南祁连西段清水沟南巴龙贡噶尔组地层特征及时代讨论  

DISCUSSING THE STRATIGRAPHIC CHARACTERISTICS AND ITS TIME OF BALONGGONGGA′ER FORMATION IN QINGSHUIGOU OF THE WESTERN OF SOUTH QILIAN

作　　者：张国英[1] 丁书宏 

机构地区：[1]甘肃省地质调查院,甘肃兰州730000 [2]甘肃省地矿局第四地勘院,甘肃酒泉735000

出　　处：《甘肃地质学报》2004年第1期38-45,37,共9页Acta Geologica Gansu

摘　　要：在南祁连西段清水沟南广泛分布着一套深色碎屑沉积岩系,经区域对比划归为巴龙贡噶尔组,其时代定为早志留世。该组岩石由细砂岩类—粉砂岩类—泥岩类(已变质成千枚岩岩类)组成,砂岩层中见有粒序层理、交错层理,发育水平纹理。细砂岩、粉砂岩中杂基含量高达25%～45%,指示浊流沉积特点,岩石中发育不完整的鲍马层序。该组岩石沉积构造、基本层序、粒度曲线、微量元素、稀土元素特征都反映出该组形成于海底扇区,浊积岩与深海泥岩以不同比例随机重复组合构成复理石沉积建造。In the western of South Qilian, southern of Qingshuigou, a clasitic sedimentary rock series, dark colour, widespread there, through regional correlation, which be delermined into Early Silurian Epoch and composed of fine sandstone, siltstone and argillite (phylite). Graded bedding, cross bedding and horizontal lamination occurred in sandstone. Foreign matter content up to 25%～45% in fine sandstone and siltstone, and it showed its turbidity deposit characteristics and in which Bouma sequence developed uncompletely. In this Formation, the lithology, sedimentary structure, sequence, grain size curve, microelements and REE, all of their characteristics showed that it formed in submarine fan area. The turbidite and deep-sea argillite at various rate formed flysch Formation.

关 键 词：祁连山西段 巴龙贡噶尔组 地层特征 时代讨论 

分 类 号：P53443[天文地球—古生物学与地层学]