贵州省织金—纳雍煤田构造特征及其成因

织金—纳雍煤田主要发育NE、NW、EW及近SN向四组褶皱与断裂,其中以NE向最为发育。在早燕山期近EW向最大主应力作用下,黔中隆起及其邻区发生剧烈造山运动,在煤田东部边界形成向西逆冲的区域性大断裂—遵义断裂,并伴生一系列近NS向褶皱及断层。自东向西的强烈挤压使得垭都—紫云断裂带发生压剪性活动,在西部边界靠近断裂带形成一系列NW向褶皱及断层。随后主应力转变为SE—NW向,受到隆起的阻隔及纳雍—瓮安断裂、垭都—紫云断裂的限制,在煤田中部形成NE向褶皱及断层,此时奠定了织纳煤田的基本构造格局。晚燕山期将早期NE向构造左行剪切成"S"形,晚燕山期及喜马拉雅期主要表现为对早期构造的继承性发展。

Structural Features and Their Genesis in Zhijin-Nayong Coalfield, Guizhou Province

Four direction sets of NE, NW, EW and near NS folds and faults are developed in the Zhijin-Nayong coalfield, of which the NE set is most developed. Under the early Yanshanian EW maximum principal stress, intensive orogenic movement happened in the Qianzhong uplift and its contiguous area, a mega fault, the Zunyi fault was formed at the east border of the coalfield and thrusting westward, associated with a series of near NS folds and faults. The strong compression from east to west made compresso-shearing activities happened in the Yadu-Ziyun faulted zone, a series of NW folds and faults were formed at the western border near the faulted zone. Subsequently, the principal stress had turned into SE-NW direction, it was obstructed by the uplift and confined by Nayong-Wengan and Yadu-Ziyun faults, NE direction folds and faults were formed in the middle part of the coalfield, thus the basic tectonic framework of Zhijin-Nayong coalfield settled. During late Yanshanian stage, the early stage NE structures were sinistrally sheared into ＂S＂ shaped, late Yanshanian and Himalayan tectonic movements have showed inherited development of early stage structures.