【摘要】 储层预测、评价是勘探阶段井位部署的主要依据,目前主要采用地震属性、频谱分解和波阻抗反演技术预测砂体分布,基本停留在平面发育位置、规模的定性预测程度,难以满足日益复杂的岩性油气藏精细勘探需求,缺乏砂体厚度定量精细预测技术.为此,首先根据目标区沉积环境认识以及砂体叠置关系建立正演地质模型,并且在二维全波场正演模拟分析的基础上,定性选出与砂体发育程度关系紧密的地震属性类别;然后通过邻区已钻井的精细测井解释砂岩厚度与井点位置地震属性制作二维散点交会图,利用Kendall指示法分析其相关性,根据有效数的大小优选出二、三种相互独立的地震属性进行数据融合,同时确定出砂岩厚度值与各属性值的数学映射关系;利用该数学映射关系将目标砂体的属性值直接转化为砂体厚度值;最后对各砂体厚度值进行距离加权平均法抽稀,自动勾绘砂体厚度等值线图,若目标砂体过已钻井,则进一步做井点厚度校正.相对于传统的依据沉积规律,通过测井解释厚度的人工勾绘技术和纯地震预测技术而言,井点控制、融合属性约束下的自动成图技术综合了测井解释的纵向高精度和井间信息连续密集优势,砂体纵横向发育规模的预测精度更高、结果更加可信.歧南地区应用实践证实了方法的可行性与精确性,为该区的井位部署提供了可靠依据,提高了钻探成功率.该方法对于砂体厚度精细预测具较高的实用价值.更多还原

【Abstract】 Prediction and evaluation is the main basis for well deploy at exploration phase. At present,commonly used methods of reservoir prediction mainly include seismic attributes, spectrum decomposition and wave impedance inversion,these technologies are qualitative methods to predict reservoir,can’t met the needs of fine exploration for lithological reservoir and lack quantitative prediction technology for sandstone thickness.In order to quantitative predict sandstone thickness,the Qinan area of Qikou Sag is located,studied the prediction technical by seismic and logging data.Firstly,analysis the depositional setting and the overriding relationship of sandstone by geology and seismic data,according to above results establish the forward modeling,and qualitative choose seismic attributes that closed sandstone thickness and distribution on the basis of forward modeling results.Secondly,fine interpret the sandstone thickness by logging in adjacent and extract seismic attribute at well point,then make crossplot of above two parameters,and analysis the correlation using Kendall method, further mix selected independent of each other seismic attributes,meanwhile fitting nonlinear mathematical mapping relationship between sandstone thickness and mixed seismic attribute of drilled well,next automatically calculate the sandstone thickness using the nonlinear mathematical mapping relationship.Finally,dilute the sandstone thickness from calculated results by distance weighted average method and get preliminary thickness distribution map,if target trap has the drilling,the further do well point thickness correction.Compared with the commonly used methods of artificial drew and pure seismic technology,this technology combined the longitudinal precision of log interpretation and continuous dense advantage of seismic data,so the prediction results have higher precision but also more reliable.The error between the predicted sandstone thickness and measured thickness of the sandstone of drilled wells is very small,which fits well with sand sections in the wells.Thus the effectiveness of this technology is verified.更多还原