Analysis And Reconstruction Of The Carboniferous Basin In Eastern Qaidam Basin

Qaidam basin's eastern region(hereinafter referred to as Chai Dong area)is a hotpot to study the evolution of structure of mainland China.Especially in the Tethys Ocean tectonic research topic and the Qinghai-Tibet plateau uplift research topic.With the deepening of the exploration process in Chai Dong areas over the years,we found that besides the Jurassic formation,Chai Dong area carboniferous strata are also potential a very good formation of hydrocarbon generation.There are three problems in the restoration of the carboniferous archetypal basin in Chai Dong area:(1)The understanding of geotectonic evolution in the Chai Dong area is still not clear enough;(2)There is still a controversy about the determination of paleo geotectonic environment in carboniferous period;(3)The study on the carboniferous system structure reconstruction in the Chai Dong area needs to be further researched.Especially The influence on the structural deformation of carboniferous system(including the formation of traps)and on the formation denudation are analyzed.In this paper,through field outcrop observation combined with previous data,the stages of geotectonic evolution of the corresponding unconformity in Chai Dong area are analyzed deeply.After the sedimentary lithologic facies characteristics of Chai Dong area were obtained,the associated data on the associated geochemistry were used to re-judge and understand the tectonic environment in the carboniferous period.Based on the analysis of the basin deformation characteristics and structural styles and the basin types of different regions in the Chai Dong area in the carboniferous period,we used balanced section technology and prototype basin recovery technology to deduce and analyze the original shape of the carboniferous basin in the Chai Dong area.Combined with the characteristics of geotectonic evolution in different geological periods after carboniferous period and the response results in Chai Dong area,the retro gradation of the basin is analyzed and the strain degree of each period is calculated quantitatively.