Automated Workflow Technology Saves Small Firm Time, Money On Prospects

Information technology helps a small independent exploration firm in Denver compete with companies many times its size.

Samuel Gary Jr. & Associates has cut the cost and time required to generate exploration prospects with personal computer (PC)-based workflow technology integrating geoscience, petrophysical, and land data.

The company, which works mainly in Kansas, North Dakota, Montana, and southern Louisiana, acquired the system in May 1995. Operating in a Windows 95/NT environment, the workflow technology involves GeoGraphix Exploration, an integrated database management, mapping, and analysis system; Prizm, an integrated single and multiwell log analysis system; LeaseMap, an automated lease and ownership mapping component; SeisVision, a fully integrated seismic interpretation and mapping program; and other PC-based industry tools.

"Prior to the acquisition of our workflow technology, we were spending over twice as much money in drafting and reproduction expenses," says Casey Reagan, a geologist with the company.

To Reagan, the main benefit is flexibility. "You can create any type of map you want with limitless layers in a matter of seconds," he says.

Integrating 3D seismic data and geological interpretations involves acquisition of public and proprietary data, which are edited and combined with geology to produce the desired dataset. The new workflow technology speeds transfer of geological data to seismic workstations for interpretation.

"We now have a central database that encompasses the land grid, well and lease information, and seismic data that easily creates datasets used for seismic interpretation and to generate high quality maps for presentation to potential buyers," Reagan says.

Eight Samuel Gary workers regularly use the system.

"We can post wells, generate pay analysis, build lease maps, and make nice cross sections and annotated sections so partners can clearly see what we have done on a particular well," Reagan notes. "And this technology is on everyone's desktop."

How it helps

On a recent prospect in southern Louisiana, Samuel Gary's partner provided Ascii data covering 600 deviated well-bore surveys (Fig. 1 [80,591 bytes]). The workflow system enabled the independent to download the data immediately; before, it would have needed to post the information by hand.

"It would take a draftsman a month to compile this data conventionally," Reagan says. "We loaded, converted, and posted the data in 1 hr."

On a prospect in North Dakota, the company saved what Reagan estimates to be several weeks of time by using the system to combine data from 10 2D seismic lines and 21 wells serving as control points. The project included time and depth-converted maps as well as isothickness.

"We have done some similar projects in other areas which involved more complex depth conversions and the use of digital 2D data," Reagan says.

For one large prospect offer, the Samuel Gary team quickly produced 40 high quality displays for five wells, showing annotated pay zones and important details of the various prospects. The company mailed the color presentations to 20 potential buyers and completed the sale.

The workflow system saves time on nearly every prospect, Reagan says.

On a recent Kansas prospect, a Samuel Gary geologist posted 20 maps, with an average of 700 wells/map, in 1-1/2 days. It would have required 4-5 days to post the same information by hand.

Usually, geologists can load data and have maps the same day.

"The ability to handle various types of data and the flexibility in presenting the data help sell prospects," Reagan notes. "We can point to a given well and immediately get the information we want." The system also acts like a 'think tank,' helping in the development of other ways to present data.

"If I'm told we need a map showing the lease area, zones of interest, and all the basics of a given prospect," Reagan says, "I can generate the map in the morning and make a presentation that same afternoon.

"To accomplish this with traditional tools would be extremely difficult and certainly could not be done with the same quality."

Ideal sequence

Noting that workflow varies from project to project, Reagan says the ideal task sequence follows this pattern:

• Outlining the project.
  First, determine the location and size of a project as well as the anticipated data types to be encountered. The objective is to determine all the possible sources and types of data, including data vendors, public data, and proprietary data.

  Then build a layer-cake model of how the data go together. This model is structured on the idea that the most-raw data occur in the first layer added and that subsequent layers involve more-refined data.

  "In other words, a little planning can prevent some difficult snags in the building of a database," Reagan says.

• Putting the pieces into place.
  Begin loading land-grid, lease, and well information into a central database. Depending on the project, many other types of data such as 2D shot-point locations, 3D survey boundaries, or various types of culture data may be complied at this point.

  "The key here," Reagan says, "is to load and track the data in such a manner as to create the best dataset possible."

• Work displays and quality-checking the data.
  Make sure that all the pieces are loaded and in the right place. Take the time to check that all of the data are loaded correctly and to determine the quality of the various data sources and of the database as a whole.

  Having flexibility to create various types of work displays or base maps is critical to workflow and to quality control of the data.

• Geological and geophysical interpretation.
  Begin to correlate logs or perform tasks such as the building of synthetics to tie the seismic data to the well control. Incorporate other types of data, such as gravity or magnetic data.

  Because interpretation is an iterative process, the central database is very important. It provides a means to simultaneously refine and collect additional data while building an active interpretation.

• Prepping for seismic interpretation.
  Ensure that all available geological data, such as formation tops, fault cuts, and porosity, are loaded into the database and are as complete and accurate as the data allow. Then perform any needed Ascii exports or format conversions to transfer data to the seismic interpretation software.

  This step highlights the value of having a central database. Because the geoscience staff has been able to directly access and build the database from the beginning, the company now has a digital database that can be directly moved to any seismic interpretation software via Ascii or open database-compliant transfer.

• Initial seismic interpretation and fitting of datasets.
  Once the seismic data are in-house, fit and adjust the datasets to begin the process of tying them together. While scanning for prospect leads or confirmation of geological interpretation, also check survey locations and corresponding well locations.

  At this point, the need for geological data may be revised to ensure good seismic interpretation. An example is going back to pick a new formation top that correlates to a key seismic event. This is the beginning of an iterative process that will continue through the life of the project.

• Acceleration of seismic interpretation.
  Now that the seismic data are tied to the geological data, the seismic interpretation can proceed to the stage of detailed mapping of actual prospects. These prospect maps can then be tied back to central data such as land, lease, well, or other data to check for critical cross-correlations.

• Presentation generation.
  After the prospects are mapped in detail, find a way to effectively present a prospect and the key data elements. Mapped horizons and faults can be transferred back to the original database system as xyz data or digitized lines. Once there they can be combined with all of the existing culture, lease, and other geological data to create a series of highly integrated presentations and montages ( Fig. 2 [256,967 bytes], Fig. 3 [140,465 bytes]).

• Prospect sale and drilling.
  The final and ultimate goals are the successful generation of the prospect and subsequent drilling of a discovery. In order for this goal to be reached, a number of things must come together, including interpretation, land, and well planning. Having an integrated system provides an efficient and accurate way to check all the bases. In addition, when discoveries are made, timely evaluation of offset locations is enhanced by the integration of data.

Workflow and integration

Variations from this sequence arise due to problems and time constraints peculiar to specific projects. To Reagan, the key is the degree to which geological and geophysical interpretations are interrelated.

As integration between the two increases, workflow improves and quality of the overall interpretation increases, he says.

And "because petroleum exploration is a continually iterative and expansive process," the central database plays a crucial role in enhancing workflow by both maintaining the data and sharing it with other industry tools.

The system at work

Figs. 2 and 3 show results of the integrated workflow system.

After initial time-mapping of the prospect area, surface slicing through the 3D seismic volume identified an anomaly that appears to be a channel intersecting a complex of faults. The various fault blocks in combination with the stratigraphic bounds of the channel set up a number of prospective traps.

Time and depth surfaces were exported to Geographix, where they were contoured and made ready for display.

The depth structure and leasehold map shows how the structural and stratigraphic components of the prospect sit in relation to the leasehold, the shaded area. The well symbol is the first proposed drilling location.

The time slice of the channel is a Windows metafile exported from the seismic software to illustrate the actual channel anomaly. The 3D perspective map of the corresponding time structure illustrates the structural component of the prospect.

In Fig. 3, the type log demonstrates the existence of analog sand bodies and pay zones.

For a presentation, all the elements would be combined into a montage conveying key components of the prospect.

"The key," says Reagan, "is having a system that not only provides the necessary tools for the scientific development of prospects but is also effective at conveying the interpretation.

"The better the integration of the system, the more effectively this goal can be obtained."

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