Geochemical characteristics of soil bromine in Songliao Basin and its indication to oil and gas

Bromine is an important member of the halogen family, nevertheless, reports on its use for oil and gas exploration have not been seen in spite of the fact that good results have been achieved in applying iodine to oil and gas prospecting. Based on an analysis of near-surface factors influencing soil bromine, the authors used multi-purpose geochemical prospecting data over an area of 8.15×104km2 in central Songliao Basin to verify the significance of geochemical anomalies of surface soil bromine and deep soil bromine for the indication of oil and gas. A huge surface geochemical mega-province and a huge deep geochemical ring of soil bromine were discovered in the central Songliao Basin, which are related to oil- and gas- rich belts, large and medium oil and gas fields as well as volcanic gas reservoirs. The supergene geochemical process of soil bromine, in conjunction with micro-infiltration of oil and gas, is the main mechanism creating the huge surface province and the deep huge ring; however, the supply of abundant material from the oil- and gas- rich belts, together with large and medium oil and gas fields is essential for huge bromine geochemical anomalies. In conclusion, bromine is an auxiliary index for strategic oil and gas geochemical mapping.