黄河北地区晚古生代岩相古地理与煤系烃源岩发育

Paleozoic Lithofacies,Paleogeography and Coal Measures Source Rock Development in Huanghebei Region

黄河北地区广泛发育各种沉积体系,通过对其沉积特征及沉积模式的分析发现黄河北地区晚古生代石炭-二叠纪海相、陆相和过渡相环境均有发育。该地区存在的主要沉积体系类型是潮坪沉积体系、障壁-潟湖沉积体系、河控浅水三角洲沉积体系和河流-湖泊沉积体系。研究发现:本区石炭-二叠系储层烃源岩发育有意义的三个沉积演化阶段分别是本溪期、太原期、山西期;黄河北地区属鲁西地区一部分,晚古生代石炭-二叠系含煤地层主要发育砂岩、泥质岩、碳酸盐岩、岩浆岩和可燃性有机岩(煤),是重要的烃源岩;黄河北煤田含煤地层含煤14层,其中1~5层煤赋存于山西组,6~14层煤赋存于太原组,就可采煤层的层数来说,存在“东多西少”的特点;在含煤地层剖面上的分布特点是“上薄下厚”,主要富煤带则主要分布在东部地区;泥页岩主要发育在石炭-二叠系太原组和山西组,泥页岩层厚度在横向上有一定的规律性,由北向南泥页岩层厚度有逐渐减小的趋势,南部济西矿区和长清矿区,西北部伦镇矿区、李屯矿区厚度发育较好,多在90m以上。

Various sedimentary systems have been widely developed in the Huanghebei region.Through analysis of sedimentary features,sedimentary modes have found that the late Paleozoic Permo-Carboniferous environmental marine facies,continental facies and transition facies all have been developed.Main sedimentary system types in the region have tidal flat,barrier-lagoon,fluvial dominated shallow water delta and fluvial-lacustrine sedimentary systems.The study has found that three significant Permo-Carboniferous reservoir source rock development sedimental evolutionary stages have Benxi Age,Taiyuan Age and Shanxi Age respectively.Huanghebei region is in western Shandong area,late Paleozoic Permo-Carboniferous coal-bearing strata have mainly developed sandstone,argillaceous rock,carbonate rock,magmatic rock and combustible organic rock(coal)are significant source rocks.The coal-bearing strata in Huanghebei coalfield have 14 coal seams,in which,coal Nos.1 to 5 are hosted in Shanxi Formation,coal Nos.6 to 14 in Taiyuan Formation.In the terms of mineable coal numbers have presented“more in east and less in west”features,while in terms of coal-bearing strata sectional distribution features presented“thinner upper and thicker lower”features.Main coal-rich zone has mainly developed in eastern part.Argillutite has mainly developed in Permo-Carboniferous Taiyuan and Shanxi formations;its thickness has certain regular pattern laterally,from north to south have a gradually reduced trend;the Jixi and Changqing mine areas in south,Lunzhen and Litun mine areas in northwest,argillutite developed better,mostly above 90m.