三维定量荧光图谱法在陆丰凹陷储集层流体性质快速识别中的应用

Application of 3D quantitative fluorescence atlas method to rapid identification of reservoir fluid properties in Lufeng sag

陆丰凹陷不同时期储集层物性差异大,尤其是文昌组发育低孔隙度低渗透率储集层和湖相泥岩。作为成熟烃源岩,泥岩的测、录井特征常相近甚至好于邻近储集层,给流体性质识别带来困扰。三维定量荧光录井指纹图谱中包含丰富的流体类型信息,通过分类归纳其特征,能够较好地反映流体性质。通过对陆丰凹陷22口井232层460张指纹图谱的分析研究,按照三维定量荧光平面图谱形态,将陆丰凹陷图谱划分为L形、小L形(可分为A类和B类)、长条形、心形和一字形5大类,并以小L形和主峰在左下的单峰长条形为例,通过精细分类描述不同类型流体特征,建立指纹图谱流体类型识别标准。经过新井验证,该方法流体类型识别准确率达到了97.1%,能很好满足现场应用。随着研究的进一步深入和完善,更易于在其他区块进行推广。

The reservoir physical properties of Lufeng sag vary greatly in different periods,especially the low porosity and low permeability reservoirs and lacustrine mudstone developed in Wenchang Formation.As the matured source rock,the well logging and mud logging characteristics of mudstone are often similar to and even better than those of adjacent reservoirs,causing troubles to the identification of fluid properties.The 3D quantitative fluorescence logging fingerprint atlas contains abundant fluid type information,and it can reflect the fluid properties well by classifying and summarizing its characteristics.Through analysis and study of 460 fingerprint atlas of 232 layers from 22 wells in Lufeng sag,the fingerprints of Lufeng sag can be divided into five categories:L-shape,small L-shape(class A and class B),strip,heart and 1-shape according to the 3D quantitative fluorescence planar spectrogram morphology.Taking the small L-shape and the single peak long strip shape with the main peak at the bottom left as examples,the characteristics of different types of fluid were described by fine classification,and the identification standard of fluid type in fingerprint was established.Verification of the new well shows that the accuracy of fluid type recognition is 97.1%,the proposed method can fully meet the field application,with further deepening and improvement,it is easier to generalize in different blocks.