Galveston Bay Information Collection Publications
http://hdl.handle.net/1834/17561
2024-03-29T08:13:24ZTrinity - San Jacinto estuary: A study of the influence of freshwater inflows
http://hdl.handle.net/1834/30189
Trinity - San Jacinto estuary: A study of the influence of freshwater inflows
The provision of sufficient freshwater inflow to Texas bays and estuaries is a vital factor in maintaining estuarine productivity, and a factor contributing to the near-shore fisheries productivity of the Gulf of Mexico. This report analyzes the interrelationships between freshwater inflows and estuarine productivity, and established the seasonal and monthly freshwater inflow needs, for a range of alternative management policies, for the Trinity- San Jacinto estuary of Texas. Simplifying assumptions must be made in order to estimate freshwater inflow requirements necessary to maintain Texas estuarine ecosystems. A basic premise developed in this report is that freshwater inflow and estuarine productivity can be examined through analysis of certain key indicators. The key physical and chemical indicators include freshwater inflows, circulation and salinity patterns, and nutrients. Biological indicators of estuarine productivity include selected commercially important species. Useful species are generally chosen on the basis of their wide distribution throughout each estuarine system, a sensitivity to change in the system, and an appropriate life cycle to facilitate association of the organism with estuarine productivity.
1981-04-01T00:00:00ZShoreline changes on Galveston Island (Bolivar Roads to San Luis Pass): An analysis of historical changes of the Texas Gulf shoreline.
http://hdl.handle.net/1834/30188
Shoreline changes on Galveston Island (Bolivar Roads to San Luis Pass): An analysis of historical changes of the Texas Gulf shoreline.
Morton, R.A.
Historical monitoring along Galveston Island records the type and magnitude of changes in position of the shoreline and vegetation line and provides insight into the factors affecting those changes. Documentation of changes is aided by the compilation of shoreline and vegetation line position from topographic maps, aerial photographs, and coastal charts of various vintages. Major and minor factors affecting shoreline changes include: (1) climate, (2) storm frequency, (3) local and eustatic sea-level conditions, (4) sediment budget, and (5) human activities. The major factors affecting shoreline changes along the Texas Coast, including Galveston Island, are a deficit in sediment supply and relative sea-level rise or compactional subsidence. Changes in the vegetation line are primarily related to storms. Studies indicate that shoreline and vegetation line changes on Galveston Island are largely the result of natural processes and their effects is requisite to avoid or minimize physical and economic losses associated with development and use of the beach.
1974-01-01T00:00:00ZGeothermal Resources Frio Formation, Upper Texas Coast
http://hdl.handle.net/1834/30187
Geothermal Resources Frio Formation, Upper Texas Coast
Bebout, D.G.; Loucks, R.G.; Bosch, S.C.; Dorfman, M.H.
The objective of this study is to identify major sand trends, which, along with subsurface temperatures and pressures, aid in evaluating the potential of producing geothermal energy from the Frio Formation, Upper Texas Gulf Coast. During the Tertiary, huge quantities of terrigenous sediments were deposited as gulfward-thickening sedimentary wedges along the Texas Gulf Coast. The sand and shale making up these wedges were transported across a broad fluvial plain and deposited in deltaic complexes or were reworked by marine processes into strandplains and barrier islands. Growth faults developed contemporaneously at the site of maximum deposition as a result of rapid loading of large quantities of deltaic and strandplain sands onto previously deposited prodelta and shelf muds. These growth faults allowed the accumulation of extremely thick sections of sand and also caused the isolation of many of these sand bodies from porous updip sands; pressured reservoirs developed after further loading and copaction (Bruce, 1973; Jones, 1975). This study is investigating geopressured geothermal reservoirs in this setting. Limited data obtained from deep wells drilled for oil and gas indicate that many of these large sand reservoirs are filled with water which has high temperature, is relatively low in total dissolved solids, and is saturated with methane gas. To be suitable for electric power generation, the reservoir shouls have a volume greater than 3 cubic miles (which is equivalent to 300 feet of sand distributed areally over more than 50 square miles), permeability greater than 20 millidarcies, and subsurface temperatures higher than 300 degrees F. This report reviews the results of the Bureau of Economic Geology regional study of the Frio Formation in the Upper Texas Gulf Coast. It is a continuation of two similar studies of the Frio in the Lower and Middle Texas Gulf Coast (Bebout, Dorfman, and Agagu, 1975; Bebout, Agagu, and Dorfman, 1975). The objective of these reports is to outline areas (fairways) which appear the most prospective for producing geothermal energy and which therefore deserve further, more detailed study.
1976-01-01T00:00:00ZOyster population trends in Galveston Bay, 1973-1978
http://hdl.handle.net/1834/30186
Oyster population trends in Galveston Bay, 1973-1978
Hofstetter, R.P.
Severe flooding on the Trinity River in 1973 destroyed oyster (Crassostrea virginica) populations in Trinity Bay and damaged those in the major harvest area in central Galveston Bay. Recovery was slow. Poor reproduction during 1975, 1976 and 1977 caused near depletion of oyster populations by spring 1978. However, abundant spat setting during 1978 resulted in an increase in small (seed) oysters in fall. Because market size oysters were scarce and seed oysters vulnerable to damage from oyster dredging, oystering in Galveston Bay was prohibited by proclamation of the Texas Parks and Wildlife Department (TPWD) effect 15 December 1978. Seasonal oyster harvests from public reefs in Galveston Bay ranged from 1.1 million kg (2.4 million lb) during 1976-77 to 8.7 thousand kg (19.2 thousand lb) during the abbreviated (45 day) 1978-79 seasons. As market oysters became scarce in Galveston Bay, oystering increased in mid-central bays. During the 1978-79 season, San Antonio Bay became the leading oyster producing area. The harvest of 359.5 thousand kg (792.7 thousand lb) established a record for that bay system. Private oyster lease production (confined to Galveston Bay) set a new record of 5861 meters cubed (7666.2 yards cubed). During 1976 only to be broken in 1977 when 7261 meters cubed (9497.4 yards cubed) were reported. Over a 23-year period, a decline in sample abundance of spat and small oysters has been observed although market oyster stocks remained relatively constant. A relationship between spring salinity values and spat setting was noted. Best spat sets usually occurred when salinity ranged 17-24 parts per thousand during spring. When salinity fell below 8 parts per thousand substantial spat sets did not occur.
1983-01-01T00:00:00Z