论文部分内容阅读
中国古代海相钾盐找矿是一个“久攻不破”的难题,古代海相及海陆交互相盆地能否成钾也是长期争议的问题,也就是中国小陆块能否成钾、成大钾矿的关键问题。为此,本文以板块构造运动为主线,对中国主要小陆块漂移历史、成盆构造、古气候、古地理及海相/海陆交互相蒸发岩沉积特征进行了系统梳理和总结;在此基础上,基于盆地“构造-物源-气候”三要素耦合成钾理论,分析中国小陆块海相盆地成钾条件、成矿机理;同时,总结和借鉴全球海相钾盐成矿标志,建立钾盐成矿评价指标体系。基于这些研究基础,借助对主要陆块的区域构造和古地理特征、物质来源、古气候面貌等恢复及分析,对主要陆块的海相成钾潜力进行评价,同时预测找钾战略靶区。钾盐成矿模式研究表明:兰坪—思茅盆地白垩系、上扬子陆块四川盆地中—下三叠统、华北陆块陕北盆地中奥陶统及塔里木陆块库车盆地古近系等盆地及其层位具有较大的成钾潜力。结合成钾指标对比分析,优选圈定了思茅盆地南部、四川盆地中东部及塔里木的库车盆地等战略靶区内较为明确的重点靶区,可以进一步开展钻探验证。这些研究成果为在中国继续开展海相钾盐成矿研究和找钾提供科学依据。
Potassium prospecting in the ancient Chinese marine sea is a difficult issue that “long-term attack does not break”. Whether the ancient sea facies and the inter-basin interaction between sea and land can become potassium is also a long-standing controversy, that is, whether small Chinese land can become potassium or not Potash key issue. Therefore, based on the tectonic movement of plate tectonics, this paper systematically reviews and summarizes the sedimentary characteristics of the major continental block drift history, basin-forming structure, paleoclimate, palaeogeography and marine / Based on the coupling of the three elements of “structure-provenance-climate” in the basin with the theory of potassium, the paper analyzes the potassium-forming conditions and metallogenic mechanism of the marine continental basin in China. At the same time, it summarizes and draws lessons from the global marine potash mineralization , The establishment of potassium mineralization evaluation index system. Based on these researches, the potentials of potassium-forming potential in the main continental blocks are estimated by means of the regional tectonics and palaeogeographical features, material sources and palaeoclimate appearances of the main land masses. Potash mineralization patterns show that Cretaceous and Upper Yangtze block of the Lanping-Simao Basin, Middle-Lower Triassic of the Sichuan Basin, Middle Ordovician of the North China Block and the Paleogene of the Tarim Basin, and so on. The basin and its horizon have greater potassium potential. According to the comparative analysis of potassium index, it is preferable to further define the drilling target by defining the key target areas within the strategic targets such as the southern Simao Basin, the central and eastern Sichuan Basin and the Kuqa Basin in the Tarim Basin. These research results provide a scientific basis for carrying on marine potash mineralization research and finding potassium in China.