GEOPHYSICS—FULL PARTNER

Geophysics ◽  
1957 ◽  
Vol 22 (2) ◽  
pp. 225-232
Author(s):  
Morgan J. Davis

The advent of exploration geophysics in the United States was in late 1922 when torsion balances were brought over to the United States from Germany by both the Roxana (the predecessor of Shell) and the Amerada Petroleum Corporation. The first survey in the Gulf Coast of Texas was at Spindletop in December, 1922, under the direction of Donald C. Barton, who later and at the time of his death in 1939 was Humble’s chief research geologist. It was Donald Barton’s idea that the known shallow piercement‐type salt dome at Spindletop would furnish a testing ground for this new method. It should be recorded that an excellent anomaly was found in this survey. Discouraging results followed, however, as other known structures were found to give no significant anomaly, and in other instances where anomalous areas were outlined they were condemned by the drilling of exploratory wells. In March, 1924—about a year and a half later—however, an outstanding anomaly was found in the Nash area, Fort Bend County, Texas. In November of that same year dome material was found by the drill, and the discovery of the Nash Dome was a reality. It was not until January 3, 1926, though, that oil was found on the flank of the dome, and this is probably the first oil found as a result of the use of geophysical methods in the United States.

Geophysics ◽  
1953 ◽  
Vol 18 (1) ◽  
pp. 188-200
Author(s):  
Antonio Garcia Rojas

Since 1940 Mexico has increased exploration work in search of new oil fields. Most of the exploration has been done in the Gulf Coast area where all existing Mexican oil fields are located. A brief résumé is given of the main problems of the different provinces under exploration and a list of the fields discovered by Petróleos Mexicanos in the different provinces of the country. Geophysical methods have been responsible for location of a very large percent of the new fields. To compare the intensity of exploration in the United States and Mexico, the amount of seismic and gravity‐meter work and of wildcat drilling per million barrels of production is given for both countries. The data shows that Mexico’s level of geophysical exploration, per million barrels of oil produced, is very close to that of the United States. A very marked increase in the intensity of exploration is shown for both countries. Wildcat drilling in Mexico has been less intensive than in the United States but shows a definite tendency to increase; its present level is very close to that of the United States during 1940. The writer is of the opinion that the difference in intensity of wildcat drilling shown in the data presented is actually smaller than appears as there is a certain amount of duplication in the United States because of leaseholding problems.


Author(s):  
Kenneth G. Orr

A wealth of strikingly unusual and beautiful objects of Indian manufacture were excavated from the burials of the Spiro Mound, Leflore (sic.) County, Oklahoma during 1936-37. Engraved Gulf Coast conch shells, shell beads of a dozen types, river pearls, effigy pipes, long delicately chipped flint blades, feather and textile cloths and precisely incised pottery vessels were excavated in quantities. So unusual was this material that, at the time, the archaeological science was unable to answer a host of questions which immediately arose concerning the identity of the tribe who had made the artifacts and who were buried with them. How long ago had they occupied the region? From where had they come, and where did they go? The chronological relationship of the Spiro Mound Culture to the known cultures of the United States was of particular concern to the investigators. How and where did this tribe fit into the picture of America's past?


2018 ◽  
Vol 63 (sp1) ◽  
pp. 165 ◽  
Author(s):  
Deborah Carter ◽  
Paul Link ◽  
Patrick Walther ◽  
Andrew Ramey ◽  
David Stallknecht ◽  
...  

<em>Abstract.</em>—Because of their tendency to accumulate in estuaries and coastal regions, organochlorine (OC) contaminants such as pesticides and polychlorinated biphenyls (PCBs) represent potential threats to the quality of essential fish habitat for many shark species. These compounds pose special risks to immature sharks in particular because of their ability to impair growth and sexual maturation in juvenile fish at environmentally relevant levels of exposure. In order to assess the extent of these risks in shark populations on the East Coast of the United States, the present study examined concentrations of 30 OC pesticides/pesticide metabolites and total PCBs in juvenile sandbar <em>Carcharhinus plumbeus </em>and blacktip <em>C. limbatus </em>sharks from seven major nursery areas in the western Atlantic Ocean and eastern Gulf of Mexico. Quantifiable levels of PCBs and 13 OC pesticides/ pesticide metabolites were detected via gas chromatography and mass spectrometry in liver of 25 young-of-the-year blacktip sharks from the southeastern U.S. Atlantic coast and three regions on Florida’s gulf coast: Cedar Key, Tampa Bay, and Charlotte Harbor. Similarly, quantifiable levels of PCBs and 14 OC pesticides/metabolites were detected in 23 juvenile <em>C. plumbeus </em>from three sites on the northeastern U.S. coast: middle Delaware Bay, lower Chesapeake Bay, and Virginia’s eastern shore. Liver OC concentrations in Atlantic sandbar and blacktip sharks were higher than expected and, in some cases, comparable with elevated levels observed in deep-sea and pelagic sharks. Although significantly lower than those observed in Atlantic sharks, pesticide and PCB levels in Florida blacktip sharks were similar to, if not greater than, OC concentrations reported in adults of other coastal shark species. Based on these data, OC contamination appears to pose significant threats to habitat quality in sandbar and blacktip shark nursery areas on the U.S. Atlantic coast.


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