广东北市地区1∶5万水系沉积物测量粒级试验  

A study on 1 ∶50 000 stream sediments survey in Beishi area,Guangdong Province

作　　者：李冲 郝志红[2] 张忠进 LI Chong;HAO Zhi-Hong;ZHANG Zhong-Jin(Foshan Institute of Geological Survey,Foshan 528000,China;Institute of Geophysical and Geochemical Exploration,CAGS,Langfang 065000,China)

机构地区：[1]广东省佛山地质局,广东佛山528000 [2]中国地质科学院地球物理地球化学勘查研究所,河北廊坊065000

出　　处：《物探与化探》2018年第2期303-311,共9页Geophysical and Geochemical Exploration

基　　金：中国地质调查局地质大调查项目(12120113063700);中央级公益性科研院所基本科研业务费专项(YYWF201514;AS2013J11)

摘　　要：在广东北市地区选择310 km2试验区开展1∶5万水系沉积物测量粒级试验。在同一采样点位分别采集-10^+80目和-60目两种粒级的样品,进行多元素含量测试,从水系沉积物粒级分布特征、元素含量分布特征、富集倾向性和地球化学特征4方面对上述两种粒级试验效果进行综合评价。结果表明:(1)水系沉积物中-10^+80目粒级段样品占全部样品的86.59%,质量上占有绝对优势;(2)除W、Sn、Pb外,试验区多数元素在两种粒级总体上具有相似的含量分布特征,且在高背景区或矿(化)区均不同程度富集于-10^+80目粗粒级,在低背景区或非矿(化)区则正好相反;(3)包括Au、Ag、Zn、Mo、Sb在内,多数元素-10^+80目粗粒级显示的区域地球化学分布与区域地质吻合度更高,地球化学分布界线与地质界线更为接近;(4)多数元素-10^+80目粗粒级显示的地球化学高背景-正异常区的规模和强度整体上大于-60目细粒级,Mo、Sb等尤为明显。因此,广东北市地区1∶5万水系沉积物的最佳采样粒级为-10^+80目。A study on mesh experiment of stream sediments survey at a scale of 1:50000 was conducted in a selected area about 310 square kilometers of Guangdong Beishi area.The-1 0^+80 mesh and-6 0 mesh of stream sediments"was collected at the same sampling site for the content analysis of various elements.The effect of mesh was evaluated comprehensively from the distribution characteristics of elements content,the enrichment tendency and the characteristic of geochemical.The result shows th at:1)The weight of the-10^+80 mesh assumes absolute?superiority?in stream sediments.2)Elements in the two grade with similar content distribution characteristics in the mass and enriched in high background or mineralization zone with varying degrees,in low background or non-mineralization zone by contrary,except W、Sn、Pb.3)The regional geochemical distribution of most elements in-1 0^+80 mesh shows a higher degree of agreement with the regional geological and more close to the geological boundary.4)Elements in-1 0^+80 mesh shows a larger scale and intensity geochemical high background and positive anomaly than-6 0 m esh,particularly in Mo,Sb.Therefore,the optimal sampling fraction of the Beishi area in Guang Dong is-1 0^+80 mesh.

关 键 词：广东北市地区 水系沉积物 粒级试验 地球化学特征 

分 类 号：P632[天文地球—地质矿产勘探]