Water in the Sahara

摘要

<正> Petrologists~1-experts in the study of mineral-bearing rocks-have for some time now held the believe that deep down beneaththe Sahara~2 there lay enormous untapped sources of oil,minerals,and natural gas.After months,even years,of surveying,chartingand analysing various possible sites in the desert,the order was giv-en to haul drill-rigs~3 to some of the sites and put the theories to thetest.