Holocene Surface Ruptures on the Salinas Fault and Southeastern Great Southern Puerto Rico Fault Zone, South Coastal Plain of Puerto Rico

2018 ◽  
Vol 108 (2) ◽  
pp. 619-638 ◽  
Author(s):  
Lucille A. Piety ◽  
Joanna R. Redwine ◽  
Sarah A. Derouin ◽  
Carol S. Prentice ◽  
Keith I. Kelson ◽  
...  
Keyword(s):  
Puerto Rico ◽  
Fault Zone ◽  
Coastal Plain ◽  
Surface Ruptures

scholarly journals Seismic Activity of the Manisa Fault Zone in Western Turkey Constrained by Cosmogenic 36Cl Dating

Geosciences ◽  
2021 ◽  
Vol 11 (11) ◽  
pp. 451
Author(s):  
Nasim Mozafari ◽  
Çağlar Özkaymak ◽  
Dmitry Tikhomirov ◽  
Susan Ivy-Ochs ◽  
Vasily Alfimov ◽  
...  
Keyword(s):  
Fault Zone ◽  
Normal Fault ◽  
Vertical Displacement ◽  
Historical Records ◽  
Western Turkey ◽  
Slip Rates ◽  
Vertical Displacements ◽  
Surface Ruptures ◽  
Fault Scarps ◽  
Calculated Average

This study reports on the cosmogenic 36Cl dating of two normal fault scarps in western Turkey, that of the Manastır and Mugırtepe faults, beyond existing historical records. These faults are elements of the western Manisa Fault Zone (MFZ) in the seismically active Gediz Graben. Our modeling revealed that the Manastır fault underwent at least two surface ruptures at 3.5 ± 0.9 ka and 2.0 ± 0.5 ka, with vertical displacements of 3.3 ± 0.5 m and 3.6 ± 0.5 m, respectively. An event at 6.5 ± 1.6 ka with a vertical displacement of 2.7 ± 0.4 m was reconstructed on the Mugırtepe fault. We attribute these earthquakes to the recurring MFZ ruptures, when also the investigated faults slipped. We calculated average slip rates of 1.9 and 0.3 mm yr−1 for the Manastır and Mugırtepe faults, respectively.

scholarly journals Performance of New Sugarcane Varieties in the Northern Humid Coastal Plains of Puerto Rico

1969 ◽  
Vol 60 (1) ◽  
pp. 61-77
Author(s):  
Rafael Gandía Caro ◽  
Carlos González Molina ◽  
Edwin Acevedo Borrero
Keyword(s):  
Puerto Rico ◽  
San Francisco ◽  
Coastal Plain ◽  
Growth Habit ◽  
Juice Quality ◽  
Coastal Plains ◽  
Sugarcane Varieties ◽  
New Varieties ◽  
Plant Crop

Three sites were selected in the northern humid coastal plains of Puerto Rico for the performance evaluation of 57 new sugarcane varieties. The experiments were located on typical soils of the sugarcane producing northern coastal plain region. A plant crop (fall planting) and two ratoons were harvested at each site. On the San Francisco farm between Arecibo and Utuado, the outstanding new varieties which outyielded all the others tested were PR 64-2548, PR 1152, PR 65-325 and PR 64-2705. Of these, PR 1152 and PR 64-2705 are the most promising varieties in this area because of their erect growth and the good quality of their juice. On the Las Claras farm, near Arecibo, the most promising new varieties for the area were PR 1141 and PR 62-258. On the Consejo farm at Barrio Bajadero, Arecibo, varieties PR 1117, PR 1152, Selección Soller, PR 1048, PR 62-469 and the PR 65-2523 performed best on the basis of cane tonnage. As a commercial variety for the area, PR 1152 was the most promising variety, having a good juice quality and intermediate cane tonnage per acre (40 to 45 tons). It can be harvested mechanically without difficulties because of its erect growth habit. PR 980 produced good tonnage, but was low in sucrose content, indicating that it should not be recommended for the northern humid coastal plains of Puerto Rico.

Hayward fault slippage in the Irvington-Niles districts of Fremont, California

1966 ◽  
Vol 56 (2) ◽  
pp. 257-279 ◽  
Author(s):  
Lloyd S. Cluff ◽  
Karl V. Steinbrugge
Keyword(s):  
Fault Zone ◽  
Time History ◽  
Wide Band ◽  
Strong Earthquakes ◽  
The Past ◽  
Parallel Lines ◽  
History Of ◽  
Surface Ruptures ◽  
Warm Springs

abstract Right lateral slippage on the Hayward fault has faken place in the Irvington and Niles districts of Fremont since the well known 1868 Hayward earthquake which produced surface ruptures from San Leandro to Warm Springs. This post-1868 movement has been occurring without being identified with strong earthquakes. Structures and railroads crossing the Hayward fault in the area under study date back to 1866. Fault slippage can be observed at ten separate locations along the strike of the Hayward fault in the Irvington-Niles districts of Fremont, California. One location predates the 1868 earthquake. There is no evidence for parallel lines of fault slippage within the approximately 200-foot wide fault zone. The slippage appears to have occurred within a 10-foot wide band parallel to the strike of the fault. Structures and railroads built at different times during the past 100 years give a time-history of the slippage. The slippage, if any, between 1868 and 1909 is unknown. From 1909 until as late as 1949 or early 1950, there was no observed fault slippage. Approximately one-half foot of slippage occurred between about 1949 or early 1950 and about 1957, and no measurable slippage since 1957.

Cenozoic crustal deformation of the offshore Burgos basin region (NE Gulf of Mexico). A new interpretation of deep penetration multichannel seismic reflection lines

2008 ◽  
Vol 179 (2) ◽  
pp. 161-174 ◽  
Author(s):  
Charlotte Le Roy ◽  
Claude Rangin
Keyword(s):  
Gulf Of Mexico ◽  
Fault Zone ◽  
Coastal Plain ◽  
Crustal Deformation ◽  
Seismic Reflection ◽  
Tectonic Activity ◽  
Normal Faults ◽  
Deep Penetration ◽  
Reverse Fault ◽  
Seismic Profiles

Abstract Along northeastern Mexico close to the Texas-Mexico border, the Burgos basin and its extension offshore was developed and deformed from the Paleocene up to Present time. This is a key triple junction between the sub meridian dextral transtensive coastal plain of the Gulf of Mexico extending far to the south in Mexico, the NE Corsair fault zone offshore and the sinistral Rio Bravo fault zone, a reactivated segment of the Texas lineament. Offshore NE Mexico, in the main study area covered by available seismic profiles, we have evidenced below the main well known gravitational décollement level (5 to 7 s twtt → 6 to 8 km) a Cenozoic deep-rooted deformation outlined by a N010° W trending deep-seated reverse fault zone and crustal folding down to the Moho (11 s twtt → ~ 20 km). Based on extensive offshore 2D industrial multi-channel seismic reflection surveys, deep exploration wells and gravimetric data, we focus our study on the deep crustal fabric and its effects on the gravitational tectonics in the upper sedimentary layers: submeridian crustal transtensional normal faults and open folding of the identified Mesozoic basement were interpreted as Cenozoic buckling of the crust during a major phase of oblique crustal extension. This deformation has probably enhanced gravity sliding along N030° growth-faults related to salt withdrawal and halokinesis in the offshore Burgos basin. We have tentatively made a link between this crustal deformation episode and the Neogene tectonic inversion of the Laramide foredeep basin of the Sierra Madre Oriental. The latter is still affected by crustal strike slip faulting associated with basaltic volcanism observed into the gulf coastal plain. This study favours a dominant crustal Cenozoic tectonic activity along the gulf margin without any clear evidence of Mesozoic tectonic reactivation. We propose that the large gravity collapse of the gulf margin was triggered by subsequent crustal deformation.

scholarly journals The Influence of Various N-P-K Fertilizer Levels on Onion Production in Southern Puerto Rico.

1969 ◽  
Vol 63 (2) ◽  
pp. 111-115
Author(s):  
S. Alers-Alers ◽  
E. Orengo-Santiago ◽  
L. Cruz Pérez
Keyword(s):  
Puerto Rico ◽  
Coastal Plain ◽  
High Fertility ◽  
Long Period ◽  
Yield And Quality ◽  
Average Production ◽  
The World ◽  
K Fertilizer ◽  
Onion Cultivar

An experiment was conducted on a San Anton (Cumulic Hasplustolls) fine loamy mixed isohyperthermic in the southern irrigated coastal plain of Puerto Rico, to evaluate the influence of various N-P-K levels on yield and quality of onion (cultivar Texas Grano 502). All P and K fertilizer were broadcast and mixed with the soil at planting. Half of the N fertilizer was broadcast at planting and half was banded 6 weeks later between rows and left uncovered. Mean yield differences attributable to fertilizer levels were not significant. The soil seems to have sufficient available native N to meet this crop's needs. This may be in part attributable to continuous fertilizer applications over the years for sugarcane production in this soil. An average onion production of 22 metric tons/ha was obtained. The world average production is 11 metric tons/ha. Based on the results obtained, the production of onions in th is soil is recommended for two reasons: 1) The high tonnage that can be obtained, and 2) the low investment on fertilizers if planted on soils of high fertility, especially if previously used for sugarcane and fertilized over a long period.

Tectonic Context and Possible Triggering of the 2019–2020 Puerto Rico Earthquake Sequence

2022 ◽  
Author(s):  
Marjolein Blasweiler ◽  
Matthew W. Herman ◽  
Fenna Houtsma ◽  
Rob Govers
Keyword(s):  
Puerto Rico ◽  
Fault Zone ◽  
Plate Boundary ◽  
Strike Slip ◽  
Global Navigation Satellite Systems ◽  
Earthquake Sequence ◽  
Motion Direction ◽  
Lateral Strike Slip ◽  
Coulomb Stress Changes ◽  
Stress Changes

Abstract An historically unprecedented seismic moment was released by crustal events of the 2019–2020 earthquake sequence near southwest Puerto Rico. The sequence involved at least two, and perhaps three interacting fault systems. The largest Mw 6.4 event was likely triggered by left lateral strike-slip events along the eastern extension of the North Boquerón Bay-Punta Montalva fault zone. The mainshock occurred in a normal fault zone that extends into a region where previous studies documented extensional deformation, beyond the Ponce fault and the Bajo Tasmanian fault. Coulomb stress changes by the mainshock may have triggered further normal-faulting aftershocks, left lateral strike-slip events in the region where these two fault zones interacted, and possibly right lateral strike-slip aftershocks along a third structure extending southward, the Guayanilla fault zone. Extension directions of the seismic sequence are consistently north-northwest–south-southeast-oriented, in agreement with the Global Navigation Satellite Systems-inferred motion direction of eastern Hispaniola relative to western Puerto Rico, and with crustal stress estimates for the overriding plate boundary zone.

Sign in / Sign up

Export Citation Format

Share Document