Tight Rope Research Articles

Bar-Mar Field, The Tricky Devonian: ABSTRACT

What originated as the Fusselman play in southern Crane County developed into a 4-million-barrel oil field in the Devonian, an 8-billion-cubic-foot Clear Fork gas field, a 1-million-barrel Tubb field, and two Fusselman dry holes. The areal extent of this field has not been developed and is not fully known because of the large amount of acreage held by production and controlled by the major oil companies. The original geological interpretation suggested possible oil production in the Fusselman updip from a dry hole that recovered 25 barrels of sulfur water per hour on a drill-stem test. The porosity and permeability indicated from this drill-stem test suggested a fairly sizable reservoir at a relatively shallow depth of 5,400 feet. This information, in conjunction with sufficient dry-hole money and a fairly sizable acreage position for Crane County, encouraged the writer and his partner to drill the prospect. It took 1 month to sell the deal and 13 investors before sufficient funds were available to spud the well. The Devonian tripolitic chert contains one of the highest recoverable oil reserves in the Permian basin. This chalky reservoir is difficult to explore and develop. The number of dry holes are many, but the recoverable oil justifies the risk involved. The apparent trend in this wedge-edge, scarp, or tight rope can be noted along northern Crockett, southern Crane, and northern Pecos Counties. These fields which are productive from the Devonian appear to be related directly to the Fort Stockton High. The numerous adjustment or radial faults that are present along the flanks of this major structural feature are believed to be the cause of this oil accumulation. The many fields along this trend exhibit different modes of hydrocarbon accumulation. These fields in Devonian strata produce in re-entrants, grabens, and wedge-edges of tripolitic chert. The Bar-Mar field appears to be productive in a graben. While developing this field, several additional oil and gas pays were discovered; however, the major part of the Devonian production eluded the discoverer. Although it is always the dream of the independent End_Page 166------------------------------ to own an entire oil field, industry still needs the wildcatter and the independent to find the oil. This is exemplified further by the fact that, in order to find oil, one must drill wells. For several years it has been the writer's philosophy that the amount of oil discovered is directly proportional to the exposure or number of wells drilled, providing that the wells are drilled in oil country. The Bar-Mar field is a case in point. End_of_Article - Last_Page 167------------

Motor localisation in the brain of the gibbon, correlated with a histological examination

Motor localisation in the Gibbon has not been hitherto determined experimentally, probably owing to the difficulty of obtaining a suitable animal. It appeared to be desirable, therefore, to see whether the habits and mode of life of this animal could be correlated with an increased development of the motor cortex. One of us (F. W. M.) had some years ago, by a comparative study of the convolutional pattern of the brains of Lemurs and Apes, made the following deduction: “The remarkable use this animal makes of its arms and hands can be correlated with a remarkable expansion of the cortex in the precentral region, as shown by the development of a broad gyrus extending from the middle of the precentral region to form the second frontal convolution. Now if we turn to the Ape’s brain (Maeacus), and see what the effect of this development would be, we observe that it would push forwards and downwards that portion of the cortex which on stimulation gives rise to movement of the head and eyes, particularly that which gives rise to eye movements, etc.” Figures were shown to indicate that the sulcus arcuatus would be pushed down to join the sulcus rectus. The following experiments by stimulation, correlated with a complete histological examination of the cortex in front of the central sulcus, have confirmed this deduction. The animal used for the experiments was a male and black in colour; it was remarkably agile; when standing or running on the ground it maintained almost an erect posture, using its long arms to balance itself very much as a man would walk on a tight rope with a- balancing-pole. It was kept for some days before the experiment in the animal room of the Physiological Laboratory, Liverpool, and it was frequently heard to utter vocal sounds of very varying pitch and quality. Thus it could imitate the shrill high-pitched whistles of the guinea-pig and the relatively low-pitched bark of the dog. A short account of the larynx of this animal will be made the subject of a future publication.