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1.
Since Late Proterozoic era, the Korean Peninsula has been evolved into a state with relatively stable regions and orogenic beltswhich were developed differently each other. The Late Paleozoic (Late Carboniferous-Early Triassic) sediments are well developed in the Korean Peninsula, and called the Pyongan System. The Pyongan System from Late Carboniferous to Lower Triassic is distributed in the Pyongnan and Hyesan-Riwon Basins, and Rangrim Massif, and divided into Hongjom (C2 ) , Ripsok (C2 ) , Sadong (C2-P1 ) , Kobangsan and Rokam ( Taezhawon) ( P2-T1 ) sequences. The sediments of the Tumangang Orogenic Belt are called Tuman System which is composed of the Amgi Series, consisting of clastic formation with mafic effusive material, overlaid by the Kyeryongsan Series, consisting mainly of mafic volcano sediments. The Songsang Series which rests on the Kyeryongsan Series mainly consists of clastic formation with minor felsic effusive material. In the Tuman- gang Orogenic Belt the tectonic movement, called Tumangang Tectonic Movement, occurred in the Lower Permian-Lower Triassic.  相似文献   

2.
In the Korean Peninsula the Meso-Cenozoic basins were mainly formed due to fault block and block movement. The Mesozoic fracture structures correspond basically to modem large rivers in direction. Such faults were usually developed to rift and formed lake-type tectonic basin, such as the Amrokgang-, Taedonggang-, Ryesonggang-, Hochongang-, Jangphari-, Susongchon-, Pujon-, and Nampho basins. The Mesozoic strata are considered to be divided into the Lower Jurassic Taedong System, Upper Jurassic Jasong System, Upper Jurassic-early Lower Cretaceous Taebo System, and the Upper Cretaceous-Paleocene ( Chonjaebong, Hongwon, Jaedok Series). The Cenozoic block movement succeeded the Mesozoic fault block movement. The Kilju-Myongchon Graben and Tumangang Basin, etc, are the basins related to the fault zones developed from the Oligocene to Miocene. In addition, the Tertiary basins were formed in many areas in the Miocene (e. g. Sinhung, Oro, Hamhung, Yonghung, Anbyon, Cholwon, etc). The Cenozoic sedimentation occurred mainly from the late Oligocene to Miocene. The Kilju-Myongchon Graben was the fore deep connected to the sea and the basins inclined in the Chugaryong Fault Zone are intramountain basins. Therefore, coal-beating beds and clastic rocks in the intramountain basins and rare marine strata and terrigenous clastic rocks are main sedimentary sequences in the Cenozoic.  相似文献   

3.
胶东半岛的原生金金属储量约占全国的1/7.郯-庐断裂两侧的地质差异由新太古代延续到早白垩世晚期,指示胶东半岛为一独立大地构造块体.结合大别-苏鲁超高压-高压变质带的被错开及该变质带的三叠纪同位素年龄峰值,郯-庐断裂的主活动期可限定在后三叠纪-早白垩世晚期.金矿的同位素年龄和半岛南部广泛的金矿化指示区域成矿主要发生在侏罗纪-早白垩世,乳山矿区的矿化蚀变特征则暗示成矿作用与变质热液无关;由于区内主变质期早于新元古代,故认为半岛的成矿起因于晚中生代大范围基底部分融熔及与此相关的岩浆热液活动,与欧亚陆缘演化有关.因此,胶东半岛的金矿与典型"绿岩型”金矿不可比,而火成岩密集区则应在找矿中加以重视.  相似文献   

4.
In the Korean Peninsula the Meso-Cenozoic basins were mainly formed due to fault block and block movement. The Mesozoic fracture structures correspond basically to modern large rivers in direction. Such faults were usually developed to rift and formed lake-type tectonic basin, such as the Amrokgang-, Taedonggang-, Ryesonggang-, Hochongang-, Jangphari-, Susongchon-, Pujon-, and Nampho basins. The Mesozoic strata are considered to be divided into the Lower Jurassic Taedong System, Upper Jurassic Jasong System, Upper Jurassic-early Lower Cretaceous Taebo System, and the Upper Cretaceous-Paleocene (Chonjaebong, Hongwon, Jaedok Series) . The Cenozoic block movement succeeded the Mesozoic fault block movement. The Kilju-Myonchon Graben and Tumangang Basin, etc, are the basins related to the fault zones developed from the Oligocene to Miocene. In addition, the Tertiary basins were formed in many areas in the Miocene ( e. g. Sinhung, Oro, Hamhung, Yonghung, Anbyon, Cholwon, etc) . The Cenozoic sedimentation occurred mainly from the late Oligocene to Miocene. The Kilju-Myongchon Graben was the fore deep connected to the sea and the basins inclined in the Chugaryong Fault Zone are intramountain basins. Therefore, coal-bearing beds and clastic rocks in the intramountain basins and rare marine strata and terrigenous clastic rocks are main sedimentary sequences in the Cenozoic.  相似文献   

5.
Petrological, chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants ( 〉3.4 Ga) of continental nuclei crust were formed in the Paleoarchean in the Rangrim Massif. In the massif, the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga, its important growing period was 2.8 - 2. 5 Ga. The subsequent expansion period of the Rangrim Massif was 2. 4 - 2. 2 Ga. The division events occurred in 1.85 Ga and in the Late Paleoproterozoic-Early Mesoproterozoic, respectively. Since then the massif was relatively stable. However, the last division of the Rangrim Massif occurred at 793 Ma.  相似文献   

6.
The Dabic-Sulu orogenic belt in central-eastern China is considered as a high-pressure and ultrahighpressure metamorphic belt that demensions are comparatively large,and formed as a result of the colli...  相似文献   

7.
常德-安仁断裂是湖南东部一条NW向大断裂。以大量的基础地质资料为基础,对该断裂的分段性特征进行了总结;基于断裂带印支期花岗岩成因及分布规律,提出其在中三叠世晚期印支运动主幕中的活动具有分段性。根据断裂带及其两侧地区构造特征以及出露地层和岩浆岩等方面的差异,将常德-安仁断裂分为安仁-衡山段(Ⅰ)、湘乡段(Ⅱ)、桃江段(Ⅲ)、常德-石门段(Ⅳ)4段,各段间以穿切深部地壳乃至地幔的NE向深大断裂为界。NE向深大断裂主要形成于加里东运动并具左行走滑,其将常德-安仁断裂切错为互不连通的多段,导致后者在中生代的构造运动具分段性。区域上晚三叠世花岗岩主要为后碰撞环境下深部地壳熔融形成的S型花岗岩。常德-安仁断裂带上晚三叠世花岗岩的分布特征指示该断裂在印支运动主幕中的活动具有明显的分段性:中三叠世印支运动主幕中断裂湘乡段深部发生剪切活动,在端部受限的条件下其运动幅度、剪切强度及相应的增温效应自该段中部向端部减小,导致晚三叠世的深部地壳减压熔融仅发生于湘乡段中段,相应的花岗岩体则出露于湘乡段中段和北段。这一构造-岩浆机制在安仁-衡山段和桃江段得到同样反映。常德-安仁断裂在印支期的分段运动,是先期贯通断裂被NE向深大断裂切错为多段后产生的"被动性"分段运动,有别于-般的多条小断裂发生、扩展并最终连接为一条大断裂的"主动性"断裂分段运动或分段生长。   相似文献   

8.
龙门山褶皱冲断带位于四川克拉通以东,被围限在扬子、华北和羌塘三大陆块拼贴构造间.以全工区地震精细解释为基础,结合野外调查,选取近东西向的剖面06fsc0003—02tjs1111线,利用平衡剖面法恢复天井山构造带的造山过程.结果表明:天井山构造带的演化可划分为伸展拉张成盆阶段(震旦纪—中三叠世末)、陆隆伸展演化阶段(晚三叠世—中侏罗世末)、挤压抬升剥蚀阶段(晚侏罗世—现今)3期.根据生储盖组合和油气运移条件,认为自元古代以来最大主应力性质发生多次改变,控制构造变形、生储盖组合分布及厚度、断裂特征和油气运聚.印支期冲断带下盘(现今天井山背斜前翼下部)发育形成于印支期晚期的冲起构造,其内断层发育,将二叠系、志留系及寒武系烃源岩与二叠系储层和圈闭串通,有利于烃类的运聚,且有飞仙关组泥岩作为直接盖层,保存条件较好,是油气集聚的有利部位.该研究能够加深对龙门山褶皱冲断带油气分布预测的认识,对油气勘探具有指导意义.  相似文献   

9.
Precambrian crustal evolution in Rangrim Massif , Korean Peninsula   总被引:2,自引:0,他引:2  
Petrological, chronological and geotectonic geological analysis of Precambrian metamorphic rock in Korean Peninsula shows that the remnants ( > 314 Ga) of continental nuclei crust were formed in the Paleo-archean in the Rangrim Massif. In the massif, the main formation ages of continental crust range from 3.2 Ga to 2.5 Ga, its important growing period was 2.8 - 2.5 Ga. The subsequent expansion period of the Rangrim Massif was 2.4 - 2.2 Ga. The division events occurred in 1.85 Ga and in the Late Paleoproterozoic-Early Mesoproterozoic, respectively. Since then the massif was relatively stable. However, the last division of the Rangrim Massif occurred at 793 Ma.  相似文献   

10.
扬子地台与华南南盘江盆地大贵州滩三叠系沉积演化史   总被引:1,自引:0,他引:1  
扬子地台是一个横跨华南地块的以浅海沉积为主的大型碳酸盐岩台地,南盘江盆地是发育在扬子地台碳酸盐岩台地背景之上的一个沉积盆地,从晚元古代到晚三叠世长期海相沉积演化历史中,扬子地台-南盘江盆地体系经历了多次重要的构造演化阶段.扬子地台从晚元古代到早三叠世末期一直保持为一个稳定的碳酸盐岩台地,在中三叠世末期扬子地块整体抬升,海平面下降,形成了遍及扬子主体的拉丁期大海退,从而使扬子地块大部分地区抬升为陆.南盘江盆地位于华南地块南缘,从晚元古代到晚三叠世沉积了一套厚度巨大的海相碳酸盐岩,晚三叠世发育了一套硅质碎屑的浊流沉积,区域沉积也由此转化为河流相沉积.二叠纪和三叠纪碳酸盐岩地层记录了碳酸盐岩台地长期演化历史及其特征多样的沉积建造和沉积环境,而硅质碎屑流和构造沉降速率的变化反映了盆地在三叠纪期间经历的聚合构造和前陆盆地发展过程.在三叠纪时期扬子地台沿西南-北东方向从云南围绕南盘江盆地向贵州延伸,在南盘江盆地中发育了几个孤立的碳酸盐岩台地,包括位于贵州南部和广西境内的大贵州滩和崇左-平果台地.南盘江盆地在晚二叠世发生过一次区域性的海侵事件,早三叠世时期扬子地台和几个孤立台地为由鲕粒边滩组成的低角度斜坡,中三叠世(安尼期)变为由Tubiphytes边礁组成的陡倾斜坡.盆地范围内斜坡变陡激发了Tubiphytes礁和其它的生物体发育,而且它们组成了稳定碳酸盐岩台地的边缘.位于扬子地台西部地区的关林和贞丰一带与最北部的孤立台地(大贵州滩)在安尼期发育了陡倾的边礁.在拉丁期,扬子地台在关林一带进积并与盆地碎屑沉积互层穿插沉积,而位于贞丰的台地边缘出现了由断层控制的地貌特征.与此同时,扬子地台东部(贵阳)由侵蚀滑塌边缘变为进积边缘,向盆地内部进积充填形成了超过600 m的碎屑沉积.但是,与扬子地台不同,位于最北部的孤立台地(大贵州滩)在拉丁期由加积边缘礁变为起伏明显的侵蚀陡崖和饥饿盆地边缘.晚三叠世(卡尼期)扬子地台西部下沉并被晚三叠世浊流沉积埋藏,而扬子地台东部地区在被硅质碎屑沉积埋藏之前持续沉积了一套浅水碳酸盐岩沉积.孤立台地为从南到北逐渐变陡的边缘沉积,而且发育了多个小丘,其中南部地区早期沉降后来被硅质碎屑沉积埋藏,而北部地区到后期下沉.与扬子地台西部一样,最北部的孤立台地(大贵州滩)在晚三叠世下降被碎屑沉积埋藏.以上这种差异源于华南地块南缘因构造聚合作用导致的盆地南部地区不同沉降速率.大贵州滩是盆地中演化历史最长的孤立台地,穿过大贵州滩孤立台地内部和边缘的两条正交剖面显示出了一个被断层切断的向斜构造,这样就很容易识别其沉积建造特征及演化历史.大贵州滩发育的整合的二叠系-三叠系界线剖面以及从早三叠世到中三叠世生物复苏阶段连续的巨厚沉积,使其成为一个研究二叠世末期生物大绝灭期间的海相环境以及生物生态条件最为理想的地区.  相似文献   

11.
华南大陆部分中新生代大地构造单元属南华造山带,可分为NW-NWW向的滨特提斯褶皱系和NE向的滨太平洋褶皱系.滨太平洋褶皱系包含东南大陆边缘弧褶皱带和东南大陆边缘弧后褶皱带,是晚三叠世以来多期次继承性造山运动累积叠加形成的.主要褶皱时代,在陆缘弧褶皱带是晚侏罗-中始新世;在陆缘弧后褶皱带是中晚始新世之交.讨论了华南及邻区中新生代大地构造格局及其成因和羽状对称特点,以及陆壳减薄板段、主动大地构造单元和被动大地构造单元几个概念.  相似文献   

12.
Fenneropenaeus chinensis distributed in the Yellow Sea and Bohai Sea of China and the west coast of the Korean Peninsula. Different geographical populations represent potentially different genetic resources. To learn further the characteristics of different geographical population, crosses among two wild and three farmed populations were produced. The two wild populations were from the Yellow Sea and Bohai Sea (WYP), and the west coast of the Korean Peninsula and coast (WKN). The three farmed populations included the offspring of first generation of wild shrimp from coast in Korea (FKN), the Huang Hai (the Yellow Sea in Chinese) No. 1 (HH 1), and JK98. The phenotypes growth and survival rates of these populations were compared to confirm the feasibility for crossbreeding. The body length (BL), carapace length (CL), carapace width (CW), height of the second and third abdominal segment (HST), width of the second and third abdominal segment (WST), length of the first abdominal segment (LF), length of the last abdominal segment (LL), live body weight (BW), and survival rate were measured. Different combinations were statistically performed with ANOVA and Duncan's Multiple significant difference (P<0.05) in BL, CL, HST, LL, and BW; and insignificant difference (P0.05) in other growth traits and survival rate. The results of Duncan's Multiple Range Test are that BL and CL of was the best combination in all growth traits. Therefore, hybridization can introduce the variation to base populations. The systematic selection program based on additive genetic performance may be more effective than crossbreeding.  相似文献   

13.
Studies on long-term change of cropland is of great significance to the utilization of land resources and the implementation of scientific agricultural policies. The Korean Peninsula, adjacent to China, plays an important role in the international environment of Northeast Asia. The Korean Peninsula includes South Korea and North Korea—two countries that have a great difference in their institutions and economic developments. Therefore, we aim to quantify the spatiotemporal changes of croplands in these two countries using Landsat Thematic Imager(TM) and Operational Land Imager(OLI) imagery, and to compare the differences of cropland changes between the two countries. This paper take full advantage of ODM approach(object-oriented segmentation and decision-tree classification based on multi-season imageries) to obtain the distribution of croplands in 1990 and 2015. Results showed that the overall classification accuracy of cropland data is 91.10% in 1990 and 92.52% in 2015. The croplands were mainly distributed in areas with slopes that were less than 8° and with elevations that were less than 300 m in the Korean Peninsula. However, in other region(slope 8° or elevation 300 m), the area and proportion of North Korea's croplands were significantly higher than that of South Korea. Croplands significantly increased by 15.02% in North Korea from 1990 to 2015. In contrast, croplands in South Korea slightly decreased by 1.32%. During the 25 years, policy shift, economic development, population growth, and urban sprawl played primary roles for cropland changes. Additionally, the regional differences of cropland changes were mainly due to different agriculture policies implemented by different countries. The achievements of this study can provide scientific guidance for the protection and sustainability of land resources.  相似文献   

14.
托来南山中段晚三叠世出露比较完整,但研究程度较低。该文主要对中祁连上日木策尔地区晚三叠世开展研究。研究区晚三叠世分为阿塔寺组和尕勒得寺组。前者与下伏托赖岩群呈断层接触,主要以河流相粗粒长石石英砂岩为主,夹灰色、紫红色粉砂岩和灰黑色粉砂岩,发现有遗迹化石(垂直潜穴);后者主要为淡水湖泊相—灰黑色粉砂岩、钙质粉砂岩夹黑色页岩及细粒长石石英砂岩,局部夹有煤线(木里地区),在灰黑色粉砂岩中发育有植物化石Neocalamites rugosus和Danaeopsis fecunaa系华北延长群的标准分子,在黑色页岩层位中产化石叶肢介类Loxomegaglypta Novojilov属等。研究区二组的接触关系为整合接触,中间并没有发现沉积间断。  相似文献   

15.
湖南省内生矿产资源丰富,内生成矿事件主要有加里东期(以志留纪为主)、印支晚期(晚三叠世)、燕山中晚期(晚侏罗世-早白垩世)等3期。以区域矿产资料为基础,结合大地构造、成岩成矿年龄、矿床成因机制等研究成果,对上述3期内生成矿事件的构造格局控矿特征和动力机制进行探讨。①受加里东运动自东南向西北扩展以及深部岩石圈结构差异控制,加里东期湖南省自东南往西北分为成矿特征有别的3个构造带。湘中-湘东南构造岩浆带(Ⅰ)发生后碰撞花岗质岩浆活动,于局部产生与岩浆活动相关的W、萤石等成矿作用;雪峰构造带(Ⅱ)东部的雪峰冲断带(Ⅱ1)形成了以构造活化成因为主的金矿和锑金矿;雪峰构造带(Ⅱ)西部的武陵低缓褶皱带(Ⅱ2)及湘西北构造抬升带(Ⅲ)内形成了与寒武纪同沉积断裂活动、加里东运动后的伸展活动以及相应的热液活动有关的汞铅锌矿。②印支晚期受深部岩石圈结构差异控制,湖南省自东南至西北分为3个构造带:湘中-湘东南构造岩浆带(Ⅰ)因后碰撞减压熔融而发生大规模花岗质岩浆活动,从而于其东南部形成钨锡铅锌多金属矿床,西北部形成锑金钨多金属矿床;雪峰构造带(Ⅱ)可能无内生热液成矿作用;湘西北褶皱带(Ⅲ)发育小型脉型铅锌矿。③燕山中晚期,湖南省自东南往西北分为3个构造带:湘中-湘东构造岩浆带(Ⅰ)受岩石圈拆沉、软流圈上隆、陆内碰撞后期增温减压、俯冲板块崩塌等深部构造作用控制而发生大规模花岗质岩浆活动,形成了大量的有色金属矿床和金矿床;雪峰西部构造带(Ⅱ)成矿作用弱,局部存在Au、Hg成矿作用;湘西北褶皱带(Ⅲ)发育少量低温热液充填型萤石矿和砷矿。  相似文献   

16.
Fractal theory was applied to a preliminary discussion of the fractal character and formation mechanism of the coastline of the bedrock coast of China on the basis of GIS ( Geographical Information System). Some significant conclusions were drawn : ( 1 ) The fractal dimensions of the coastline and linear structures of Liaodong Peninsula are 1.0093 and 1.0246 respectively, those of Shandong Peninsula are 1.019 and 1.021 respectively, etc. (2) The fractal dimensions of coastlines of Liaodong Peninsula, Shandong Peninsula, Zhejiang and Fujian-Guangdong tend to increase with the spatial change from north to south. (3)The regional linear structures( including faults)control the basic trends and fractal dimensions of coastlines as a whole in the regions of the bedrock coast of China : the more the controlling effect of linear structures, the smaller the fractal dimensions of coastlines. (4)The substantial constituents of coast and biologic function both play an important role in affecting the fractal dimensions of coastlines of Liaodong Peninsula,Shandong Peninsula, Zhejiang, Fujian-Guangdong and Taiwan Island.  相似文献   

17.
山东是华北地区较早接受晚古生代地层沉积的地区,分布于沂沭断裂带以西地区,自下而上划分为月门沟群和石盒子群,富含动植物化石和煤炭、铝土矿等矿产资源。该套地层不整合于奥陶系之上,顶部遭受风化剥蚀,被三叠系不整合覆盖,在不同地区地层厚度、岩性及含矿性特征差别较大。沉积环境由海相-海陆交互相向陆相演化,主要分为海洋环境、海陆过渡环境、湖泊环境、沼泽环境和河流环境。  相似文献   

18.
The Wulonggou area located in the Eastern Kunlun Orogen in NW China is characterized by extensive granitoid magmatism,ductile faulting and orogenic gold mineralization.The Huanglonggou granodiorite is cut by an orogenic gold-bearing fault.This study investigated the major and trace-element compositions,zircon U-Pb dates and zircon Hf isotopic compositions of the Huanglonggou granodiorite.One Huanglonggou granodiorite sample yielded a weighted mean U-Pb zircon age of~221 Ma(Carnian).The Carnian granodiorite is metaluminous,with high alkalis contents of 6.37%--8.86%,high Al_2O_3contents of 15.41%--16.19%,high Sr contents of(426--475)×10~(-6),relatively high Sr/Y ratios,high(La/Yb)_Nvalues and low HREE,suggesting an adakite type high-Si O_2granite.The Huanglonggou granodiorite sample has zirconε_(Hf)(t)values ranging from-4.4 to+1.1.These Hf isotopic data suggest that the Carnian granodiorite was likely derived from the partial melting of subducted Paleo-Tethys oceanic slab.It is suggested that the Late Triassic granodiorite was emplaced during the northward subduction of Paleo-Tethys oceanic slab.Orogenic gold mineralization in the Wulonggou area formed after the emplacement of the Late Triassic intrusive rocks.  相似文献   

19.
铁岭凡河地区元古宙地层始于凡河元古宙坳拉谷沉积,根据岩石地层学、生物地层学、年代地层学等研究成果,结合现代层序地层学理论,自下而上划分六个层序,即关门山层序,虎头岭层序、二道沟层序、石门层序、杨士屯层序、于北沟层序。每个层序仅由海侵体系域和高水位体系域组成,分别代表海侵退积地层结构和海退进积地层结构,而中间饥饿段则以加积为主。各层序间均为不整合,其类型包括海岸暴露带和海侵面。在此基础上,建立了区域地层格架。  相似文献   

20.
The geochemical features of the monzonitic granite in Qimantage Hutouya deposit area,Qinghai,in respect to the mineralization,suggest that this granite belongs to weak peraluminous and high-k calc alkaline rock series. The REE of the samples show right slope with obvious LREE/HREE differentiation and negative Eu abnormity. The trace elements show enrichment of LILE( Rb,Th,U,La,Nd),and deleption of Ba,Sr,Nd,P,Ti. The Sr-Nb isotopic data indicate that the magma source is mainly aluminosilicate lower crust with a small amount of new crustal materials. The weighted mean zircon U-Pbage of the Hutouya monzonitic granite is 221±1.7 Ma,belonging to Late Triassic. The Hutouya monzonitic granite was formed in the tectonic setting of transition from compression to extension during Middle-Late Triassic.  相似文献   

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