竹山幅区域化探数据因子计量地球化学图的编制与效果

本文用R型因子分析方法,处理1:200000竹山幅区域化探(1911件样品,28种元素定量分析)数据,编制了斜参因子计量地球化学图、因子剩余异常图及综合异常图,构成一套综合性指标的地球化学图件。这套图件在解决本区(变质岩)地层划分、岩浆岩圈定、构造预测等基础地质问题是有效的,对区内银金多金属矿产也有一定反映;提出了震旦系郧西群应归属元古界武当群的新认识,已为地质工作者接受。从地球化学数据的地质解译出发,因子地球化学图是地球化学信息的地质推断图,还可使复杂地球化学区的多种地质—地球化学因素得到分解和解释:与单元素地球化学制图相比,能直接获得地球化学的解释信息和清晰的图象显示,使单元素地球化学图解释中的困难以及综合异常图图面负担过重的问题得到一定的解决。因子地球化学图件可作为单元素地球化学制图的一种辅助形式,它有助于区域化探资料的解释与推断。

COMPILATION OF THE FACTOR SCORE MAP OF THEZHUSHAN MAP AREA WITH REGIONAL GEOCHEMICALDATA AND ITS RESULT

Quantitative analytic data of 28 elements in₁₉₁₁ regional geochemical samplesfrom the 1:200,000 Zhushan map area were processed by means of R-type fa-ctor analysis, and, on such a basis, oblique reference factor score geochemicalmap, factor residual anomaly map and integrated anomaly map were com-piled, which make up a geochemical map-compiling series characterized byintegrated indexes. Acomparision with the geological information shows thatthis set of maps is helpful in solving some basic goological problems of thisarea such as the division of metamorphic strata, delineation of magmaticbodies and inference of structures; it also indicates to some extent Ag-Au poly-metallic resources within the area; with these maps, a new suggestion was putforwaxd that the Sinian Yingxi Group should be incorporated into the Protero-zoic Wudang Group, which has been favourably accepted by geological workers.