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Review on the Tectonic Terranes Associated with Metallogenic Zones in southeast Asia

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Journal of Earth Science 2019年第1期30卷 1-19页

作者： Zhengwei Zhang Qiao Shu Xiaoyong Yang Chengquan Wu Chaofei Zheng Jinhong Xu State Key Laboratory of Ore Deposit Geochemistry Institute of Geochemistry Chinese Academy of Sciences CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China University of Chinese Academy of Sciences

The paper presents an overview of the relationships between the interior structures of tectonic terranes and the distribution of tectonic-metallogenic zones in southeast Asia. Episodic tectonic activities occurred in this archipelagic area, generating metallogenic belts in multi-terranes. Since the Late Paleozoic, opening and closure of the Paleotethys and Neotethys led to multiple suture zones between different blocks, mainly between the Indochina terrane, the Nambung terrane, the Sibumasu terrane and the West Myanmar terrane. During the Mesozoic to Cenozoic, the formation of accreted terranes and their related islands was caused by subduction and collision processes between the Pacific and Australian plates toward the Eurasian Continent, forming Sundaland and its affiliated islands, the Philippines and its subsidiary islands, the Papua New Guinea terrane and its related islands and the Sunda epicontinental arc system. Within the margin of terranes resulted in the structural transfer zones, their secondary tectonic units can be divided into island arc belts, back-arc basins, suture zones, marginal fold belts and orogenic belts. The metallogenic assemblages are mainly distributed within these structural zones of the terranes. According to the relationship between these tectonic units and the distribution of mineral resources, the tectonic-metallogenic belts can be divided into 24 metallogenic belts in southeast Asia. They are characterized by a diversity and frequency of metallogenic material combination which is likely to reflect the complexity of the material distribution during mineralization processes, mostly by the structural transformation during the dissociation-convergence process between multiple terranes. Therefore, the formation of ore deposits was not only restricted by the evolution(opening and closure) of Paleo-and Neotethys, but may also be controlled by the interaction of the terranes with different tectonic attributes which provided multiple sources

关键词： southeast Asia terrane groups metallogenetic belt subduction-collision Tethys

Age and metal source of orogenic gold deposits in southeast Guizhou Province, China: Constraints from Re-Os and He-Ar isotopic evidence

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Geoscience Frontiers 2019年第2期10卷 581-593页

作者： Jiasheng Wang Hanjie Wen Chao Li Jinrang Zhang Wei Ding Southwest Institute of Geological Survey Kunming University of Science and Technology State Key Laboratory of Ore Deposit Geochemistry Institute of GeochemistryChinese Academy of Sciences National Research Center for Geoanalysis

The orogenic gold deposits in southeast Guizhou are an important component of the Xuefeng polymetallic ore belt and have significant exploration potential, but geochronology research on these gold deposits is scarce. Therefore, the ore genetic models are poorly constrained and remain unclear. In the present study, two important deposits(Pingqiu and Jinjing) are investigated, including combined Re-Os dating and the He-Ar isotope study of auriferous arsenopyrites. It is found that the arsenopyrites from the Pingqiu gold deposit yielded an isochron age of 400 ± 24 Ma,with an initial ^(187)Os/^(188)Os ratio of 1.24 ± 0.57(MSWD = 0.96). An identical isochron age of 400 ± 11 Ma with an initial ^(187)Os/^(188)Os ratio of 1.55 ± 0.14(MSWD = 0.34) was obtained from the Jinjing deposit. These ages correspond to the regional Caledonian orogeny and are interpreted to represent the age of the main stage ore. Both initial ^(187)Os ratios suggest that the Os was derived from crustal rocks. Combined with previous rare earth element(REE), trace elements, Nd-Sr-S-Pb isotope studies on scheelite, inclusion fluids with other residues of gangue quartz, and sulfides from other gold deposits in the region, it is suggested that the ore metals from Pingqiu and Jinjing were sourced from the Xiajiang Group. The He and Ar isotopes of arsenopyrites are characterized by ~3 He/~4 He ratios ranging from 5.3 × 10^(-4) Ra to 2.5 × 10^(-2) Ra(Ra = 1.4 × 10^(-6), the ~3 He/~4 He ratio of air), 40 Ar=/~4 He ratios from 0.64 × 10^(-2) to 15.39×10^(-2), and ^(40)Ar/^(36)Ar ratios from 633.2 to 6582.0. Those noble gas isotopic compositions of fluid inclusions also support a crustal source origin,evidenced by the Os isotope. Meanwhile, recent noble gas studies suggest that the amount of in situ radiogenic ~4 He generated should not be ignored, even when Th and U are present at levels of only a few ppm in host minerals.

关键词： Re-Os geochronology Arsenopyrite He-Ar isotopes Pingqiu Jinjing southeast Guizhou Province,China

Crustal Heat Production and Mantle Heat Flow in southeast China

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Science China Chemistry 1994年第10期37卷 1252-1263页

作者：胡圣标汪集旸 Institute of Geology Academia SinicaBeijing 100029PRC

The correlation between seismic velocity (v_p) and radiogenic heat production (A) en- ables the distribution of crustal heat production to be evaluated,from which the mantle heat flow for 21 seismic velocity-depth profiles located along the two continental geotraverses in southeast China can be *** approaches have been proposed to special problems connected with the conversion of seismic velocities into heat production in orogenic *** results show that the crustal heat flow in southeast China is quite inhomogeneous,varying between 17.8 and 46 mW·m^(-2),which can be attribut- ed to the complicated crustal structure related to overthrusting and overlapping in the upper *** re- markable regional variation in the mantle heat flow,ranging from 23.2 to 41.6 mW·m^(-2),corresponds to the large-scale tectonothermal evolution of the orogenic belts.

关键词： v_p-A conversion crustal heat production mantle heat flow southeast China

First record of contourites from Lower Devonian Lip-trap Formation in southeast Australia

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Science China Earth Sciences 2008年第7期51卷 939-946页

作者： G.R.SHI Key Laboratory of Biogeology and Environmental Geology of China Education Ministry Wuhan 430074 China Faculty of Earth Sciences China University of Geosciences Wuhan 430074 China

Typical contourite deposits associated with submarine turbidite fan deposits are recognized for the first time from the Lower Devonian Liptrap Formation at Cape Liatrap, Victoria in southeast Australia. The contourites are well integrated within the turbidite fan deposits and are characterized by thin (5-8 cm), lenticular, well-sorted coarse-grained siltstones to fine-grained sandstones with current-ripples and cross beddings. The palaeocurrent directions of the turbidite fan and contourites are perpendicular to each other, with the former directed generally westward while the latter varying from 165° to 190° southward. In view of the facies types and architecture, we suggest that the turbidite fan was developed at the base of a westward inclined palaeo-slope, at the front of which the contourites were deposited as a result of southward flowing deep-sea contour (geostrophic) currents. The depositional setting inter- preted for the Liptrap Formation thus may provide a provisional model for the Lower Devonian conti- nental slope and abyssal basin environment in the southeastern part of the Melbourne Trough.

关键词： Contourite turbidite Cape Liptrap Liptrap Formation southeast Australia

Observation of baroclinic eddies southeast of Okinawa Island

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Science China Earth Sciences 2008年第12期51卷 1802-1812页

作者： PARK Jae-Hun Graduate School of Oceanography University of Rhode Island

In the region southeast of Okinawa, during May to July 2001, a cyclonic and an anticyclonic eddy were observed from combined measurements of hydrocasts, an upward-looking moored acoustic Doppler current profiler (MADCP), pressure-recording inverted echo sounders (PIESs), satellite altimetry, and a coastal tide gauge. The hydrographic data showed that the lowest/highest temperature (T) and salinity (S) anomalies from a 13-year mean for the same season were respectively ?3.0/+2.5°C and ?0.20/+0.15 psu at 380/500 dbar for the cyclonic/anticyclonic eddies. From the PIES data, using a gravest empirical mode method, we estimated time-varying surface dynamic height (D) anomaly referred to 2000 dbar changing from ?20 to 30 cm, and time-varying T and S anomalies at 500 dbar ranging through about ±2 and°C ±0.2 psu, respectively. The passage of the eddies caused variations of both satellite-measured sea surface height anomaly (SSHA) and tide-gauge-measured sea level anomaly to change from about ?20 to 30 cm, consistent with the D anomaly from the PIESs. Bottom pressure sensors measured no variation related to these eddy activities, which indicated that the two eddies were dominated by baro-clinicity. Time series of SSHA map confirmed that the two eddies, originating from the North Pacific Subtropical Countercurrent region near 20°–30°N and 150°–160°E, traveled about 3000 km for about 18 months with mean westward propagation speed of about 6 cm/s, before arriving at the region southeast of Okinawa Island.

关键词： baroclinic eddy southeast of Okinawa Island PIES ADCP

Eocene magmatism(Maden Complex) in the southeast Anatolian Orogenic Belt: Magma genesis and tectonic implications

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Geoscience Frontiers 2018年第6期9卷 1829-1847页

作者： Mehmet Ali Erturk Melahat Beyarslan Sun-Lin Chung Te-Hsien Lin Firat University Department of Geological Engineering Institute of Earth Sciences Academia Sinica Department of Geosciences National Taiwan University

The origin and geodynamic setting of the Maden Complex, which is situated in the Bitlis-Zagros Suture Zone in the southeast Anatolian Orogenic Belt, is still controversial due to lack of systematic geological and geochemical data. Here we present new whole rock major-trace-rare earth element and Sre Nd isotope data from the Middle Eocene volcanic rocks exposed in Maden Complex and discuss their origin in the light of new and old data. The volcanic lithologies are represented mainly by basalt and andesite, and minor dacite that vary from low-K tholeiitic, calc-alkaline, high-K calc-alkaline, and shoshonitic in composition. They exhibit enrichments in large ion lithophile and light rare earth elements, with depletions in high field strength elements. Basaltic rocks have uniform Sr and Nd isotope ratios with high εNd(t) values varying from t5.5 to t6.7, in contrast to, andesitic rocks are characterized by low εNd(t) values ranging from à1.6 to à10. These geochemical and isotopic characteristics indicate that two end-members, a subduction-related mantle source and a continental crust, were involved in the magma genesis. Considering all geological and geochemical data, we suggest that the Eocene Maden magmatism occurred as a post-collisional product by asthenospheric upwelling owing to convective removal of the lithosphere during an extensional collapse of the southeast Anatolian ranges.

关键词： Maden Complex Eocene magmatism southeast Turkey Asthenospheric upwelling

Gravity pattern in southeast margin of Tibetan Plateau and its implications to tectonics and large earthquakes

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Earth and Planetary Physics 2019年第5期3卷 425-434页

作者： Yue Wu Yuan Gao Key Laboratory of Earthquake Prediction Institute of Earthquake ForecastingChina Earthquake Administration

There are many active faults in the southeast margin of Tibetan Plateau,where three large active faults zones,the Longmenshan,Xianshuihe and Anninghe,merge to form a"Y"*** crustal deformation and a complicated fault distribution accompany strong earthquake activity in this *** this paper,we investigate a multi-scale gravity anomaly in the southeastern margin of the Tibetan Plateau using the wavelet transform;we find that the pattern of the gravity field is closely related to the fault system in the study *** the characteristics of this Bouguer gravity anomaly at different orders indicates that the eastern Himalayan syntaxis has produced a strong eastward push during its northward movement,resulting in a shortening of the crust from west to east and a rapid uplift of the Tibetan *** Songpan–Garzêand Sichuan–Yunnan blocks have been forced to slip and extrude southward and eastward *** distributions of seven large earthquakes from 1970 to 2018 reflects the relationship between large earthquakes and characteristics of the gravity *** the tectonic backgrounds of several earthquakes reveals that the large earthquakes occur usually in the high gravity anomaly gradient zone,which corresponds in general to the boundary zones of the *** infer that large earthquakes occur primarily in high Bouguer gravity anomaly zones in the upper crust,while low Bouguer gravity anomalies encompass the lower crust and the uppermost mantle.

关键词： southeast margin of Tibetan Plateau Bouguer gravity anomaly(BA) wavelet transform(WT)and multiscale analysis(MA) focal mechanism of earthquake gradient zone

Remote sensing of land use/cover changes in South and southeast Asian Countries

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International Journal of Digital Earth 2019年第10期12卷 1099-1102页

作者： Krishna Vadrevu Andreas Heinimann Garik Gutman Chris Justice NASA Marshall Space Flight Center HuntsvilleAlabama Center for Development and Environment and Institute of Geography University of BernSwitzerland NASA Headquarters WashingtonUSA Department of Geographical Sciences University of Maryland College ParkUSA

Land-Use/Cover Changes(LU/CC)are occurring rapidly in South/southeast Asian(S/SEA)countries,generally associated with population growth,economic development and competing demands for *** the region,the most common LU/CC changes include urban expansion,agricultural land loss,land abandonment,deforestation,logging,reforestation,agricultural expansion,*** to South Asia,forest cover has been increasing in countries like India,Nepal,and Bhutan due to sustainable afforestation measures;whereas,large-scale deforestation in southeast Asian countries is continuing,for example,due to oil palm plantation expansion driven by the international market demand in Malaysia and ***-scale deforestation in most of the Southeast Asian countries is due to slash-and-burn agriculture by indigenous people,driven by poverty and population *** activities are common in Myanmar and *** terms of urbanization,South and southeast Asian countries contain 23 megacities,each with more than 10 million *** in these countries started as urban clusters which grow rapidly,merging into *** urbanization is driving agricultural land loss,and agricultural intensification has been increasing due to less availability of land for growing food crops as,for example,in India,Vietnam,and *** drivers of LU/CC vary widely in the region and include such factors as land tenure,local economic development,government policies,inappropriate land management,land speculation,improved road networks,***,variability in the weather,climate,and socioeconomic factors drive LU/CC resulting in disruptions of biogeochemical cycles,radiation and surface energy balance.

关键词： southeast crops logging

Anisakiasis in southeast Asia: A story of new tropical disease?

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Asian Pacific Journal of Tropical Biomedicine 2016年第5期6卷 382-383页

作者： Somsri Wiwanitkit Viroj Wiwanitkit Wiwanitkit House Bangkhae Hainan Medical University Faculty of Medicine University of Nis Joseph Ayobabalola University Dr DY Patil Medical University

Anisakiasis is an important worm infestation. It is seen in some non-tropical countries and becomes an important issue in coastal medicine. However, in the few recent years, there are some reports on occurrence of anisakiasis in tropical countries. In this specific short article,the authors review and present the situation of anisakiasis in southeast Asia. It can be said that anisakiasis becomes a new focused interest in tropical coastal medicine at present.

关键词： Anisakiasis southeast Asia Infestation Tropical disease