G-LOG技术在西藏伦坡拉罗马敌库构造的应用

The G-log technique applied to Luomadiku structure in Lunpola basin of Tibet

伦坡拉盆地位于海拔4600m以上的藏北高原，为小型陆相沉积盆地。罗马敌库构造位于盆地爬错凹陷北斜坡，处于扇三角洲前缘带，砂体发育。运用G－LOG技术于高原三维地震资料处理中，其目的是搞清砂体横向变化规律，进行探索性的储层横向预测与油气识别，为该区的油气勘探提供科学依据。处理中，充分利用测井资料做好合成地震记录和井旁单道反演，为空间低频速度模型体的建立提供质量保证，使处理结果较为客观、可信。为避免G－LOG剖面在解释工作中的多解性和盲目性，在加强对测井资料分析的基础上，利用G－LOG的相对速度剖面对实际资料进行储层预测和油气识别，取得了良好的地质效果。

The Lunpola basin, which is situated on the northern Tibet plateau with an elevation of more than 4600m, is a small-scale land sedimentary basin. The Luomadiku structrue is located on the north slope of the Pacuo sag in the basin. The structure is in the forward opsition of fan delta and the sand bodies are well developed. The G-log technique is utilized in the 3-D seismic data processing in the plateau. It aims to understand the lateral variation law of sand bodies, perform the exploratory reservoir lateral prediction and hydrocarbon identification, and provide scientific basis for the oil and gas exploration in the area.In the processing, well log data are fully utilized to produce synthetic seismogram and do naar-well single trace inversion. It provides quality assurance for the building of spatial low-frequency velocity model volume and makes the processing result objective and convincible. In order to avoid the ambiguity and blindness in the interpretation of G-log sections, I use the G-log reative velocity section to perform reservoir prediction and hydrocarbon identification for real data on the basis of enhancing well log data analysis. A good geological effect is achieved.