特深科学钻探的关键问题

The key problems of ultra-deep drilling engineering

科学钻探是当今世界各大国竞相开展的科学探索活动.超过万米孔深的特深钻探更是堪比宇航难度的大科学工程,也是"上天、下海、入地、登极"四大人类科学梦想中难度最大、迄今进展最慢的科学工程.本文探讨了特深钻探的主要难题,并提出了今后攻克这些难题的基本思路.

Ultra-deep scientific drilling,a large scale scientific research project successively implemented by the major countries all over the world,is a typical representative project which reflects the entire scientific and technological strength of a country,also the most difficult and slowly developed scientific project among the four great scientific dreams of the mankind,i.e.,going up to the outer space,reaching the interior Earth,entering into the deep sea and probing into the north and the south poles.Due to the isolation by lithosphere,it is very hard to observe the information of the interior earth.At present,geophysical and geochemical methods are mainly employed for this purpose,though fast and simple,with the information obtained of indirect,deduced and multi-interpreted.As scientific drilling can directly obtain underground materials,structure and information,based upon which the geophysical interpretation result can be corrected,it becomes an inevitable way to obtain a great breakthrough for earth science.However,hampered by lack of well-developed technique and of economic reasons,drilling to approximately 10 km deep is only realized in few areas at present,with the drilling depth only one tenth of the lithosphere thickness,far inferior to the requirement for observing the upper and the lower mantles.To deeply understand the earth,drilling must penetrate into the earth deeper and deeper.The implementation of ultra-deep scientific drilling project over 10000 m will greatly promote the development of drilling equipment,instruments and drilling technologies,thus help to improve the application level of the related materials and electronic elements under the extreme conditions.Technically,ultra-deep scientific drilling engineering will face three key problems,namely high temperature,high pressure and high crustal stress,which cannot be resolved as yet by using the existing well developed technique,and to solve these key problems will cost huge,expend long time and face high risk.For this reason,this paper puts forward several principal countermeasures and some research areas,to which attention should be paid during the implementation of the engineering construction.