断裂带地球化学深穿透理论与方法在钾盐找矿中的应用

文中介绍了断裂带地球化学深穿透理论与技术方法,并结合钾盐找矿实践,对相关技术方法的应用进行了探讨。断裂带地球化学深穿透技术包括地表测线、稀有气体同位素示踪和钾盐深度预测模型,笔者的主要思路是通过地表元素异常来捕捉可能来自深部的物源信息,预测大概的找钾靶区和深度,降低找矿成本。沿垂直于构造断裂带的方向采集地表沉积物、水样,分析其化学元素含量或比值,可以有效识别地球化学异常点;通过分析沿断裂带上升的卤水中逸出的稀有气体(氦、氩、氖等)同位素组成,可以判别气体的来源和断裂的深度,从而辅助判别卤水来源和深度;通过文章给出的一系列地球化学指标和方法,可以识别异常、综合判别卤水或盐类物质来源和深度,灰色模型和异常判别程序的编制可以大大缩短运算和判别时间。上述方法在实际工作中取得了较好的效果,在今后研究和实践中可以进一步提高和完善。

Fault belt geochemical deep-penetration theories and techniques for potassium prospecting

Fault belt geochemical deep-penetration theories and techniques are introduced in this paper, with emphatically placed on techniques on potassium prospecting based on practical work. Fault belt geochemical deep-penetration techniques, such as survey lines, isotope tracer technique and potash deposit prediction model, are shown in detail, with the central idea that deep information on material sources can be captured through surficial geochemical anomalies so as to locate potential potassium deposits at obviously lower prospecting costs. Surface sediments and water (brines or saline springs) samples in the direction perpendicular to the fault belts are collected and analyzed, so that geochemical anomaly points can be effectively identified according to differences between element content or content ratios of these samples. Isotopic compositions of noble gases (He,Ar,Ne,etc.) escaping from brine rising along fault zones are of great importance in distinguishing the sources of the gases and the depths of the fractures as well as in estimating the sources and depths of brines. Geochemical anomalies can be identified and depths and sources of salts or brines can be predicted according to a given series of geochemical indicators and methods. In addition, the gray model and anomaly indentification programs can greatly shorten the computing and discriminating time. These techniques show good performances in practical work but need improvements in further studies.