OIL GEOLOGISTS DISCUSS BEND SERIES FOURTH ANNUAL CONVENTION OF AMERICAN ASSOCIATION MEETS IN DALLAS. PROMINENT MEN HERE Dr. David White of U. S. Geological Survey and Prof. Schuchert of Yale Are Among Speakers. The bend series that produces the oil in the North Central Texas field held the attention of the two hundred or more petroleum geologists who met yesterday in this city for the fourth annual session of the American Association of Petroleum Geologists. The meeting took on the aspect of the local situation. But it was as much as the North and North Central Texas oil fields are the most interesting feature of the petroleum business just now, this was natural and proper. It developed that geologists are not of one accord as to the great plunging anti cline, that is known as the bend series and that the so-called black limestone that is the bend formation, is very mostly calcareous shale; and one geolo gist advanced the theory that the true thickness of the so-called bend lime tone depended on the fact that drilling got better pay for drilling in limestone that is found at great depths than they get for drilling in other formations--so the logs of this wells show lots of limestone. The theory was advanced that logs of wells, according to drillers' reports, not geologists', are what proposes. Paleontologists Appear. Then it was that the paleontologists had a saying and the geologists decided that fossils alone are the true index and the only sure way of correlating structures. Dr. David White of the United States Geological Survey, and Professor Charles Schuchert of Yale made the point in this unsought that was made by the paleon tologists, and may it very well be said, fossils alone can be identified even when drilled into infinitely small frag cments, alone can determine the age and character- of a structure that is being drilled into "Age cannot be known by dips upon mythology," asked Professor Schu cbert. "You must know these things on their color. Let me make a plea for fossils. You need the aid of paleontologists. Surface Reflections. The subject of subsurface structure as re- lated to subsurface structure was also interestingly discussed, a paper by Wal ter F. Pratt, vice president Gulf Oil and Refining Company, on this subject lead- ing to considerable debate and strong emphasis of opinions. It seemed to be the opinion that the anticline indicated in the North and North Central Texas fields might well be used as a guide to point the way to pools of oil deep underneath the surface. Mr. Pratt did not go up to the whole theory of the bend being a great plunging anticline, but he seemed to believe that the structure probably very distinct in the southern part and probably more or less dips to the northward it also flattens out into a considerable syncline. He pointed to the minor folds and formations on the bend from which the petroleum had went into detail as to the results of tests and correlation of strata that have been attempted in different Paleozoic eras. He also discussed the relation be- tween the anticline and the syncline and concluded that so far as development has proceeded, it has not been possible to come from the wells located on the high center points upon the bend. He also concluded that the problems of the geolo gist in North Texas are research prob- lems and that accurate plans will be re- quired in order to get the best results. Mr. Robert L. Hill of Houston, who dis- cussed the theory of the plunging anticline of the bend, pointed out that he stressed the fact that the arch may flatten out into a syncline on the north. He also took issue with the theory that sur- face indications are not a good index to subsurface structure. He said the oil fields in hidden strata were much more the drillings in Brown County as show- ing indications of surface structures applied to the subsurface formations with ac- curacy. Age of the Bend. The question as to what period the bend belongs to, whether it has not been settled. That the bend is made up in part at least below the level of the upper Mississippian is the most popular theory. And it was put forward by Dr. W. F. Cummings of Houston, who is the patriarch of the profession, that he put forward this theory about 40 years ago and that he was not considering any member of the series that is now considered to be a part of the Permian. He defended his theory that the whole series is Pennsylvanian and at- tempted to show this by paleontological researches. It was pointed out by Professor Charles Hutchins, Rice University, that the underlying Ellenberger lime- tone is the only good place possible to correlate, and then he raised a ques- tion as to whether the so-called Ellen- berger limestone belonged in the north. It was a lively and wit-sharpening dis- cussion that left the petroleum geologists had over the bend, the producing forma- tion is now in oil fields. Meeting Opens With Welcome, Alexander Deussen of Houston, presi-