高密度二维地震采集技术在S西部应用研究

工区表层地震地质条件复杂。近地表多为流沙,干燥、疏松,能量衰减快;深层地震地质条件为砂泥岩薄互层,反射能量较弱。区域目的层储层薄,在纵横向上物性变化大。总体工区资料品质受潜水面影响较大,古河道和古湖盆发育区低降速层较厚,可达100m以上,资料视主频极低;为获取品质良好的地震资料,在该区进行了高密度二维地震资料采集技术研究,采集的资料品质较以往有了较大的提高。主要目标反射层能连续追踪、层间反射内幕清晰,资料的频宽提高了10Hz左右,能满足岩性解释的需要,提高了天然气勘探的精确度。

Research of 2D High-density Seismic Acquisition Technology in Western S Project

The seismogeological conditions are very complex in the surface of work area.There are mainly drifting sands and dry loose feature with energy decaying quickly in the near surface;The seismogeological conditions are sand-shale interbedding and weak energy of reflection in the deep layers.Target reservoir of this area is thin and variable physical property up in the vertical and horizontal.Under the influence of water,data quality in the survey is not satisfactory.The low velocity layer in the areas of old channel and fossil lake basin is up to above 100m,so the apparent basic frequency of data is very low.In order to collect seismic data with good quality,we do a research about 2D high-density seismic acquisition technique for this area,and have good outcome.The main reflection layers can be continuously tracked,reflection information between the layers is clear,and data bandwidth improves 10Hz,which can meet the needs for lithologic interpretation.This research improves the accuracy in natural gas exploration.