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菲律宾出露有20余套规模各异的俯冲带上板块(SSZ)型蛇绿岩,它们的时代以晚中生代为主,仅少数为新生代。大多数菲律宾蛇绿岩出露相对完整,包括由二辉橄榄岩、方辉橄榄岩、纯橄岩等组成的变质地幔岩,和堆晶辉石岩、辉长辉绿岩等深成岩,以及枕状玄武岩、熔岩等喷出岩,甚至燧石岩等上覆沉积物,部分发育席状岩墙群和与蛇绿岩相关的构造混杂岩及变质基底。其中喷出岩在地球化学特征上整体表现出类似MORB和IAT的REE配分模式,具LILE富集和HFSE (如Nb、Ta相对La、Th)弱到中等程度亏损的特征。通过对菲律宾蛇绿岩的形成年代、岩石组合、地球化学特征及构造环境的分析,并与东南亚地区其他同时代蛇绿岩和周缘边缘海进行对比,将菲律宾蛇绿岩分为两部分。(1)菲律宾活动带蛇绿岩,该蛇绿岩带自西向东出露晚中生代弧前、新生代弧前扩张盆地和晚中生代岛弧、弧后盆地的残留,推测晚中生代蛇绿岩来自中特提斯洋向古太平洋板块俯冲所形成的沟-弧-盆体系,是菲律宾新生代岛弧岩浆活动的基底,而夹于晚中生代蛇绿岩之间的始新世蛇绿岩来自老的岛弧基底之上由于新特提斯洋俯冲形成的弧前扩张盆地。(2)菲律宾陆块蛇绿岩,其中巴拉望微陆块晚中生代蛇绿岩来源于古南海,而构造叠置于它们之上的新生代蛇绿岩则来源于古南海俯冲对应形成的边缘海,如苏禄海和南海;三宝颜微陆块或可能是古南海的南部被动大陆边缘,其蛇绿岩可能是古南海的残片,抑或三宝颜微陆块可能是婆罗洲南部东爪哇-西苏拉威西地体的延续,故该蛇绿岩又可能是新特提斯洋的残片。

大地构造图反映着作者对大地构造演化过程和动力机制的理解,往往以某种大地构造观点为指导。经历了20世纪七八十年代百家争鸣的大地构造编图时代以后,随着板块构造理论的引进,各家观点在承认板块构造理论的同时,表述各有侧重。地质地球物理调查是大地构造编图的资料基础,近年来,调查资料无论在数量上还是在精度上,都有较大的突破。但是,海区的大地构造编图还存在一些问题,就是海区调查研究基础与陆区相比还相对薄弱,近十年来海区的地调科研成果也没有表现在大区域的,尤其是涵盖全海区或整个中国海陆的大地构造图上。多种地球物理资料的综合研究,可以作为中国海陆大地构造对比和研究的纽带,地质、地球物理和地球化学方法和资料的综合应用,可作为大地构造编图的重要基础。从一个海洋地质构造工作者的角度,在阐释对我国大地构造编图的历史、观点、资料、成果及努力方向理解的基础上,希望通过正在执行的\"中国海陆大地构造格架图\",为编制中国大地构造图的思路做一个新探索。

Based on the drilling data, the geological characteristics of the coast in South China, and the interpretation of the long seismic profiles covering the Pearl River Mouth Basin and southeastern Hainan Basin, the basin basement in the northern South China Sea is divided into four structural layers, namely, Pre-Sinian crystalline basement, Sinian-lower Paleozoic, upper Paleozoic, and Mesozoic structural layers. This paper discusses the distribution range and law and reveals the tectonic attribute of each structural layer. The Pre-Sinian crystalline basement is distributed in the northern South China Sea, which is linked to the Pre-Sinian crystalline basement of the Cathaysian Block and together they constitute a larger-scale continental block—the Cathaysian-northern South China Sea continental block. The Sinian-lower Paleozoic structural layer is distributed in the northern South China Sea, which is the natural extension of the Caledonian fold belt in South China to the sea area. The sediments are derived from southern East China Sea-Taiwan, Zhongsha-Xisha islands and Yunkai ancient uplifts, and some small basement uplifts. The Caledonian fold belt in the northern South China Sea is linked with that in South China and they constitute the wider fold belt. The upper Paleozoic structural layer is unevenly distributed in the northern South China. In the basement of Beibu Gulf Basin and southwestern Taiwan Basin, the structural layer is composed of the stable epicontinental sea deposit. The distribution areas in the Pearl River Mouth Basin and the southeastern Hainan Basin belong to ancient uplifts in the late Paleozoic, lacking the upper Paleozoic structural layers. The stratigraphic distribution and sedimentary environment in Middle-Late Jurassic to Cretaceous are characteristic of differentiation in the east and the west. The marine, paralic deposit is well developed in the basin basement of southwestern Taiwan but the volcanic activity is not obvious. The marine and paralic facies deposit is distributed in the eastern Pearl River Mouth Basin basement and the volcanic activity is stronger. The continental facies volcano-sediment in the Early Cretaceous is distributed in the basement of the western Pearl River Mouth Basin and Southeastern Hainan Basin. The Upper Cretaceous red continental facies clastic rocks are distributed in the Beibu Gulf Basin and Yinggehai Basin. The NE direction granitic volcanic-intrusive complex, volcano-sedimentary basin, fold and fault in Mesozoic basement have the similar temporal and spatial distribution, geological feature, and tectonic attribute with the coastal land in South China, and they belong to the same magma-deposition-tectonic system, which demonstrates that the late Mesozoic structural layer was formed in the background of active continental margin. Based on the analysis of basement structure and the study on tectonic attribute, the paleogeographic map of the basin basement in different periods in the northern South China Sea is compiled.

The Neogene sediments of Gansu Group from northwestern China contain eolian and fluvial deposits. The origins of these sediments are very important for exploring the onset of Asian inland aridification, the pattern of paleo-atmospheric circulation, and the regional tectonics and geomorphic evolution during the Miocene. Here we present detrital-zircon age spectra of typical eolian and fluvial deposits from highlands and subsidence basin, and compare them with those of surrounding eroded mountain（such as the West Qinling Mountains and Liupan Mountains） materials and Quaternary loess derived from the Asian inlands. The results reveal that（1） the detrital-zircon age spectrum of the Miocene eolian sample is remarkably different from the eroded materials of the West Qinling Mountains and the Miocene fluvial deposits from Tianshui region, but very similar to the Quaternary loess deposits. This indicates that the provenance of Miocene eolian sediments is similar with the Quaternary loess, and thus further confirms the previous conclusions that the distribution of Asian arid lands and the pattern of atmospheric circulation during the Miocene are broadly similar with the Quaternary.（2） The detrital-zircon age spectrum of the fluvial deposits（with age about 11.5 Ma） from Tianshui region is different from the eroded materials of West Qinling Mountains, but similar with that of the Liupan Mountains to the east, which may suggest that the Liupan Mountains have already been exhumed by 11.5 Ma.

The nearly EW-trending East Kunlun fault zone is the north boundary of the Bayan Har block.The activity characteristics and the position of the eastern end of its eastward extension are of great significance to probing into the dynamic mechanism of formation of the east edge of the Tibetan Plateau,and also lay the foundation for seismic risk assessment of the fault zone.The following results are obtained by analysis based on satellite image interpretation of landforms,surface rupture survey,terrace scarp deformation survey,and terrace dating data on the eastern part of the East Kunlun fault zone：（1）the Luocha segment is a Holocene active fault,where a reverse L-shape paleoearthquake surface rupture zone of about 50 km long is located;（2）the Luocha segment is characterized by left-lateral slip movement under the compression-shear condition since the later period of the Late Pleistocene,with a rate of 7.68–9.37 mm/a and a vertical slip rate of 0.7–0.9 mm/a,which are basically in accord with the activity rate of segments on its west side.The results indicate that it is a part of eastward extension of the East Kunlun fault zone;（3）the high-speed linear horizontal slip of the nearly EW-trending East Kunlun fault zone is blocked by the South China block at east,and transforms into the vertical movement of the nearly SN-NNE trending Minjiang fault zone and the Longmenshan fault zone,and the uplift of Longmenshan and Minjiang.The area where transform of the two tectonic systems occurred confines the position of the east end;（4）Luocha segment and Maqu segment constitute the＂Maqu seismic gap＂,so,seismic risk at Maqu segment is higher than that at Luocha segment,which should attract more attention.

In this paper, two sets of gravity and magnetic data were used to study the tectonics of the southern East China Sea and Ryukyu trench-arc system： one data set was from the ＇Geological-geophysical map series of China Seas and adjacent areas＇ database and the other was newly collected by R/VKexue Ⅲ in 2011. Magnetic and gravity data were reorganized and processed using the software MMDP, MGDP and RGIS. In addition to the description of the anomaly patterns in different areas, deep and shallow structure studies were performed by using several kinds of calculation, including a spectrum analysis, upward-continuation of the Bouguer anomaly and horizontal derivatives of the total-field magnetic anomaly. The depth of the Moho and magnetic basement were calculated. Based on the above work, several controversial tectonic problems were discussed. Compared to the shelf area and Ryukyu Arc, the Okinawa Trough has an obviously thinned crust, with the thinnest area having thickness less than 14km in the southern part. The Taiwan-Sinzi belt, which terminates to the south by the NW-SE trending Miyako fault belt, contains the relic volcanic arc formed by the splitting of the paleo Ryukyu volcanic arc as a result of the opening of the Okinawa Trough. As an important tectonic boundary, the strike-slip type Miyako fault belt extends northwestward into the shelf area and consists of several discontinuous segments. A forearc terrace composed of an exotic terrane collided with the Ryukyu Arc following the subduction of the Philippine Sea Plate. Mesozoic strata of varying thicknesses exist beneath the Cenozoic strata in the shelf basin and significantly influence the magnetic pattern of this area. The gravity and magnetic data support the existence of a Great East China Sea, which suggests that the entire southern East China Sea shelf area was a basin in the Mesozoic without alternatively arranged uplifts and depressions, and might have extended southwestward and connected with the northern South China Sea shelf basin.

Shahre-Babak ophiolite is a part of the inner Zagros ophiolite belt in Iran. Major parts of intrusive masses of Share-Babak ophiolite are gabbro and plagiogranite. The SiO2 versus Na2O＋K2O diagram shows that the palgiogranites are related to calk-alkaline series. Rare earth elements exhibit relatively similar pattern that indicates these rocks are syngenetic. Also, REE patterns display an enrichment of LREE compared to HREE, and are characterized by flat to slightly concaveup patterns from Gd to Yb. Such patterns contrast sharply with those of plagiogranites in more complete ophiolite sequences, such as the Semail ophiolite, Oman, or the Troodos ophiolite, Cyprus, and Neyriz, where patterns are much flatter and slightly LREE-depleted. The slightly LREE-enriched patterns of the Shahre-Babak plagiogranites support a partial melting origin for them. The low TiO2, Nb, Ta content and high LREE concentrations of the Shahre-Babak plagiogranites indicate that the rocks were likely derived from the anatexis of amphibolites, which were related to hydrothermal alteration of gabbros in intra-oceanic back-arc basin.

Granulite xenoliths are found in the early Mesozoic diorite intrusions from Chifeng and Ningcheng areas, eastern Inner Mon- golia. The granulites are granoblastic and weakly gneissic with mineral assemblage of hypersthene, diopside, plagioclase and minor biotite, amphibole and ilmenite. Some samples contain the intergrowth composed of labradorite and vermicular hypersthene, and some coarse-grained plagioclases of andesine and labradorite composition occasionally develop bytownite rims with vermicular hypersthene, indicating a possible presence of garnet. Presence of blastogabbroic texture and hypersthene with diopside exsolution lamellae in some samples suggests that the protolith of the granulite is norite or gabbro. On the basis of metamorphic research and thermobaric calculation, the evolution of the granulite xenoliths is summarized into the following stages： （1） Isobaric cooling of underplated noritic or gabbroic magma in the lower crust led to the formation of probable garnet-bearing medium-high pressure granulite. （2） These higher pressure granulites were adiabatically uplifted to upper crust by dioritic magma and transformed to low pressure two-pyroxene granulite during an isothermal decompression. （3） The two-pyroxene granulite underwent retrograde metamorphism of different degrees during an isobaric cooling process as a result of crystallization and cooling of the dioritic magma. The pyroxenite-dominated cumulates and the medium-high pressure granulites may have rejuvenated the lower crust during the early Mesozoic.

On Jan.31 of 2010,the Suining earthquake occurred at Suining City whch is located the center of Sichuan Basin.It is unusual for the strong earthquake to occur at the center of Sichuan Basin with a stable geotectonic environment and a low-level historical seismicity.The macro-epicenter of the earthquake is located at Moxi town of Suining city,Sichuan province,China.The earthquake intensity of the epicenter area is degree VII,and the long axis of the isoseismal line trends in NE orientation.The Suining earthquake caused the collapse or destruction of 460 family houses.The earthquake focal mechanism solution and records of the near-field seismographic stations showed the earthquake occurred at the reverse fault at a depth 34 km.Based on the waveform and focal mechanism,we consider the Suning earthquake is triggered by the reverse fault and not by the gravitational collapse or man-made explosive sources.Basing on seismic refraction profile and borehole,we consider that the earthquake is triggered by the backthrust fault of Moxi anticline rooted in detachments at a depth 3-4 km.Furthermore,we infer that tectonic mechanism of the Suining（Ms5.0） Earthquake is driven by the horizontal crustal shortening and stress adjustment on a shallow detachment after the Wenchuan（Ms 8.0） earthquake.

Many reefs of the Late Paleozoic have been discovered recently in the Hinggan-lnner Mongolia area. These reefs clearly are geographically extensive, and possess distinctive features and well-developed reef-facies. They have been found to contain five reef-building communities and were constructed in four periods. Colonial coral-algal reefs at Aohan and Chifeng represent a warm shallow-sea in the Carboniferous. Different reefs in the Xiwu Banner were formed in three periods： early Late Carboniferous, late Late Carboniferous and Early Permian. These reefs were built in warm sea conditions. Their buildup types include colonial coral frameworks, algae-buildings and lime-mud mounds. Bryozoan reefs in the Zhalaite and Dongwu banners were built in the late Middle Permian and thrived in a cold shallow-sea. All reefs grew independently on two kinds of sedimentary platforms, carbonate and carbonate-clastic mixed platforms. Four reef-forming periods occurred later from south to north, along a collisional course between the North China Plate and the Siberian Plate. These reefs can be arranged into three ＇reef-links＇ or reef zones that extend along plate margins. Among these, the Aohan-Chifeng reef-link indicates a northern margin of the North China Plate, the Zhalaite-Dongwu reef-link marks a southern margin of the Siberian Plate, and the Xiwu-Beishan reef-link reflects the former existence of some inter-plates. The strata of each reef-facies are thick and contain rich asphalt deposits. Overlapping and heteropic layers are very thick and contain dark oil/gas-rich horizons; TOC analyses verify that most of these are good hydrocarbon source rocks. This study shows that the study area is an excellent candidate for oil-gas exploration.