陆相页岩油“甜点”井震联合定量评价技术——以济阳坳陷罗家地区沙三段下亚段为例

Well-seismic joint technology for quantitative evaluation of “sweet spot” in continental shale oil:A case study of Lower Es_3 Member of Luojia area in Jiyang Depression

随着常规油气田勘探程度的不断提高,东部老油区特别是胜利油区面临着扩大勘探领域、打开非常规油气勘探局面的新形势和新任务。与北美海相页岩油相比,陆相页岩油具有自身的特殊性:成藏条件复杂,相应的定量评价技术匮乏。为此,以济阳坳陷罗家地区沙三段下亚段陆相页岩油为例,在明确页岩油"甜点"测井响应特征基础上,建立测井定量识别模型,实现了页岩油"甜点"的测井定量识别。同时,探讨页岩油"甜点"中总有机碳含量、岩相类型、裂缝和脆性4项关键要素与叠前、叠后地震信息的关系,形成了多测井曲线约束的总有机碳含量反演预测、基于沉积参数的页岩岩相预测、基于叠后地震属性的缓倾角裂缝密度定量表征和基于叠前弹性参数的页岩脆性表征4大类地震预测技术。最终,以4项关键要素的地震预测结果为基础,以测井定量识别为约束,融合构建"甜点"地震表征模型,实现了对陆相页岩油"甜点"的井震联合定量评价,取得较好的应用效果。

With the continuous improvement of conventional oil and gas exploration,the eastern old oilfields,especially Shengli Oilfield,are facing a new situation and new task of expanding exploration field and opening up situation of unconventional oil and gas exploration.Compared with North American marine shale oil,continental shale oil has its own particularity of complex reservoir-forming conditions and being lack of corresponding quantitative evaluation technology.Therefore,taking the Lower Es3 Member of Luojia area in Jiyang Depression as an example,on the basis of definition of the logging response characteristics of shale oil“sweet spot”,the logging quantitative identification model of shale oil“sweet spot”in Luojia area was established,by which the logging quantitative identification of shale oil“sweet spot”is realized.Meanwhile,the relationship between key geological and engineering factors,including TOC,lithofacies,fracture and brittleness,and pre-stack and post-stack seismic information was discussed.Four categories of unique seismic prediction technologies were generated,including the inversion prediction of TOC under multi-logging curves constraint,the sedimentary parameter based shale lithofacies prediction,post stack seismic data based gentle angle fracture density quantitative characterization,pre-stack elastic parameters based shale brittleness characterization.Finally,based on the seismic prediction results of four key geological and engineering factors and constrained by logging quantitative identification,a“sweet spot”seismic characterization model is constructed,which realizes quantitative evaluation of“sweet spot”in continental shale oil with the well-seismic joint technology,and achieves good application results.