X射线荧光元素录井在川西坳陷须家河组地层划分中的应用

Application of the X-ray fluorescence element logging in the stratigraphic classification in Xujiahe Formation Chuanxi Depression

川西坳陷须家河组油气勘探过程中,由于钻井工艺的改进,导致录井过程中岩屑细小,常规录井手段划分地层存在技术难题。X射线荧光元素录井中的特征元素含量能够指示沉积环境的变化,通过研究建立元素录井地层划分方法,利用硅(Si)、铁(Fe)、钙(Ca)、磷(P)、硫(S)、锰铁比(Mn/Fe)等元素或元素组合的含量变化趋势,识别沉积环境,划分地层。在川西坳陷多口井须家河组地层划分中应用结果表明,该方法能有效地解决油气勘探目前面临的录井难题。

During the oil and gas exploration in Xujiahe Group Chuanxi Depression,the improvement of drilling technology has resulted in small cuttings in mud logging process,which results in a difficulty for the conventional mud logging means to classify strata.The characteristic element content in the X-ray fluorescence element logging can indicate changes in the depositional environment.A method for mud logging stratigraphic classification was set up by studying,which uses trend changes of elements or combination of elements content of silicon (Si),iron (Fe),calcium (Ca),phosphorus (P),sulfur (S),ferromanganese (Mn /Fe) to identify sedimentary environment and classify strata.After the application in the formation of multi wells in Xujiahe Group,Chuanxi Depression,it confirmed that this method can effectively solve current mud logging problems.