The Sedimentary Tectonics And Shale Gas Exploration Prospects Of The Main Dark Shale Formations In Jiangsu And Its Neighbouring Area

In recent years,the successful exploration of shale gas in the upper Yangtze region has been a good experience for shale gas exploration in lower Yangtze region.Jiangsu and its neighbouring area have plenty of rich organic mud shale and the basic research here is unsystematic.In this paper,it chooses more sets that are rich in organic matter as the main target of the shale formation in Jiangsu and its neighbouring area since Paleozoic.Through the collection of field and drilling data,it carries out the research on geology structure,sedimentary distribution and lithofacies of these shale.In this way,it provides technical support for the research area of shale gas resource survey and constituency evaluation.The main results and conclusions are as follows:Early Cambrian tectono-sedimentary pattern mainly shows the tectonic features of the"two-graben and two-horst" distribution in the field.There are three mud shale depositional centers,namely,Jingxian county,Huangshan and Jixi area and Nanjing Mufu mountain area,and there is also a conjectural xuancheng suzhou area depositional center.The study area was a typical foreland basin during the early Silurian period.There are four relatively isolated mud shale depositional centers,namely Anqing,Taiping,Tongling and Jurong area.There are two large delta deposits developed in the Permian Longtan formation.Respectively,the northern delta and the southern delta.There are several depositional centers,including Suzhou,Wuxi Jiangyin,Changzhou Jintan and Changxing area of Taihu deposit center.There is another depositional center,the Xuanjing area.In the field,there was a layer of tuff in the Gaojiabian Formation,and the accurate age was(442.8 + 2.6)Ma by the zircon LA-ICP-MS,which made the Gaojiabian Formation got the accurate age for the first time.