Abstract: This article introduces the world’s largest 3D DAS-VSP data acquisition and imaging processing project to date. In 2002, ADNOC carried out ultra-high-density 3D OBN data acquisition in the Zakum Oilfield off the shore of Abu Dhabi, and at the same time used the armored fiber optic cables strapped on the tubing of 13 high-production oil wells and water injection wells in the operation area to acquire 3D OBN and DAS-VSP data simultaneously. Of those wells, six wells of high-density 3D DAS-VSP data acquisition have been completed off the shore of the North Island, with an area of 150 square kilometers source carpet and an air gun density of 25 meters × 25 meters. The number of collected shots totaled more than 2.4 million. Seven wells of high-density 3D DAS-VSP data acquisition have been completed off the shore of the Central Island, with an area of 160 square kilometers source carpet and an air gun density of 25 meters × 25 meters. The number of collected shots totaled more than 2.8 million. The latest uDAS2.3 instrument was adopted as the acceptance instrument for real-time acquisition, processing and storage of the data. The level spacing of the original data in the well is 1 meter, and the sampling rate is 1 ms. For the blended acquired 3D DAS-VSP data, the most advanced deblended algorithm based on sparse inversion was used for preprocessing to obtain the original record with high signal-to-noise ratio. Then, the abnormal amplitude noise suppression and multiple wave suppression were conducted by using time-varying deconvolution or Tau-p domain deconvolution. The anisotropic velocity modeling was carried out by combining the first arrival tomography inversion and joint domain full waveform inversion (JDFWI). Finally, the multi-well joint upgoing wave, downgoing wave and multiple wave migration processing was performed to provide an accurate 3D DAS-VSP data imaging of the structure and fluid prediction of the reservoir around the well and guide the layout drilling of horizontal production wells with all-round radial pattern in the operational area.

Key words: DAS-VSP; ocean bottom node (OBN); joint domain full waveform inversion (JDFWI); least squares reverse time migration (LSRTM); joint acquisition; multiple imaging; tomographic imaging

摘要： 文章介绍了迄今为止世界最大规模的多井三维DAS-VSP 数据的成像处理方法研究。2022年，ADNOC公司在阿布扎比近海Zakum油田实施了超高密度三维OBN 数据采集，同时利用工区内13口高产油井或注水井管柱外固定的铠装光缆同步接收三维DAS-VSP 数据。其中北岛6口井，气枪震源覆盖面积超150km2，气枪密度为25m×25m，采集总炮数达240余万炮；中央岛7口井，气枪震源覆盖面积达160km2，气枪总采集炮数达280余万炮。接收端仪器采用最先进的uDAS2.3仪器进行数据实时采集、解调和存储，井下接收级间距1m，采样率1ms。气枪震源采用混采激发，接收数据段显示明显的混炮痕迹。针对混采的DAS-VSP共炮集数据，采用先进的基于稀疏反演的解混算法进行解混预处理，获得高信噪比的原始记录。在此基础上进行异常振幅噪声压制处理，并利用时变反褶积或Tau-P域反褶积进行多次波压制，综合初至层析反演和联合域全波形反演（JDFWI）进行各向异性速度建模，最后实施多井联合上行波、下行波和多次波偏移成像处理，为甲方提供了准确的VSP数据采集井周围储层构造成像信息，为工区内全方位放射状分布的水平生产井的布设和钻进提供技术支撑。

关键词: DAS-VSP；OBN；联合域全波形反演；最小二乘逆时偏移；井-海联采；多次波成像；层析成像