宁夏宁东煤田积家井矿区延安组含煤地层沉积特征

详细分析了宁夏宁东煤田积家井矿区延安组含煤地层沉积特征:岩性组合、可采煤层、厚度变化、沉积构造、物性特征、含煤系数等。区内延安组含煤地层平均厚度400 m左右,可采煤层或局部可采煤层有9层,平均总厚度为17.44 m,含煤系数4.3%。延安组自下而上可分为5个岩段,其中第Ⅰ段沉积环境以河流相沉积环境为主,含5层煤;第Ⅱ段为湖泊三角洲沉积体系,含6层煤;第Ⅲ和第Ⅳ段为三角洲沉积体系,共含10层煤;第Ⅴ段又演变为河流沉积体系,含2层煤。研究成果为该区煤炭资源勘探开发和综合评价提供参考。

Sedimentary characteristics of coal bearing strata in Yanan Formation of Jijiajing mining area Ningdong coal field

Conducted a detailed analysis of the sedimentary characteristics from followed aspects ： Lithological combi- nation, minable coal seams, thickness variation, sedimentary structure, physical properties, and coal bearing ratio of coal bearing strata in Yanan Formation of Jijiajing mining area, Ningdong coal field, Ningxia Province. The average thickness of Yanan Formation is about 400 m, containing nine mineable or regional mineable coal seams, whose average aggregate thickness is about 17.44 m, and average coal bearing ratio is 4. 3 percent. Yanan Formation can be divided into five sections from bottom to top. The sedimentary environment of the first section is dominated by fluvial facies, containing five coal seams, the second is lake delta sedimentary system, containing six coal seams, the third and fourth sections are delta sedimentary system, totally containing ten coal seams, the fifth section changes into fluvial facies again, containing 2 coal seams. The research would provide references for the exploration, development as well as overall evaluation of coal resources in this area.