桂林甑皮岩遗址岩溶地下水水害成因及防治对策

Causes of Karst Groundwater Damage to the Zengpiyan Ruins of Guilin and the Prevention and Control Countermeasures

桂林甑皮岩遗址自1973年试掘以来,出土了古人类骨架、火塘、墓葬、石器、蚌器、陶器、动植物化石等大量的较为珍贵的实物资料,成为我国南方的一个重要的新石器人类遗址。2001年被列入国家级重点文物保护单位。然遗址在1994年汛期遭受洪水浸泡,致使多个探方隔梁崩塌,探方文化土层先后出现不同程度的崩塌或下沉现象。为了暂时性抢救探方的文化层,曾先后采取了一系列的抢救性加固与保护措施,如建混凝土挡土墙,缓解了探方隔梁崩塌,但仍不能从根本上解决丰雨季节地下水快速涨落所带来的隐患。本文在调查分析有关资料的基础上,认为甑皮岩遗址文化堆积土层下部的灰岩中岩溶管道非常发育,地下水位随每年丰枯季涨落所产生的水动力作用导致文化土层软化,土层颗粒冲刷流失、掏空而形成土洞,最终引起文化层崩塌、下沉。根据这一成因,笔者认为:查明遗址下部及其周围地下溶洞、管道、地下河、大的溶隙等较大尺度的导水介质,并对其进行适当封堵,是防止洪水期地下水速涨速落对遗址文化层造成破坏的重要措施。

Since the beginning of the trial excavation of the Zengpiyan Ruins in Guilin in1973,large quantities of precious material objects were unearthed,such as skeletons of the ancients,fire ponds,tombs,stone implements,clam tools and animal or plant fossils.These achievements have made the Zengpiyan Ruins one of the important ruins of the new stone implement times,which was therefore put on the list of the national key preservation units of cultural relics.During the flood season of 1994,the ruins were soaked in water,which resulted in the collapse of the exploratory shaft beam as well as some other serious damages.Some rescue and protection measures were taken,which,however,failed to eliminate the hidden trouble caused by rapid falling and rising of underground water during the rainy season.Based on an investigation and analysis of the relevant data,the authors put forward the following opinions：Karst channels are extensively developed in limestone in the lower part of the cultural accumulated soil layer,and the hydrodynamic action caused by rising and falling of the underground water level during the alternate high flow and dry seasons results in the softening of the cultural soil layer,the erosion of soil grains,the formation of soil holes and the eventual collapse and sinking of the cultural bed.In view of such a situation,we should find out such large-scale water-conduit media as underground karst caves,channels,groundwater rivers and large karst fissures and try to block up them so as to prevent the damage to the cultural bed caused by the rapid rising and falling of the underground water during the flood period.