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1.
Ancient mtDNA data of human remains were analyzed from four early Iron Age Tarim Basin sites (Yuansha, Zaghunluq, Sampula and Niya) in the southern Silk Road region. Haplogroup distributions show that ancient Tarim Basin population was comprised of well-differentiated Western and Eastern matrilineal lineages. Some West lineage of Tarim Basin population originated from Near East and Iran region. Of the East lineages, North and Northeast Asia originated lineages were the main components, and a few Southeast Asian lineages also existed, which indicated a more extensive origin and a more complex admixture. The genetic structure of ancient Tarim Basin population is relatively close to the modern populations of Xinjiang, which implied that the early Iron Age is an important period during the formation of the modern Xinjiang population.  相似文献   

2.
Orogenesis of the Qinghai-Tibetan Plateau,which occurred in a stepwise manner,contributed to the extreme aridity of the Tarim Basin,resulting in vulnerable and unstable ecosystems.Quaternary climatic oscillations may have affected the ecosystems and,consequently,the distributions and genetic structuring of the Tarim Basin’s biota.We used nucleotide sequence data from 2 mitochondrial (mt) DNA genes (Cyt b and the D-loop) to test hypotheses associated with the matrilineal and demographical histories of the Tarim Basin’s endemic Yarkand hare (Lepus yarkandensis).Range-wide sampling involving 20 populations and 224 individuals detected 126 haplotypes that clustered into 5 major lineages in both the phylogenetic tree and median-joining network.Populations from the northern and eastern Tarim Basin shared a similar history,as did those from the western and southern regions.Demographical analysis and genetic diversity estimations suggested that the western and southern regions might have served as glacial refugia for the Yarkand hare during Quaternary climatic oscillations.The distribution of the Yarkand hare,especially in the northern and eastern parts,probably represented 3 postglacial colonization events,dated to 0.21,0.090 and 0.054 MYA,which corresponded to known interglacial periods.Given the relatively complete geographic isolation between the eastern and southern populations,the Yarkand hare likely dispersed during postglacial periods from the southwest to the north,and then onward to the east.The absence of water likely forced the species into refugia,and this differed from other Pleistocene biogeographical drivers.The demographical and historical patterns have important implications for conservation.  相似文献   

3.
以沉积大地构造背景分析为基础,指出塔里木板块南缘由拉张背景转变为挤压,大地构造运动造成的东西向坳隆相间的古地形控制了塔里木盆地内柯坪塔格组的沉积格局和沉积发育史.结合沉积相的精细解释,将柯坪塔格组划分为潮坪-陆棚-潮坪三个沉积演化阶段.  相似文献   

4.
在牙形石生物地层的基础上,利用塔里木盆地塔北隆起钻井全岩碳同位素数据,结合其他学者公布的碳同位素曲线,探讨了塔里木盆地奥陶纪碳同位素波动特征,并与世界其他地区进行对比。塔里木盆地奥陶纪特马豆克阶-达瑞威尔阶早期碳同位素波动较弱,缺乏可全球对比的波动标志。达瑞威尔阶中期和凯迪阶早期发育明显的碳同位素正漂移,分别对应于国际上的中达瑞威尔阶碳同位素正漂移(MDICE)和加顿伯格碳同位素正漂移(GICE),能够进行全球对比。桑比阶早期牙形石 Pygodus anserinus 带内发育波动幅度达1.4‰的正漂移,其可能仅在部分地区分布,暂时命名为早桑比阶碳同位素正漂移(ESICE)。凯迪阶中后期碳同位素波动特征目前还不清楚,晚奥陶世赫南特阶碳同位素正漂移(HICE)在塔里木盆地也未见报道。MDICE 和 GICE 可作为塔里木盆地中上奥陶统的等时对比标志。  相似文献   

5.
大风对新疆沙尘暴的影响   总被引:14,自引:1,他引:13  
选取1961-1999年新疆90个气象观测站的气表-1资料,对比分析了沙尘暴及大风的时空分布特征,探讨大风对沙尘暴发生的贡献及沙尘暴发生时的最多风向和最低风速指标。分析发现,新疆沙尘暴与大风的地理分布刚好相反,沙尘暴多的地区大风较少,但有着基本一致的气候变化趋势。大风对沙尘暴的贡献北疆大于南疆。沙尘暴发生时的最多风向明显指示出引发沙尘暴的天气系统来向。引起沙尘暴的最低风速指标,北疆及东疆超过10m/s,南疆的吐鄯托盆地和焉耆盆地为10m/s,塔里木盆地为6~8m/s,盆地南缘只有6m/s.  相似文献   

6.
Structural characteristics and petroliferous features of Tarim Basin   总被引:2,自引:1,他引:2  
Using the modern tectonic geology theories andmethods such as the plate tectonic analysis, the paleo-struc-ture analysis, the structural-Iithofacies analysis, and the faultrelated fold and petroleum system, and combining with theseismic data, well drilling data and the circumferential fieldgeology, study on the structural characteristics and petro-leum prospect in the Tarim Basin has been carried out. Re-sults show that the Tarim Basin is a large superimpositionand combination basin with continental crustal basement,composed of a Paleozoic craton and Meso-Cenozoic forelandbasins. The characteristics of the basin are: the kernel partof the basin is the marine facies Paleozoic craton, superim-posed 4 continental facies foreland basins. Though the scaleof the paleozoic craton of the Tarim Basin is relatively small,the structure is steady. The petroleum prospect of the Paleo-zoic craton is: multiphase pool-generation and accumulationcontrolled by ancient uplift. The Meso-Cenozoic forelandbasins in the Tarim Basin, which are distributed on the era-tonic circumference and are a long-term subsidence, turnedinto rejuvenated foreland basins after the Meso-Cenozoicperiod. The petroleum prospects are: coal-bed generatinghydrocarbon, abundant natural gas, pool-generation in laterand recent periods, the oil and gas distribution controlled bythe foreland thrust belt. The structural characteristics ofTarim provide it with a superimposition and combinationpetroleum system of multiple resources, multiple reservoirsand multiphase pool-generation. The oil and gas explorationprospect covers two large fields: the Paleozoic craton and theMeso-Cenozoic foreland thrust belt.  相似文献   

7.
A ca. 4000a decadal-resolution climate proxy record of the mean grain-size from a lake (or mash) sediment at the southern margin of the Tarim Basin, correlates visually with the atmospheric 14C record from tree ring (residual △^14C, solar proxy) and the GISP2 ice core δ^18O record (temperature proxy). In general, △^14C maxima (solar minima) are coincident with cold (wet) periods in the study area and cold periods in the Greenland ice core. Power spectrum analysis revealed statistically significant periodicities of 196a, 121a, 97a, 62a, 45a and 33--30a, which are similar to those principal solar-oscillation periods as inferred from the atmospheric radiocarbon and other proxy records. Possible solar forcing is addressed to be the main driving forcing of climate change in the southern margin of Tarim Basin.  相似文献   

8.
通过对塔里木盆地巴楚组沉积格局与沉积演化的剖析,试图为巴楚组有利储集砂体和储盖组合预测提供新的思路。根据穿时普遍性原理认为巴楚组的东河砂岩段和下泥岩段为全盆地范围内穿时的岩石地层单元,生屑灰岩段可视为良好的时间-岩性标志层。以沉积大地构造背景分析为基础,指出塔里木盆地包含了克拉通边缘拗陷和克拉通内拗陷两个原型盆地,大地构造运动造成的西低东高的古地形以及自西向东的渐进式海侵,控制了塔里木盆地内巴楚组的沉积格局和沉积发育史。结合沉积相的精细解释,将巴楚组划分为四个沉积演化阶段:初期为初始海侵沉积阶段,早期是碎屑滨岸—陆棚发育阶段,中期主要为浅海碎屑陆棚发育阶段,晚期以发育碳酸盐岩台地沉积阶段为特色。  相似文献   

9.
Extensive lacustrine deposits in the eastern Tarim Basin provide records of climate change influenced by the westerly winds and the Asian monsoon. To char- acterize the evolution of climate change in this region, we analyze elemental concentrations of barium (Ba) from the Ls2 drill core of Lop Nor, a paleo-lakebed located in the eastern Tarim Basin. Biogenic Ba concentrations from this drill core display a large-amplitude oscillation that gener- ally follows a pattern similar to that of Artemisia content and ostracod assemblages, suggesting that is may serve as an index for climate change experienced in the basin. Our results indicate that biogenic Ba is especially sensitive to precipitation. All climatic proxies served in this study vary significantly over late Miocene to early Pleistocene time period. Strong aridification of eastern Tarim in the late Miocene to the early Pliocene may be attributed to a lati- tudinal shift in the westerly winds, which would have resulted in more moisture transported to southern and eastern Tibet. The growth of the Himalaya and Tibetan Plateau may have acted as an orographic barrier that blocked moisture sourced in the south from the northern margins of the plateau. We link weaker aridification in the late Pliocene to an increased intensity of the Indian Monsoon.  相似文献   

10.
Based on the multiple-epoch Global Positioning System observations during a period from 1992 to 1999, we document directly a rapid crustal shortening of ~20 mm/a across the western Tianshan Mts. (76°E), in contrast to a 4 mm/a convergent rate across the eastern Tianshan Mts. (87°E)and the north-south convergence across the mountain belt descends laterally from west to east. The direction of current crustal movement inferred by GPS sites along the southern flank of the Tianshan Mts. is approximately perpendicular to the easterly-trending mountain belt, indicating that the Tarim Basin thrust almost rightly into the Tianshan Mts. The Tarim Basin accommodates nearly no or a minor, if any, crustal deformation and rotates clockwise, as a rigid body in a whole, at a rate of 0.64°/Ma around a Euler pole at 95.7°E, 40.3°N (Anxi, Gansu) with respect to the stable Siberia. The relative motion between the Kazakh platform and the Dzungarian Basin is quite apparent. The Dzungar should be regarded as an independent active block from the view of the Asia tectonic settings.  相似文献   

11.
综合地震、测井、岩心、露头等资料,提出寒武纪—早奥陶世时期塔里木西南部发育台地边缘斜坡带.该斜坡带沿坎地里克—叶城—胜和2井—玛参1井连线一带呈近东西向展布,整体表现为退积型台缘缓斜坡.在寒武纪—早奥陶世的不同时期,该斜坡带性质和分布位置略有变化,寒武纪为宽缓斜坡,早奥陶世为弱镶边缓斜坡,斜坡带具有向北部台地逐期缓慢迁移的特点.塔西南台缘坡折带的存在表明玛南—和田河地区台缘高能相带和塔西南深水陆棚相带存在的可能性,对该区的烃源岩和储层评价预测具有重要意义.  相似文献   

12.
针对塔北和巴楚地区下丘里塔格群白云岩储层特征的差异问题,通过岩芯描述、薄片鉴定、阴极发光、扫描电镜、物性分析以及压汞等资料从岩石学、储集空间、物性及孔隙结构几个方面进行研究。结果表明:塔北地区主要为晶粒白云岩和颗粒白云岩;储集空间以晶间孔、晶间溶孔、溶蚀孔洞和裂缝为主,储集空间类型组合多样;喉道主要为粗-细喉型,分选好,孔喉分布均匀,连通性较好,物性较好;此外该区构造破裂作用和岩溶作用发育,也改善了储层物性。巴楚地区以晶粒白云岩和泥微晶白云岩为主;溶蚀孔洞、裂缝的发育程度和规模不如塔北地区,储集空间类型组合较单一;喉道多为细-微喉型,分选差,孔喉分布极不均匀,连通性差,物性较差。塔北地区白云岩储层物性好于巴楚地区,造成该差异的原因主要是受到了沉积作用和成岩作用的共同影响。  相似文献   

13.
古盐度计算与古地理恢复在塔里木盆地钾盐勘探中的应用   总被引:2,自引:0,他引:2  
探讨非传统方法在塔里木盆地寻找钾盐,尝试通过古盐度计算和古地理恢复来确定(漏)湖相沉积中心,同时结合元素地球化学特征分析与古地理、古盐度的耦合关系,对塔里木盆地固体钾盐矿有利发育区进行预测,认为发育深水(漏)湖相的大宛其地区岩盐体最厚,古盐度值、K+含量和澳氯系数也最高,并从深水(漏)湖→浅水(漏)湖→(漏)湖边缘呈逐...  相似文献   

14.
Due to the importance of the Gloeocapsomorpha Prisca (G. prisca)-enriched source rocks, which belong to Kukersite-type source rocks in the Lower Paleozoic Ordovician strata, it has received great attentions during the petroleum exploration as to whether there are the Kukersite-type source rocks developed in the major hydrocarbon source strata of the Upper and Middle Ordovician in the Tarim Basin. Using pyrolysis-gas chromatography-mass spectrography to analyse kerogens from source rocks in the lime- mud mound with moderate maturity, study reveals that there are the Kukersite-type source rocks in the Ordovician strata of the Tarim Basin. The pyrolysis products showed a low content of 〉n-C19 normal alkanes with a significant odd-even predominance between n-C13 and n-Cl7, long-chain alky substituted alkylbenzene and alkylthiophene isomers and distinctive distribution of 5-N- alkyl-1, 3-Benzenediol and its homologous. Based on the geographic environment characteristics of G. Prisca, the molecular dis- tributions of crude oil from the Lower Paleozoic petroleum systems in the Tarim Basin and characteristics of kerogen pyrolysis products from the Middle and Upper Ordovician source rocks, the results suggested that it is less possible to develop the G. Pris- ca-enriched Kukersite-type source rocks in the major hydrocarbon source rocks in the Middle and Upper Ordovician strata in the Tarim Basin. However, the benthic macroalga and planktonic algae-enriched source rocks are the main contributors.  相似文献   

15.
全球气候变化与塔里木盆地古城绿洲演变关系   总被引:1,自引:0,他引:1  
我国西部地区地形复杂,气候的地域差异性大.特别是青藏高原的突起给塔里木盆地的环境带来了巨大的变化,导致盆地气温降水的突变.从而使塔里木盆地水流分布状态发生改变,导致盆地中原有的古绿洲的蜕变,进而直接影响到整个人类的发展历史.历史研究表明,塔里木盆地气候服从于全球气候变化,并且与某些人文事件,特别是古城绿洲兴盛与消亡有着十分一致的耦合关系.所以,全球环境变化对古城绿洲发展影响重大.  相似文献   

16.
通过对塔里木盆地前震旦-石炭纪构造演化与地层组合特征的分析研究,将该盆地构造和地层系统划分为2大组合系统5个构造-地层组合.前震旦系为混合片麻岩、浅变质岩组成的地台基底,震旦纪发生板内裂陷形成坳拉槽,早寒武世-奥陶纪和石炭纪是盆地两次大的海侵期,沉积了富含烃类的碳酸盐岩建造,志留-泥盆纪为克拉通边缘隆升阶段,发育浅海相碎屑岩及碳酸盐岩建造.  相似文献   

17.
柴达木盆地西部阿尔金山前中、下侏罗统暗色含煤地层发育,对其沉积及展布特征认识不够是导致该区侏罗系油气勘探停滞不前的主要原因。以古水流分析为主要手段。结合地表露头、地层残留厚度及钻井资料对该区中、下侏罗统的展布特征及其对油气的控制作用进行了研究。结果表明,早、中侏罗世在古阿拉巴斯套山与古昆仑山之间发育一个大的近东西向展布的沉积坳陷(古泛茫崖坳陷)。坳陷的沉积中心在古阿尔金山区,西北部边界越过占阿尔金山区与塔东南中、下侏罗统沉积连为一体,东北部边界位于阿拉巴斯套地区,南部边界在红柳泉-煤沟-黑石山-月牙山一线。山前斜坡带分布多为冲积扇、沼泽化冲积平原等边缘相粗碎屑沉积,烃源岩不发育;而山前带清水沟-月牙山北一线湖相暗色泥页岩发育,为中等烃源岩,具备一定的生烃能力。该区油气勘探应以山前带为主,适当靠近阿尔金山的清水沟和月牙山西是两个有利勘探区。  相似文献   

18.
根据现代沉积学和层序地层学理论,以塔里木盆地志留系大量的岩心、测井和地震资料为基础,开展地层划分与沉积演化研究.塔中地区志留系分为下统柯坪塔格组沉积、塔塔埃尔塔格组、经历碎屑岩潮坪(局部发育扇三角洲)—内陆棚(泻湖)沉积演化.研究成果对于塔里木盆地储层展布及储盖组合具有参考价值,便于指导下一步油气勘探.  相似文献   

19.
针对新疆环塔里木盆地的风能、光伏新能源送出现状,提出采用多端柔性直流输电方式进行新能源外送。从电压等级的选择、柔性直流与高压交流、传统直流输电方式对比,分析环塔地区新能源外送采用柔性直流输电方式的可行性。针对环塔新能源柔性直流送出,设计送端、受端各换流站的控制方式和对环塔交流电网等值建模。最后通过PSCAD/EMTDC搭建送端风电场、光伏电站和受端环塔750kV交流电网仿真模型,并将其组成三端柔性直流系统实现环塔盆地新能源的消纳,通过仿真分析动态特性,验证可行性。  相似文献   

20.
为了对塔里木盆地英买2~3构造侏罗系至志留系的测井储层与油气资源进行研究和评价,描述了该构造上侏罗系至志留系各地层的基本电性特征;进行了构造上及周边井重要层系地层的构造倾角和古水流研究。通过岩心物性分析和油气描述,结合地层对比和地层倾角资料的研究,结果表明:英买2~3井区侏罗系地层从北西向南东逐渐抬升;横向上,古水流方向是南东东—北西西,物性特征是北西往南东逐渐变好,标识物源方向与古水流方向一致;纵向上,底部物性较中上部好,说明了沉积时底部较中上部水动力强的特点;英买3井油气显示好于其它各井,可望在英买3井南部高点地区获得新的油气显示。  相似文献   

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