中国南方红土年代地层学与地层划分问题  

CHRONOSTRATIGRAPHY AND STRATIGRAPHIC DIVISION OF RED SOIL IN SOUTHERN CHINA

作　　者：袁宝印[1] 夏正楷[2] 李保生[3] 乔彦松[4] 顾兆炎[1] 张家富[2] 许冰[1] 黄慰文[5] 曾荣树[1] 

机构地区：[1]中国科学院地质与地球物理研究所,北京100029 [2]北京大学城市与环境学院,北京100871 [3]华南师范大学地理科学学院,广州510631 [4]中国地质科学院地质力学研究所,北京100081 [5]中国科学院古脊椎动物与古人类研究所,北京100044

出　　处：《第四纪研究》2008年第1期1-13,共13页Quaternary Sciences

基　　金：国家自然科学基金项目(批准号:40471139和40472088)资助

摘　　要：南方红土是我国热带、亚热带以各类岩石和第四纪松散沉积物为母质发育的红色风化壳,也是我国分布最广的第四纪土状堆积。本文在探讨第四纪松散沉积物上红色风化壳的形成机制的基础上,根据风化壳发育程度将其划分为砖红土风化壳、红壤土风化壳和红化土风化壳3种类型。南方地区第四纪松散沉积物主要有河流相沉积、滨海相海滩砂和海岸风成砂——"老红砂"以及以下蜀土为主的风尘堆积。近年来在上述沉积物中多处发现旧石器遗址,促进了南方红土的地层年代学研究。根据前人及近期对南方红土的研究成果,讨论了南方红土的年代地层学问题,提出了以风化壳岩性特征为基础的岩石地层单位初步划分框架:老红砂划分为中更新统北海组、晚更新统晋江组;风尘堆积划分为中更新统宣城组、晚更新统下蜀组;河流相沉积只划出中更新统白沙井组,晚更新统留待以后研究再划出。Red soil in southern China is distributed to the north till the south of the Qinling Mountain-Huihe River line, and to the west till the east of Tibet,with an area of about 200 × 10^4km^2. It has the widest distribution in the form of Quaternary earthy deposits in China. Abundant information about geology, environment, climate, and Paleolithic culture has been available on it. It＇s significance can be compared favourably with loess deposits in North China. In this paper,we only focus on the red weathering crusts developed on the Quaternary loose sediments. The Quaternary loose sediments in southern China mainly consist of beach sand and coastal dune sand-the ＂Old Red Sand＂, fluvial sediments and eolian deposits including Xiashu loess. Recently, some Paleolithic sites have been found in these deposits,which facilitate study of the chronostratigraphy of the red soil. Firstly this paper focuses on exploring the forming mechanism of the red weathering crust on the Quaternary loose sediments. Secondly we provide the results of chronostritigraphy of red weathering crust in Baise Basin of Guangxi Province,Wenchang County of Hainan Province, Jingjiang Region of Fujian Province, and Xuancheng Area of Anhui Province. The accumulation period of the parent material and the ages of the red weathering crust were discussed. The contemporaneous zoning pattern of the red weathering crust during the climate change process was also discussed. Based on the above results and discussion, following general conclusions can be obtained： 1. Red soil in southern China is a weathering crust from different parent rocks and Quaternary loose sediments in the tropical and subtropical zones. 2. According to the degree of weathering, the weathering crusts in southern China can be divided into three types：（1） Laterite weathering crust. It was formed in strong weathering process of desiliceous and enriched bauxite, with formation of gibbsite. （2） red soil weathering crust. It was shaped during week process of desiliceous

关 键 词：南方红土 红色风化壳 网纹红土 地层划分 

分 类 号：P534[天文地球—古生物学与地层学]