On August 13, a scientific drilling penetrated 1050.24 meters into the salt lake sediment in the Sanhu (three lakes) area of the Qaidam Basin in northwest China 's Qinghai province, well-known for its salt lake resources. It is the deepest drilling in the region so far.
The 62-day drilling operation, named ISL1, started on June 6, 2006 by researchers from the CAS Qinghai Institute for Salt Lakes in collaboration with the CAS Institute of Microbiology, the CAS Institute of Geology & Geophysics and the Lanzhou Center for Hydrocarbon Research.
Besides the 947.52m-long core with an average recovery rate of 94.73%, the scientists sampled 271 specimens of halophilic bacteria, 30 specimens of methane bacteria and 51 specimens of natural gas from drilling site. Among the four obvious gas showings during the drilling, one at the depth of 185m shows a more than 3m-high blowout. This indicates a promising perspective for exploiting the locality's shallow natural gas deposits.
The drilling operation is designed to find out the natural resources badly needed for the national development such as salt sediments, natural gas and microbiological resources in extreme conditions in the Qaidam Basin. Its research is focused on the following four aspects: paleo-environmental mechanism through for the salt forming in the lakes; the biogenic mechanism of the natural gas trove in the Quaternary; the evolutionary course of the characteristics of the salt lakes, and paleo-climate data recorded under extreme conditions.
The research project has been carried out by combining the formation about changes in the special natural conditions innate to the Qinghai-Tibet Plateau (such as the hostile environment on the Plateau, the westerly circulation and East Asian monsoon) and exploitation of the natural legacies in Qinghai Province such as the salt resources, biogenic gaseous and microbe deposits.
China's salt lake science was founded by the pioneering research work conducted by Chinese geologists including CAS Members LIU Dagang, YUAN Jianqi, ZHANG Pengxi, GAO Shiyang. Based on this academic build-up, the drilling operation at the Qaidam Basin will turn a new page for further exploration of the salt lake resources. It is expected to provide eye-opening theories on the mineralization and biogenesis of the salt and hydrocarbon trove during the Quaternary epoch in the Basin so as to update people's understanding of their generative processes and enrich the contents of related disciplines. In practical applications, in addition, the research project is to offer innovative scientific grounds for mineral prospecting & comprehensive exploitation of China's largest salt lake of Qarhan in the Basin and for microbiological engineering in the national production of chemical salts as well as the increase of national hydrocarbon output. Furthermore, the project will make substantial contributions to the province's economic development, supplementary reserves in the proven resources set for the national program of natural gas shipment from the hinterland China to the coastal areas and the implementation of the national program for the western China's large-scale development.
While the work on ISL1 is being finished, the design and preparations for the drilling of the ISL-2 and ISL-3 are under way.
