Conventional seismic processing methods group traces from different source-receiver pairs that share a common midpoint into a gather that is stacked. This allows the effects of different source-receiver offsets and azimuths to mix, often to the detriment of image quality and causing the loss of valuable information about changes in seismic attributes that relate to reservoir properties like fracturing and structure.
Processing based on offset vector tiles (OVT) works differently. Offset vector tiles are single-fold subsets of an orthogonal survey and can be extracted for near, mid- and far offsets. OVT-sorted data groups like offsets and azimuths, thereby optimally preserving offset and azimuth integrity. Sorting and processing the data in this manner allows for robust methods of interpolating for missed shots, statics processing, noise attenuation, data migration and AVO/AVD analysis.
The denser the orthogonal surface sampling, the better OVT techniques work. With conventional wide-azimuth acquisition methods, sampling densities are not high enough to effectively employ OVT-based methods.
FireFly supports acquisition densities that are high enough to make OVT possible, allowing oil & gas companies to capture 1,000 fold seismic data, populate cross-spreads for noise removal, compensate for anisotropy using PreSTM, and preserve reliable offset and azimuth attributes for reservoir properties.
The FireFly land imaging methodology – combining cutting-edge survey design, acquisition hardware, and OVT data processing – will be crucial in pushing toward the goal of full-sampling. And capturing higher utility, higher resolution subsurface images that reduce the risk and cost of hydrocarbon exploration.
