In september and october 1986, the P.S.C.J.A. and the Institute of Geology of the Academia Sinica organized a joint expedition to Guizhou Province, South China. Fourteen French cavers with eight Chinese scientists explored and surveyed forty kilometers of passages in forty seven caves of Anshun, Zhijin, Ziyun and Luodian areas. Researches into geology, geomorphology and hydrogeology have been made concerning more particularly the underground waters and the cave deposits.
This expedition was the beginning of a profitable collaboration among french and chinese cavers which outcome is this joint report. We all hope that it will further others expeditions to carry on the undertaken work.
The Guizhou province, in Sur les traces de Xu Xiake the oriental part of the Yunnan Guizhou plateau, is 75% covered with carbonated rocks. Climate is subtropical. The hydrogeological system belongs to the Changjiang and Zhujiang drainage basin.
Geological conditions for the development of karst
In the central and south part of Guizhou, nearly all the geological times produced deposits. In the eastern part, the synclines are wide and the foldings gentle. From East to West, the foldings increase with numerous faults and pronounced synclines and anticlines.
Geomorphology and hydrology of the central and south Guizhou
Negatives forms (ouvalas and poljes) and the positives forms (funglin and qiufung) allow to define four types of landscapes, funglin - ouvala, funglin - polje, funglin - erosive plain and qiufung - ouvala or polje.
Since Cenozoïc, three major geomorphological phases took out four erosive surfaces.
Presentation of the surveyed areas and the explored caves
The explorations took part in four counties of the Guizhou province, Anshun, Zhijin, Ziyun, Luodian. The cavers mapped forty kilometers of passages in forty seven caves. The main systems are Santang dongqun, Daxiao Jing and Xiangbi dong. We can notice several exceptional phenomena, the huge shafts of Daxiaocaokou, the strong springs of Daxiao Jing and the big room of Hei Dong.
Chemical composition of the carbonated rocks
The carbonated rocks are essentially very pure limestones and sometimes very pure dolomites. They contain less than five per cent impurities. We discuss about the transference of the metallic elements from the source rock to the concretions.
Guizhou concretions and results of their U series dating
Fifty eight dating determine periods of sedimentation which are compared to the results of the deep sea core V28 239.
Comments on phytokarst
Examples of phytokarts have been observed in the entrance of several caves of the area.
A new cave fish
Dai Ding-yuan describes a new blind fish of a new genus discovered in Daxiao Dong (Luodian).
In the Guizhou province, a good use of the karst could be a chance in economic fields like agriculture, tourist trade. But this ecosystem is weak and must be protected from pollution and ill-regulated industrialization.
The life of the expedition
We discuss in this chapter of the chronology, main events and means of the expedition. Future projects evoked.