The GOM3 Geophysical Add-On currently has three major components. The first is a tool to convert arbitrary seismic or cross-section images to GIS data to display in proper context with other 3-D data such as wells, sand-body reservoirs and paleo observations, while the second component is all of the publicly released seismic data in the Northern Gulf of Mexico. This includes over 13,000 2-D seismic surveys, of which almost 8,000 have the SEG-Y and SEG-PI data included. Additionally, there are 37 released 3D seismic surveys. We have added all -2D navigation lines to the base GOM3 product, as well as the 3-D survey footprints.
The third component is a series gulf-wide salt maps, depth corrected using velocity surveys throughout the Gulf and integrated with other 3-D data.
63 2-D depth sections covering the SS154 field. Salt dome in center surrounded by GOM3 reservoir models and wells.
GOM3 Seismic Conversion Tool
The GOM3 Seismic Tool integrates proprietary seismic data with existing GOM3 3D GIS data. The tool allows users to place seismic data into a 3D scene alongside GOM3 GIS data as well as any other proprietary GIS data. In addition, the tool can be used to place any vertical cross section (stratigraphic, geochemical, log-derived, etc.) into a 3D scene. The tool handles an almost unlimited number of coordinate systems and can be used outside of the GOM.
Cropping a seismic depth image before it is placed in a 3-D scene.
The GOM3 Seismic Tool reads in data from a navigation file such as SEG-P1, but also simple comma-delimited text files. For instance, a vertical cross-section from any of a variety of sources can be integrated with other data simply by knowing its coordinates and depth as shown below.
Looking down two different cross-sections that have been placed into a 3-D scene. The image at left extends between two points while the image at right contains many points of navigation.
Much more dramatic than a well-organized collection of data files, we succeeded in inserting the ~8,000 lines with SEG-Y into the 3D component of GOM3. Presently, you can click on a field outline in 2D GOM3 and choose to display the field in 3D with wells, comps, paleo, reservoirs and facilities. Now, with the GOM3 Geophysical Add-On, you can also add all of the released seismic lines that intersect the field. These have been converted from time to depth using a two-part local approximation of velocity in the neighborhood of the field. While this type of batch local time-to-depth conversion, based on average properties, is not the detailed analysis that a geophysicist would provide, our method has produced about 250,000 line-miles of seismic depth sections that clearly place our existing 3D models of over 1,000 fields in their geologic contexts. Some fields have more than 60 crossing lines; even fields in deep water typically have a half-dozen or more lines available for display. In addition to depth sections in 3D GOM3, we have made preview images of the time-sections of all 2-D lines. Subscribers to the GOM3 Geophysical Add-On will receive regular updates to the data as BOEM/BSEE releases more. As with all other components of GOM3 over the last 17 years, we will be constantly upgrading the functionality of the GOM3 Geophysical Add-On.
Mars-Ursa complex: seismic, wells and reservoirs, colored
by pressure gradient (0.58-0.83 psi/ft, blue to red).
We think our GOM3 Geophysical Add-On is a major breakthrough in 3D GIS and in field to basin-level petroleum geology, as we know of no other application that allows you to browse and study seismic for an entire basin. These technologies will be a major focus for GOM3 research and development and we invite you to be in at the beginning, so you can get the value now and help guide us in building on this major foundation.
Nansen Field (EB602): seismic, wells, reservoirs & surfaces estimated for Disco. brouweri (shallow) & Disco. tamalis.
Top of Salt
The doors opened for new research and valuable results with the SEG-Y records for so many thousands of 2D seismic lines across the Gulf. Covering a whole basin, this is a unique collection of seismic data and invited us to analyze all of the lines collectively using machine-learning techniques. For a basin in which salt has played such a central role in forming oil and gas fields, the first priority was discriminating salt on all of the lines and producing a basin-wide top of salt map.
No geologic variable in the GOM has played a greater role than salt in the accumulation of oil and gas. Over half the discovered oil (~12 billion bbls) and a third of the gas (66 TCF) were found in traps directly related to salt. A large share of the remainder was in faults and anticlines formed indirectly by salt or was discovered under salt canopies on the slope.
The top of salt at Ship Shoal 154.
The last 5 years of the geophysical literature reports a few experiments in machine-identification of salt but these projects typically include only a few lines as examples and employed “supervised learning.” Supervision means the algorithms required an input set of salt/no-salt examples prepared in advance by geophysicists. By contrast, we applied our technique to 8,000 lines and employed “unsupervised learning,” meaning that our algorithms were not given a set of examples what is and isn’t salt.
Using these salt boundaries within the images, the top of salt was found and mapped to create a basin-wide top of salt map for most of the western and central regions of the Gulf of Mexico. The first-generation Gulf-wide top of salt map is included in the new Geophysical Add-On in three ways: as a map in time, in depth and as 3-D surfaces introduced into the 3-D field models of GOM3, providing greater context to the reservoir and well data.
Depth to the top of salt in central Eugene Island and Ship Shoal areas.
Digital Well Logs
The BSEE has released raw digital logs from 2004 on and will now release files on a regular schedule. BSEE's (MMS's) files before 2004 were destroyed during Hurricane Katrina. Earth Science Associates is maintaining the existing files in a manner similar to the well log images, making them accessible by choosing a well in various platforms/applications and giving the files more helpful names for organization.
The initial set covers about 11,000 files on nearly 5,000 wells, well distributed throughout the Gulf.
Wells with digital well logs available.
The digital logs are available within both the standard GOM3 and GOMsmart. In GOMsmart, they are accessible by clicking a well in the main page, custom report previews or the GOMsmart maps. In GOM3, clicking on a well within a map or 3-D scene links to the well logs.
Digital logs are listed first in green when viewing the well logs page.
GOM3 Geophysical Add-On includes:
Seismic Conversion Tool: Wizard to load arbitrary vertical seismic slices or cross-section images into scenes of 3-D vector data
Seismic Data: 15,161 2-D seismic lines of which 10,056 have SEG-Y and SEG-P1 data 114 3-D surveys with SEG-Y data Regular updates of all newly released data
Top of Salt: Gulf-wide top of salt map and individual surfaces of the top of salt for each field, displayable in 3-D
Digital Well Logs: All released raw, digital logs (LAS, DLIS, LIS, etc.), organized and accessed by choosing a well in map, 3-D scene or GOMsmart pages
GOM3 functionality: All lines and surveys mapped in 2D Previews of all 2-D time sections 7,645 2-D SEG-Y lines can be added by field as depth sections in GOM3 -3D