江苏启东地区发现浅层天然气气源层与晚更新世末期古土壤层——据江苏1:5万余东镇等七幅区调  

Discovery of the Shallow Gas Source Layer and Late Pleistocene Paleosol in Qidong Area,Southeastern of Jiangsu Province: according to 1:50000 Yudong Town and other six Rigional Geological maps in Jiangsu Province

作　　者：冯文立[1] 季文婷[1] 冯金顺[1] 张平[1] 郭盛乔[1] 程瑜[1] 赵增玉[1] 

机构地区：[1]江苏省地质调查研究院,江苏南京210049

出　　处：《中国地质调查》2015年第2期56-60,共5页Geological Survey of China

基　　金：中国地质调查"江苏1:5万余东镇;吕四镇;其林镇;南阳村;向阳村;启东;江夏幅区调(编号:1212011220537)"项目资助

摘　　要：江苏东南部启东地区开展的1：5万区域地质调查工作已经完成野外工作验收，通过整理分析新获取的地质资料，发现工作区内“下切河谷”地区地表下46～59m处普遍存在棕黄色、灰绿色、灰黑色“硬黏上层”，厚度2—10m不等；局部地区钻孔岩心剖面在本层顶部表现为明显的古土壤层，见根痕构造、钙质结核等暴露成土特征，其下部可见灰黑色富有机质、植物碎屑的粉砂质黏土层。古土壤层的发现证明了本区在末次盛冰期并不完全为下切河谷地区，更新了前人对测区晚更新世末期沉积地层的认识；而厚度0．5～2m不等的富有机质、植物碎屑的粉砂质黏土层为本区浅层天然气提供了气源。The field work of the 1 ： 50,000 regional geological survey on Qidong area, Southeastern Jiangsu has been accepted. Based on the new data,we found that there are brown, celadon, gray-black ＂hard clay bands＂ between 46 -59 m below the surface in the incised valley area, with thickness ranging from 2 m to 10 m. In the top of the ＂hard clay bands＂ in some drilling cores is paleosol which has root-mark structure, calcareous concretions and other exposed soil-forming features; and in the lower part is a grayish black silty clay layer rich in organic and plant debris. The discovery of the paleosol proved that the area is not fully incised valley region in LGM, which updates the understanding on the Late Pleistocene sedimentary strata of the survey area. The silty clay layer rich in organic and plant debris, with thickness of 0.5 -2 m, provided gas source to the shallow gas of the study area.

关 键 词：江苏启东 下切河谷 晚更新世 古土壤 浅层天然气 

分 类 号：P622[天文地球—地质矿产勘探]