松辽盆地南部泉头组砂岩型铀矿成矿条件分析

Metallogenic Condition Analysis of the Sandstone Uranium Deposit in Quantou Formation,Southern Songliao Basin

通过对松辽盆地南部泉头组砂岩型铀成矿条件分析认为:泉头组半干旱的亚热带古气候对成矿有利。河流相和三角洲相沉积具有形成厚大砂体的条件。砂体较为发育,单层砂体厚度可达42 m。虽砂体中有机质含量较低,但泉头组下部含煤层中的烃类可通过断裂构造及不整合面上升进入砂体,弥补还原剂的不足。工业铀矿孔的发现反映出泉头组有铀的大规模富集。总之,泉头组是松辽盆地南部一个重要的找矿目的层,找矿意义重大。

Based on an analysis of the metallogenic conditions of the sandstone type uranium deposit in Quantou Formation within southern Songliao Basin,this paper holds that semi-arid subtropical paleo-climate was favorable for uranium mineralization.Fluvial and deltaic sediments provided space for the development of thick and large sand bodies.These sand bodies are well developed in Quantou Formation,with the monolayer of the sand body reaching over 40 meters in thickness.Though organic carbon content was low in sand bodies,hydrocarbon in coal-bearing layers under Quantou Formation probably migrated upwards into sand bodies along faults and sur-faces of the unconformity and increased the capability of the reducing agent.The discovery of industrial uranium ore bodies suggests large-scale uranium enrichment.Therefore,the Quantou Formation may be regarded as an important target layer for sandstone type uranium exploration.