during the Oligocene–Mid-Miocene. The age of the youngest and one of the best studied continental col- abundant leucogranite sills and dykes along the top lision orogenic belts. They are frequently used as the of the GHS, beneath the STD, is concomitant with type example of a continental collision orogenic belt the sillimanite-grade metamorphic event. The GHS in studies of older Phanerozoic orogenic belts. The metamorphism is all part of one continuum of crustal beauty of the Himalaya is that, on a broad scale they thickening and shortening, increasing pressure and form a relatively simple orogenic belt. The major temperature following a standard clockwise Pressure- structural divisions, the Indus–(Yarlung Tsangpo) Temperature-Time (PTt) path. Decompression suture zone, the Tethyan Himalaya sedimentary melting peaked with widespread partial melting and units, Greater Himalaya Sequence (GHS) metamor- formation of migmatites and leucogranites along the phic rocks, the Lesser Himalaya fold-and-thrust highest peaks of the Himalaya. Structural mapping belt and the Sub-Himalaya Siwalik molasse basin and timing constraints suggest the large-scale are present along the entire 2000 km length of the southward extrusion of a partially melted layer of Himalaya (Figs 1 & 2). -
Mid-Cretaceous Thick Carbonate Accumulation in Northern Lhasa (Tibet): Eustatic Vs
Mid-Cretaceous thick carbonate accumulation in Northern Lhasa (Tibet): eustatic vs. tectonic control? Yiwei Xu1, Xiumian Hu1,†, Eduardo Garzanti2, Marcelle BouDagher-Fadel3, Gaoyuan Sun4, Wen Lai1, and Shijie Zhang5 1 State Key Laboratory of Mineral Deposits Research, School of Earth Sciences and Engineering, Nanjing University, Nanjing 210023, China 2 Department of Earth and Environmental Sciences, Università di Milano-Bicocca, Milano 20126, Italy 3 Department of Earth Sciences, University College London, Gower Street, London, WC1E 6BT, UK 4 College of Oceanography, Hohai University, Nanjing 210098, China 5 School of Tourism, Henan Normal University, Xinxiang 453007, China ABSTRACT INTRODUCTION Moreover, their thickness does not exceed a few hundreds of meters, because carbonate Widespread accumulation of thick car- The Lhasa terrane, lying between the In- production is hampered in orogenic settings bonates is not typical of orogenic settings. dus–Yarlung suture to the south and the Ban- where tectonic uplift and erosion produce During the mid-Cretaceous, near the Ban- gong suture to the north (Fig. 1A), is the latest abundant terrigenous detritus (Wilson, 1975; gong suture in the northern Lhasa terrane, microcontinent accreted to Asia before colli- Dorobek, 1995). However, in a few cases (e.g., the shallow-marine carbonates of the Lang- sion between the Indian and Asian continental the Papua–New Guinea foreland basin) car- shan Formation, reaching a thickness up to margins. The timing of collision between the bonate thickness may reach 1.2 km (Sinclair, ∼1 km, accumulated in an epicontinental Qiangtang and Lhasa terranes along the Ban- 1997). Finally, carbonates generally occur only seaway over a modern area of 132 × 103 km2, gong suture (Fig. -
1 Rapid Early Miocene Exhumation of the Ladakh Batholith, Western
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by University of Strathclyde Institutional Repository Rapid Early Miocene exhumation of the Ladakh Batholith, western Himalaya. Linda A. Kirstein 1, Hugh Sinclair 1, Finlay M. Stuart 2, Katherine Dobson 2, 3 1School of GeoSciences, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JW, U.K. 2Isotope Geosciences Unit, SUERC, Rankine Avenue, East Kilbride, Glasgow, G75 0QF, U.K. 3Department of Geographical and Earth Sciences, University of Glasgow, Lilybank Gardens, Glasgow, G12 8QQ UK. ABSTRACT Zircon and apatite (U-Th)/He, and apatite fission track age data record a major rapid cooling event of the Ladakh Batholith of northwest India at c. 22 Ma. Combining the thermochronometric data with structural evidence it is proposed that exhumation was due to south-directed overthrusting of the Batholith. This thrust is potentially an extension of the Gangdese Thrust which accommodates underthrusting of the Gangdese Batholith in southern Tibet. The rapid exhumation recorded in Ladakh is contemporaneous with exhumation of the High Himalaya. This focused denudation and structural shortening north of the Indus Suture Zone in early Miocene times implies that the actively deforming and eroding Himalayan thrust wedge extended further north than channel flow models currently predict. 1 INTRODUCTION The Himalayan mountain chain is bordered to the north by a line of arc-derived batholiths known as the Trans-Himalayan Plutonic Belt that stretch 2500 km from Afghanistan in the west to Bhutan (Honneger et al., 1982). Prior to collision at approximately 55 Ma, there was extensive oceanic subduction northward beneath the Plutonic belt now preserved as slivers of ophiolite in the Zanskar Range (Searle et al., 1997; Makovsky et al., 1999). -
Himalaya - Southern-Tibet: the Typical Continent-Continent Collision Orogen
237 Himalaya - Southern-Tibet: the typical continent-continent collision orogen When an oceanic plate is subducted beneath a continental lithosphere, an Andean mountain range develops on the edge of the continent. If the subducting plate also contains some continental lithosphere, plate convergence eventually brings both continents into juxtaposition. While the oceanic lithosphere is relatively dense and sinks into the asthenosphere, the greater sialic content of the continental lithosphere ascribes positive buoyancy in the asthenosphere, which hinders the continental lithosphere to be subducted any great distance. Consequently, a continental lithosphere arriving at a trench will confront the overriding continent. Rapid relative convergence is halted and crustal shortening forms a collision mountain range. The plane marking the locus of collision is a suture, which usually preserves slivers of the oceanic lithosphere that formerly separated the continents, known as ophiolites. The collision between the Indian subcontinent and what is now Tibet began in the Eocene. It involved and still involves north-south convergence throughout southern Tibet and the Himalayas. This youthful mountain area is the type example for studies of continental collision processes. The Himalayas Location The Himalayas form a nearly 3000 km long, 250-350 km wide range between India to the south and the huge Tibetan plateau, with a mean elevation of 5000 m, to the north. The Himalayan mountain belt has a relatively simple, arcuate, and cylindrical geometry over most of its length and terminates at both ends in nearly transverse syntaxes, i.e. areas where orogenic structures turn sharply about a vertical axis. Both syntaxes are named after the main peaks that tower above them, the Namche Barwa (7756 m) to the east and the Nanga Parbat (8138 m) to the west, in Pakistan. -
Late Paleozoic and Mesozoic Evolution of the Lhasa Terrane in the Xainza MARK Area of Southern Tibet
Tectonophysics 721 (2017) 415–434 Contents lists available at ScienceDirect Tectonophysics journal homepage: www.elsevier.com/locate/tecto Late Paleozoic and Mesozoic evolution of the Lhasa Terrane in the Xainza MARK area of southern Tibet ⁎ Suoya Fana,b, , Lin Dinga, Michael A. Murphyb, Wei Yaoa, An Yinc a Key Laboratory of Continental Collision and Plateau Uplift, Institute of Tibetan Plateau Research, Chinese Academy of Sciences, Beijing 100101, China b Department of Earth and Atmospheric Sciences, University of Houston, Houston, TX 77204, USA c Department of Earth, Planetary, and Space Sciences, University of California, Los Angeles, CA 90095-1567, USA ARTICLE INFO ABSTRACT Keywords: Models for the Mesozoic growth of the Tibetan plateau describe closure of the Bangong Ocean resulting in Lhasa terrane accretion of the Lhasa terrane to the Qiangtang terrane along the Bangong-Nuijiang suture zone (BNSZ). Shortening However, a more complex history is suggested by studies of ophiolitic melanges south of the BNSZ “within” the Foreland basin Lhasa terrane. One such mélange belt is the Shiquanhe-Namu Co mélange zone (SNMZ) that is coincident with Suture zone the Geren Co-Namu Co thrust (GNT). To better understand the structure, age, and provenance of rocks exposed Provenance along the SNMZ we conducted geologic mapping, sandstone petrography, and U-Pb zircon geochronology of Geochronology rocks straddling the SNMZ. The GNT is north-directed and places Paleozoic strata against the Yongzhu ophiolite and Cretaceous strata along strike. A gabbro in the Yongzhu ophiolite yielded a U-Pb zircon age of 153 Ma. Detrital zircon age data from Permian rocks in the hanging wall suggests that the Lhasa terrane has affinity with the Himalaya and Qiangtang, rather than northwest Australia. -
Lhasa Terrane in Southern Tibet Came from Australia
Lhasa terrane in southern Tibet came from Australia Di-Cheng Zhu1*, Zhi-Dan Zhao1, Yaoling Niu1,2,3, Yildirim Dilek4, and Xuan-Xue Mo1 1State Key Laboratory of Geological Processes and Mineral Resources, and School of Earth Science and Resources, China University of Geosciences, Beijing 100083, China 2School of Earth Sciences, Lanzhou University, Lanzhou 730000, China 3Department of Earth Sciences, Durham University, Durham DH1 3LE, UK 4Department of Geology, Miami University, Oxford, Ohio 45056, USA ABSTRACT REGIONAL GEOLOGY AND DETRITAL The U-Pb age and Hf isotope data on detrital zircons from Paleozoic metasedimentary rocks ZIRCON ANALYSES ε in the Lhasa terrane (Tibet) defi ne a distinctive age population of ca. 1170 Ma with Hf(t) values The Lhasa terrane is one of the three large identical to the coeval detrital zircons from Western Australia, but those from the western east-west−trending tectonic belts in the Tibetan Qiangtang and Tethyan Himalaya terranes defi ne an age population of ca. 950 Ma with a similar Plateau. It is located between the Qiangtang ε Hf(t) range. The ca. 1170 Ma detrital zircons in the Lhasa terrane were most likely derived from and Tethyan Himalayan terranes, bounded by the Albany-Fraser belt in southwest Australia, whereas the ca. 950 Ma detrital zircons from both the Bangong-Nujiang suture zone to the north the western Qiangtang and Tethyan Himalaya terranes might have been sourced from the High and the Indus–Yarlung Zangbo suture zone to Himalaya to the south. Such detrital zircon connections enable us to propose that the Lhasa the south, respectively (Fig. -
Microcontinent Subduction and S-Type Volcanism Prior to India–Asia Collision
www.nature.com/scientificreports OPEN Microcontinent subduction and S‑type volcanism prior to India–Asia collision Zongyao Yang1,2, Juxing Tang1,2*, M. Santosh3,4, Xiaoyan Zhao1*, Xinghai Lang5, Ying Wang1, Shuai Ding5 & Fengqin Ran5 Continental crust has long been considered too buoyant to be subducted beneath another continent, although geophysical evidence in collision zones predict continental crust subduction. This is particularly signifcant where upper continental crust is detached allowing the lower continental crust to subduct, albeit the mechanism of such subduction and recycling of the upper continental crust remain poorly understood. Here, we investigate Paleocene S‑type magmatic and volcanic rocks from the Linzizong volcanic succession in the southern Lhasa block of Tibet. These rocks exhibit highly enriched 87Sr/86Sr, 207Pb/206Pb and 208Pb/206Pb together with depleted 143Nd/144Nd isotope ratios. The geochemical and isotopic features of these rocks are consistent with those of modern upper continental crust. We conclude that these Paleocene S‑type volcanic and magmatic rocks originated from the melting of the upper continental crust from microcontinent subduction during the late stage of India–Asia convergence. Te amalgamation of the Indian and Asian lithospheric plates and the construction of the Himalayan–Tibetan orogens mark one of the most prominent collisional events on the globe 1,2. Te rise of the Qinghai–Tibet Plateau as the highest plateau in the world with an average elevation of around 3000 m is a remarkable outcome of the India–Asia collision along the Indus–Yarlung suture zone (IYSZ)3 (Fig. 1). Te Linzizong volcanic succession (LVS) and the coeval intrusive rocks in southern Tibet, which cover more than 50% of the Gangdese Belt extend- ing E–W for more than 1200 km (Fig. -
Zircon U–Pb Geochronology and Hf Isotopic Constraints on Petrogenesis of the Gangdese Batholith, Southern Tibet
Chemical Geology 262 (2009) 229–245 Contents lists available at ScienceDirect Chemical Geology journal homepage: www.elsevier.com/locate/chemgeo Zircon U–Pb geochronology and Hf isotopic constraints on petrogenesis of the Gangdese batholith, southern Tibet Wei-Qiang Ji a, Fu-Yuan Wu a,⁎, Sun-Lin Chung b, Jin-Xiang Li a, Chuan-Zhou Liu a a State Key Laboratory of Lithospheric Evolution, Institute of Geology and Geophysics, Chinese Academy of Sciences, P.O. Box 9825, Beijing 100029, China b Department of Geosciences, National Taiwan University, Taipei 106, Taiwan article info abstract Article history: During the Mesozoic–Cenozoic, northward Neotethyan subduction and subsequent India–Asia collision gave Received 16 June 2008 rise to the extensive Transhimalayan magmatism that stretches from Burma and western Yunnan through Received in revised form 16 January 2009 southern Tibet to the Ladakh and Kohistan complexes. To understand the age distribution and petrogenesis of Accepted 20 January 2009 the Gangdese batholith, the largest intrusive exposure along the Transhimalayan magmatic belt, fifty granitic Editor: R.L. Rudnick samples were selected for in situ zircon U–Pb and Hf isotopic analyses. The U–Pb data suggest four discrete stages of magmatic activity, i.e., ~205–152, ~ 109–80, ~65–41 and ~33–13 Ma, respectively, with the 65– Keywords: 41 Ma stage being the most prominent. The Hf isotopic data indicate that the Gangdese batholith is U–Pb age overwhelmed by positive εHf(t) values, which are comparable to those of the Kohistan–Ladakh batholiths in Hf isotope the west but differ markedly from those of the Chayu–Burma batholiths in the east.