克拉2气田地表为山丘、冲沟及河流，地震资料录取和处理难度大；目的层以上为高陡地层，岩相、厚度变化大，盐层、石膏、软泥、高压水层发育；需要准确预测复杂地质层位深度以防漏、卡、溢、喷。用实例阐述了常规的邻井层位厚度对比法和地震剖面法预测新井层位的局限性及误差产生的原因，提出了依据新完钻井不断修正层速度构造成图预测复杂层位界面深度的方法。该方法的应用，提高了克拉2气田复杂地层预测的精度，推广到迪那2气田的应用中也取得了良好的效果，对于其他类似或大井距油气田的钻井地质设计和跟踪具有借鉴意义。

          The surface of Kela 2 gas field is hills, stormed cracks and rivers; it's difficult to collect and process seismic data. Above the reservoir of interest is high and cliffy formation which has variable lithofacies and thickness, and has developed salt bed, gypsum, mud and hi\|pressure aquifer. To prevent leak, check, overflow and blowout, it's necessary to predict geologic position depth accurately. We elaborate the limitation and error of adjacent well position depth correlation method and seismic profile method through examples, and present a method that uses structural diagrams to predict geologic position depth under complex structures. The application of the new method increased the accuracy in predicting complex geologic position depth of the Kela 2 gas field, achieving good results. The method can be for reference in instructing drilling geologic design and drilling trace on other comparable or wide spacing fields.