准噶尔盆地车排子地区铀控矿因素分析——以沙湾组一段3砂组为例  

Analysis on Uranium Mineralization Controlling Factors of the Third Sand Layer in the First Member of Shawan Formation in Chepaizi Area,Junggar Basin

作　　者：阿种明[1] 伏多旺 王国荣[1] 杜默[1] A Zhongming;FU Duowang;WANG Guorong;DU Mo(Geologic Party No.216,CNNC,Urumqi,Xinjiang 830011,China)

机构地区：[1]核工业二一六大队,新疆乌鲁木齐830011

出　　处：《铀矿地质》2023年第1期46-58,共13页Uranium Geology

基　　金：中国核工业地质局铀矿地质项目“新疆准噶尔盆地砂岩型铀矿综合编图与选区”(编号:202206-8资助)。

摘　　要：车排子地区位于准噶尔盆地西缘,其中-新生界已发现有砂岩型铀矿,前人针对该地区铀成矿前景及找矿方向进行了一定的论述,但铀控矿因素尚不明朗。文章通过车排子地区铀矿勘查钻孔、部分石油钻孔柱状图、柱状对比图以及天然伽马值等资料,以沙湾组一段3砂组为例,对砂岩型铀控矿因素进行了分析。认为车排子地区中-新生代地层呈向南倾的缓坡,新地层多超覆在老地层之上,对后期含氧含铀水广泛入渗较不利;逆时针旋转构造作用使沙湾组尖灭带呈北东走向,东北部埋深浅处为现今地下水补给区,西南部埋深深处为现今地下水局部排泄源;沙湾组一段3砂组西北部发育来自北部方向扎伊尔山的“近源”扇三角洲砂体,南部和中东部发育来自西南方向“远源”辫状河三角洲砂体。在研究区中北部,双物源砂体叠置连通,“近源”砂体中自北西向南东发育的氧化带延入“远源”辫状河砂体,在其前锋线附近形成和发育放射性异常或铀矿化,具有较好的砂岩型铀成矿找矿前景。Sandstone type uranium deposits have been discovered in the Middle Cenozoic in Chepaizi area,western margin of Junggar Basin. The uranium metallogenic prospect and prospecting direction have been discussed by some research, but the ore-controlling factors was not clarified. In this paper, the ore-controlling factors were studied with the data of gamma logging and stratigraphy of uranium and oil-gas exploration. It was considered that the Mesozoic and Cenozoic strata were in gentle slope dipping southward. The counterclockwise rotation structural action made the Shawan Formation pinching out in NE trending, the shallow part of the northeast is the groundwater recharge area, and the deep southwest part is the local discharge source of groundwater. In Chepaizi area, the“near-source” fan delta sand body was developed in the third sand layer of the first member of Shawan Formation in the northwest, “far-source” braided river delta sand bodies were developed in the south and middle-east, and the double-source sand bodies were superimposed and connected to form the oxidation zone from NW“near-source”sand bodies to the SE“farsource”sand bodies in the central and northern part of the study area. Therefore, the uranium anomalies and mineralization maybe fostered in the front of the oxidation zone in the central and northern part of Chepaizi area.

关 键 词：铀成矿 控矿因素 沙湾组一段 车排子地区 

分 类 号：P619.14[天文地球—矿床学]