松辽盆地中部土壤碘的战略性油气勘查

摘要

Use of soil iodine for oil and gas prospecting in the past 40 years has demonstrated that soil iodine is an auxiliary index for tactical oil and gas prospecting,but its relevance to the strategic oil and gas prospecting has never been reported before.With analysis of near surface factors influencing soil iodine,multi-purpose geo-chemical prospecting data over an area of 81 ,500 km2 in the central part of Songliao Basin was used to verify the significance of geochemical anomalies in surface soil iodine (1 point/4 km2 )and soil iodine (1 point/1 6 km2 ) to the indication of oil and gas,leading to the discovery of a regional geochemical anomalies of soil iodine in the form of a huge ring related to oil and gas for the first time.Investigation indicates that the regional geochemical anomaly in soil iodine is mainly linked to medium to large oil and gas fields and hydrocarbon-rich depressions, and the deep soil sampling density of 1 point/1 6 km2 is fairly sufficient to strategic oil and gas prospecting.The main factors which have bearing on soil iodine include topography and landscape,soil type,soil pH,human farming,rivers.%近40年土壤碘的油气勘查表明，土壤碘是战术性油气勘查的一个辅助指标，但是土壤碘的战略性油气勘查意义却未见报道。应用松辽盆地中部8．15万km2的多目标地球化学勘查数据，在研究土壤碘的近地表影响因素的基础上，试验了表层土壤碘（1个点／4 km2）和深层土壤碘（1个点／16 km2）的地球化学异常对油气的指示意义，首次发现了与油气有关的土壤碘的巨环状地球化学异常。研究表明，土壤碘的地球化学异常主要与大中型油气田和富生油凹陷相联系， 1个点／16 km2的土壤采样密度可以较好地进行战略性油气勘查。松嫩平原土壤碘的影响因素主要有地貌景观、土壤类型、土壤pH值、人为耕作和河流等因素。