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从古元古代至晚古生代,华北地台西缘经历了坳拉槽、槽后坳和坳陷发育阶段.笔者在大区域地层对比及详细的沉积环境分析基础上,对晚古生代海水进退与聚煤作用关系作了较深入研究.结果表明:晚石炭世晚期至早二叠世早期华北地台西缘主要为潮坪和三角洲沉积发育区,在空间上沉积环境具有东西有别南北分带的特点;西部由潟湖潮坪沉积环境逐渐过渡为河控潟湖三角洲和受潮汐影响的河控滨海三角洲沉积环境;东部为潮坪沉积环境,东侧边缘还出现近山滨海平原沉积环境.研究区在晚石炭世早期一早二叠世早期发生过4次2级海水进退,其中第三、第四次海侵全区发育.早二叠世早期初的第三次2级海侵是最大的一次.最大海侵前夕——晚石炭世晚期末是大区域发育厚—巨厚煤层的最好时期.潟湖三角洲平原和陆源碎屑潮上泥炭坪及泥炭沼泽是最佳的聚煤场所.
From the Paleoproterozoic to the Late Paleozoic, the western margin of the North China platform experienced the developmental stages of the aulao trough, depression and the depression.The author based on the stratigraphic contrast and detailed sedimentary environment analysis, The results show that the sedimentary environment in the north of North China Platform was mainly tidal flat and delta sedimentary development in the late Late Carboniferous and Early Early Permian, The sedimentary environment in the tidal flats of the lagoon gradually transited into the controlled delta in the river controlled lagoon and the river controlled delta in the tidal flat, the tidal flat sedimentary environment in the east and the marginal coastal plain sedimentary environment in the east marginal.The study area was at night In the Early Carboniferous-Early Early Permian, there were 4 Class 2 seawater advance and retreats in the early and Early Cretaceous, with the third and the fourth sea transgressions throughout the region. The third Level 2 transgression in early Early Permian was the largest. On the eve of the transgression-the late Late Carboniferous period was the best period for the development of thick-thick coal seams in the large area.The lagoon deltaic and terrigenous tidal flat tidal flats and peat bogs were the best sites for coal accumulation.