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Ultra-hot Mesoproterozoic evolution of intracontinental central Australia

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Geoscience Frontiers 2015年第1期6卷 23-37页

作者： Weronika Gorczyk Hugh Smithies Fawna Korhonen Heather Howard Raphael Quentin De Gromard Center for Exploration Targeting School of Earth and EnvironmentThe University of Western Australia geological survey of western Australia

The Musgrave Province developed at the nexus of the North, West and South Australian cratons and its Mesoproterozoic evolution incorporates a 100 Ma period of ultra-high temperature （UHT） meta- morphism from ca. 1220 to ca. 1120 Ma. This was accompanied by high-temperature A-type granitic magmatism over an 80 Ma period, sourced in part from mantle-derived components and emplaced as a series of pulsed events that also coincide with peaks in UHT metamorphism. The tectonic setting for this thermal event （the Musgrave Orogeny） is thought to have been intracontinental and the lithospheric architecture of the region is suggested to have had a major influence on the thermal evolution. We use a series of two dimensional, fully coupled thermo-mechanical-petrological numerical models to investi- gate the plausibility of initiating and prolonging UHT conditions under model setup conditions appro- priate to the inferred tectonic setting and lithospheric architecture of the Musgrave Province. The results support the inferred tectonic framework for the Musgrave Orogeny, predicting periods of UHT meta- morphism of up to 70 Ma, accompanied by thin crust and extensive magmatism derived from both crustal and mantle sources. The results also appear to be critically dependent upon the specific location of the Mus^rave Province. constrained between thicker cratonic masses.

关键词： Ultra-high temperature (UHT) metamorphism Numerical modeling Intra-continental orogeny

Origin of the Newly Discovered Zhunuo Porphyry Cu-Mo-Au Deposit in the western Part of the Gangdese Porphyry Copper Belt in the Southern Tibetan Plateau,SW China

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Acta Geologica Sinica(English Edition) 2017年第1期91卷 109-134页

作者： HUANG Yong LI Guangming DING Jun DAI Jie YAN Guoqiang DONG Suiliang HUANG Hanxiao Chengdu Center China Geological Survey Tianjin Center China Geological Survey

The newly discovered Zhunuo porphyry Cu-Mo-Au deposit is located in the western part of the Gangdese porphyry copper belt in southern Tibet, SW China. The granitoid plutons in the Zhunuo region are composed of quartz diorite porphyry, diorite porphyry, granodiorite porphyry, biotite monzogranite and quartz porphyry. The quartz diorite porphyry yielded zircon U-Pb ages of 51.9±0.7 Ma（Eocene） using LA-ICP-MS, whereas the diorite porphyry, granodiorite porphyry, biotite monzogranite and quartz porphyry yielded ages ranging from 16.2±0.2 to 14.0±0.2 Ma（Miocene）. CuMo-Au mineralization is mainly hosted in the Miocene granodiorite porphyry. Samples from all granitoid plutons have geochemical compositions consistent with high-K calc-alkaline series magmatism. The samples display highly fractionated light rare-earth element（REE） distributions and heavy REE distributions with weakly negative Eu anomalies on chondrite-normalized REE patterns. The trace element distributions exhibit positive anomalies for large-ion lithophile elements（Rb, K, U, Th and Pb） and negative anomalies for high-field-strength elements（Nb and Ti） relative to primitive mantlenormalized values. The Eocene quartz diorite porphyry yielded εNd（t） values ranging from-3.6 to-5.2,（-（87）Sr/-（86）Sr）i values in the range 0.7046–0.7063 and initial radiogenic Pb isotopic compositions with ranges of 18.599–18.657 -（206）Pb/-（204）Pb, 15.642–15.673 -（207）Pb/-（204）Pb and 38.956–39.199 -（208）Pb/-（204）Pb. In contrast, the Miocene granitoid plutons yielded ε（Nd）（t） values ranging from-6.1 to-7.3 and（87Sr/86Sr）i values in the range 0.7071–0.7078 with similar Pb isotopic compositions to the Eocene quart diorite. The Sr-Nd-Pb isotopic compositions of the rocks are consistent with formation from magma containing a component of remelted ancient crust. Zircon grains from the Eocene quartz diorite have ε（Hf）（t） values ranging from-5.2 to ＋0.9 and two-stage Hf model ages ranging from 1.07 to 1.46 Ga, while zircon grains from the M

关键词： Zircon U-Pb dating Sr-Nd-Pb-Hf isotope Zhunuo porphyry Cu-Mo-Au deposit Gangdese porphyry copper belt

Discussing the Oil-Control Effects of the North Latitudinal 38° Belt in Central Part of the Ordos Basin

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Acta Geologica Sinica(English Edition) 2015年第2期89卷 687-688页

作者： MA Licheng ZHANG Linyan WANG Zongxui ZHOU Xingui LI Chunlin CHEN Xiao Institute of Geomechanics Chinese Academy of Geological Sciences Key Lab of Shale Oil and Gas geological survey Chinese Academy of Geological Sciences The Oil and Gas survey China Geological Survey

The Ordos Basin in the western part of the North China Craton is commonly believed to be a multi-controlled oil- bearing basin. It is bounded by the Xing＇an--Mongolian Orogen to the north, the Qingling Orogen to the south, the Lüliang mountain to the east and the Helanshan--Liupanshan mountain belt to the west. The interpretation of geophysical data reveals a latitudinal （38°） fault belt in the centre of the Ordos Basin, which controls the hydrocarbon generation, migration and accumulation in the basin. This study attempts to investigate this belt from outcrops and indicates a structurally controlled system of migration fairway within the fault belt.

关键词： Belt in Central Part of the Ordos Basin Discussing the Oil-Control Effects of the North Latitudinal 38

Updated Digital Map of Mafic Dyke Swarms and Large Igneous Provinces in western Australia

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Acta Geologica Sinica(English Edition) 2016年第S1期90卷 13-14页

作者： Michael T.D.WINGATE David Mc B.MARTIN geological survey of western Australia

Since 1894,the geological survey of western Australia(GSWA)has released 14 versions of the‘geological Map of western Australia’.The latest in this series,published in December 2015,is the first bedrock geology map

关键词： Updated Digital Map of Mafic Dyke Swarms and Large Igneous Provinces in western Australia

Towards the Triassic Configuration of western Paleotethys

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Journal of Earth Science 2022年第6期33卷 1494-1512页

作者： Darko Spahić Department of geological Mapping Geological Survey of Serbia11000BelgradeSerbia

The tectono-paleogeograhic inheritance of barely documented Paleotethyan influence on the Southern Carpathian-Balkan belt is herein reappraised to highlight complex processes occurring along an alternative branched configuration of Triassic fossil subduction zone *** absence of Paleotethyan oceanic accretionary complexes,and the unavailability of rocks returned from poorly traceable Triassic subduction zones allow no conventional insights into its internal *** contrast,the adjoining Dinarides and investigated western Southern Carpathian-Balkan belt contain metamorphic rocks ejected from the precursory Late Paleozoic Paleotethyan active *** inventory and reappraisal of Variscan and Cimmerian imprints,far-field effects place the peri-Moesian Southern Carpathian-Balkan belt into the overriding plate position above the Triassic Paleotethyan active *** Permian–Early Triassic dragging of underlying Paleotethyan crustal material beneath external segments of the continental margin is contemporaneous with the onset and formation of several episutural back-arc *** include the Maliac Ocean with a here introduced NNW-SSE striking Lower–Middle Triassic marginal shallow-water clastic-carbonate basin of Getic Unit(Gornjak nappe)that is spatially in line with the“Volvi-Therma”western Rhodope aborted Triassic rift *** carbonate platform deposition was interrupted by a change in the geodynamic regime at the end of the Middle Triassic(inducing mild compressional deformations and the regional uplift resulting in missing of Upper Triassic sediments).The constraints on the investigated sequences yield that the lagged Paleotethyan closure in the Balkan sector occurred during the late Ladinian-Carnian interval.

关键词： Paleotethys Eocimmerian docking Serbo-Macedonian Unit Mali Jastrebac granitoids Gornjak sequence Upper Triassic unconformity geodynamics

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Early Permian–Late Triassic Magmatism in the Tuotuohe Region of the Qinghai–Tibet Plateau: Constraints on the Tectonic evolution of the western Segment of the Jinshajiang Suture

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Acta Geologica Sinica(English Edition) 2014年第2期88卷 498-516页

作者： QIAN Ye SUN Fengyue LI Bile LI Shijin ZHAO Junwei College of Earth Sciences Jilin University Qinghai geological survey No.5 geological and Mineral survey Institute of Qinghai Province

In this paper we present new zircon U-Pb ages,whole-rock major and trace element analyses,and zircon Hf isotopic data for magmatic rocks in the Tuotuohe region of the western segment of the Jinshajiang *** aim is to constrain the Early Permian-Late Triassic tectonic evolution of the *** from the magmatic rocks of the Tuotuohe region are euhedralsubhedral in shape and display fine-scale oscillatory zoning as well as high Th/U ratios （0.4-4.6）,indicating a magmatic *** zircon U-Pb ages obtained using LA-ICP-MS are 281 ± 1 Ma,258 ± 1 Ma,244 ± 1 Ma,and 216 ± 1 Ma,which indicate magmatism in the Early Permian-Late Triassic.A diorite from Bashihubei （BSHN） has SiO2 =57.18-59.97 wt％,Al2O3=15.70-16.53 wt％,and total alkalis （Na2O ＋ K2O） =4.46-6.34 wt％,typical of calc-alkaline and metaluminous series.A gabbro from Bashibadaoban （BSBDB） belongs to the alkaline series,and is poor in SiO2 （45.46-54.03 wt％） but rich in Al2O3 （16.19-17.39 wt％） and total alkalis （Na2O ＋ K2O =5.48-6.26 wt％）.The BSHN diorite and the BSBDB gabbro both display an enrichment of LREEs and LILEs and depletion of HFSEs,and they have no obvious Eu anomaly; they have relatively low MgO contents （2.54-4.93 wt％）,Mg# values of 43 to 52,and low Cr and Ni contents （8.07-33.6 ppm and 4.41-14.2 ppm,respectively）,indicating they differentiated from primitive mantle *** have low Nb/U,Ta/ U,and Ce/Pb ratios （1.3-9.6,0.2-0.8,and 0.1-18.1,respectively）,and their initial Hf isotopic ratios range from ＋9.6 to ＋16.9 （BSHN diorite） and ＋6.5 to ＋12.6 （BSBDB gabbro）,suggesting their primary magmas were derived mainly from the partial melting of a mantle wedge that had been metasomatized by subduction *** all the new data together,we conclude that the western and eastern segment of the Jinshajiang suture regions underwent identical processes of evolution in the Early Permian-Late Triassic：oceanic crust subduction before the Early Permian,continental collision during the Early-Middle T

关键词： zircon U-Pb chronology zircon Hf isotopes geochemistry tectonic setting Tuotuohe region Jinshajiang suture Qinghai-Tibet Plateau

A Newly Discovered Oil-bearing Mesoproterozoic Erathem within the Niu D1 Well, Liaoxi Depression, Yanliao Faulted Depression Zone, NE China

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Acta Geologica Sinica(English Edition) 2020年第1期94卷 202-203页

作者： SUN Qiushi GAO Xiaoyong ZONG Wenming SUN Shouliang ZHANG Tao XIAO Fei LI Yongfei SHI Lei Shenyang Center of geological survey China Geological Survey(CGS)/Northeast China Center for Geoscience InnovationShenyang 110034China

Objective The Yanshan Fold Belt is located within the northern margin of the North China platform and contains welldeveloped and widespread Neoproterozoic and Mesoproterozoic sedimentary units with a total thickness of up to 9000 *** studies identified many oil seedlings as well as asphalt and ancient hydrocarbon reservoirs in Northern Hebei depression and western Liaoning *** research indicates that the Mesoproterozoic and Neoproterozoic sedimentary units are ideally suited for the formation of significant oil and gas *** Niu D1 well was drilled by the China geological survey(CGS)in the Niuyingzi area and intercepted oil immersions and oil-and gas-bearing units within a limestone reservoir in the middle Proterozoic Gaoyuzhuang Formation(Fig.1).This study presents new biomarker compound and carbon isotope data that indicate that the oil within this formation was derived from hydrocarbon source rocks of the Hongshuizhuang Formation,part of the Mesoproterozoic Jixian Series,and the reservoir type is overthrust fault fractured anticline hydrocarbon *** oil reservoir within the Gaoyuzhuang Formation limestone might represent the oldest oil reservoir discovered to date within the Yanliao faulted depression zone.

关键词： NE China A Newly Discovered Oil-bearing Mesoproterozoic Erathem within the Niu D1 Well Yanliao Faulted Depression Zone Liaoxi Depression

Stable isotope paleohydrology and chemostratigraphy of the Albian Wayan Formation from the wedge-top depozone,North American western Interior Basin

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Science China Earth Sciences 2017年第1期60卷 44-57页

作者： Jeffrey B.ROSS Greg A.LUDVIGSON Andreas MOLLER Luis A.GONZALEZ J.D.WALKER Department of Geology University of Kansas Kansas geological survey University of Kansas

Understanding of the role of atmospheric moisture and heat transport in the climate system of the Cretaceous greenhouse world represents a major challenge in Earth system science. Stable isotopic paleohydrologic data from mid-Cretaceous paleosols in North America, from paleoequatorial to paleoArctic latitudes, have been used to constrain the oxygen isotope mass balance of the Albian hydrologic cycle. Over the range from 40°-50°N paleolatitude, sideritic paleosols predominate, indicating paleoenvironments with positive precipitation-evaporation （P-E） balances. Local exceptions occur on leeward side of the Sevier Orogen, where calcic paleosols in the wedge-top depozone record paleoenvironments with negative P-E balances in the orographic rain shadow. Stratigraphic sections in the Wayan Formation of Idaho （WF） were sampled from the wedge-top depozone. The units consist of stacked m-scale mudstone paleosols separated by m-scale sandstone-siltstone beds. Sections were sampled for organic carbon isotope profiles, and B-horizons from 6 well-developed paleosols were sampled for detrital zircons to determine maximum depositional ages. The first of these from the WF has produced a U-Pb concordia age of 101.0±1.1 Ma. This same WF section has produced a stratigraphic trend of upwardly decreasing δ18C values ranging from -24‰ upwards to -27‰ VPDB, suggesting correlation to the late Albian C15 C-isotope segment. Pedogenic carbonates from the WF principally consist of micritic calcite, with carbon-oxygen isotope values that array along meteoric calcite lines （MCLs） with δ18O values that range from -9.47‰ up to -8.39‰ VPDB. At approximately 42°N paleolatitude, these MCL values produce calculated paleoprecipitation values of-8.12‰ to -7.04‰ VSMOW, a range that is consistent with the estimates produced from other proxies at the same paleolatitudes across North America. These results indicate that despite the orographic rain shadow effect, the processes of meridional atmospheric moist

关键词： Cretaceous Paleoclimate Wayan Formation Pedogenic carbonates Geochronology

Zircon Dating and geological Implications of Granitic Gneiss in the Metamorphic Zone of Gaoligong Mountains in western Yunnan, China

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Acta Geologica Sinica(English Edition) 2013年第2期87卷 440-453页

作者： TAN Xiaohong ZHAO Bo LI Xikang XU Zhangbao ZHANG Zhen Institute of geological survey of Yunnan Province Institute of Mineral Resources Chinese Academy of Geological Sciences

The general classification of intermediate-acid intrusive rocks in the metamorphic zone of Gaoligong Mountains as one of the metamorphic terranes of Proterozoic Gaoligong Mountains is problematic regarding the intrusion stage and age, as well as the subsequent metamorphism and deformation. In this study, we investigated granitic gneiss in the metamorphic zone of Gaoligong Mountains based on the 1：50,000 regional geological survey of Qushi Street （2011-2013） and SHRIMP U-Pb zircon geochronology. Results showed that the SHRIMP U-Pb zircon dating of granitic gneiss ranged from 163.5±5.7 Ma to 74.0±2.0 Ma. Thus, the granitic gneiss was grouped into orthometamorphic rocks （metamorphic intrusions）. The dating data of granite rocks associated with intense metamorphism and deformation were divided into three groups, 163.5±5.7 to 162.3±3.1 Ma, 132.2-101.0 Ma and 99.4±3.5-74.0±2.0 Ma, which respectively represented three independent geologic events including an important magma intrusion with superimposed metamorphic effects in the late Middle Jurassic, regional dynamic metamorphism and superimposed reformation of fluid action in the early Cretaceous, and dynamic metamorphism dominated by ductile shear and metamorphism starting from the late Cretaceous.

关键词： Metamorphic zone granitic gneiss U-Pb zircon age Gaoligong Mountains western Yunnan