In recent years,the Yanchang shale-oil formations of the Ordos Basin are rich in reserves with complex lithology and structure characteristics,low porosity and low permeability,and weak anomalies for oil and water dis...In recent years,the Yanchang shale-oil formations of the Ordos Basin are rich in reserves with complex lithology and structure characteristics,low porosity and low permeability,and weak anomalies for oil and water discriminations,have been the key targets of unconventional oil/gas resource exploration and development in the relevant areas.The joint acoustic-electrical(AE)properties can be used to interpret reservoir lithology,mineralogy,pore structure,and fluid saturation.To conduct tests of thin section analysis,X-ray diff raction,and ultrasonic and electrical experiments at diff erent pressures and saturation degrees,cores from the shale-oil formations in the Q area of the basin are collected.The variations in AE properties with respect to clay content,porosity,pressure(microfracture),and saturation are analyzed.The experimental results indicate that the rock physics behaviors of sandstones with diff erent clay contents vary significantly.The AE properties of clean sandstones are basically dependent on the microfractures(pressure),while for muddy sandstones,the clay content is an important factor affecting the responses.The target reservoir consists of interbedded sandstone and shale layers.The AE equivalent medium equations and the Gurevich theory are applied to establish the joint models for the diff erent lithologies and simulate the variations in AE properties with respect to fluid type,pore structure,and mineral components.The three-dimensional joint templates of clean and muddy sandstones,as well as shale,are developed based on the elastic and electrical attributes and then calibrated using the experimental and well-log data.The reservoir properties are estimated with the templates and validated by the log data.The results indicate that the joint templates based on lithology characteristics can eff ectively characterize the properties of interbedded sandstone and shale layers.Furthermore,the combined application of AE data provides more beneficial information for the assessment of rock properties,leading to precise estimates that conform with the actual formation conditions.展开更多
一、煤田地质特征我矿位于徐州东北潘家庵煤田西部边缘,走向自西北转为东南,长5.2公里。上部为煤层露头,深部至-900水平。面积9.74公里2。煤系属石炭二迭纪地层。可采煤层6层,总厚度9米左右。其中石盒子系下层煤（三层）为主采煤层,平...一、煤田地质特征我矿位于徐州东北潘家庵煤田西部边缘,走向自西北转为东南,长5.2公里。上部为煤层露头,深部至-900水平。面积9.74公里2。煤系属石炭二迭纪地层。可采煤层6层,总厚度9米左右。其中石盒子系下层煤（三层）为主采煤层,平均煤厚4米左右,埋藏稳定。属倾斜厚煤层。山西系 B 层煤（七层）为局部可采,分布在矿井北翼 F12断层以北,展开更多
基金supported by the National Natural Science Foundation of China (Nos.41974123,42174161)the Jiangsu Innovation and Entrepreneurship Plan and the Jiangsu Province Science Fund for Distinguished Young Scholars (grant no.BK20200021).
文摘In recent years,the Yanchang shale-oil formations of the Ordos Basin are rich in reserves with complex lithology and structure characteristics,low porosity and low permeability,and weak anomalies for oil and water discriminations,have been the key targets of unconventional oil/gas resource exploration and development in the relevant areas.The joint acoustic-electrical(AE)properties can be used to interpret reservoir lithology,mineralogy,pore structure,and fluid saturation.To conduct tests of thin section analysis,X-ray diff raction,and ultrasonic and electrical experiments at diff erent pressures and saturation degrees,cores from the shale-oil formations in the Q area of the basin are collected.The variations in AE properties with respect to clay content,porosity,pressure(microfracture),and saturation are analyzed.The experimental results indicate that the rock physics behaviors of sandstones with diff erent clay contents vary significantly.The AE properties of clean sandstones are basically dependent on the microfractures(pressure),while for muddy sandstones,the clay content is an important factor affecting the responses.The target reservoir consists of interbedded sandstone and shale layers.The AE equivalent medium equations and the Gurevich theory are applied to establish the joint models for the diff erent lithologies and simulate the variations in AE properties with respect to fluid type,pore structure,and mineral components.The three-dimensional joint templates of clean and muddy sandstones,as well as shale,are developed based on the elastic and electrical attributes and then calibrated using the experimental and well-log data.The reservoir properties are estimated with the templates and validated by the log data.The results indicate that the joint templates based on lithology characteristics can eff ectively characterize the properties of interbedded sandstone and shale layers.Furthermore,the combined application of AE data provides more beneficial information for the assessment of rock properties,leading to precise estimates that conform with the actual formation conditions.
文摘一、煤田地质特征我矿位于徐州东北潘家庵煤田西部边缘,走向自西北转为东南,长5.2公里。上部为煤层露头,深部至-900水平。面积9.74公里2。煤系属石炭二迭纪地层。可采煤层6层,总厚度9米左右。其中石盒子系下层煤（三层）为主采煤层,平均煤厚4米左右,埋藏稳定。属倾斜厚煤层。山西系 B 层煤（七层）为局部可采,分布在矿井北翼 F12断层以北,
