Search USGS⌕ Search

Geology topics

Research about Puerto Rico

Source-linked reports with geographic coverage including Puerto Rico.

At least 289 records · Page 16Linked to original sources

Bibliographies and location maps of aeromagnetic and aeroradiometric publications for Puerto Rico and large areas of the conterminous United States

Bibliographies and location maps of selected publications containing aeromagnetic and/or aeroradiometric data have been compiled for each state. These state indexes have been grouped together to form seven open-file reports: four for the conterminous United States (see index map below), one for Alaska and Hawaii, one for Puerto Rico and large areas of the United States (U.S. Regional), and one for the Department of Energy (DOE) National Uranium Resource Evaluation (NURE) Program reports.

Puerto Rico↗

Restoration of freshwater in the Cano Tiburones area, Puerto Rico

Cano Tiburones on the north coast of Puerto Rico originally was a shallow, coastal lagoon, 9 square miles in area. It accumulated freshwater from adjacent rivers and springs and drained to the ocean through unobserved subterranean conduits. Forced drainage by pumping of Cano Tiburones for agriculture was begun in 1949, and resulted in lowering the water level to below sea level. The reversed hydraulic gradient permitted seawater to enter the Cano through the conduits forming seawater "springs". Seawater flooding caused widespread sodium chloride contamination in the canals and laterals and in the soils. Agricultural expectations of the area were not realized. The present investigation into the freshening potential of Cano Tiburones (1979-1982) determined that ground-water discharge does not contribute to salty conditions. On-site experiments were performed to segregate freshwater from seawater using differences in hydraulic head. Dams were constructed on canals and laterals, forcing accumulated saltwater to the ocean. Ring levees were placed around the discharging seawater conduits until sea level was reached and flow to the system stopped. These efforts have succeeded in reducing the amount of seawater in Cano Tiburones to one-third of its original concentration. Most of the water presently in Cano Tiburones is suitable for irrigation.

Cano Tiburones↗

Hydrogeochemical prospecting for porphyry copper deposits in the tropical-marine climate of Puerto Rico

A hydrogeochemical survey utilizing waters from streams and springs was conducted in the area of two known porphyry copper deposits in the tropical-marine climate of westcentral Puerto Rico. The most important pathfinder for regional hydrogeochemical surveys is sulfate which reflects the associated pyrite mineralization. Because of increased mobility due to intense chemical weathering and the low pH environment, dissolved copper can also be used as a pathfinder for regional surveys and has the advantage of distinguishing barren pyrite from pyrite associated with copper mineralization. For follow-up surveys, the most important pathfinders are copper, sulfate, pH, zinc, and fluoride. High concentrations of dissolved copper and moderate concentrations of sulfate is a diagnostic indication of nearby sources of copper minerals. An understanding of the geochemical processes taking place in the streambeds and the weathering environment, such as the precipitation of secondary copper minerals, contributes to the interpretation of the geochemical data and the selection of the most favorable areas for further exploration.

Puerto Rico↗

Flood of September 16, 1975 in the Guayanilla Valley, Puerto Rico

This report provides hydrologic and hydraulic information related to the flood of September 16, 1975 in the Guayanilla Valley. The information presented is a compilation of data recovered by the U.S. Geological Survey, and information provided by the residents in the study area.

Puerto Rico↗

Geohydrologic descriptions of selected solid waste disposal sites in Puerto Rico

Fifty solid-waste disposal sites in Puerto Rico were examined in 1977 and ranked according to their potential for degradation of the water resources. Twenty-five of the sites show significant leachate pollution potential. The cover material at 21 sites is relatively permeable and offers insignificant attenuation to leachates. Thirty-six sites are adjacent to streams and nine of these are located in headwater areas. Rainfall is abundant and at 40 of the sites exceeds 1,500 millimeters per year. General descriptions of the 50 disposal sites are given with their geohydrologic setting. Baseline data consisting of specific conductance, pH, temperature, dissolved oxygen, and common ions were obtained at many of the sites. Such information provides a technical basis for assessing future effects of those solid-waste disposal sites on the quality of water resources.

Puerto Rico↗