二连盆地隆起带阿其图乌拉凹陷铀成矿环境与远景预测

Uranium mineralization and prediction for the Aqituwula depression in the Eren Basin, Inner Mongolia

关键词:  二连盆地  阿其图乌拉凹陷  赛汉组  铀成矿环境

Key words:  Eren Basin  Aqituwula depression  Saihan Formation  uranium mineralization

摘要:

阿其图乌拉凹陷为二连盆地隆起带上众多的含铀山间盆地之一。本文首次在现有钻探资料的基础上,结合区域地质特征,对阿其图乌拉凹陷赛汉组的铀成矿环境进行了详细分析,并综合铀储层、后生蚀变和铀源等因素对铀成矿前景进行了预测。研究认为,研究区目的层具有来自北部苏尼特隆起的丰富铀源,且铀源近。赛汉组上段和下段均具有完整的利于成矿的"泥-砂-泥"结构,发育大型呈泛连通的辫状砂体,发育潜水-层间氧化带,且控制矿体的产出等。赛汉组上段及下段均具有非常有利的铀成矿环境。远景区处于辫状河三角洲砂带中部的氧化-还原过渡带及灰色残留体上,资源潜力较大。

Abstract:

The Aqituwula depression is one of uranium-bearing intermontane basins in the Sunite uplift zone, Eren Basin, Inner Mongolia. The present paper focuses on the uranium mineralization and prediction for the Saihan Formation in the Aqituwula depression on the basis of regional geology and existing data. The uranium in the study area is believed to be derived from the Sunite uplift zone in the north. Both the upper and lower members of the Saihan Formation are characterized by a complete "mud-sand-mud" architecture favourable for the uranium mineralization, giant and connected braided sandstone bodies and phreatic-interformational oxidation zones which put the uranium ore bodies under control, and thus serve as the favourable environments for the uranium mineralization. The prospect area is located in the oxidation-reduction transitional zones and grey relicts in the central part of the braided deltas and is highly prospective for the uranium exploration.