安徽东至华龙洞洞穴发育与古人类生存环境
发布时间：2018年01月05日
摘要：安徽东至华龙洞是2006年新发现的一处重要的中更新世古人类遗址,因出土直立人头盖骨化石和相关石制品及哺乳动物化石而为学术界所关注。对华龙洞遗址的区域地质与洞穴发育特征进行解析,对堆积物蕴含的哺乳动物群、黏土矿物和氧化物等进行分析和测试,结果表明,华龙洞位于扬子地层区内,处在下扬子地层分区和江南地层分区过渡地带。遗址发育于下古生界中寒武统团山组条带状微晶灰岩岩系内,周边地貌以低山-丘陵-湖泊平原为主。洞穴发育初期由沿围岩裂隙运移的裂隙水引起,溶蚀方式以垂直渗流为主,后期逐渐转为水平流向的溶蚀方式。洞口开口方向为南偏西,洞内堆积物较少,洞外为一岩溶洼地,其间富含以下部角砾层和上覆红色黏土为主的堆积物,堆积营力主要为重力作用。遗址形成于北亚热带季风气候区北缘,总体为温暖湿润环境,堆积物充填早期气候相对晚期较为干凉,后期逐渐转为相对温暖湿润环境,动植物资源繁盛,有利于古人类生存、活动。华龙洞古人类生存环境的研究对揭示长江下游中更新世古人类适应行为与生存环境具有重要意义。
关键词：直立人; 洞穴发育; 生存环境; 中更新世; 华龙洞;
基金资助：北京市自然科学基金项目(8163047)；国家自然科学基金重点项目(41630102))；
Abstract:
The Hualongdong cave, located in Pangwang villege, Yaodu town, Dongzhi County of Anhui Province at latitude 30°06′34.1"N and longitude 116°56′54.2"E, and 40 m above sea level, was discovered in 2006, where unearthed Homo erectus skulls, stone artifacts, and large number of animal fossils. The cave bears great significance on the study of human evolution, lithic technology, and adaptive behaviors of human in South China and has therefore raised great attentions from the public and scholars. Preliminary U- series dating and study of mammalian fauna assemblages indicate that early hominin colonized the site most probably in Middle Pleistocene. This paper devotes our work on regional geology, cave development and mammalian fanua, and analyzing data of clay minerals and oxides from sediments.
The cave, as part of the Yangtze stratigraphic region, is geologically situated in the transitional zone between the stratigraphic subzones of the Lower Yangtze and the South of Yangtze. The cave is developed in the stripped micrite limestone of the Tushan Formnation, Middle Cambrian. The site and its adjacent area are dominated by low mountains, gentle hills and lake plains. The cave is formed by the movement and dissolution of fracture water along the verticle fissures in the early stage, and then by horizontal water movement later on for further karst development. The entrance of the cave opens to the southwest with few deposits in the cave, while a karst depression was developed outside the cave. Due to the collapse of the stone outside the current entrance of the cave, abundant sediments including breccia and red clay are deposited within the depression, with a total thickness of more than 4 m. Gravity is the predominate agent of deposition. Human fossils, stone artifacts, and animal remains are recovered from the layers 3 and 4 at the lower part of the section, with a total thickness more than 2 m.
In order to reconstruct the environmental background and the impact
of human activities, systematic analysis of the mammalian fauna, clay
minerals as well as oxides from sediments have been carried out by the
authors. It is inferred that the climate and environment were warm and
humid then to some extent, and favorable for human survive, as a typical
climate background on the north margin of the north subtropical zone.
It should be noted that human fossils, stone artifacts, and mammalian
fossils are mainly distributed in the layer 3 and 4 of breccia or the
lower part of the section, of which the environment was relatively
cooler and drier than the environment of the upper part of the section.
The climate and environment were optimal to flourish of grass, bamboo
grove, and forest, as well as animals, which might lead to the
intensified occupation of early hominins during the period while the
layers 3 and 4 was formed in Middle Pleistocene. In brief, for study of
human occupation of the region during Middle Pleistocene, the
Hualongdong cave may provide significant information.
《海洋地质与第四纪地质》2017 37(3): 169-179