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| 1 | The dilemma of the Jiaodong gold deposits: Are they unique?显示文摘The ca. 126-120 Ma Au deposits of the Jiaodong Peninsula, eastern China, define the country's largest gold province with an overall endowment estimated as >3000 t Au. The vein and disseminated ores are hosted by NE- to NNE-trending brittle normal faults that parallel the margins of ca. 165-150 Ma, deeply emplaced, lower crustal melt granites. The deposits are sited along the faults for many tens of kilometers and the larger orebodies are associated with dilatational jogs. Country rocks to the granites are Precambrian high-grade metamorphic rocks located on both sides of a Triassic suture between the North and South China blocks. During early Mesozoic convergent deformation, the ore-hosting structures developed as ductile thrust faults that were subsequently reactivated during Early Cretaceous 'Yanshanian' intracontinental extensional deformation and associated gold formation.Classification of the gold deposits remains problematic. Many features resemble those typical of orogenic Au including the linear structural distribution of the deposits, mineralization style, ore and alteration assemblages, and ore fluid chemistry. However, Phanerozoic orogenic Au deposits are formed by prograde metamorphism of accreted oceanic rocks in Cordilleran-style orogens. The Jiaodong deposits, in contrast, formed within two Precambrian blocks approximately 2 billion years after devolatilization of the country rocks, and thus require a model that involves alternative fluid and metal sources for the ores. A widespread suite of ca. 130-123 Ma granodiorites overlaps temporally with the ores, but shows a poor spatial association with the deposits. Furthermore, the deposit distribution and mineralization style is atypical of ores formed from nearby magmas. The ore concentration requires fluid focusing during some type of sub-crustal thermal event, which could be broadly related to a combination of coeval lithospheric thinning, asthenospheric upwelling, paleo-Pacific plate subduction, and seismicity along the continental-scale Tan-Lu fault. Possible ore genesis scenarios include those where ore fluids were produced directly by the metamorphism of oceanic lithosphere and overlying sediment on the subducting paleo-Pacific slab, or by devolatilization of an enriched mantle wedge above the slab. Both the sulfur and gold could be sourced from either the oceanic sediments or the serpentinized mantle. A better understanding of the architecture of the paleo-Pacific slab during Early Cretaceous below the eastern margin of China is essential to determination of the validity of possible models. | Richard J.Goldfarb M.Santosh | 2014 | Geoscience Frontiers2014，5，2： | 102 |
| 2 | The giant Jiaodong gold province: The key to a unified model for orogenic gold deposits?显示文摘Although the term orogenic gold deposit has been widely accepted for all gold-only lode-gold deposits,with the exception of Carlin-type deposits and rare intrusion-related gold systems,there has been continuing debate on their genesis.Early syngenetic models and hydrothermal models dominated by meteoric fluids are now clearly unacceptable.Magmatic-hydrothermal models fail to explain the genesis of orogenic gold deposits because of the lack of consistent spatially- associated granitic intrusions and inconsistent temporal relationships.The most plausible,and widely accepted,models involve metamorphic fluids,but the source of these fluids is hotly debated.Sources within deeper segments of the supracrustal successions hosting the deposits,the underlying continental crust,and subducted oceanic lithosphere and its overlying sediment wedge all have their proponents.The orogenic gold deposits of the giant Jiaodong gold province of China,in the delaminated North China Craton,contain ca.120 Ma gold deposits in Precambrian crust that was metamorphosed over 2000 million years prior to gold mineralization.The only realistic source of fluid and gold is a subducted oceanic slab with its overlying sulfide-rich sedimentary package,or the associated mantle wedge.This could be viewed as an exception to a general metamorphic model where orogenic gold has been derived during greenschist- to amphibolite-facies metamorphism of supracrustal rocks:basaltic rocks in the Precambrian and sedimentary rocks in the Phanerozoic.Alternatively,if a holistic view is taken,Jiaodong can be considered the key orogenic gold province for a unified model in which gold is derived from late-orogenic metamorphic devolatilization of stalled subduction slabs and oceanic sediments throughout Earth history.The latter model satisfies all geological,geochronological,isotopic and geochemical constraints but the precise mechanisms of auriferous fluid release,like many other subduction-related processes,are model-driven and remain uncertain. | David I.Groves M.Santosh | 2016 | Geoscience Frontiers2016，7，3： | 29 |
| 3 | 内蒙古土贵乌拉孔兹岩带超高温变质作用:变质反应结构及P-T指示显示文摘内蒙古土贵乌拉地区分布了含石榴石花岗岩、夕线石榴黑云片麻岩以及二者以不同比例互层状组成的岩石,超高温变质岩以暗色含尖晶石堇青石夕线石榴黑云片麻岩条带或透镜体产于石榴石花岗岩和夕线石榴片麻岩中。基于[K]FMAS[H]系统以及岩石成因格子,认为超高温变质岩经历了三个阶段的变质:早期变质作用阶段,以同一石榴石颗粒中含有夕线石、尖晶石、石英等单相矿物包体为特征,表明变质作用进入到尖晶石+石英组合稳定域;峰期变质作用阶段,以尖晶石+石英、假蓝宝石+石英、斜方辉石+夕线石+石英三种超高温矿物组合为特征,表明峰期变质条件稳定在这三种矿物组合稳定域,指示变质温度高于1000℃;退变质阶段过程中,粗颗粒斜方辉石边部和核部 Al 含量的重新平衡,指示温度降低到950~970℃左右,表明了近等压冷却的退变质作用,随后由于快速抬升,发生了近等温降压的退变质作用,这个过程以各种反应边和后成合晶结构为标志,例如尖晶石与石英、假蓝宝石与石英之间有堇青石的反应边,石榴石外围有堇青石和斜方辉石的后成合晶。最后黑云母和斜方辉石分解为黑云母标志着高级变质作用的结束。内蒙古土贵乌拉地区超高温变质岩经历了逆时针的 P-T 演化特点。 | 刘守偈 李江海 M.Santosh | 2008 | 岩石学报2008，24，6： | 22 |
| 4 | Zircon U-Pb geochronology,geochemistry and Sr-Nd-Pb isotopes from the metamorphic basement in the Wuhe Complex:Implications for Neoarchean active continental margin along the southeastern North China Craton and constraints on the petrogenesis of Mesozoic g显示文摘我们在北方中国 Craton (NCC ) 的东南的边缘从 mafic granulites 和 Wuhe 建筑群的石榴石角闪岩报导锆石 U-Pb 地球年代学,地球化学和 Sr-Nd-Pb 同位素数据。在有以前的数据的联合,我们的结果证明这些岩石代表古老的更低的外壳的碎片,并且在 NCC 的北边缘有 granulite 地下室的类似于那些的特征。Pb 同位素数据的详细评估证明 Pb 同位素不能有效地关于岩浆的来源和产生把 Yangtze Craton 地下室的角色与 NCC 地下室的区分开来,至少为东南的 NCC。年龄数据建议在 Wuhe 建筑群的 granulites 或角闪岩的 protoliths 很可能在 Neoarchean 被产生并且这些岩石受到 Paleoproterozoic (1.81.9 Ga ) 高压的 granulite 外形变态。这研究也证明在力量在一个构造背景形成了的 NCC 的东南的边缘的前寒武纪的变形地下室由迟了的 Neoarchean 活跃大陆人边缘描绘了。 | Andong Wang Yican Liu M.Santosh Xiaofeng Gu | 2013 | Geoscience Frontiers2013，4，1： | 20 |
| 5 | Structural geometry of orogenic gold deposits: Implications for exploration of world-class and giant deposits显示文摘With very few exceptions, orogenic gold deposits formed in subduction-related tectonic settings in accretionary to collisional orogenic belts from Archean to Tertiary times. Their genesis, including metal and fluid source, fluid pathways, depositional mechanisms, and timing relative to regional structural and metamorphic events, continues to be controversial. However, there is now general agreement that these deposits formed from metamorphic fluids, either from metamorphism of intra-basinal rock sequences or de-volatilization of a subducted sediment wedge, during a change from a compressional to transpressional, less commonly transtensional, stress regime, prior to orogenic collapse. In the case of Archean and Paleoproterozoic deposits, the formation of orogenic gold deposits was one of the last events prior to cratonization. The late timing of orogenic gold deposits within the structural evolution of the host orogen implies that any earlier structures may be mineralized and that the current structural geometry of the gold deposits is equivalent to that at the time of their formation provided that there has been no significant post-gold orogenic overprint. Within the host volcano-sedimentary sequences at the province scale, world-class orogenic gold deposits are most commonly located in second-order structures adjacent to crustal scale faults and shear zones, representing the first-order ore-forming fluid pathways, and whose deep lithospheric connection is marked by lamprophyre intrusions which, however, have no direct genetic association with gold deposition. More specifically, the gold deposits are located adjacent to ~10°-25° district-scale jogs in these crustal-scale faults. These jogs are commonly the site of arrays of ~70° cross faults that accommodate the bending of the more rigid components, for example volcanic rocks and intrusive sills, of the host belts. Rotation of blocks between these accommodation faults causes failure of more competent units and/or reactivation and dilation of pre-existing structures, leading to deposit-scale focussing of ore-fluid and gold deposition.Anticlinal or antiformal fold hinges, particularly those of 'locked-up' folds with ~30° apical angles and overturned back limbs, represent sites of brittle-ductile rock failure and provide one of the more robust parameters for location of orogenic gold deposits.In orogenic belts with abundant pre-gold granitic intrusions, particularly Precambrian granitegreenstone terranes, the boundaries between the rigid granitic bodies and more ductile greenstone sequences are commonly sites of heterogeneous stress and inhomogeneous strain. Thus, contacts between granitic intrusions and volcano-sedimentary sequences are common sites of ore-fluid infiltration and gold deposition. For orogenic gold deposits at deeper crustal levels, ore-forming fluids are commonly focused along strain gradients between more compressional zones where volcano-sedimentary sequences are thinned and relatively more extensional zones where they are thickened. World-class orogenic gold deposits are commonly located in the deformed volcano-sedimentary sequences in such strain gradients adjacent to triple-point junctions defined by the granitic intrusions, or along the zones of assembly of micro-blocks on a regional scale. These repetitive province to district-scale geometrical patterns of structures within the orogenic belts are clearly critical parameters in geology-based exploration targeting for orogenic gold deposits. | David I.Groves M.Santosh Richard J.Goldfarb Liang Zhang | 2018 | Geoscience Frontiers2018，9，4： | 20 |
| 6 | 胶东金成矿系统的末端效应显示文摘胶东是中国最大的金矿集中区,金成矿作用具有瞬时性,是在同一成矿构造背景和同一流体成矿系统下完成的.胶东金矿床中控制金沉淀的两个重要机制,硫化和流体不混溶作用,均消耗成矿流体中的硫.H_(2)S从主成矿流体中逃逸,总硫浓度降低,不仅可导致金的高效沉淀,还能引起还原性矿物磁黄铁矿和氧化性矿物磁铁矿等矿物的沉淀.脉石矿物石英的溶解度受温度、压力和CO_(2)含量的影响,在低温时受压力影响小、在高温时受压力影响大,在低压时受温度影响小、在高压时受温度影响大.可以根据建立的石英溶解度模型,解释成矿脉体中石英溶解-再沉淀行为和不同类型石英脉的形成机制.也正是多期成矿流体活动,造成胶东金矿脉石英具有复杂的环带或溶蚀结构.胶东金矿主成矿期内的黄铁矿在单颗粒尺度显示出复杂的显微结构特征,微量元素(主要为富As环带与金的耦合)和硫同位素组成同样有一定规律性变化.富As流体可能是由于初始成矿流体流经富As的变沉积岩地层所导致,黄铁矿边部As-Au振荡环带的产生则与断层活动导致的压力波动和流体发生局部相分离有关.胶东金矿床中存在金成色的时空演化,水/岩反应(硫化作用)是早期金矿化的成矿机制,形成相对高成色金,而后期在浅部显著降压及伴随的流体相分离是晚期金矿化的成矿机制,形成低成色金.克拉通破坏背景下,新生下地壳发生角闪岩相-麻粒岩相的变质脱水,形成富含Au和CO_(2)的成矿流体.流体沿深大断裂及其次生构造上升,形成大规模断裂控制的金矿床. | 范宏瑞 蓝廷广 李兴辉 M.SANTOSH 杨奎锋 胡芳芳 冯凯 胡换龙 彭红卫 张永文 | 2021 | 中国科学:地球科学2021，51，9： | 17 |
| 7 | Continental reconstruction and metallogeny of the Circum-Junggar areas and termination of the southern Central Asian Orogenic Belt显示文摘Continental reconstructions in Central Asia are represented by orogenesis along some large orogenic belts in the Altaid collage(Fig.1)or Central Asian Orogenic Belt(CAOB),which separate the East European and Siberian cratons to the north from the Tarim and North China cratons to the south(Sengor et al.,1993;Jahn et al.,2004;Windley et al.,2007;Qu et al.,2008; | Wenjiao Xiao Min Sun M.Santosh | 2015 | Geoscience Frontiers2015，6，2： | 16 |
| 8 | Arsenic contamination of groundwater:A global synopsis with focus on the Indian Peninsula显示文摘More than 2.5 billion people on the globe rely on groundwater for drinking and providing high-quality drinking water has become one of the major challenges of human society.Although groundwater is considered as safe,high concentrations of heavy metals like arsenic(As)can pose potential human health concerns and hazards.In this paper,we present an overview of the current scenario of arsenic contamination of groundwater in various countries across the globe with an emphasis on the Indian Peninsula.With several newly affected regions reported during the last decade,a significant increase has been observed in the global scenario of arsenic contamination.It is estimated that nearly 108 countries are affected by arsenic contamination in groundwater with concentration beyond maximum permissible limit of 10 ppb recommended by the World Health Organization.The highest among these are from Asia(32)and Europe(31),followed by regions like Africa(20),North America(11),South America(9)and Australia(4).More than 230 million people worldwide,which include 180 million from Asia,are at risk of arsenic poisoning.Southeast Asian countries,Bangladesh,India,Pakistan,China,Nepal,Vietnam,Burma,Thailand and Cambodia,are the most affected.In India,20 states and 4 Union Territories have so far been affected by arsenic contamination in groundwater.An attempt to evaluate the correlation between arsenic poisoning and aquifer type shows that the groundwater extracted from unconsolidated sedimentary aquifers,particularly those which are located within the younger orogenic belts of the world,are the worst affected.More than 90%of arsenic pollution is inferred to be geogenic.We infer that alluvial sediments are the major source for arsenic contamination in groundwater and we postulate a strong relation with plate tectonic processes,mountain building,erosion and sedimentation.Prolonged consumption of arsenic-contaminated groundwater results in severe health issues like skin,lung,kidney and bladder cancer;coronary heart disease;bronchiectasis;hyperkeratosis and arsenicosis.Since the major source of arsenic in groundwater is of geogenic origin,the extend of pollution is complexly linked with aquifer geometry and aquifer properties of a region.Therefore,remedial measures are to be designed based on the source mineral,climatological and hydrogeological scenario of the affected region.The corrective measures available include removing arsenic from groundwater using filters,exploring deeper or alternative aquifers,treatment of the aquifer itself,dilution method by artificial recharge to groundwater,conjunctive use,and installation of nano-filter,among other procedures.The vast majority of people affected by arsenic contamination in the Asian countries are the poor who live in rural areas and are not aware of the arsenic poisoning and treatment protocols.Therefore,creating awareness and providing proper medical care to these people remain as a great challenge.Very few policy actions have been taken at international level over the past decade to reduce arsenic contamination in drinking water,with the goal of preventing toxic impacts on human health.We recommend that that United Nations Environment Programme(UNEP)and WHO should take stock of the global arsenic poisoning situation and launch a global drive to create awareness among people/medical professionals/health workers/administrators on this global concern. | E.Shaji M.Santosh K.V.Sarath Pranav Prakash V.Deepchand B.V.Divya | 2021 | Geoscience Frontiers2021，12，3： | 14 |
| 9 | Neoarchean granite-greenstone belts and related ore mineralization in the North China Craton:An overview显示文摘Tectonic processes involving amalgamations of microblocks along zones of ocean closure represented by granite-greenstone belts(GGB) were fundamental in building the Earth's early continents. The crustal growth and cratonization of the North China Craton(NCC) are correlated to the amalgamation of microblocks welded by 2.75-2.6 Ga and ~2.5 Ga GGBs. The lithological assemblages in the GGBs are broadly represented by volcano-sedimentary sequences, subduction-collision related granitoids and bimodal volcanic rocks(basalt and dacite) interlayered with minor komatiites and calc-alkalic volcanic rocks(basalt, andesite and felsic rock). The geochemical features of meta-basalts in the major GGBs of the NCC display affinity with N-MORB, E-MORB, OIB and calc-alkaline basalt, suggesting that the microblocks were separated by oceanic realm. The granitoid rocks display arc signature with enrichment of LILE(K,Rb, Sr, Ba) and LREE, and depletion of HFSE(Nb, Ta, Th, U, Ti) and HREE, and fall in the VAG field. The major mineralization includes Neoarchean BIF-type iron and VMS-type Cu-Zb deposits and these,together with the associated supracrustal rocks possibly formed in back-arc basins or arc-related oceanic slab subduction setting with or without input from mantle plumes. The 2.75-2.60 Ga TTG rocks,komatiites, meta-basalts and metasedimentary rocks in the Yanlingguan GGB are correlated to the upwelling mantle plume with eruption close to the continental margin within an ocean basin. The volcanosedimentary rocks and granitoid rocks in the late Neoarchean GGBs display formation ages of 2.60-2.48 Ga, followed by metamorphism at 2.52-2.47 Ga, corresponding to a typical modern-style subduction-collision system operating at the dawn of Proterozoic. The late Neoarchean komatiite(Dongwufenzi GGB), sanukitoid(Dongwufenzi GGB and Western Shandong GGB), BIF(Zunhua GGB) and VMS deposit(Hongtoushan-Qingyuan-Helong GGB) have closer connection to a combined process of oceanic slab subduction and mantle plume. The Neoarchean cratonization of the NCC appears to have involved two stages of tectonic process along the 2.75-2.6 Ga GGB and ~2.5 Ga GGBs, the former involve plume-arc interaction process, and the latter involving oceanic lithospheric subduction, with or without arcplume interaction. | Li Tang M.Santosh | 2018 | Geoscience Frontiers2018，9，3： | 11 |
| 10 | The conjunction of factors that lead to formation of giant gold provinces and deposits in non-arc settings显示文摘It is quite evident that it is not anomalous metal transport,nor unique depositional conditions,nor any single factor at the deposit scale,that dictates whether a mineral deposit becomes a giant or not.A hierarchical approach thus is required to progressively examine controlling parameters at successively decreasing scales in the total mineral system to understand the location of giant gold deposits in non-arc environments.For giant orogenic,intrusion-related gold systems(IRGS) and Carlin-type gold deposits and iron oxide-copper-gold(IOCG) deposits,there are common factors among all of these at the lithospheric to crustal scale.All are sited in giant gold provinces controlled by complex fundamental fault or shear zones that follow craton margins or,in the case of most Phanerozoic orogenic giants,define the primary suture zones between tectonic terranes.Giant provinces of IRGS,IOCG,and Carlin-type deposits require melting of metasomatized lithosphere beneath craton margins with ascent of hybrid lamprophyric to granitic magmas and associated heat flux to generate the giant province.The IRGS and IOCG deposits require direct exsolution of volatile-rich magmatic-hydrothermal fluids,whereas the association of such melts with Carlin-type ores is more indirect and enigmatic.Giant orogenic gold provinces show no direct relationship to such magmatism.forming from metamorphic fluids,but show an indirect relationship to lamprophyres that reflect the mantle connectivity of controlling first-order structures.In contrast to their province scale similarities,the different giant gold deposit styles show contrasting critical controls at the district to deposit scale.For orogenic gold deposits,the giants appear to have formed by conjunction of a greater number of parameters to those that control smaller deposits,with resultant geometrical and lithostratigraphic complexity as a guide to their location.There are few giant IRGS due to their inferior fluid-flux systems relative to orogenic gold deposits,and those few giants are essentially preservational exceptions.Many Carlin-type deposits are giants due to the exceptional conjunction of both structural and lithological parameters that caused reactive and permeable rocks,enriched in syngenetic gold,to be located below an impermeable cap along antiformal 'trends'.Hydrocarbons probably played an important role in concentrating metal.The supergiant Post-Betze deposit has additional ore zones in strain heterogeneities surrounding the pre-gold Goldstrike stock.All unequivocal IOCG deposits are giant or near-giant deposits in terms of gold-equivalent resources,partly due to economic factors for this relatively poorly understood,low Cu-Au grade deposit type.The supergiant Olympic Dam deposit,the most shallowly formed deposit among the larger IOCGs,probably owes its origin to eruption of volatile-rich hybrid magma at surface,with formation of a large maar and intense and widespread brecciation,alteration and Cu-Au-U deposition in a huge rock volume. | David I.Groves Richard J.Goldfarb M.Santosh | 2016 | Geoscience Frontiers2016，7，3： | 11 |
| 11 | Plate tectonic control on the formation and tectonic migration of Cenozoic basins in northern margin of the South China Sea显示文摘The tectonic evolution history of the South China Sea(SCS) is important for understanding the interaction between the Pacific Tectonic Domain and the Tethyan Tectonic Domain,as well as the regional tectonics and geodynamics during the multi-plate convergence in the Cenozoic.Several Cenozoic basins formed in the northern margin of the SCS,which preserve the sedimentary tectonic records of the opening of the SCS.Due to the spatial non-uniformity among different basins,a systematic study on the various basins in the northern margin of the SCS constituting the Northern Cenozoic Basin Group(NCBG) is essential.Here we present results from a detailed evaluation of the spatial-temporal migration of the boundary faults and primary unconformities to unravel the mechanism of formation of the NCBG.The NCBG is composed of the Beibu Gulf Basin(BBGB),Qiongdongnan Basin(QDNB),Pearl River Mouth Basin(PRMB) and Taixinan Basin(TXNB).Based on seismic profiles and gravity-magnetic anomalies,we confirm that the NE-striking onshore boundary faults propagated into the northern margin of the SCS.Combining the fault slip rate,fault combination and a comparison of the unconformities in different basins,we identify NE-striking rift composed of two-stage rifting events in the NCBG:an early-stage rifting(from the Paleocene to the Early Oligocene) and a late-stage rifting(from the Late Eocene to the beginning of the Miocene).Spatially only the late-stage faults occurs in the western part of the NCBG(the BBGB,the QDNB and the western PRMB),but the early-stage rifting is distributed in the whole NCBG.Temporally,the early-stage rifting can be subdivided into three phases which show an eastward migration,resulting in the same trend of the primary unconformities and peak faulting within the NCBG.The late-stage rifting is subdivided into two phases,which took place simultaneously in different basins.The first and second phase of the early-stage rifting is related to back-arc extension of the Pacific subduction retreat system.The third phase of the earlystage rifting resulted from the joint effect of slab-pull force due to southward subduction of the proto-SCS and the back-arc extension of the Pacific subduction retreat system.In addition,the first phase of the late-stage faulting corresponds with the combined effect of the post-collision extension along the Red River Fault and slab-pull force of the proto-SCS subduction.The second phase of the late-stage faulting fits well with the sinistral faulting of the Red River Fault in response to the Indochina Block escape tectonics and the slab-pull force of the proto-SCS. | Pengcheng Wang Sanzhong Li Yanhui Suo Lingli Guo Guangzeng Wang Gege Hui M.Santosh Ian D.Somerville Xianzhi Cao Yang Li | 2020 | Geoscience Frontiers2020，11，4： | 10 |
| 12 | Voyage of the Indian subcontinent since Pangea breakup and driving force of supercontinent cycles: Insights on dynamics from numerical modeling显示文摘Recent advances in three-dimensional numerical simulations of mantle convection have aided in approximately reproducing continental movement since the Pangea breakup at 200 Ma. These have also led to a better understanding of the thermal and mechanical coupling between mantle convection and surface plate motion and predictions of the configuration of the next supercontinent. The simulations of mantle convection from 200 Ma to the present reveals that the development of large-scale cold mantle downwellings in the North Tethys Ocean at the earlier stage of the Pangea breakup triggered the northward movement of the Indian subcontinent. The model of high temperature anomaly region beneath Pangea resulting from the thermal insulation effect support the breakup of Pangea in the real Earth time scale, as also suggested in previous geological and geodynamic models. However, considering the low radioactive heat generation rate of the depleted upper mantle, the high temperature anomaly region might have been generated by upwelling plumes with contribution of deep subducted TTG(tonalite-trondhjemite-granite) materials enriched in radiogenic elements. Integrating the numerical results of mantle convection from 200 Ma to the present, and from the present to the future, it is considered that the mantle drag force acting on the base of continents may be comparable to the slab pull force, which implies that convection in the shallower part of the mantle is strongly coupled with surface plate motion. | Masaki Yoshida M.Santosh | 2018 | Geoscience Frontiers2018，9，5： | 9 |
| 13 | The naked planet Earth:Most essential pre-requisite for the origin and evolution of life显示文摘我们的蓝行星地球长被考虑了带充满为自从行星的出生,招待生活的营养素。这里,我们推测导致了在地球上的早年生活和它的余殃的出生的过程,最后导致 metazoans 的进化。我们评估:(1 ) 营养素的来源,(2 ) 初发的海洋的化学,(3 ) 海洋的起始的团,并且(4 ) 行星的尺寸。在生活大楼营养素之中,磷和钾起一个关键作用。仅仅岩石的三种类型能担任营养素的足够的来源:(a) 形成大陆的 TTG (花岗石) ,启用原始生活的进化到 metazoans;(b) 有 KREEP (钾,稀土元素元素,和磷) 的初发的大陆带一种粒状火成岩暗岩,它是的关键忍受生活;(c) carbonatite 岩浆,在象 U 和 Th 那样的放射产生的元素充实,它能引起变化加快进化并且在大陆人裂缝背景支持新种类的出生。第二个重要因素是海洋化学。初发的海洋是极其酸的(pH = 12 ) 并且在卤素(Cl, F 和其它) 充实, S, N 和金属性的元素(Cd, Cu, Zn,和其它) ,禁止生活的出生。在防碍 RNA 的这些元素上面清洗的板 tectonics。蓝海洋最后与 pH = 出现在 Phanerozoic 7 通过和由捱过,侵蚀和交通进海洋的表面大陆人外壳的广泛的相互作用。起始的海洋团也是重要的。生活的出生和进化的余殃深在有 35 km 的适于居住的地区是可能的能供应足够的营养素的海洋。没有一个巨大的大陆,营养素不能仅仅由山脉热水的循环被供应进海洋在地府。最后,行星的尺寸起一个关键作用。巨大的行星冷却不比更小的有效,以便进披风的海水的回来流动不发生直到中央恒星完成他们的主要顺序。由于土的合适的尺寸, Phanerozoic 的黎明见证海水的回来流动的开始进披风,导致巨大的大陆在上面的出现海平面,并且全球规模上的营养素的分发。氧泵也起了一个关键作用从那以后把 high-PO2 放在空气,导致入侵陆地的臭氧层和创新动物和植物的出现。满足紧密的条件使地球适于居住,初发的土的形成机制是一个重要因素。起初,一个干燥地球必须通过巨大的影响被做,由岩浆海洋列在后面漂浮充实营养素的初发的大陆(一种粒状火成岩 + KREEP ) 。从星状的带的迟了的轰炸供应了水使 35 km 成为厚海洋,并且在凉爽的木星以外不从从 Kuiper 的冰冷的陨星系上带子。满足与发展生活形式作为一个适于居住的行星启用了地球的上述条件是必要的。我们为在地球上的生活的出生和进化评估的紧密的限制将为寻找在 exo 太阳的行星的生活的行星的科学家提供重要指南。 | S.Maruyama M.Ikoma H.Genda K.Hirose T.Yokoyama M.Santosh | 2013 | Geoscience Frontiers2013，4，2： | 9 |
| 14 | Initiation of plate tectonics in the Hadean: Eclogitization triggered by the ABEL Bombardment显示文摘When plate tectonics began on the Earth has been long debated and here we argue this topic based on the records of Earth-Moon geology and asteroid belt to conclude that the onset of plate tectonics was during the middle Hadean(4.37-4.20 Ga). The trigger of the initiation of plate tectonics is the ABEL Bombardment, which delivered oceanic and atmospheric components on a completely dry reductive Earth, originally comprised of enstatite chondrite-like materials. Through the accretion of volatiles, shock metamorphism processed with vaporization of both CI chondrite and supracrustal rocks at the bombarded location, and significant recrystallization went through under wet conditions, caused considerable eclogitization in the primordial continents composed of felsic upper crust of 21 km thick anorthosite, and 50 km or even thicker KREEP lower crust. Eclogitization must have yielded a powerful slab-pull force to initiate plate tectonics in the middle Hadean. Another important factor is the size of the bombardment. By creating Pacific Ocean class crater by 1000 km across impactor, rigid plate operating stagnant lid tectonics since the early Hadean was severely destroyed, and oceanic lithosphere was generated to have bi-modal lithosphere on the Earth to enable the operation of plate tectonics.Considering the importance of the ABEL Bombardment event which initiated plate tectonics including the appearance of ocean and atmosphere, we propose that the Hadean Eon can be subdivided into three periods:(1) early Hadean(4.57-4.37 Ga),(2) middle Hadean(4.37-4.20 Ga), and(3) late Hadean(4.20-4.00 Ga). | Shigenori Maruyama M.Santosh Shintaro Azuma | 2018 | Geoscience Frontiers2018，9，4： | 8 |
| 15 | Prograde and retrograde growth of monazite in migmatites:An example from the Nagercoil Block,southern India显示文摘Data from a migmatised metapelite raft enclosed within charnockite provide quantitative constraints on the pressure-temperature-time[P-T-t) evolution of the Nagercoil Block at the southernmost tip of peninsular India.An inferred peak metamorphic assemblage of garnet,K-feldspar.sillimanite,plagioclase,magnetite,ilmenite,spinel and melt is consistent with peak metamorphic pressures of 6-8 kbar and temperatures in excess of 900℃.Subsequent growth of cordierite and biotite record high-temperature retrograde decompression to around 5 kbar and 800 C.SHRIMP U-Pb dating of magmatic zircon cores suggests that the sedimentary protoliths were in part derived from felsic igneous rocks with Palaeoproterozoic crystallisation ages.New growth of metamorphic zircon on the rims of detrital grains constrains the onset of melt crystallisation,and the minimum age of the metamorphic peak,to around560 Ma.The data suggest two stages of monazite growth.The first generation of REE-enriched monazite grew during partial melting along the prograde path at around 570 Ma via the incongruent breakdown of apatite.Relatively REE-depleted rims,which have a pronounced negative europium anomaly,grew during melt crystallisation along the retrograde path at around 535 Ma.Our data show the rocks remained at suprasolidus temperatures for at least 35 million years and probably much longer,supporting a long-lived high-grade metamorphic history.The metamorphic conditions,timing and duration of the implied clockwise P-T-t path are similar to that previously established for other regions in peninsular India during the Ediacaran to Cambrian assembly of that part of the Gondwanan supercontinent. | Tim E.Johnson Chris Clark Richard J.M.Taylor M.Santosh Alan S.Collins | 2015 | Geoscience Frontiers2015，6，3： | 8 |
| 16 | Province-scale commonalities of some world-class gold deposits:Implications for mineral exploration显示文摘Discovery rates for all metals,including gold,are declining,the cost per significant discovery is increasing sharply,and the economic situation of the industry is one of low base rate.The current hierarchical structure of the exploration and mining industry makes this situation difficult to redress.Economic geologists can do little to influence the required changes to the overall structure and philosophy of an industry driven by business rather than geological principles.However,it should be possible to follow the lead of the oil industry and improve the success rate of greenfield exploration,necessary for the next group of lower-exploration-spend significant mineral deposit discoveries.Here we promote the concept that mineral explorers need to carefully consider the scale at which their exploration targets are viewed.It is necessary to carefully assess the potential of drill targets in terms of terrane to province to district scale,rather than deposit scale,where most current economic geology research and conceptual thinking is concentrated.If otogenic,IRGD,Carlin-style and 10 CG gold-rich systems are viewed at the deposit scale,they appear quite different in terms of conventionally adopted research parameters.However,recent models for these deposit styles show increasingly similar source-region parameters when viewed at the lithosphere scale,suggesting common tectonic settings.It is only by assessing individual targets in their tectonic context that they can be more reliably ranked in terms of potential to provide a significant drill discovery.Targets adjacent to craton margins,other lithosphere boundaries,and suture zones are clearly favoured for all of these gold deposit styles,and such exploration could lead to incidental discovery of major deposits of other metals sited along the same tectonic boundaries. | David I.Groves M.Santosh | 2015 | Geoscience Frontiers2015，6，3： | 8 |
| 17 | Ancient deep roots for Mesozoic world-class gold deposits in the north China craton:An integrated genetic perspective显示文摘The North China Craton(NCC)hosts some of the world-class gold deposits that formed more than 2 billion years after the major orogenic cycles and cratonization.The diverse models for the genesis of these deposits remain equivocal,and mostly focused on the craton margin examples,although synchronous deposits formed in the interior domains.Here we adopt an integrated geological and geophysical perspective to evaluate the possible factors that contributed to the formation of the major gold deposits in the NCC.In the Archean tectonic framework of the NCC,the locations of the major gold deposits fall within or adjacent to greenstone belts or the margins of micro-continents.In the Paleoproterozoic framework,they are markedly aligned along two major collisional sutures-the Trans North China Orogen and the Jiao-Liao-Ji Belt.Since the Mesozoic intrusions hosting these deposits do not carry adequate signals for the source of gold,we explore the deep roots based on available geophysical data.We show that the gold deposits are preferentially distributed above zones of uplifted MOHO and shallow LAB corresponding to thinned crust and eroded sub-lithospheric mantle,and that the mineralization is located above regions of high heat flow representing mantle upwelling.The NCC was at the center of a multi-convergent regime during the Mesozoic which intensely churned the mantle and significantly en riched it.The geophysical data on Moho and LAB upwarp from the centre towards east of the craton is more consistent with paleo-Pacific slab subduction from the east exerting the dominant control on lithospheric thinning.Based on these results,and together with an evaluation of the geochemical and isotopic features of the Mesozoic magmatic intrusions hosting the gold mineralization,we propose a genetic model that invokes reworking of ancient Au archives preserved in the lower crust and metasomatised upper mantle and which were generated through multiple subduction,underplating and cumulation events associated with cratonization of the NCC as well as the subduction-collision of Yangtze Craton with the NCC.The heat and material input along zones of heterogeneously thinned lithosphere from a rising turbulent mantle triggered by Mesozoic convergent margins surrounding the craton aided in reworking the deep roots of the ancient Au reservoirs,leading to the major gold metallogeny along craton margins as well as in the interior of the NCC. | Cheng-Xue Yang M.Santosh | 2020 | Geoscience Frontiers2020，11，1： | 8 |
| 18 | Sapphirine granulites from Panasapattu,Eastern Ghats belt,India:Ultrahigh-temperature metamorphism in a Proterozoic convergent plate margin显示文摘我们报导平衡在从在在东方 Ghats granulite 的 Paderu 区域的 Panasapattu 的一个新地区的 biotiteorthopyroxenegarnet granulites 的蓝宝石的 + 石英集合系上带子,哪个提供新证据为超离频温度(UHT ) 在 10301050 汵瑩獥 ? 的变态 ??? 桇瑡吗?? | C.V.Dharma Rao M.Santosh Reia M.Chmielowski | 2012 | Geoscience Frontiers2012，3，1： | 7 |
| 19 | Arc magmatism as a window to plate kinematics and subduction polarity:Example from the eastern Pontides belt,NE Turkey显示文摘在土耳其的黑海区域的东方 Pontides orogenic 带在 Paleotethys 的闭合期间把一扇批评窗户提供给板 kinematics 和 subduction 极性。这里,我们从这条带在最近的信息上提供简短合成。我们在迟了的白垩纪和新生代弧 magmatism 基于清楚的空间、时间的变化为东方 Pontides orogenic 带和它的联系迟了的 MesozoicCenozoic magmatism 的起源推断向南方的 subduction,和沿着黑海的全部南部的海岸的一个突出的蘸南方的反向的差错系统的存在。我们的模型与赞成的一些最近的建议不符一向北方 subduction 极性,并且在评估与会聚的边缘过程联系的 geodynamic 周围说明弧 magmatism 的重要性。 | Yener Eyuboglu M.Santosh Osman Bektas Seda Ayhan | 2011 | Geoscience Frontiers2011，2，1： | 6 |
| 20 | Detrital zircon geochronology of the Lutzow-Holm Complex,East Antarctica:Implications for Antarctica-Sri Lanka correlation显示文摘The Lützow-Holm Complex(LHC) of East Antarctica has been regarded as a collage of Neoarchean(ca.2.5 Ga), Paleoproterozoic(ca. 1.8 Ga), and Neoproterozoic(ca. 1.0 Ga) magmatic arcs which were amalgamated through the latest Neoproterozoic collisional events during the assembly of Gondwana supercontinent. Here, we report new geochronological data on detrital zircons in metasediments associated with the magmatic rocks from the LHC, and compare the age spectra with those in the adjacent terranes for evaluating the tectonic correlation of East Antarctica and Sri Lanka. Cores of detrital zircon grains with high Th/U ratio in eight metasediment samples can be subdivided into two dominant groups:(1) late Meso-to Neoproterozoic(1.1-0.63 Ga) zircons from the northeastern part of the LHC in Prince Olav Coast and northern Soya Coast areas, and(2) dominantly Neoarchean to Paleoproterozoic(2.8-2.4 Ga) zircons from the southwestern part of the LHC in southern Lutzow-Holm Bay area. The ca.1.0 Ga and ca. 2.5 Ga magmatic suites in the LHC could be proximal provenances of the detrital zircons in the northeastern and southwestern LHC, respectively. Subordinate middle to late Mesoproterozoic(1.3-1.2 Ga) detrital zircons obtained from Akarui Point and Langhovde could have been derived from adjacent Gondwana fragments(e.g., Rayner Complex, Eastern Ghats Belt). Meso-to Neoproterozoic domains such as Vijayan and Wanni Complexes of Sri Lanka, the southern Madurai Block of southern India, and the central-western Madagascar could be alternative distal sources of the late Meso-to Neoproterozoic zircons. Paleo-to Mesoarchean domains in India, Africa, and Antarctica might also be distal sources for the minor ~2.8 Ga detrital zircons from Skallevikshalsen. The detrital zircons from the Highland Complex of Sri Lanka show similar Neoarchean to Paleoproterozoic(ca. 2.5 Ga) and Neoproterozoic(ca. 1.0 Ga) ages, which are comparable with those of the LHC, suggesting that the two complexes might have formed under similar tectonic regimes. We consider that the Highland Complex and metasedimentary unit of the LHC formed a unified latest Neoproterozoic suture zone with a large block of northern LH-Vijayan Complex caught up as remnant of the ca. 1.0 Ga magmatic arc. | Yusuke Takamura Toshiaki Tsunogae M.Santosh Yukiyasu Tsutsumi | 2018 | Geoscience Frontiers2018，9，2： | 6 |
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