Study on high-precision time-depth projection method under complex terrain conditions

Bian, Li’en (China National Offshore Oil Corporation (CNOOC) Ltd. Tianjin Branch) | Zhang, Jingsi (China National Offshore Oil Corporation (CNOOC) Ltd. Tianjin Branch) | Xu, Jialiang (China National Offshore Oil Corporation (CNOOC) Ltd. Tianjin Branch) | Yang, Wei (China National Offshore Oil Corporation (CNOOC) Ltd. Tianjin Branch) | Yu, Qian (China National Offshore Oil Corporation (CNOOC) Ltd. Tianjin Branch)

OnePetro 

A good time-depth projection method plays an important role in improving the accuracy of depth prediction. When designing a new well, we need a time-depth relationship to predict the depth of the target layer and then design the well trajectory. The traditional approach is to directly use the time-depth relationship of adjacent well. However, as the target reservoir becomes more and more complex, the lateral change of the formation velocity is more and more large. In this case, the traditional approach is difficult to meet the research needs. This study proposed a new high precision time-depth projection method, which firstly establishes a high precision space-varying velocity model under the constraint of geological structure, then extracts the average velocity at each point of the well trajectory, and finally creates a high precision time-depth relationship based on MD (Measured Depth) of well trajectory which is different from the traditional time-depth relationship based on TVD (True Vertical Depth). The application result of real seismic data demonstrates the effectiveness of our method.

Presentation Date: Monday, October 15, 2018

Start Time: 1:50:00 PM

Location: 210A (Anaheim Convention Center)

Presentation Type: Oral