甘肃阿干煤田一带中生界沉积构造演化及找煤前景  

MESOZOIC SEDIMENTARY TECTONIC EVOLUTION AND THE PROSPECT FOR COAL EXPLORATION IN AGAN COALFIELD AREA GANSU PROVINCE

作　　者：韩少甲 曹小勤 王兴太 HAN Shao-jia;CAO Xiao-qin;WANG Xing-tai(Gansu Institute of Coal Geology,Lanzhou 730000,China)

机构地区：[1]甘肃煤田地质研究所,甘肃兰州730000

出　　处：《甘肃地质》2022年第4期24-31,共8页Gansu Geology

基　　金：甘肃省地质勘查基金项目“甘肃省阿干煤田外围煤炭资源普查(201601-M01)”资助。

摘　　要：本文通过收集研究甘肃省阿干煤田及周边以往钻孔资料,梳理了阿干煤田及周边构造单元中生代地层分布特点,还原了阿干煤田一带自中生代以来构造及沉积环境的演变过程,一是印支运动末期至燕山运动早期盆地沉降充填阶段,主要控制侏罗系地层沉积,中侏罗统含煤地层主要分布在兴隆山隆起区及周边的阿干煤田、水岔沟煤田、高家湾—羊寨坳陷等地区;二是燕山运动中晚期兴隆山隆起抬升阶段,主要控制白垩系地层沉积,主要分布在阿干煤田以西的广大地区。通过恢复侏罗系地层原始沉积范围及后期改造过程,确定了中侏罗统含煤地层赋存的有利区在阿干煤田、水岔沟煤田及高家湾—羊寨坳陷内,这些区域均为兴隆山隆起抬升剥蚀后中侏罗统含煤地层残留区。其中阿干煤田、水岔沟煤田已证实有可采煤层赋存,高家湾—羊寨坳陷面积是阿干煤田的近两倍,与阿干煤田、水岔沟煤田为同一套沉积体系,具备良好的找煤潜力。In this paper, the distribution characteristics of Mesozoic strata in Argan coalfield and its surrounding tectonic units are sorted out by collecting the data of previous boreholes. And the evolution process of tectonic and sedimentary environment since the Mesozoic era is restored. The evolution of tectonic and sedimentary environment in Agan coalfield since Mesozoic can be divided into two stages. One is the stage of basin subsidence and filling from late Indosinian to early Yanshanian, which mainly controlled Jurassic formation deposition. The Middle Jurassic coal-bearing strata are mainly distributed in the present Xinglongshan uplift area and the surrounding areas such as Agan coalfield, Shuichagou coalfield, Gaojiawan Yangzhai depression. The second is the uplifting stage of Xinglong Mountain in the middle and late Yanshan period,which mainly controlled the cretaceous stratigraphic deposition. The Cretaceous strata are mainly distributed in the west of Agan coalfield.Through the restoration of the original sedimentary range of Jurassic strata and the later reconstruction process, it is determined that the favorable areas for the occurrence of coal bearing strata are located in Agan coalfield,Shuichagou coalfield and Gaojiawan Yangzhai Depression. These areas above are all residual areas of Middle Jurassic coal-bearing strata after Xinglongshan uplift. Gaojiawan Yangzhai depression is nearly twice the area of Agan coalfield, and it is the same depositional system with Agan coalfield and Shuichagou coalfield, so it has a good potential for coal exploration.

关 键 词：中生界 沉积构造演化 聚煤规律 阿干煤田 兰州—民和盆地 甘肃 

分 类 号：P618[天文地球—矿床学]