Reconstruction Of The Paleozoic To Mesozoic Basin Prototype In Kongquehe Area Of Tarim Basin

Kongquehe region is a typical superimposed area in northeast Tarim basin. It has undergone multistage tectonic movements and has superimposed many prototype basins. Different types of prototype basin have the important influence and the control action to various times factors of hydrocarbon accumulation. Therefore, the prototype basin research has the important meaning to oil and gas industry in Kongquehe region northeast of Tarim basin.This article takes the basin-mountain theory as the instruction and takes Paleozoic Era - Mesozoic Era prototype basin in the Kongque River area as the object. In the basic of regional geology structure background research, this article mainly resumed and rebuilded the prototype basin and the sedimentary facies of the Ordovician, Silurian Period and Jurassic and analyzed the control action of prototype basin in different time to hydrocarbon accumulation elements , through the open country observation, research of the well drilling core sample, log information reorganization, seismic stratigraphy application, constant and trace element distinction, heavy mineral analysis and so on many kinds of research tools.According to Kongquehe area sedimentary facies characteristic research and combining with the evidences such as REE, constant and trace element , characteristic of heavy mineral and the ancient flow direction which observes in outcrops and so on, the paper makes the synthetic study of the prototype basin. Through the research, it indicates that the area is in extensional environment in the Ordovician time, basin boundary lies along the east yamaguchi or further, inner area takes xingdi fault for boundary, the majority areas of the north part is shelf margin slope to open continental shelf deposition , the south part is deep sea basin deposition and developed a suit of flysch formation, basin prototype is continental rift basin; In Silurian kuruktag and kongquehe slope occurred tectonic inversion in the extrusion background , kuruktag area had been overall uplifted, the range of the basin reduced , mainly is littoral neritic facies , the type of basin is continental marginal depression basin; In Jurassic and the Cretaceous period, stratum deposition presented intracontinental depression basin characteristic , in early Jurassic sedimentary bound is relative small, only in the south part of kongquehe slope, it began to appear lacustrine deposits, to middle Jurassic, the acreage of lacustrine deposits gradually enlarged and achieved the largest till the late of middle Jurassic, kuluktag mountain is likely to be low uplift, kongquehe area developed floodplain- shallow lake-deep lake deposits from north to south , basin type is intracontinental depression basin.Based on the research of evolution characteristics of hydrocarbon source rocks on the study area ,and the analysis results and materials of heavy minerals, REE, ancient flows in Kuruktag outcrop area and some drilling samples, the source area in Kongquehe area are revealed :Ordovician- mainly from north-east; Silurian-mainly from the South Tianshan ancient land in the north; Jurassic- Kuruktag uplift area which is also the source area of Yanqi Basin in the north and kongquehe slope area in both north and south.At the same time, the research of reef flat facies on the study area is carried out, some progress about the formation, distribution of reef has been made, which has important guiding role in the oil and gas exploration in Kongquehe areas. Because of the complex multi-phase tectonic activities, Kongquehe area has experienced a number of prototype basin evolution, different types of prototype basin has an important role in the control of trap formation, hydrocarbon source rocks, reservoir cap, and hydrocarbon-generating and accumulating history. After the comprehensive study of prototype basin and these elements, this paper points out Palaeozoic -Mesozoic Longkou anticline structural zones , Mesozoic Weima-Kaiping tectonic belt, Paleozoic eastern slope in Caohu depression and coonen edge slope facies are advantageous exploration zones.