Think About It: New Ideas Equal New Success

Some older members of AAPG may remember when geologists, geophysicists and engineers worked under separate supervision and in separate departments in oil and gas companies. It may be hard for some of you to believe, but in many companies there literally was a geology department, a geophysics department and an engineering department.

Why were the disciplines separated? I really don’t know.

Probably, though, it was due primarily to the conceived value of integrated confidential data. I also suspect unhealthy competition, as well as some misguided mistrust, between the different disciplines contributed to the limited sharing of data within a company. By separating the disciplines access to information was carefully controlled, and only upper level management could see the big picture.

Another reason might be educational background. My dad, who also is a geologist and longtime AAPG member, reminded me that geologists, geophysicists and engineers used to be educated separately.

Physicists were hired to be geophysicists, he said. They generally didn’t have any geological course work. And engineers were not required to take any geological courses before they were hired to be petroleum engineers. As a result, it was natural to separate the disciplines into departments.

One older geologist/friend who worked for a major oil company told me that in his era he had to get special permission to look at seismic (2-D) sections, for which specific security was in place to handle their restricted use by geologists – usually under the watchful eye of a senior geophysicist.

My first job was with Cities Service Oil Company. Geologists, geophysicists and engineers were all in our separate departments, and even when we were all working on the same project we worked separately. We geologists generated prospects; they then were vetted for economics by engineers and “shot-out” seismically by the geophysicists.

While I was working at Cities Service, however, things began to change between geologists and geophysicists. The big catalyst seemed to be the publication in 1977 of AAPG Memoir 26, “Seismic Stratigraphy: Applications to Hydrocarbon Exploration.”

At that point geologists began to realize that seismic sections could show more than anticlines and synclines.

In Memoir 26, Peter Vail and his colleagues at Exxon Production Research postulated that seismic reflections are time synchronous and do not necessarily follow lithologic boundaries.

This controversial statement created much debate between geologists and geophysicists – and forced us to begin a dialog about exactly what seismic reflections represent geologically.


You might think it obvious that the two societies that represent petroleum geologists and geophysicists, AAPG and Society of Exploration Geophysicists (SEG), would get together often and have many joint projects where we could exchange ideas. However, there have been very few.

Those few, however, have been notable.

SEG started in 1930 as Society of Economic Geophysicists. In 1932, they changed the name to Society of Petroleum Geophysicists and became affiliated with AAPG, holding joint meetings with AAPG for more than 20 years.

In 1937, they changed their name to what it has been since then: the Society of Exploration Geophysicists.

In 1972, AAPG and SEG co-published Memoir 16, “Stratigraphic Oil and Gas Fields.” Twenty-four years later, in 1986, AAPG and SEG co-published Memoir 42, “Interpretation of Three Dimensional Seismic Data,” written by AAPG member Alistair Brown. It has been a tremendous success and is now in the seventh edition.

This year SEG and AAPG are joint partners in two potentially very significant new projects:

One, initiated by SEG, is a new journal to be called, INTERPRETATION. As described in the March EXPLORER , SEG and AAPG will share editorial responsibilities and expenses for this publication.

INTERPRETATION will be less technical than SEG’s Journal of Geophysics and more technical, in terms of geophysics, than the AAPG BULLETIN.

The other huge new project was initiated by AAPG through an idea generated by AAPG’s former executive director, Rick Fritz, about a new conference that brings AAPG back together with SEG for the first time for joint involvement in a meeting since the 1950s.

The meeting will be called the Unconventional Resources Technology Conference, or URTeC for short.

URTeC, however, is being started not just by SEG and AAPG but also in partnership with the Society of Petroleum Engineers (SPE) – and this new, science-driven event marks the first time all three societies have been in such partnership.

The first URTeC will be held Aug. 12-14 in Denver.

Finally, geologists, geophysicists and engineers are formally getting together to share ideas concerning the exploration for and development of unconventional reservoirs.

Why was URTeC created? It is the understandable product of blending the disciplines for more effective exploration and development of unconventional resource plays. For example, engineers realize that an understanding of geological variation of shale gas reservoirs leads to better completion designs and, therefore, higher initial flow rates and higher EURs.


I sincerely hope all of this is just the beginning. Previous AAPG presidents like Dick Bishop have dreamed of the benefits of inter-society cooperation. One can only imagine what synergism between AAPG, SEG and SPE will create.

At first we were hesitant to trust each other, but we realized the more we combined our skills the better we were at finding oil and gas.

If we all forget our self-interests and work together we only have one place to go – onward and upward!

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President's Column

President's Column - Ted Beaumont

Edward A. "Ted" Beaumont, AAPG President (2012-13), is an independent consultant with Cimarex Energy.

President's Column

AAPG Presidents offer thoughts and information about their experiences for the Association. 

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See Also: Bulletin Article

Estimation of the dimensions of fluvial geobodies from core data is a notoriously difficult problem in reservoir modeling. To try and improve such estimates and, hence, reduce uncertainty in geomodels, data on dunes, unit bars, cross-bar channels, and compound bars and their associated deposits are presented herein from the sand-bed braided South Saskatchewan River, Canada. These data are used to test models that relate the scale of the formative bed forms to the dimensions of the preserved deposits and, therefore, provide an insight as to how such deposits may be preserved over geologic time. The preservation of bed-form geometry is quantified by comparing the alluvial architecture above and below the maximum erosion depth of the modern channel deposits. This comparison shows that there is no significant difference in the mean set thickness of dune cross-strata above and below the basal erosion surface of the contemporary channel, thus suggesting that dimensional relationships between dune deposits and the formative bed-form dimensions are likely to be valid from both recent and older deposits.

The data show that estimates of mean bankfull flow depth derived from dune, unit bar, and cross-bar channel deposits are all very similar. Thus, the use of all these metrics together can provide a useful check that all components and scales of the alluvial architecture have been identified correctly when building reservoir models. The data also highlight several practical issues with identifying and applying data relating to cross-strata. For example, the deposits of unit bars were found to be severely truncated in length and width, with only approximately 10% of the mean bar-form length remaining, and thus making identification in section difficult. For similar reasons, the deposits of compound bars were found to be especially difficult to recognize, and hence, estimates of channel depth based on this method may be problematic. Where only core data are available (i.e., no outcrop data exist), formative flow depths are suggested to be best reconstructed using cross-strata formed by dunes. However, theoretical relationships between the distribution of set thicknesses and formative dune height are found to result in slight overestimates of the latter and, hence, mean bankfull flow depths derived from these measurements.

This article illustrates that the preservation of fluvial cross-strata and, thus, the paleohydraulic inferences that can be drawn from them, are a function of the ratio of the size and migration rate of bed forms and the time scale of aggradation and channel migration. These factors must thus be considered when deciding on appropriate length:thickness ratios for the purposes of object-based modeling in reservoir characterization.

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Desktop /Portals/0/PackFlashItemImages/WebReady/ace2015-ft-11-hero.jpg?width=50&h=50&mode=crop&anchor=middlecenter&quality=90amp;encoder=freeimage&progressive=true 14702 Field Seminar