基于模型分析的OBC采集方向选择

海上油气勘探中应用常规拖缆方式采集数据的方位角相对较窄，难以满足复杂构造的勘探需求；而采用海底电缆方式可通过调整缆数和缆间距实现宽方位角数据采集。本文从地层建模出发，对层位解释成果数据进行Delaunay剖分，求解剖分构建的三角面空间坐标和地质产状等信息；对这些信息进行统计分析，得到勘探区构造走向、倾向和倾角等数据；据此设计地震勘探主采集方向，调整缆数和缆间距参数，拓展方位角信息，使其兼顾主构造方向和次级构造方向的数据采集，以进一步提高复杂构造的成像质量。

OBC acquisition direction selection based on model analysis

The acquisition azimuth of conventional streamer seismic surveys is relatively narrow, and is unsuitable for complex structure areas. But for OBC survey, wide-azimuth data acquisition can be achieved by selecting the number of cables and a cable spacing. In this paper, based on stratigraphic model we first conduct the depth domain Delaunay triangulation on interpreted stratigraphic data, calculate split triangles spatial coordinates, and acquire geological information. Then we obtain structure trend, tendency and dips of the exploration area using statistical analysis, and build a geological model. Finally based on this model we select appropriately the number of cables and a cable spacing in OBC acquisition geometry design in order to get wider azimuth and better images of complex structures.