陕西绥德地区黄土-古土壤序列地球化学特征及其环境指示意义  

Geochemical Characteristics of Loess Paleosol Sequence and Its Environmental Implications in Suide Area, Shaanxi

作　　者：石浩 岳大鹏 赵景波 覃小锋[2] 刘蓉 王珂 王晓宁 苏敏 SHI Hao;YUE Dapeng;ZHAO Jingbo;QIN Xiaofeng;LIU Rong;WANG Ke;WANG Xiaoning;SU Min(School of Geography and Tourism,Shaanxi Normal University,Xi'an 710119,China;College of Earth Science,Guilin University of Technology,Guilin 541004,China)

机构地区：[1]陕西师范大学地理科学与旅游学院,西安710119 [2]桂林理工大学地球科学学院,广西桂林541004

出　　处：《地球与环境》2022年第1期1-13,共13页Earth and Environment

基　　金：国家自然科学基金重点项目(41930641);陕西能源开发水土保持动态监测信息管理系统(1204010725)。

摘　　要：黄土高原北部的绥德地区处于干旱-半干旱地区,对环境变化的响应十分敏感,通过对黄土-古土壤的研究对比可以探索该区的古环境气候特征、环境变化信息等相关问题。本文对绥德黄土-古土壤进行常量、微量、稀土元素测试分析,并与其他地区黄土的地球化学特征进行了对比。结果表明:绥德地区黄土-古土壤的主要化学成分以SiO_(2)、Al_(2)O_(3)、Fe_(2)O_(3)和CaO为主;与风化程度、成壤强度和各种气候代用指标相关的地球化学参数指示,绥德黄土大部分处于气候干冷的低风化程度阶段,只有S_(2)古土壤形成时期成壤作用较强,风化程度中等,降水最多,处于暂时温暖半湿润气候,剖面的风化强弱和成壤作用序列为S_(2)>S_(3)>S_(4)>S_(1)>L_(4)>L_(3)>L_(2)>L_(1);具有物源指示意义参数显示,绥德黄土-古土壤,与黄土高原其他黄土的物源有所差异,阿拉善高原和鄂尔多斯高原的腾格里沙漠、巴丹吉林沙漠和毛乌素沙漠可能是其主要物源区。The Suide area in the northern part of the Loess Plateau is in an arid/semi-arid area. It is very sensitive to the environmental changes. By comparing the loess paleosol, we can explore the characteristics of the paleoclimate, climate change and other related issues in the area. In this paper, the major, trace and rare earth elements of Suide loess-paleosol are tested and analyzed, and the geochemical characteristics of loess in other areas are compared. The results show that: the main chemical components of loess-paleosol in Suide area are SiO_(2), Al_(2)O_(3), Fe_(2)O_(3) and CaO. The geochemical parameters related to weathering degree, pedogenesis intensity and various climatic substitution indexes indicate that most of Suide loess was in the low weathering stage of dry and cold climate. Only S_(2) paleosol formation stage has strong pedogenesis, moderate weathering degree and the most precipitation, which was in a temporary warm and semi humid climate. The sequence of weathering intensity and pedogenesis is S_(2)>S_(3)>S_(4)>S_(1)>L_(4)>L_(3)>L_(2)>L_(1). The provenance indicator parameters show that the provenance of Suide Loess-Paleosol is different from that of other loess in Loess Plateau. Tengger Desert, Badain Jaran Desert and Mu Us Desert in Alxa Plateau and Ordos Plateau may be the main provenance areas.

关 键 词：绥德 黄土-古土壤 地球化学特征 风化强度 气候变化 物源 

分 类 号：P595[天文地球—地球化学] P534.63[天文地球—地质学]