Pore Pressure Prediction Maps are now available in GOM3 under the Geology/Geophysics tab. Data for the analysis were collected from GOM3 on mud weight (Map Layers->Wells->Well Activity Report Data) and sand initial pressure gradient (Map Layers->Hydrocarbon Accumulations->Sands). The data for each variable were divided into 1000-ft intervals below two datums: mud line and mean sea level. All data points that fell in a certain interval (e.g., 8,500-9,500 feet below mud line) were used to estimate a grid across the whole study using the Ordinary Kriging algorithm in the Geostatistical Analyst extension in ArcGIS 10.
For each depth interval and both mud weight or pressure gradient, there is a pair of maps: one of the estimated mean and the other that shows the variance of the estimated mean (i.e., the kriging standard error or KSE). The mean maps for both variables share a common legend to allow comparison.
The user may choose between clipped or unclipped versions of these grids. The unclipped maps have a standard rectangular extent that covers the Central and Western GOM. The clipped versions of the maps have been blanked based on the statistical confidence in each of the estimated mean mud weight and pressure gradient maps. The portion of the maps that remain after the clipping meets a minimum threshold of certainty in the information being mapped.
These maps were the product of a joint research project conducted last summer between ESA and the graduate applied mathematics program at California State University Fullerton.
Estimated Pore Pressure at 7,500-8,500 feet below mud line.
Two new columns are available in the leases dataset. The first, MROV, is also available in the Lease Bid History table. The second, Last Past Lease Flag, indicates the last former lease of a block. This also made it possible to update the open blocks shapefile to more accurately list the status of each open block.
Owner assignment end dates have been calculated. This data is not released by BOEM and the calculations are subject to error if an ownership group does not add to 100%. This new data should however make it far easier to determine if a company owned a lease in a particular period of time.
Blocks where ExxonMobil had record title interest on March 14, 2009.
For a list of past newsletters, click here.