中扬子地区长兴组生屑滩储层预测

Prediction of Bioclastic Beach Reservoir of Changxing Formation in Middle Yangtze Region

晚二叠世长兴组是中扬子地区礁滩储层最为发育的层位之一,可分为生物礁储层和生屑滩储层。长兴组生屑滩储层具有具有低电阻、低GR、中高声波的特点,由于厚度薄、岩性组合复杂、在地震剖面上为响应特征不明显,难以通过经典的相控储层预测技术进行预测。本文利用电阻率曲线作为敏感参数曲线,使用波形指示反演技术(SMI)对中扬子地区长兴组生屑滩储层进行了预测,识别出建南三维区探明储量范围之外生屑滩圈闭群2个,总面积147.48 km2。其中南部生屑滩7个,圈闭面积21.24 km2,预计圈闭资源量27.3 ×108 m3;北部生屑滩4个,圈闭面积126.24 km2,预计圈闭资源量124 ×108 m3,其中最大的北1号已钻探。南部未钻探目标主要为南5号圈闭,面积7.39 km2。

Changxing Formation in the Late Permian is one of the most developed reef beach reservoirs in the middle Yangtze region, which can be divided into biological reef reservoir and bioclastic beach reservoir. The bioclastic beach reservoir of Changxing formation has the characteristics of low resistance, low GR and medium high sound wave. Due to its thin thickness, complex lithologic combination and unclear response characteristics on the seismic profile, it is difficult to predict by the classical facies controlled reservoir prediction technology. In this paper, the resistivity curve is used as the sensitive parameter curve, and the Seismic Motion Inversion (SMI) is used to predict the bioclastic beach reservoir of Changxing Formation in the middle Yangtze region. Two bioclastic beach trap groups outside the proved reserves of Jiannan 3D area are identified, with a total area of 147.48 km2. Among them, there are 7 bioclastic beaches in the south, with a trap area of 21.24 km2 and an estimated trap resource of 27.3 ×108 m3;There are 4 bioclastic beaches in the north, with a trap area of 126.24 km2 and an estimated trap resource of 124 ×108 m3, of which the largest North 1 has been drilled. The undrilled target in the south is mainly South 5 trap, with an area of 7.39 km2.