Distribution Pattern Of Geochemical Elements Based On Sparse Principal Component Analysis

With the discovery of outcrop mine and shallow mine,buried ore and deep mine have become the main ore prospecting objects.There are about 1.2 million km~2shallow overlay area with an cover thickness of less than 50m in China,mainly distributed at the edge of the mountain,intermontane basin and both sides of the river valley,these areas are often tectonic active lots,containing abundant mineral resources.The research area,Jining,is a grassland overlay area,located in the molybdenum ore belt of the northern margin of North China Craton,,there are polymetallic deposits such as gaint molybdenum ore,lead-zinc ore and silver-lead-zinc ore in the area,which are similar in terms of geological background and metallogenic conditions,and are located on the same structural line and belong to the same metallogenic belt.Therefore,this area has netter potential for molybdenum polymetallic prospecting.The study around the shallow overlay area of Fengzhen-Guantunbao,and the research objects in this paper are geochemical data obtained from regional survey geochemical exploration and shallow drilling geochemical exploration.Carring out method and technology experiments,exploring and improving key technical problems,providing certain method and technical support for the comprehensive development of geological prospecting in shallow overlay areas.The principal component analysis in a kind of popular data dimension reduction statistical method,but it ist results are difficult to interpret when calculating the multiple variables.The sparse principal component algorithm has the feature of overcoming the difficulty of interpreting the correspondence of each principal component by the traditional PCA,which is a dimensionality reduction algorithm that sparses the principal component score number,that is,the partial elements of the load vector to zero.This paper will use the sparse principal component analysis algorithm to process the shallow drilling data in the area and 1:50,000 exploration geochemical data,and extract the favorable information for mineral exploration from it.This research will sparse the shallow drilling data from vertical and horizontal aspects,and analyze the element combination distribution rules combing with sparse results of exploration data,through studying the elemental combination rules of these superficial layers and shallow overlay layers,gradually analyze and speculate the issues such as the element combination rule and element migration rule in the deep underground layers,mainlt get the following knowledge:(1)Based on shallow drilling geochemical data analysis,analysis of data from different depths,the combination of elements remains substantially unchanged mineralization,and look at the entire area of shallow drilling,high temperature combined mineralized elements SPCA1 W-Mo-Bi from light to deep is widespread,and the W-Mo mineralization anomaly is obvious at 20 meters.The analysis of geochemical data of different particle sizes shows that the mineralization element combinations in SPCA1 are different,indicating the different particle size adhesion to the elements.With certain influence,the combination of mineralization elements in the particle size of-20~120 mesh is more complete,and the variation trend of SPCA1 and SPCA2 in different depths is basically consistent.Combining the results of vertical geochemical data,it can be concluded that the combination of medium-low temperature mineralization elements is spatially associated with metamorphic rocks such as shallow granules and gneiss.(2)In the survey geochemical data,the SPCA1 mineralization element combination content score enrichment area overlaps with the existing lead-zinc deposit area near the study area,indicating that SPCA1 can well indicate the existing lead-zinc deposit,and SPCA1.The SPCA2 enrichment area overlaps with the metamorphic rock strata areas such as shallow granulite and gneiss in the study area.SPCA2 can be used to indicate metamorphic rocks well;the high value area of SPCA3 and the spring gullies found in the area The molybdenum polymetallic deposits are stacked together to well define the Mo anomaly area.Combining the results of prospecting geochemical data,high-temperature mineralization element combination W-Mo-Bi which is closely related to the medium-acid igneous rock in space.