William E. Sweet

Natural Hydrocarbon Seepage in the Gulf of Mexico

ABSTRACT The Department of Oceanography at Texas AM and survivors of DeSotos group used tar found along the Texas-Louisiana coast to caulk their boats. From 1902-1909 heavy oil slicks were noted in an area about 100 miles south of the Louisiana coast and the locations plotted on charts issued by the United States Coast and Geodetic Survey. Oil spouting into the air was reported in the same area in 1909, as well as oil ponds off the Sabine Pass area. Reports of seeps in the Gulf of Mexico are numerous, and the Departments study has located several general areas of seepage within and around the Gulf. Tar samples from these areas have been collected and analyzed chemically, as well as samples found floating in the Gulf. The seep sites have been studied geologically and geophysically, and pertinent chemical, biological, and physical oceanographic characteristics have been determined.

Comparison of Geological and Engineering Parameters of Marine Sediments

Abstract : Various tests are conducted on sediment cores taken from the Gulf of Mexico in order to determine possible correlations between fast survey techniques and time-consuming laboratory tests.

Marine Acoustical Seep Detection

By 1952 the detection of hydrocarbon seeps had directed explorationists to more than 50 percent of the worlds oil reserves. As the major exploration emphasis shifts offshore the detection of seeps is again a potential indicator of new reserves. Rising gas bubbles can be detected with high-resolution subbottom profilers. This means that gas seeps can be detected and pinpointed during routine seismic surveys where high-resolution profilers are used.

Correlation of Cenozoic Sediments on Gulf of Mexico Outer Continental Shelf: Galveston Area Offshore Texas to Vermilion Area Offshore Louisiana (Part 1): ABSTRACT

Detailed stratigraphic correlations of the Texas and Louisiana outer continental shelf (OCS) of the Gulf of Mexico have been conducted for the past several years as part of the geological and geophysical effort included in the resource evaluation program. Part 1 of this study includes the area from Galveston, offshore Texas, to Vermilion, offshore Louisiana. Part 2 will extend down the Texas coast to Port Isabel. Part 3 will extend eastward beyond the Main Pass area. Other parts in the series are contemplated for the eastern gulf and the deep-water areas. The study area for part 1, Galveston through Vermilion, was selected because it is centrally located and includes portions of most of the productive trends on the federal OCS, and it includes a stratigraphically complex region characterized by the transition from the deltaic sedimentary sequences of the central Gulf of Mexico OCS to the offshore bar facies of the western Gulf of Mexico. The primary objective of this investigation is to establish a regional stratigraphic correlation grid including all major productive intervals based on electric-log, seismic, and paleontological data. Twenty-five stratigraphic horizons have been identified and regionally correlated. The correlations of regional markers are presented on both electric-log (geologic) cross sections and on seismic sections that closely parallel the geologic cross sections. The regional markers correlated on the E-logs were projected onto nearby seismic sections and correlated from well to well to verify the accuracy of the electric-log correlations. Time-depth values were calculated from borehole velocity surveys and integrated sonic logs. Approximately 30 electric log and 40 seismic sections have been constructed. Work on part 1 included the detailed analyses of more than 1,500 wells, three-quarters of which had paleontological data, and the interpretation of 12,000 line-mi of seismic data. End_of_Article - Last_Page 1429------------

Upper Sediment Column of Gulf of Mexico Presented in New Type of Map: ABSTRACT

Many types of investigations actually require information on the lithologic characteristics of the upper sediment column as well as the surface sediment characteristics. Selected cores from the Gulf of Mexico are presented as lithologic models. A chart symbol is used to indicate gross lithology. A numerical code has been developed which expresses lithologic percentages and indicates by positional notation vertical succession or intercalation of facies. For one area several cores were compared to demonstrate the validity of the developed technique and to show ratio changes. This new type of sediment-distribution map is of value in studies of sediment transport and deposition, basin filling, geotechnical properties, sea-laboratory preparation, salvaging of sunken objects, acoustical measurements, interpretation of shallow continuous reflection seismic profiling, etc. The sediment thickness represented on this new map is limited to the depth of penetration of the coring devices. End_of_Article - Last_Page 2033------------