Challenge:
Large volumes of allochthonous salt have moved and pierced through large sedimentary sequences in the Gulf of Mexico basin. Halokinetics have caused significant deformation and created one of the more structurally complex areas on Earth. Hundreds of mini basins have formed due to salt evacuation. Steep rock beds, areas of over pressure, and stress rotation around salt domes are also common. Imaging around and below the salt is a challenge, but necessary to understand trap, trap size risk, migration pathways, source rock maturity, and change among other petroleum system elements.
Current Traditional Workflow:
Interpretation begins on stacked data, but interpreters loose almost 90 percent of the crucial information present in pre-stacked data. Stacked data has subtle amplitude variations that can easily be missed. Additionally, variation of amplitude with offsets are not be detected. Before a geoscientist even starts their interpretation, the data already contains bias information from the velocity model.
Stacked datasets are often created by external vendors with little input from the final user. Companies are charged for any additional partial stack, and those partial stacks are created on pre-set angles and offsets without a high level of quality control. Crucial time can be lost waiting for 3D partial stacks from a vendor. If a dataset is too large for the interpretation software, the user can decimate the data and/or subset the area in smaller sub-volumes.
Bluware Deep Learning Workflow:
The combination of anisotropy, high deformation, and velocity variations can make size estimation a challenge. Bluware’s velocity modeling, combined with real-time stacking functionality, allows interpreters to easily create multiple case scenarios. Since the velocity data can be adjusted on-the-fly, different velocities can be used to create multiple 3D stacks.
Variable azimuths are often used for proper illumination below salt. Bluware WAZ real-time stacking functionality can help the interpreter create more fit-for-purpose stacks. Working with multiple hypotheses makes it possible to have a distribution of trap risks and sizes.
Manually interpreting multiple volumes is a challenge, but now with Bluware deep learning technology, the interpretation process can be accelerated 20 to 30 times allowing for time to interpret multiple seismic volumes.
Amplitude variation with offset (AVO) plays are common in the region, most of those are already being drilled in the United States, but remain to be drilled in the Mexican portion of the Gulf of Mexico. Bluware’s pre-stack functionality is particularly powerful to work on these amplitude plays. Partial stacks, gather conditioning, and AVO on-the-fly can help accelerate identification of these prospects.