Distribution And Evaluation Of Hydrocarbon Source Rocks In The Southwest Margin Of Erdos Basin

Erdos Basin in southwestern margin of distribution of magmatic rocks are basicallythe Indo-Yanshan period igneous rock, a large area of distribution of these areas of theigneous rocks are to some extent have influence on the formation of Erdos basin margin ofhydrocarbon source rock distribution and hydrocarbon in southwest china. However, theimpact was positive or negative, is not very clear, so the study of source rocks, types,distribution characteristics and hydrocarbon generation evaluation, has the very vitalsignificance to the oil and gas exploration in the area of strategic deployment.This paper makes full use of outcrop data, geophysical interpretation data, drilling dataand experimental analysis of test data, the organic geochemical analysis, makes acomprehensive study on the hydrocarbon source rock in southwest margin of Erdos basin.Erdos basin developed five sets of potential hydrocarbon source rocks, namely Jixian Countyline containing algae dolomite hydrocarbon source, Ordovician of lower Palaeozoic MarineHydrocarbon source rocks, the upper Paleozoic coal-related rocks, Mesozoic TriassicYanchang7carbonaceous mudstone source rocks and Jurassic Yanan Formation coal measuresource rock. However, by the tectonic uplift and erosion and deposition change effect, type ofhydrocarbon source rock in the region of diversity, poor quality. Jixian County Department ofalgal dolomite, stable distribution, dominated by algae and other lower aquatic organisms,organic carbon content is low (average0.18%), hydrocarbon generation evaluation for thepoor-non hydrocarbon source rock. The Ordovician Marine Hydrocarbon source rocksincluding Majiagou plaster dolomite mudstone and Pingliang, the two type of organic matter,but the Majiagou plaster dolomite low abundance of organic matter (TOC to0.05%-0.15%),middle-poor evaluation of hydrocarbon source rocks of Pingliang formation mudstone, highabundance of organic matter (TOC0.2-0.4%), but mainly distributed in the outcrop area.