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Research about Gulf Coast region

Source-linked reports with geographic coverage including Gulf Coast region.

5 recordsLinked to original sources

Regional characterization of coal resources in the Gulf Coast Coal Region—In support of coal as a potential source for critical minerals and rare earth elements

There is increasing interest in extracting critical minerals (CM), including rare earth elements (REE), from coals in the United States to address the overreliance on imported REE. The Gulf Coast and the Fort Union regions are the two major lignite-bearing regions within the United States. Recent REE and CM studies of the lignite in these regions have indicated that the coals may be a viable source material for REE and CM extraction. To evaluate in-place coal as a potential source of REE and CM, the coal resources need to be quantified. This study presents the results of a regional analysis of Gulf Coast Coal Region lignite and bituminous coal resources that might be available as potential sources of REE and CM. The resource analysis used kriging methods to develop isopleth maps of cumulative coal thickness throughout the region using data from drill holes and measured mine and outcrop sections for a total of 31,181 data points. The estimated total remaining coal resource in the Gulf Coast Coal Region is about 83 billion metric tons in the upper 90 meters (approximately 300 feet) of the subsurface. The current estimate of remaining coal resources includes approximately 1.88 billion metric tons of coal that have been extracted in the region since 1983. Texas accounted for 39 percent (32 billion metric tons) of the remaining total resource, followed by Mississippi (24 percent, 20 billion metric tons ), Louisiana (14 percent, 12 billion metric tons), Tennessee (10 percent, 8.5 billion metric tons), and Arkansas (6 percent, 5.1 billion metric tons). Alabama, Georgia, Kentucky, and Missouri each accounted for less than 5 percent of the total resource; Georgia had the smallest resource estimated at 7 million metric tons. Here we report the first known statewide lignite resource estimates for Georgia, Kentucky (820 million metric tons), and Missouri (1,800 million metric tons). A comparison of the results of this study with those of previous Gulf Coast Coal Region and Fort Union Coal Region resource studies is difficult because each study used different data sources, assessment methodologies, overburden depths, and qualifying coal thicknesses.

Alabama, Arkansas, Florida, Georgia, Illinois, Lou↗

Detrital zircon age spectra of middle and upper Eocene outcrop belts, U.S. Gulf Coast region

Recently reported detrital zircon (DZ) data help to associate the Paleogene strata of the Gulf of Mexico region to various provenance areas. By far, recent work has emphasised upper Paleocene-lower Eocene and upper Oligocene strata that were deposited during the two episodes of the highest sediment supply in the Paleogene. The data reveal a dynamic drainage history, including (1) initial routing of western Cordilleran drainages towards the Gulf of Mexico in the Paleocene, (2) an eastward shift of the western continental divide, from the Jura-Cretaceous cordilleran arc to the eastern edge of the Laramide province after the Paleocene and (3) a southward shift, along the eastern Laramide province, of the headwaters of river systems draining to the Mississippi and Houston embayments at some time between the early Eocene and Oligocene. However, DZ characterisation of most (~20 Myr) of the middle Eocene-lower Oligocene section remains limited. We present 60 DZ age spectra, most of which are from the middle or upper Eocene outcrop belts, with 50–200-km spacing. We define six to eight distinct groups of DZ age spectra for middle and upper Eocene strata. Data from this and other studies resolve at least six substantial temporal changes in age spectra at various positions along the continental margin. The evolving age spectra constrain the middle and upper Eocene drainage patterns of large parts of interior North America. The most well-resolved aspects of these drainage patterns include (1) persistent rivers that flowed from erosional landscapes across the Paleozoic Appalachian orogen either into the low-lying Mississippi embayment or directly into the eastern Gulf; (2) at least during marine regressions, a trunk channel that likely flowed southward along the axial part of Mississippi Embayment and integrated tributaries from the east and west; and (3) rivers that flowed to the Houston embayment in the middle Eocene that likely originated in the Laramide province in central Colorado and southern Wyoming, as Precambrian basement highs in those source areas were being unroofed.

Gulf Coast region↗

Hurricane Sandy science plan: coastal topographic and bathymetric data to support hurricane impact assessment and response

Hurricane Sandy devastated some of the most heavily populated eastern coastal areas of the Nation. With a storm surge peaking at more than 19 feet, the powerful landscape-altering destruction of Hurricane Sandy is a stark reminder of why the Nation must become more resilient to coastal hazards. In response to this natural disaster, the U.S. Geological Survey (USGS) received a total of $41.2 million in supplemental appropriations from the Department of the Interior (DOI) to support response, recovery, and rebuilding efforts. These funds support a science plan that will provide critical scientific information necessary to inform management decisions for recovery of coastal communities, and aid in preparation for future natural hazards. This science plan is designed to coordinate continuing USGS activities with stakeholders and other agencies to improve data collection and analysis that will guide recovery and restoration efforts. The science plan is split into five distinct themes: • Coastal topography and bathymetry • Impacts to coastal beaches and barriers • Impacts of storm surge, including disturbed estuarine and bay hydrology • Impacts on environmental quality and persisting contaminant exposures • Impacts to coastal ecosystems, habitats, and fish and wildlife This fact sheet focuses on coastal topography and bathymetry. This fact sheet focuses on coastal topography and bathymetry.

Gulf Coast region↗

Map showing outcrop of the coal-bearing units and land use in the Gulf Coast region

This map is a preliminary compilation of the outcrop geology of the known coal-bearing units in the Gulf Coast Coal region. The map has been compiled for use in the National Coal Resource Assessment Project currently being conducted by the U.S. Geological Survey, and will be updated as the assessment progresses. The purpose of the map is to show the distribution of coal-bearing rocks in the Gulf Coastal Plain Region and to show stratigraphic correlations, transportation network, fossil-fuel burning power plants, and federally managed lands in the region. It is hoped that this map may aid coal exploration and development in the region. Geologic contacts were digitized from paper copies of the maps listed in the reference section below. The primary source of information was the 1:500,000-scale state geology map series, but larger scale maps were use to better define certain areas, notably the Jackson-Claiborne contact in western Kentucky and Tennessee for example (Olive, 1980). Contacts along state boundaries were modified to best-fit information available from the border areas. Note that coal distribution in the mapped units is not uniform. For example, the Jackson Group contains coal in Texas, but in Mississippi is not presently known to contain significant coal deposits. The unit is widespread and in part non-marine and thus of potential future interest. In contrast, the Jackson Group is not shown in Georgia where it is mostly marine and residuum (weathered material) at the surface. Tertiary age coal has also been noted in the Vicksburg Group (Oligocene) of Louisiana and Mississippi, but is not shown on this map. Contacts with mapped surficial units are not always shown. The locations of coal mine permit boundaries are based on information available at the time of publication and were obtained from the Division of Surface Mining and Reclamation, Railroad Commission of Texas, Austin, and the Injection and Mining Division, Department of Natural Resources, Baton Rouge, Louisiana. The correlation of map units and formation names generally follow Galloway and others (1991). We have placed the Paleocene-Eocene boundary in the middle of the Calvert Bluff Formation in Texas based on unpublished pollen biostratigraphy reports (N.O. Fredericksen, unpublished data, 1993; D.J. Nichols, unpublished data, 1996).

Alabama, Arkansas, Georgia, Florida, Kansas, Kentu↗

Geologic and hydrologic summary of salt domes in Gulf Coast region of Texas, Louisiana, Mississippi, and Alabama

There are 263 known or suspected onshore salt domes in the Texas-Louisiana-Mississippi-Alabama portion of the Gulf Coast geosyncline. The top of the salt in 148 of them is probably deeper than desirable for a waste repository site, and 79 of those that are shallow enough are probably unavailable for a site because of present use by industry for gas storage or production of oil, salt, or sulfur. In this report we have compiled the available geologic and hydrologic background data pertinent to the evaluation of the remaining 36 known or suspected salt domes as potential sites for waste storage. There are three parts to this compilations: 1) summaries of the geology and hydrology of the salt-dome province as a whole; 2) summaries of the physiography, climate, geology, and hydrology of each of the five salt-dome basins that occur within the province; and 3) an appendix of background data for each of the 36 potentially acceptable domes. The distribution of salt domes in the province is genetically related to areas of relative subsidence that formed basins or depocenters within the Gulf Coast geosyncline. In some cases, as in northeast Texas and south Louisiana, the locations of individual domes or groups of domes are related to deep movement of salt along axial trends. The salt domes in the interior salt-dome subprovince are probably more structurally stable than those of the coastal subprovince because salt diapirism is inferred to have ceased around Miocene time in the interior but may still be active in parts of the coastal subprovince. Although the size and shape of many domes is unknown or can only be roughly approximated, each of the five basins in the province appears to contain potentially acceptable domes of adequate size for a repository. We recognize no pattern to the distribution of salt-dome size. Caprock thicknesses vary greatly within each salt-dome basin,and we recognize no pattern to the variations. Among the potentially acceptable domes, the depths to the top of the salt are generally greatest in the Mississippi salt-dome basin, where all tops are more than 1,500 feet deep. Intermediate depths of about 1,000 feet are common in the east Texas-south Louisiana salt-dome basin. Depths to salt tops in the north Louisiana and northeast Texas basins are variable but most are less than 1,000 feet. Available drilling records are generally adequate to determine the number of wells drilled on or in the vicinity of individual domes and also the well locations. The numbers of wells vary widely within each salt-dome basin. More salt domes are currently available for use as repository sites in the interior subprovince than in the coastal subprovince, where the pressure for industrial use of domes is high. In the interior subprovince many of the potentially acceptable domes are located beneath hilly well-drained terrain that is not subject to flooding or other surface-water problems. Although topographic depressions occupied by shallow lakes, swamps, or 'salines' occur over several of the domes, they are generally flanked by topographically high ground where surface facilities could be sited without complications.A few of the potentially acceptable domes are located beneath floodplains where surface facilities might face hazards from flooding. In the coastal subprovince several of the potentially acceptable domes are located in relatively flat poorly drained terrain where surface flooding might constitute a potential hazard. The availability of fresh to slightly saline ground water varies considerably within each salt-dome basin. We have outlined some of the factors that are responsible for the variations and have provided or referred to maps and geohydrologic cross sections that illustrate the general distribution of fresh to slightly saline water. The top of the salt in about half of the known potentially acceptable domes is below the regional base of the fresh to slightly saline ground-water system, but in a few of

Alabama, Louisiana, Mississippi, Texas↗