鄂尔多斯盆地北部上古生界天然气成藏期次——以杭锦旗探区为例

杭锦旗探区是中国石油化工股份有限公司在鄂尔多斯盆地北部的一个重点区块，油气生、储、盖条件良好，目前对于该区上古生界天然气成藏期次的认识存在分歧。通过生烃时间法、圈闭形成期法、流体包裹体法以及储层致密化时间和煤热解模拟结果等方法对该区上古生界油气成藏期次展开研究。结论认为杭锦旗探区上古生界存在2期大规模油气运聚；结合生烃高峰和流体包裹体均一化温度结果，明确了该区上古生界油气成藏时间，分别对应于中-晚侏罗世和早白垩世末-至今，前者为油气兼生期，后者为大规模天然气生成期。研究过程中结合多种方法和手段来判识油气成藏期次，避免了单一方法的局限性，结论及认识的可信度更高。

The timing of gas pooling in the Upper Paleozoic in the northern Ordos Basin: A case study of the Hangjinqi Block

The Hangjinqi Block, one of Sinopec's major exploratory blocks in the northern Ordos Basin, is favorable for its source rocks, reservoirs and sealing conditions. At present, there is still much controversy over the timing of hydrocarbon pooling in the Upper Paleozoic in the study area. So various methods, such as hydrocarbon generation time, trap forming stage, fluid inclusions, reservoir tightening time and coal pyrolysis simulation, are used to study the timing of hydrocarbon pooling. The study shows that there are two periods of large-scale hydrocarbon migration and accumulation in the Upper Paleozoic in the Hangjinqi Block. And the analysis of peak hydrocarbon generation and homogeneous temperatures of fluid inclusions reveals that these two periods correspond to a stage of co-generation of oil and gas from Middle to Late Jurassic and a stage of large-scale gas generation from late of the Early Cretaceous till present respectively. The application of multiple methods overcomes the limits and shortcomings of a single one, thus improving the reliability of the conclusions.