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Ren Jen Sun

Publications and source records attributed to Ren Jen Sun.

5 recordsLinked to original sources
USGS1997

Bibliography of Regional Aquifer-System Analysis Program of the US Geological Survey, 1978-96

The Regional Aquifer-System Analysis (RASA) Program of the U.S. Geological Survey was initiated in 1978 and was completed in 1995. The purpose of this program was to define the regional geohydrology and establish a framework of background information on geology, hydrology, and geochemistry of the Nation's important aquifer systems. This information is critically needed to develop an understanding of the Nation's major ground-water flow systems and to support better management of ground-water resources. Twenty-five of the Nation's major aquifer systems were studied under this program. Starting in 1988, the program devoted part of its resources to compilation of a National Ground Water Atlas that presets a comprehensive summary of the Nation's major ground-water resources. The atlas, which is designed in a graphical format supported by descriptive text, serves as a basic reference for the location, geography, geology, and hydrologic characteristics of the major aquifers in the Nation. This bibliography lists 1,105 reports that result from various studies of the program. The list of reports for each study follows a brief description of that study.

Water-Resources Investigations Report↗
USGS1994

Regional Aquifer-System Analysis Program of the U.S. Geological Survey, 1978-1992

The major ground-water systems of the United States have been investigated by the U.S. Geological Survey (USGS) through its Regional Aquifer-System Analysis (RASA) Program. During the first 15 years of the program (1978-92), 25 regional aquifer systems, including the most heavily pumped aquifers in the Nation, were intensively studied. As of mid-1992, 18 of the regional aquifer studies are completed or nearly so; 7 of the regional aquifer studies are ongoing, and compilation of a national ground-water atlas is in progress. This report summarizes the status of each RASA study and briefly describes the hydrology of the 25 regional aquifer systems. Important study results and examples of applications of study results are presented for some of the completed RASA investigations. The major contributions of the RASA Program are (1) assembly of data from numerous local studies and long-time data collections into systematic regional data bases; (2) comprehensive descriptions of the geologic, hydrologic, and geochemical characteristics of the regional aquifer systems; and (3) an understanding of how the regional ground-water-flow systems function under natural (predevelopment) and current (developed) conditions. To provide the comprehensive system descriptions, many of the RASA studies present, for the first time, maps depicting the hydrogeologic frameworks, water chemistry, potentiometric surfaces, and other aspects of entire regional aquifer systems. To provide an understanding of how the flow systems function, several of the completed RASA studies provide, for the first time, hydrologic budgets for both predevelopment and developed conditions. The results of the RASA Program are contained in nearly 900 reports published by the USGS, as well as various State and local agencies, and in articles published in scientific journals. A series of U.S. Geological Survey Professional Papers are being published to summarize and synthesize the results of each RASA study.

Circular↗
USGS1991

Bibliography of Regional Aquifer-System Analysis Program of the US Geological Survey, 1978-91

The Regional Aquifer-System Analysis (RASA) Program of the U.S. Geological Survey was initiated in 1978. The purpose of this program is to define the regional geohydrology and establish a framework of background information on geology, hydrology, and geochemistry of the Nation's important aquifer systems. This information is critically needed to develop an understanding of the Nation's major ground-water flow systems and to support better management of ground-water resources. As of May 1991, 28 of the Nation's major aquifer systems have been identified for study under this program. Of these, 17 regional aquifer-system studies have been completed, and 8 studies are ongoing. Starting in 1988, the program devoted part of its resources to compilation of a Nationwide ground-water atlas that presents a comprehensive summary of the Nation's major ground-water resources. The atlas, which is designed in a graphical format supported by descriptive text, will serve as a basic reference for the location, geography, geology, and hydrologic characteristics of the major aquifers in the Nation. This bibliography lists the published 876 reports resulting from various studies of the program, from 1978 through May 1991. The list of reports for each study is placed after a brief description of that study.

Water-Resources Investigations Report↗
USGS1976

Artificial recharge through a well in fissured carbonate rock, west St. Paul, Minnesota

The Prairie du Chien Group was injected with 2,754,000 gallons (368,200 cubic feet), or 10,430 cubic metres, of municipally treated water at about 100 gallons per minute (13.4 cubic feet per minute), or 6.3 litres per second, for 20 days. The injection-pipe system was designed to utilize pipe friction rather than a remote-controlled valve in the well to maintain positive pressure and eliminate air entrainment in the injection water and the escape cf dissolved gasses from the water. During the 20-day injection period the temperature of the injection water declined gradually from 15.0 ° to 11.2 ° C, and the flow rate decreased from 108 to 90 gallons per minute (6.8 to 5.7 litres per second). Analyses of test data were, in some instances, based upon hydrologic judgement as well as observations. Results of aquifer tests before and after injections indicated that the transmissivity had decreased 18 percent during the intervening injection periods; however, the specific capacity remained the same, indicating no change in transmissivity during pumping. Analysis of water-level changes in observation wells during injection indicated a reduction in transmissivity of more than 50 percent; however, the specific capacity of the injection well decreased only about 5 percent during injection. A comparison of water-level changes with the discharge or recharge rates of the three tests showed that the water-level changes in the two observation wells tapping the Prairie du Chien Group during the injection test were greater than those projected from the two aouifer pumping tests. The deviations in the water-level changes and in the analysis of aquifer-test data indicate that the methods used to analyze data from these wells may not be wholly applicable, inasmuch as anisotropic and nonhomogeneous conditions prevail in at least the Prairie du Chien part of the aquifer. The native water and the injected water averaged 0.8 and 25 milligrams per litre chloride, respectively. The chloride, utilized as a tracer, showed that the injected water was detected only in the lower part of the nearest observation well, 99 feet (30.2 metres) from the injection well. The chemistry of the water and the rock formation showed little likelihood of plugging of the recharge well by chemical precipitation. Microbiological phenomena apparently did not become a significant factor in the recharge test. The hydraulic gradient of the aquifer in October and December 1971 (before and after injection) was estimated to be N. 36 ° E., 0.0013, and N. 39 ° E., 0.0012, respectively, on the basis of measurements of water levels in the three wells in the Prairie du Chien Group. The single-well tracer-dilution method of calculation showed a hydraulic gradient of 0.0016. A longitudinal dispersivity of 280 feet (85 metres) was calculated. Such a value of dispersivity is typical of fractured reservoirs and shows that the Prairie du Chien Group is a heterogeneous aquifer. The injection test demonstrated that it is hydrologically feasible to recharge the Prairie du Chien Group and the Jordan Sandstone artificially through wells completed in the Prairie du Chien Group. The fissures in the Prairie du Chien Group act as conduits through which water spreads. The water passes into the Jordan Sandstone from the Prairie du Chien over a larger area than it would if it were injected directly into the Jordan.

Minnesota↗