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1.
ＧＥＮＥＳＩＳＡＮＤＴＹＰＥＳＯＦＰＥＡＴＬＡＮＤＳ，ＣＨＡＮＧＢＡＩＭＯＵＴＡＩＮＳ，ＣＨＩＮＡTXＧＥＮＥＳＩＳＡＮＤＴＹＰＥＳＯＦＰＥＡＴＬＡＮＤＳ，ＣＨＡＮＧＢＡＩＭＯＵＮＴＡＩＮＳ，ＣＨＩＮＡＷｕＣｈａｏｄｏｎｇＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌ...  相似文献   

2.
ＭＩＣＲＯＳＴＲＵＣＴＵＲＡＬＦＥＡＴＵＲＥＳＯＦＤＵＣＴＩＬＥＳＨＥＡＺＯＮＥＯＮＴＨＥＮＯＲＴＨＥＲＮＭＡＲＧＩＮＯＦＨＯＨＸＩＬ，ＱＩＮＧ－ＨＡＩＰＲＯＶＩＮＣＥ，ＣＨＩＮＡTXＭＩＣＲＯＳＴＲＵＣＴＵＲＡＬＦＥＡＴＵＲＥＳＯＦＤＵＣＴＩＬＥＳＨ...  相似文献   

3.
《地质学报》1932,11(1)
The Annual Meetings of the past years were all held in Peiping. This was the first meeting held at Nanking at the invitation of National Central University. Fifty-four members were present, including Director W. H. Wong of the National Geological Survey, Prof. Y. C. Sun of National University, Peiping, Mr. T. O. Chu, acting Director of Geological Survey of Kwangtung and  相似文献   

4.
ＤＹＮＡＭＯＭＥＴＡＭＯＲＰＨＩＣＭＩＮＥＲＡＬＩＺＡＴＩＯＮＯＦＬＡＬＡＣＯＰＥＲＤＥＰＰＯＳＩＴ，ＨＵＩＬＩ，ＳＩＣＨＵＡＮＰＲＯＶＩＮＣＥＺｈｏｕＹｏｎｇＩｎｓｔｉｔｕｔｅｏｆＧｅｏｌｏｇｙ，ＡｃａｄｅｍｉａＳｉｎｉｃａ，Ｂｅｉｊｉｎｇ１０００...  相似文献   

5.
ＳＥＱＵＥＮＣＥＤＩＶＩＳＩＯＮ，ＦＥＡＴＵＲＥＳＯＦＳＹＳＴＥＭＳＴＲＡＣＴＳＡＮＤＳＴＲＡＴＩＧＲＡＰＨＩＣＭＯＤＥＬＯＦＳＨＡＨＥＪＩＥＦＯＲＭＡＴＩＯＮＩＮＱＩＢＥＩＳＡＧ，ＨＵＡＮＧＨＵＡＤＥＰＲＥＳＳＩＯＮTXＳＥＱＵＥＮＣＥＤＩＶＩＳＩＯ...  相似文献   

6.
1. Introduction Kurgan, a frontier station in the south foot of the Southwest Tianshan Mountains, is located on the NW margin of the Tarim Basin (Fig. 1). The Mesozoic coal-bearing molasses there is the most west Mesozoic outcrop of the Kuqa Depression, a tectonic unit of Tarim and its adjacent area. It is very difficult for geologist to access there. This results in the lack of geological works in this area. Meanwhile, only a few petroleum exploration works have been accomplished in t…  相似文献   

7.
Please refer to the attachment(s) for more details.  相似文献   

8.
1. Introduction In many parts of the world, the technique of electrical sounding has been used effectively for solving subsurface water problems in order to minimize drilling costs (e.g. Breusse 1963; Zohdy and Jackson, 1969; Zohdy, 1969; Zohdy et. al. 1984). During June 1999, resistivity surveys was made at the western Amman basin to provide some information about the thickness, lithology and tectonics of the subsurface layers and then to locate suitable drilling sites for water wells. T…  相似文献   

9.
1. Introduction The Ordos basin is a remnant inland basin on the western margin of the North China Plate and underwent several tectonic movements during its formation. There developed several assemblages of oil formation-reservoir-cover since Paleozoic. Of these, the Yanchang Formation (Upper Triassic) has important oil and gas reservoirs, especially in the Jingan Oilfield. Regional geology shows that, during the deposition of the Yanchang Formation (Upper Triassic), a huge inland lake …  相似文献   

10.
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11.
GENESIS OF COPPER MINERALIZATION IN THE WESTERN KOHISTAN ISLAND ARC TERRANE,NW HIMALAYA—HINDUKUSH, N. PAKISTAN  相似文献   

12.
In NW Himalayas, the suture zone between the collided Indian and the Karakoram plates is occupied by crust of the Cretaceous Kohistan Island\|Arc Terrane [1] . Late Cretaceous (about 90Ma) accretion with the southern margin of the Karakoram Plate at the site of the Shyok Suture Zone turned Kohistan to become an Andean\|type margin. The Neotethys was completely subducted at the southern margin of Kohistan by Early Tertiary, leading to collision between Kohistan and continental crust of the Indian plate at the site of the Main mantle thrust.More than 80% of the Kohistan terrane comprises plutonic rocks of (1) ultramafic to gabbroic composition forming the basal crust of the intra\|oceanic stage of the island arc, and (2) tonalite\|granodiorite\|granite composition belong to the Kohistan Batholith occupying much of the intermediate to shallow crust of the terrane mostly intruded in the Andean\|type margin stage [2] . Both these stages of subduction\|related magmatism were associated with volcanic and sedimentary rocks formed in Late Cretaceous and Early Tertiary basins. This study addresses tectonic configuration of Early Tertiary Drosh basin exposed in NW parts of the Kohistan terrane, immediately to the south of the Shyok Suture Zone.  相似文献   

13.
A PETROLOGICAL OVERVIEW OF THE KOHISTAN MAGMATIC ARC, NW HIMALAYA, N. PAKISTAN1　TahirkheliRAK ,MattauerM .ProustF ,etal.1979.In :GeodynamicsofPakistan[C].FarahA ,DeJongKA ,eds.GeolSurvPakistan ,Quetta ,1979.12 5～ 130 . 2　CowardMP ,WindleyBF ,BroughtonRD ,etal.In :CollisionTectonics[C]..CowardMP ,RiesAC ,eds.GeolSoc,London ,SpecPub ,1986 ,19:2 0 3～ 2 19. 3　BardJP ,MaluskiH ,MattePh ,etal.GeolBull ,PeshawarUniversity ,1980 ,13:87～ 93. …  相似文献   

14.
沿扬子地块西缘出露的一系列变质杂岩的构造性质及形成时代是分析华南地块大地构造属性的关键。这些杂岩均被初始为低角度的正断层所围限 ,具有变质核杂岩的构造性质 ,其剥露时间在177Ma左右。目前 ,对这一区域几个代表性杂岩体进行的系统的岩石学和地球化学分析表明 ,这是一套主体为与俯冲板块有关的岛弧型岩浆杂岩 ,其形成时代从 72 6～ 86 4Ma ,时间跨度在 10 0Ma以上。证明这些岩石的形成与地幔柱作用无关。上述结果与最近在Madagascar东北缘、Seychelles岛及印度的Malani的一条类似的变质岩浆杂岩带的地球化学与地质年代学研究结果完全吻合 ,这个构造带被解释为一条沿Mozambique洋东缘的巨大的向东俯冲的安第斯型俯冲 岩浆岛弧带。据此我们推测在Rodinia古大陆中 ,华南地块位于印度板块东北缘 ,其南东则可能与澳大利亚相接。  相似文献   

15.
STRUCTURAL AND THERMAL EVOLUTION OF THE SOUTH ASIAN CONTINENTAL MARGIN ALONG THE KARAKORAM AND HINDU KUSH RANGES,NORTH PAKISTAN  相似文献   

16.
LOW TEMPERATURE DATING OF HIGH MOUNTAIN ROCKS:(U-Th)/He AGES FROM HIGHER HIMALAYAN SAMPLES, EASTERN NEPAL1　HouseMA ,WernickeBP ,FarleyKA .DatingtopographyoftheSierraNevada ,California ,usingapatite (U Th) /Heages[J].Nature,1998,396 (5 ) :6 6～ 6 9. 2　HubbardMS ,Harrison .4 0 Ar/ 3 9ArageconstraintsondeformationandmetamorphismintheMainCentralThrustzoneandTibetanSlab ,EasternNepalHimalaya[J].Tectonics,1989,8(4) :86 5～ 880 . 3　HubbardMS …  相似文献   

17.
ABSTRACT The pressure-temperature and temperature-time paths derived for rocks in the Kohistan arc and adjacent Nanga Parbat-Haramosh massif record the dynamics of the collision between the island arc and the Indian plate. Studies of P-T-t paths show that the Kohistan arc was thrust over the Nanga Parbat-Haramosh massif at least 25 Ma ago, but not more than 30–35 Ma ago. Rocks in the Kohistan arc followed decreasing pressure paths, with the early metamorphism beginning at high pressures (9.5 kbar) and later metamorphism occurring at 8.0 kbar. In contrast, rocks in the Nanga Parbat-Haramosh massif (Indian plate) experienced increasing pressure and temperature paths. Prior to thrusting, the massif was at low pressures (4.0 kbar) and low temperatures (450°c). Later, the pressure and temperature increased to 8 kbar and 580°c. The authors interpret the convergence (to approximately the same pressure and temperature) of the P-T paths in the two terranes as being the result of thrusting and thermal equilibration between the thrust sheets. 40Ar/39Ar cooling ages of hornblendes and other geochronological data suggest that the time of peak metamorphism and hence the completion of thickening was approximately 30–35 Ma ago. Temperature-time paths show that after thrusting, during the period 25–10 Ma, the Kohistan arc and Nanga Parbat-Haramosh massif were uplifted at similar rates (0.5 km Ma). However, in the past 10 Ma the Nanga Parbat-Haramosh massif has been uplifted more rapidly than the adjacent Kohistan arc. Rapid uplift has been accommodated by late faults along the edge of the massif.  相似文献   

18.
The newly formed continental crust in southern Kamchatka was created as a result of the Eocene collision of the Cretaceous-Paleocene Achaivayam-Valagin island arc and the northeastern Asian margin. Widespread migmatization and granite formation accompanied this process in the Sredinny Range of Kamchatka. The tectonic setting and composition of granitic rocks in the Malka Uplift of the Sredinny Range are characterized in detail, and the U-Pb (SHRIMP) zircon ages are discussed. Two main stages of granite formation—Campanian (80–78 Ma ago) and Eocene (52 ± 2 Ma ago) have been established. It may be suggested that granite formation in the Campanian was related to the partial melting of the accretionary wedge due to its under-plating by mafic material or to plunging of the oceanic ridge beneath the accretionary wedge. The Eocene granitic rocks were formed owing to the collision of the Achaivayam-Valagin ensimatic island arc with the Kamchatka margin of Eurasia. In southern Kamchatka (Malka Uplift of the Sredinny Range), the arc-continent collision started 55–53 Ma ago. As a result, the island-arc complexes were thrust over terrigenous sequences of the continental margin. The thickness of the allochthon was sufficient to plunge the autochthon to a considerable depth. The autochthon and the lower portion of the allochthon underwent high-grade metamorphism followed by partial melting and emplacement of granitic magma 52 ± 2 Ma ago. The anomalously rapid heating of the crust was probably caused by the ascent of asthenospheric magma initiated by slab breakoff, while the Eurasian Plate plunged beneath the Achaivayam-Valagin arc.  相似文献   

19.
Variscan to Alpine magmatic activity on the North Tethys active Eurasian margin in the Caucasus region is revealed by 40Ar/39Ar ages from rocks sampled in the Georgian Crystalline basement and exotic blocs in the Armenian foreland basin. These ages provide insights into the long duration of magmatic activity and related metamorphic history of the margin, with: (1) a phase of transpression with little crustal thickening during the Variscan cycle, evidenced by HT-LP metamorphism at 329–337 Ma; (2) a phase of intense bimodal magmatism at the end of the Variscan cycle, between 303 and 269 Ma, which is interpreted as an ongoing active margin during this period; (3) further evolution of the active margin evidenced by migmatites formed at ca. 183 Ma in a transpressive setting; (4) paroxysmal arc plutonic activity during the Jurassic (although the active magmatic arc was located farther south than the studied crystalline basements) with metamorphic rocks of the Eurasian basement sampled in the Armenian foreland basin dated at 166 Ma; (5) rapid cooling suggested by similar within-error ages of amphibole and muscovite sampled from the same exotic block in the Armenian fore-arc basin, ascribed to rapid exhumation related to extensional tectonics in the arc; and finally (6) cessation of ‘Andean’-type magmatic arc history in the Upper Cretaceous. Remnants of magmatic activity in the Early Cretaceous are found in the Georgian crystalline basement at c. 114 Ma, which is ascribed to flat slab subduction of relatively hot oceanic crust. This event corresponds to the emplacement of an oceanic seamount above the N Armenian ophiolite at 117 Ma. The activity of a hot spot between the active Eurasian margin and the South Armenian Block is thought to have heated and thickened the Neo-Tethys oceanic crust. Finally, the South Eurasian margin was uplifted and transported over this hot oceanic crust, resulting in the cessation of subduction and the erosion of the southern edge of the margin in Upper Cretaceous times. Emplacement of Eocene volcanics stitches all main collisional structures.  相似文献   

20.
We report the following new40Ar/39Ar ages: 130–150 and 90–100 Ma from monzodiorite and tremolite-actinolite schist of the Kohistan Complex; 44±0.5, 39.7±0.2 Ma from dikes cutting the Ladakh-Deosai Batholith Complex; 130–145 Ma from a diorite in the Shyok melange; and 7.8±0.1 Ma from a late stage monzogranite of the Kärakorum Batholith. A 261±13 Ma age from gneiss of the Karakorum Batholith is of uncertain significance. These dates, previously published ones which we summarize here, and some Sr isotope data suggest the following, (due to subduction switching between the Indian and Asian margins during closing of the Tethys ocean): Late Cretaceous emplacement of the Dras-Kohistan Cretaceous Island arc, followed by rapid cooling between abut 85 and 45 Ma. A quiet phase tectonically on the northern Indian plate during the Palaeocene to early Eocene, when subduction was occurring on the Asian margin. Further southward thrusting of the Indian continental margin associated with the development of an Andean-type arc (the Ladakh-Desosai Batholiths) on the northern Indian margin during the Eocene. An Oligocene Andean arc (the Karakorum Batholiths) on the Asian margin, followed by Miocene collision of the two continents and intrusion of ‘true’ granites derived from partial melting of continental crust.  相似文献   

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