论文部分内容阅读
鄂尔多斯盆地从三叠纪至现今上古生界气源岩具有持续的供气能力，早日垩世后上古生界气源岩仍然具有可观的排气量。上古生界气源岩持续的供气能力、巨大的排气量是上古生界天然气富集成藏的有利条件，表明鄂尔多斯盆地具有形成深盆气的物质基础。鄂尔多斯盆地上古生界天然气三叠纪-早白垩世向北大规模运移，早白垩世后天然气主要是就近运移聚集，为盆地大面积含气创造了有利的气源条件。下石盒子组-山西组分流河道和河口砂坝砂体物性最好，分布于4个大型河流-三角洲沉积体系中。这些沉积体系中的河道砂体是天然气富集的有利场所。稳定的构造背景和区域盖层、直接盖层良好的封盖能力构成了上古生界天然气保存的有利条件。鄂尔多斯盆地上古生界天然气成藏的最关键条件是有利砂体的分布。加强石盒子组-山西组砂岩储层的分布预测对上古生界天然气的勘探有着重要意义
The Ordos Basin gas source rocks from the Triassic to the present Upper Paleozoic have a continuous gas supply capacity, and the Upper Paleozoic gas source rocks still have considerable displacement after the Early Cretaceous. The continuous supply of gas from the Upper Paleozoic and the huge displacement of the upper Paleozoic gas are favorable conditions for enrichment and accumulation of natural gas in the Upper Paleozoic, indicating that the Ordos Basin has the material basis for the formation of deep basin gas. The Upper Paleozoic natural gas in the Ordos Basin migrated to the north from the Triassic to the Early Cretaceous. After the Early Cretaceous, natural gas mainly migrated and accumulated nearby, creating favorable gas source conditions for large area gas in the basin. Lower Shihezi Formation - Shanxi Component flow channels and estuarine sandstones have the best physical properties and are distributed in four large river-delta sedimentary systems. Channel sand bodies in these sedimentary systems are favorable sites for natural gas enrichment. The stable tectonic setting and regional cover, and the good sealing ability of direct cover, constitute favorable conditions for the preservation of natural gas in the Upper Paleozoic. The most important condition for gas accumulation in the Upper Paleozoic in the Ordos Basin is the distribution of favorable sand bodies. Strengthening the Shixianzi Formation - The prediction of the distribution of sandstone reservoirs in Shanxi Formation is of great significance to the exploration of natural gas in the Upper Paleozoic