NEHRP Clearinghouse
- Title
- Stratigraphy, Structure, and Geologic and Coastal Hazards in the Penuelas to Salinas Area, Southern Puerto Rico: A Compendium of Published Literature.
- File
- PB2008105736.pdf
- Source
- January 2007, 33 p.
- Identifying Number(s)
- USGS-OFR-2007-1259
- Abstract
- The Puerto Rico Electrical Power Authority has proposed construction of a pipeline to convey natural gas from the municipio of Penuelas to the Aguirre thermoelectric power plant in the municipio of Salinas in southern Puerto Rico. To ensure that the geologic conditions along the possible routes do not represent a threat to the physical integrity of the natural gas pipeline, and thus comply with State and Federal regulations, the Puerto Rico Electrical Power Authority requested the U.S. Geological Survey to provide a synthesis of published literature of the geology of the coastal plain in the Penuelas to Salinas area.The study area is located in part of the Southern Coastal Plain of Puerto Rico. In the area that extends from the municipio of Penuelas eastward to the Laguna de las Salinas at Ponce, a distance of about 5 miles, the study area is underlain by middle Tertiary carbonate units. Eastward from the Laguna de las Salinas to the pipeline terminus at the Aguirre power plant in Salinas, a distance of about 30 miles, the terrain is underlain by fan-delta deposits of Quaternary age. The carbonate units and the fan-delta deposits are underlain by early Tertiary and older-age volcaniclastics with subordinate sedimentary rocks and lavas. The Great Southern Puerto Rico Fault Zone is the principal geologic structural feature in southern Puerto Rico. At present, the Great Southern Puerto Rico Fault Zone is considered largely quiescent, although it apparently is associated with minor earthquakes. There is no evidence of terrestrial, late Quaternary faulting within the Penuelas to Salinas area. Seismic activity in this area mostly originates from extension zones of more distal shallow sources such as Mona Canyon to the northwest and the Anegada Trough northeast of the island of Puerto Rico. The magnitude of completeness of earthquakes in the study area ranges from 2.0 to 2.5. The seismic density for the southern coast including the study area is about 0.128 earthquakes per square mile, which is close to the average for southwestern Puerto Rico.
- Keywords
- ; Lavas; Literature review; Southern Puerto Rico; Natural gas pipeline; Giology; Contruction; Fan-delta deposites; Sedimentary rocks; Coastal plain; Carbonate units; Penuelas to Salinas area