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Angel Martin

Publications and source records attributed to Angel Martin.

8 recordsLinked to original sources
USGS2010

User's guide for MAGIC-Meteorologic and hydrologic genscn (generate scenarios) input converter

Meteorologic and hydrologic data used in watershed modeling studies are collected by various agencies and organizations, and stored in various formats. Data may be in a raw, un-processed format with little or no quality control, or may be checked for validity before being made available. Flood-simulation systems require data in near real-time so that adequate flood warnings can be made. Additionally, forecasted data are needed to operate flood-control structures to potentially mitigate flood damages. Because real-time data are of a provisional nature, missing data may need to be estimated for use in floodsimulation systems. The Meteorologic and Hydrologic GenScn (Generate Scenarios) Input Converter (MAGIC) can be used to convert data from selected formats into the Hydrologic Simulation System-Fortran hourly-observations format for input to a Watershed Data Management database, for use in hydrologic modeling studies. MAGIC also can reformat the data to the Full Equations model time-series format, for use in hydraulic modeling studies. Examples of the application of MAGIC for use in the flood-simulation system for Salt Creek in northeastern Illinois are presented in this report.

Open-File Report↗
USGS2003

Arsenic in Illinois ground water — Community and private supplies

Assessing the distribution of arsenic in ground water from community-water supplies, private supplies, or monitoring wells is part of the process of determining the risk of arsenic contamination of drinking water in Illinois. Lifestyle, genetic, and environmental factors make certain members of the population more susceptible to adverse health effects from repeated exposure to drinking water with high arsenic concentrations (Ryker, 2001). In addition, such factors may have geographic distribution patterns that complicate the analysis of the relation between arsenic in drinking water and health effects. For example, arsenic may not be the only constituent affecting the quality of drinking water in a region (Ryker, 2001); however, determining the extent and distribution of arsenic in ground water is a starting place to assess the potential risk for persons drinking from a community or private supply. Understanding the potential sources and pathways that mobilize arsenic in ground water is a necessary step in protecting the drinking-water supply in Illinois.

Illinios↗
USGS1999

Hydrology of the coastal lowlands aquifer system in parts of Alabama, Florida, Louisiana, and Mississippi

Existing data on water levels, water use, water quality, and aquifer properties were used to construct a multilayer digital model to simulate flow in the aquifer system. The report describes the geohydrologic framework of the aquifer system, and the development, calibration, and sensitivity analysis of the ground-water-flow model, but it is primarily focused on the results of the simulations that show the natural flow of ground water throughout the regional aquifer system and the changes from the natural flow caused by development of ground-water supplies.

Alabama, Florida, Louisiana, Mississippi↗
USGS1987

Statistical analysis of aquifer-test results for nine regional aquifers in Louisiana

This report, prepared as part of the Gulf Coast Regional Aquifer-System Analysis project, presents a compilation, summarization, and statistical analysis of aquifer-test results for nine regional aquifers in Louisiana. These are from youngest to oldest: The alluvial, Pleistocene, Evangeline, Jasper, Catahoula, Cockfield, Sparta, Carrizo, and Wilcox aquifers. Approximately 1,500 aquifer tests in U.S. Geological Survey files in Louisiana were examined and 1,001 were input to a computer file. Analysis of the aquifer test results and plots that describe aquifer hydraulic characteristics were made for each regional aquifer. Results indicate that, on the average, permeability (hydraulic conductivity) generally tends to decrease from the youngest aquifers to the oldest. The most permeable aquifers in Louisiana are the alluvial and Pleistocene aquifers; whereas, the least permeable are the Carrizo and Wilcox aquifers. (Author 's abstract)

Water-Resources Investigations Report↗
USGS1985

Generalized potentiometric surface of aquifers of Pleistocene age, Southern Louisiana, 1980

A map of potentiometric surface defines generalized water levels for 1980 in the Pleistocene aquifers of southern Louisiana. The map was prepared as part of the Western Gulf Coast Regional Aquifer-System Analysis study. The Pleistocene deposits in southern Louisiana consist of alternating beds of sand, gravel, silt, and clay deposited under fluvial, deltaic, and near-short marine conditions. The aquifers are mainly under artesian conditions and the regional flow direction is primarily southward. Areally definable cones of depression result from heavy pumpage in the Baton Rouge, Lake Charles, and New Orleans metropolitan areas and in the rice irrigation area of southwestern Louisiana. Where water levels differ vertically within the aquifer, the lowest water levels in the vertical section were used because these levels represented the thickest and most heavily pumped unit in the aquifer. The map represents regional water levels in the Pleistocene aquifers, and is not intended to show localized variations near pumping centers. (USGS)

Water-Resources Investigations Report↗
USGS1985

Generalized potentiometric surface of the Evangeline and equivalent aquifers in Louisiana, 1980

A generalized potentiometric-surface map defines the altitude of water levels for 1980 in wells in the Evangeline aquifer in southwestern Louisiana and stratigraphically equivalent aquifers in southeastern Louisiana. The Evangeline and equivalent aquifers increase in thickness from zero at the northern edge of the outcrop/subcrop belt to more than 2,000 feet along the southern limit of fresh water. The aquifers are recharged by rainfall on the overlying upland terrace deposits of south-central Louisiana, southeastern Louisiana, and southwestern Mississippi. The aquifers are under artesian conditions except locally in the recharge areas. The regional flow direction is primarily southward. Water levels in wells in the Evangeline aquifer are lowered by heavy pumping from the overlying Chicot aquifer in Evangeline and Acadia Parishes. Areally definable cones of depression result from pumpage from the Evangeline and equivalent aquifers in and near Baton Rouge, Eunice, and Ville Platte. Water levels may differ vertically within the aquifer near pumping centers. The map does not account for localized distortion of the regional flow pattern near these centers.

Louisiana↗