A survey taken of nearly 300 AAPG members in five U.S. cities by the AAPG Reservoir Development Committee may surprise readers about how much effort by geoscientists is going toward improving recovery from already producing fields.
In a recent survey, 57 percent of the respondents listed reservoir development as a significant part of their efforts, while 32 percent focus entirely on reservoir development.
As expected in the more densely drilled parts of the country, there is more emphasis on reservoir development -- nearly 74 percent in Oklahoma City compared to 45 percent in Houston.
Respondents were about equally split among majors/large independents, producers/small independents and consultants. Geoscientists whose primary work activity is reservoir development vary from 50 percent (majors/large independents) to 68 percent (independent producers).
In the past there has been the perception among some managers and geoscientists that exploration requires more savvy than reservoir development. However, in all of the cities surveyed geoscientists believe that reservoir development is at least as important as exploration.
We are all painfully aware that the environment of the geologist has changed a great deal in recent years. Two-thirds of the respondents now work in multidisciplinary teams.
As expected, well logs are still the primary tool of geologists (88 percent), however, computer applications form an ever increasing part of their work. Computers are utilized by respondents for mapping (62 percent), seismic interpretation (52 percent), cross-section generation (41 percent) and log analysis (39 percent).
Three-D seismic and horizontal drilling technologies are used by 50 percent and 43 percent, respectively.
> What do these figures mean to the geoscientist of the 21st century?
It means that if you work as a geologist you more than likely will spend a significant amount of time doing reservoir development and interacting on a daily basis with engineers, petrophysicists and geophysicists. Among these disciplines, the geologist should be the best equipped to integrate the data in order to determine the best economic outcome.
As stated recently by Gustavo Inicarte of Petroleos de Venezuela S.A. and current president of SPE, "we talk about, and move more and more toward, an asset-management approach that requires multidisciplinary teams. However, for one reason or another, when it comes time to do the work and really integrate, we always hesitate. Why? I'm sure each of us has a very particular ... answer to that question."
Veteran geologists know that it was common for companies to separate the geologists, geophysicists and engineers into their "own" working environment, sometimes going so far as to have them on separate floors of a building. This physical separation often resulted in the development of three different scenarios for the same reservoir development project -- and when they met to discuss future plans there was, to say the least, some disharmony.
Today's multidisciplinary team approach can work out the different points of view through daily discussions to develop a common model, or at least narrow the range of working scenarios.
> How does the geologist fit into the team?
Clearly, today's geologist has to be much more quantative than earlier generations. Why? Because on most moderate- to large-size projects a reservoir simulation involving geostatistics is used to asses risk, the scale of development, potential profitability and areas of insufficient knowledge. The more successful models include significant deterministic input as well as stochastic simulations. The "Shared Earth Model" as it has been called by European reservoir description teams (Samson,et.al), includes structural, sedimentological, stratigraphic, petrophysical and production data.
A major advantages of such a model is that once developed, the model can be updated fairly easily as additional wells are drilled and new data is obtained.
Many of the techniques used in reservoir development are also applicable in exploration plays, so the development geologist of today should be well qualified to move into an exploration team and use the reservoir development technologies of tomorrow.