江汉平原潜江ZK-20钻孔沉积物磁化率及对沉积环境指示规范.doc

本科毕业论文（设计） 题目：江汉平原潜江ZK-20钻孔沉积物磁化率 ①通过钻孔采样分析可知，江汉平原是典型由河间洼地构成的洪泛平原，自第四纪冰川期以来，平原河床相、洪泛相、湖相、沼泽相沉积层交替出现，反映了江汉平原河湖交替的环境演化格局，而沉积物岩性分析也可明显的看到砾石层十分发育表明，沉积环境为水动力强的河流相沉积环境。 ②通过对沉积物磁性的分析，体积磁化率反映了环境的波动变化，频率磁化率反映了环境的具体变化趋势，从目前所得数据处理结果结合岩性分析可知江汉平原的大致古气候变迁，总体趋势为冰盛期—冰消期—温湿环境—干冷环境—气候波动频繁—温湿期—干冷期—温湿期。 关键词：江汉平原 环境磁学 潜江钻孔ZK-20 环境指示 Abstract As the alternative index reflecting the climate and environment change, sediment magnetic characteristics have been widely used in the research of loess deposits, ocean and some plateau and drought are closed in of the lake sediments, but rarely in the research of Jianghan plain. This study aims to analyze sediment magnetic characteristics of the quaternary outcrop profile in Jianghan plain, then considering the profile lithological features, the correlation between the coefficient characteristics of magnetic susceptibility and frequency magnetic susceptibility and the lithological characteristics is compared, so as to get a comprehensive understanding of the denotative significance which the magnetic parameters of open basin in Yangtze river basin means on the climate and environment index. Finally, the evolution laws of the ancient climate and environment in Jianghan plain since the late Pleistocene can be recovered. In the thesis, firstly through the use of the drawing software Grapher the curve of magnetic parameters change can be drawn and further be analyzed. Then, according to the curve changing laws, and in the combination of the profile lithologic features and the characteristics of sedimentary environment and sediments, the evolution process of the sedimentary environment and the ancient climate in every stage can be preliminary decided. In the next part, on the basis of the above analyzing results, magnetic parameters are divided into many segments which can be further analyzed, corrected and explained. From the above analysis of the magnetic parameters of the profile sediments in Qian Jiang, and in the c