• 主题
高级搜索  >
历史搜索 清空历史
首页> 外文会议>Society of Petrophysicists and Well Log Analysts Annual Logging Symposium >A NEW APPROACH FOR CONSTRUCTION OF HIGH RESOLUTION EARTH MODEL USING DYNAMIC IMAGES FOR THE EVALUATION OF VERY THIN BED RESERVOIRS OF KRISHNA GODAVARI BASIN EAST COAST, INDIA
【24h】

A NEW APPROACH FOR CONSTRUCTION OF HIGH RESOLUTION EARTH MODEL USING DYNAMIC IMAGES FOR THE EVALUATION OF VERY THIN BED RESERVOIRS OF KRISHNA GODAVARI BASIN EAST COAST, INDIA

机译：一种新方法，用动态图像建设高分辨率地球模型，以评估克里希纳戈达瓦里盆地东海岸的薄薄床储层

获取原文
页面导航
  • 摘要
  • 著录项
  • 相似文献
  • 相关主题

摘要

Accurately defined set of bed boundaries i.e. an earth model from high resolution logs is essentially required to be used in combination with a set of forward models for the low resolution logging tools to perform an inversion for thin bed evaluation. Deep water Tertiary reservoirs of Krishna Godavari basin are generally very complex and heterogeneous, ranging from massive thick sands to highly laminated very thin sand/shale sequences beyond the vertical resolution of microresistivity-imaging tool. Thin bed evaluation based on inversion results are far from reality if one attempts to establish earth-model geometry using conventional threshold technique from static image data that cannot resolve all the beds. When beds are beyond resolution of the tool, use of a single cut off for identification of shale/sand masks the effect of minor lithology and makes the majority of beds appearing as thick and homogeneous. Borehole images on dynamic processing reveal that the formations appearing to be thick and homogeneous on static images, are actually laminated and quite heterogeneous as seen on conventional core photographs. New approach for construction of earth model is based on dynamic processing, in which the image contrast is normalized in a moving window, sharpens the image and makes very thin laminations visible. Sand shale laminations appearing as shaly sands due to vertical averaging effect are converted back to their clean counter parts by applying variable threshold on average pad resistivity curve. Variable thresholds are constrained in such a way that cumulative sand/shale thickness/volume matches with the integrated sand/shale volume curve derived from static image of the tool. Static images had one contrast setting applied to the entire zone in the well and relative changes in rock resistivity have been used for shale volume computation. This makes integrated use of high resolution data where net sand/shale computations from static and dynamic bore hole images are corroborated with each other. Entire procedure is illustrated with an example well where reservoir section is completely cored. Over all conventional threshold approach overestimates net sand by 70% and under estimates porosity by 33% and overestimates water saturation by 18%. Errors in the average reservoir parameters are increasing with the increase of very thin sand laminations. Inversion results with new approach are corroborated with LamCount data as well as laminated shaly sand analysis on electrical anisotropy measurements. The thin bed algorithm based on binary lithology technique identifies the thin sandstone beds and gives a gross sandstone thickness which agrees with the core value to within about 5%. However, thicknesses of individual sand shale laminations generated from enhanced dynamic images are limited to the intrinsic resolution of the image tool. Inversion with new method directly estimates petrophysical properties such as net sand, porosity and water saturation which ensures a consistent petrophysical interpretation. The technique is very robust and can be extended to the evaluation of other fields of the world exhibiting very thin lamination beyond resolution of imaging tool.
机译：精确定义的一组床边界即，高分辨率日志的地球模型基本上需要与一组前进模型结合使用，用于低分辨率测井工具，以执行薄床评估的反转。 Krishna Godavari盆地的深水三级储层通常非常复杂和异质，从大规模的厚砂砂增加到高度层压的非常薄的砂/页岩序列，超出微侦测成像工具的垂直分辨率。如果尝试使用传统阈值技术从无法解析所有床的静态图像数据尝试建立接地模型几何，则基于反转结果的薄床评估远非现实。当褥疮超出该工具时，使用单次切断以识别页岩/砂掩模轻微岩性的效果，使大部分床出现厚且均匀。动态处理上的钻孔图像显示出现在静态图像上的形成厚和均匀，实际上是在传统核心照片上看到的相当异质的。建造地球模型的新方法是基于动态处理，其中图像对比度在移动窗口中归一化，锐化图像并使其变得非常薄的叠片可见。由于平均焊盘电阻率曲线上施加可变阈值，由于垂直平均效应而出现为Shaly Sands的沙子叠层被转换回它们的清洁计数器部件。可变阈值以这样的方式约束，使得累积砂/页岩厚度/体积与来自工具的静态图像的集成砂/页岩体积曲线匹配。静态图像在井中施加到整个区域的一个对比设置，并且岩石电阻率的相对变化已经用于页岩卷计算。这使得综合使用高分辨率数据，其中静态和动态钻孔图像的净砂/页岩计算彼此被证实。用储存部分被完全核心的实例说明了整个过程。在所有常规阈值方法中，净砂升高70％，估计孔隙率为33％，高估水饱和18％。随着非常薄的砂层叠层的增加，平均水库参数的误差正在增加。具有新方法的反演结果与LAMCOUNT数据以及对电各向异性测量的层压谢根砂分析进行了证实。基于二元岩性技术的薄床算法识别薄砂岩床，并提供砂岩厚度，使核心值相当于约5％。然而，从增强的动态图像产生的个体砂页叠层的厚度限于图像工具的内在分辨率。新方法的反转直接估计岩石，孔隙度和水饱和度，其确保了一致的岩石物理解释。该技术非常稳健，可以扩展到对世界其他领域的评估，其呈现出非常薄的层压，超出成像工具的分辨率。

著录项

相似文献

  • 外文文献
  • 中文文献
  • 专利
获取原文

客服邮箱：kefu@zhangqiaokeyan.com

京公网安备：11010802029741号 ICP备案号：京ICP备15016152号-6 六维联合信息科技 (北京) 有限公司©版权所有

  • 客服微信

  • 服务号