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Research about Puerto Rico

Source-linked reports with geographic coverage including Puerto Rico.

At least 361 records · Page 20Linked to original sources
USGS1971

Water resources of the Coamo area, Puerto Rico

This study, like other similar studies, was made possible by a cooperative water-resources program between the U.S. Geological Survey and the Puerto Rico Water Resources Authority (at the time), representing also the Puerto Rico Aqueduct & Sewer Authority and the Puerto Rico Industrial Development Company. This report covers the hydrologic investigation made in 1967 in the Coamo area, on the south coast of Puerto Rico. The purpose of the investigation was to make a preliminary, intensive reconnaissance of the water resources of the area. Emphasis was on the Coamo fan, which is essentially coextensive with the coastal plain. The scope of the investigation covered the collection, analysis, and interpretation of hydrologic data so as to arrive at a linkage between how much, where, and what type of water is available in relation to the water needs of the area (largely for irrigation). This report is based in good part on the field work of Ralph Gonzalez, hydrologic assistant for the project, who installed and maintained in working order most of the recording instruments and collected most of the field data. We acknowledge the cooperation of Luce & Company, owner or user of most of the water wells in the area. Its personnel guided us to their wells and provided invaluable records on well yield and rainfall.

Coamo↗
USGS1971

Floods in the Guayanilla-Yauco area, Puerto Rico

This report is a compilation of data pertaining to floods in Rios Guayanilla and Yauco and is based principally upon information obtained from residents in the study area. This information is a useful tool in making land-use and development decisions. The Guayanilla and Yauco basins lie in the southwestern part of Puerto Rico. The streams flow southward from the rugged Cordillera Central and empty into Bahia de Guayanilla. The lower basins are devoted principally to the production of sugarcane and are subject to destructive floods. Details pertaining to basin features, flood frequency, flood profiles, and inundated areas are discussed by individual basins. All elevations given are in meters above mean sea level.

Puerto Rico↗
USGS1970

A gravity and aeromagnetic survey of the mid-Tertiary sedimentary basin on the south coast of Puerto Rico

During the period November 18, 1963 to December 3, 1963 the U.S. Geological Survey in cooperation with the Commonwealth of Puerto Rico performed a gravity survey of the Tertiary sedimentary basin which is located along the south coast of Puerto Rico in the vicinity of Ponce. The project was initiated at the request of Mr. Carlos Vincenty, Director, Department of Industrial Research, Economic Development Administration of the Commonwealth of Puerto Rico. The purpose of the survey was to obtain information on the configuration arid structure of the basin and if possible, to locate areas which might be favorable for the accumulation of oil or gas. The accompanying index map (fig. 1) shows the survey area together with the outline of the border of the basin.

Puerto Rico↗
USGS1970

A proposed streamflow-data program for Puerto Rico

The streamflow-data program of the U.S. Geological Survey (USGS) in Puerto Rico has been one of the principal parts of an overall appraisal of the water resources of the Island since the initiation of a cooperative agreement with agencies of the Commonwealth Government in 1957. The streamflow-station network has increased in direct response to demand for data to support planning for the rapidly accelerated industrial and population growth that has occurred since.

Puerto Rico↗
USGS1969

Floods in the Guayanilla-Yauco area, Puerto Rico

This report is a compilation of data pertaining to floods in Rios Guayanilla and Yauco, based principally upon information obtained from residents in the study area. This information is a useful tool in making land-use and development decisions. The Guayanilla and Yauco basins lie in the southwestern part of Puerto Rico. The streams flow southward from the rugged Cordillera Central and empty into Bahia de Guayanilla. The lower basins are devoted principally to the production of sugarcane and are subject to destructive floods. Details pertaining to basin features, flood frequency, flood profiles, and inundated areas are discussed by individual basins. All elevations given are in meters above mean sea level.

Guayanilla-Yauco area↗
USGS1968

The age of the Puerto Rico Trench

The Puerto Rico Trench is parallel to and north of Puerto Rico and the Virgin Islands and reaches depths of more than 8000 meters. Puerto Rico, the closest land area, has a central longitudinal core of Cretaceous and early Tertiary volcanic rocks, some serpentinite of undetermined age, and numerous small intrusions. These rocks were folded into an anticlinorium and intensely faulted into hundreds of fault blocks in an orogeny that lasted from Late Cretaceous until middle Eocene time. Most fold axes and the major fault zones trend approximately west-northwest at an angle of about 15° to the general trend of the island and to the Puerto Rico Trench. Near the north coast, late Oligocene rocks rest on a truncated surface of Cretaceous and early Tertiary volcanic rocks. The Oligocene and overlying Miocene sedimentary rocks strike approximately east, parallel to the Puerto Rico Trench. Apparently the trench is not related to the tectonic movements that folded and faulted the Cretaceous and early Tertiary rocks, but it is closely related tectonically to the Oligocene and Miocene rocks. The trench probably first appeared in Oligocene or possibly late Eocene time and may have reached its maximum depth in late Miocene or Pliocene time.

Puerto Rico↗
USGS1968

Gneissic amphibolite at Las Palmas, Puerto Rico, and its significance in the early history of the greater antilles island arc

The basal complex of Puerto Rico consists principally of serpentinite, minor amounts of chert and spilite, and locally small blocks of amphibolite . A detailed structural and metamorphic study of a relatively large block of gneissic amphibolite at Las Palmas reveals that the rock has undergone repeated deformation and regional metamorphism prior to contact metamorphism by intrusive serpentinite. The first event recorded by the amphibolite is amphibolite facies regional metamorphism. Foliation and some hornblende lineation were formed at this time. An increase in the intensity of regional metamorphism then produced quartzo-feldspathic segregations from the host rock, and was accompanied by small-scale folding and development of several types of lineation oblique (o the early hornblende lineation. The metamorphic intensity then decreased slightly and tectonic movement radically decreased, as nonfoliated but metamorphosed mafic dikes cut the gneissic amphibolite . As the metamorphic grade decreased further, late-stage kink-bands were developed at high angles to the earlier small-scale folding. Later, the amphibolite was intruded by serpen-tinite, causing incipient low-grade contact metamorphism and some calcium metasomatism. H. H. Hess has maintained that Puerto Rico and other islands in the Greater Antilles rest directly on oceanic crust, and that the intrusive serpentinite is derived from the bottom layer of the crust. In the Las Palmas area, the amphibolite formed prior to intrusion of serpentinite, indicating a complex preserpentinite history . Three interpretations of the gneissic amphibolite are considered. It may represent: (1) metamorphosed gabbroic rocks genetically related to the serpentinite, (2) regionally metamorphosed mafic rocks that are part of the oceanic crust, or (3) older mafic rocks regionally metamorphosed as part of an extensive pre-Late Cretaceous orogeny. The evidence from Las Palmas is not conclusive, but when considered in the regional framework, either of the last two interpretations seems reasonable.

Puerto Rico↗
USGS1968

Water resources of the Juana Díaz area, Puerto Rico: A preliminary appraisal, 1966

This report is an areal study of a portion of the south coast of Puerto Rico. It follows similar studies of the Guanica, Guayanilla-Yauco, Tallaboa Valley, and Ponce areas to the west and the Jobos area to the east. It basically is an inventory of the water resources during one year. To this extent it carries no long-term information; however, as rainfall data is available for 50 years or so at some sites within the study area, we can make a qualitative estimate of the water resources under more extreme conditions. The purpose of this report, then, is to evaluate the gross hydrologic features of the area for the future management of the water resources.

Juana Díaz↗
USGS1967

Water resources of the Guanica area, Puerto Rico: A preliminary appraisal, 1963

Guánica and the lower Rio Loco valley lie between the extensive agricultural development in Lajas Valley to the west and the industrial development at Guayanilla to the east. Having a protected deep-water port, the Guánica area is particularly well suited to further development. The economic growth of the area depends, in important degree, on the amount of water available-water in the immediate area or water to be brought in from other areas. The purpose of the study of the Guánica area was to evaluate the water supply in the immediate area. How much water is there? How much water moves through the area and what are the factors that control the movement? What is the composition of the water? And how much more water can be used? The study itself took one year. Active data collection included measurements of streamflow, measurements of water levels in wells, measurements of well discharge, chemical analyses of surface and ground water, geologic reconnaissance, and considerable interviewing. Information for more than one year was obtained for rainfall and other weather data, well pumpage, water leaving Lago loco, and water used by the Southwestern Puerto Rico project.

Guanica↗