scholarly journals Demersal assemblages of the continental shelf and slope edge between the Gulf of Tehuantepec (Mexico) and the Gulf of Papagayo (Costa Rica)

1991 ◽  
Vol 73 ◽  
pp. 121-140 ◽  
Author(s):  
G Bianchi
Keyword(s):  
Costa Rica ◽  
Continental Shelf ◽  
Gulf Of Tehuantepec

scholarly journals Bivalves and Gastropods of the Gulf of Tehuantepec, Mexico: A Checklist of Species with Notes on Their Habitat and Local Distribution

2009 ◽  
Vol 2009 ◽  
pp. 1-12 ◽  
Author(s):  
Eduardo Ríos-Jara ◽  
Ceciel-M. Navarro-Caravantes ◽  
Cristian-M. Galván-Villa ◽  
Ernesto Lopez-Uriarte
Keyword(s):  
Continental Shelf ◽  
Coastal Lagoons ◽  
Taxonomic Composition ◽  
Total Count ◽  
Bivalve Species ◽  
Local Distribution ◽  
Gastropod Species ◽  
Gulf Of Tehuantepec ◽  
Shallow Subtidal

The taxonomic composition of 160 species of bivalves and gastropods recorded in the Gulf of Tehuantepec is presented with information on their habitat and distribution along 10 different localities of the shoreline and 42 stations of the continental shelf. The species were on sandy and rocky beaches, coastal lagoons, estuaries, mangroves, rocky breakwaters of ports, and shallow subtidal areas (14–47 m depth). A total of 78 bivalve species and 82 gastropod species were recorded. Most of these were associated with sandy and rocky beaches and breakwaters of ports. The estuaries host 30 species and the coastal lagoons only two. In the shallow subtidal there were 18 gastropod species and 40 bivalve species representing 36.3% of all. This study adds 24 bivalve species and 29 gastropod species not recorded in previous studies for a total count of 213 species (102 bivalves and 111 gastropods) for Gulf of Tehuantepec.

scholarly journals MOLUSCOS MARINOS DE LA ISLA DE GORGONA (COSTA DEL PACIFICO COLOMBIANO)

2016 ◽  
Vol 14 ◽  
Author(s):  
Rudo Von Cosel
Keyword(s):  
Costa Rica ◽  
South America ◽  
Continental Shelf ◽  
Central America ◽  
Pacific Coast ◽  
Northern Limit ◽  
Marine Mollusk ◽  
Distribution Limit ◽  
Mollusk Species

319 marine mollusk species collected yet on Gorgona Island (Pacific coast of Colombia, Panamic zoogeographic province) by various persons and scientific expeditions are listed. 209 species (65.5%) inhabit the whole province (México to Ecuador or Perú), 21 species (6.6%) are known from the southern part (Central America to Ecuador or Perú) and 4 species (1.3%) have their presently known northern limit in Gorgona and spread south to Ecuador or Peru. 42 species (13.2%) have their presently known southern distribution limit in Gorgona, 14 other species (4.4%) reaching in Gorgona their southernmost point on the continental shelf of South America are also known from Galapagos. 3 species (1.0%) have been collected on the continental shelf only in Gorgona and partly in Costa Rica. The distribution of the remaining 25 species (7-9%) is still not sufficiently known. 119 species from Gorgona have not yet been found on the mainland coast of Colombia. 8 species are amphipacific. The zoogeographic importance of Gorgona Island is based in the fact that the island is the southernmost point on the continental shelf with extensive coraline biotopes within the Panamic-Pacific faunal province.

The Costa Rica Coastal Current, eddies and wind forcing in the Gulf of Tehuantepec, Southern Mexican Pacific

2016 ◽  
Vol 114 ◽  
pp. 1-15 ◽  
Author(s):  
Cristóbal Reyes-Hernández ◽  
Miguel Ángel Ahumada-Sempoal ◽  
Reginaldo Durazo
Keyword(s):  
Costa Rica ◽  
Wind Forcing ◽  
Coastal Current ◽  
Mexican Pacific ◽  
Gulf Of Tehuantepec

scholarly journals Environmental characterization of the continental shelf of the Gulf of Tehuantepec, Mexico

2007 ◽  
Vol 46 (4) ◽  
pp. 249-260
Author(s):  
M. Tapia-Garcia ◽  
M. C. Garcia-Abad ◽  
A. Carranza-Edwards ◽  
F. Vazquez-Gutierrez
Keyword(s):  
Continental Shelf ◽  
Environmental Characterization ◽  
Gulf Of Tehuantepec

Se analizan datos e información de las características fisco-químicas del agua y tipo de sedimentos de la plataforma continental del Golfo de Tehuantepec, México. Los cambios de salinidad, temperatura y oxígeno disuelto varían de acuerdo con las estaciones de lluvias y sequía (en esta última prevalecen fuertes vientos denominados Tehuantepecanos). Las estaciones de muestreo fueron agrupadas (utilizando salinidad, temperatura, pH y tipo de sedimentos) con análisis por conglomerados y análisis de factores. Los resultados indican que el Golfo de Tehuantepec tiene dos subsistemas. El subsistema Oaxaqueño se localiza frente a la zona entre Salina Cruz y la boca de Tonalá y se extiende hacia el sur-sudeste; este subsistema se caracteriza por presentar surgencias que producen valores bajos de temperatura, oxígeno disuelto y altas concentraciones de nutrimentos, escasas descargas de ríos y sedimentos arenosos. El subsistema Chiapaneco se localiza frente a la zona entre la boca de Tonalá y el río Suchiate, con fuerte influencia de lagunas costeras y descargas de ríos; se caracteriza por sedimentos arenosos y lodoso-arenosos, y no presenta surgencias. Estos subsistemas y sus características probablemente determinan el patrón de distribución de los recursos bióticos.

scholarly journals Timing of environmental change in Caribbean shallow waters relative to the closure of the Tropical American Seaway: evidence from benthic foraminifera

1992 ◽  
Vol 6 ◽  
pp. 67-67
Author(s):  
Laurel S. Collins
Keyword(s):  
Costa Rica ◽  
Environmental Change ◽  
Continental Shelf ◽  
Benthic Foraminifera ◽  
Environmental Changes ◽  
Environmental Indicators ◽  
Shallow Waters ◽  
Southern Caribbean ◽  
The Caribbean ◽  
Upper Slope

The most significant change in Pliocene oceanic circulation resulted from closure of the Tropical American Seaway between the Caribbean Sea and Eastern Pacific Ocean around 3 Ma. Faunal changes in Caribbean shallow-water marine organisms such as mollusks and corals have been attributed to possible environmental changes associated with this event, including cyclical cooling, initiation of a carbonate regime in the southern Caribbean, and upwelling of deeper waters on the continental shelf, but their occurrences and timing have been unclear.This study uses the ecological and evolutionary record of benthic foraminifera of the upper continental slope to inner continental shelf to investigate environmental change in Caribbean shallow waters with respect to final closure of the interoceanic seaway. Benthic foraminifera are useful as environmental indicators so periods of increased taxonomic turnover should correspond to times of environmental change. Over 100 species commonly occurring in deposits of Caribbean Panama and Costa Rica dated from 6.5 to 1.6 m.y. were taxonomically standardized with existing literature and collections to produce stratigraphic ranges within the Caribbean region.Although an average common species has lived from Early Miocene times until today, an increase in first appearances suggests that an interval of ecological restructuring occurred on the continental shelf to upper slope in latest Miocene time. The last 15 m.y. includes about 45% of the first and last appearances, 70% of which are comparably dated in other Caribbean strata. For the period from 15 to 3 Ma, about 75% of first appearances occurred between 7 and 3 Ma, and more than twice as many occurred between 7 and 5 Ma as occurred before or after that interval. Comparable numbers of continental shelf and slope taxa have first occurrences between 7 and 5 Ma, indicating a general change on the continental shelf to upper slope in the latest Miocene which preceded closure of the interoceanic seaway by 2 to 4 m.y. Few extinctions occurred in the last 7 m.y.; 86% of the common taxa less than 7 m.y. old in Panama and Costa Rica have survived to the present. The appearance of carbonate-loving species in Panama to Costa Rica at 4.6–5.0 Ma and northern Colombia by 5.0 Ma indicates a well established carbonate regime in the southern Caribbean by earliest Pliocene time. Benthic foraminiferal assemblages show no evidence of upwelling in the Panama-Costa Rican region through the Pliocene.The Late Miocene environmental changes in shallow Caribbean waters preceded isotopic changes in open-ocean surface waters that occurred 4 to 3 Ma. Ecological restructuring took place in the latest Miocene, several m.y. before the seaway closed, and any subsequent environmental changes had little effect on benthic foraminifera of the Caribbean continental shelf.

scholarly journals Biogeographical affinities of fish associated to the shrimp trawl fishery in the Gulf of Tehuantepec, Mexico

2016 ◽  
Vol 64 (2) ◽  
pp. 683 ◽  
Author(s):  
Marco Antonio Martínez-Muñoz ◽  
Domènec Lloris ◽  
Adolfo Gracia ◽  
Ricardo Ramírez-Murillo ◽  
Saul Sarmiento-Nafáte ◽  
...  
Keyword(s):  
Species Composition ◽  
Continental Shelf ◽  
Local Environment ◽  
Wide Distribution ◽  
Composition Distribution ◽  
Shrimp Fishery ◽  
Trawl Fishery ◽  
Shrimp Trawl ◽  
Gulf Of Tehuantepec ◽  
By Catch

Fish by-catch of the Gulf of Tehuantepec shrimp fishery is mainly composed of several species that are discarded in their majority. Fish by-catch species composition, distribution and biogeographical affinities were analyzed through 15 cruises carried on the continental shelf at a depth of 12 to 70 m during 2003, 2004, 2005 and 2013. Fish by-catch was represented by 58 families, 129 genera and 242 species. The families Haemulidae, Sciaenidae, Paralichthyidae, Gerreidae and Carangidae accounted for &gt;70% of the catch. <em>Haemulopsis axillaris</em>, <em>Syacium ovale</em>, <em>Selene peruviana</em>, <em>Diapterus peruvianus</em>, <em>Larimus acclivins</em> and <em>Stellifer erycimba</em> were the most frequent species at &lt;40 m depth (inner shelf), and <em>Prionotus stephanophrys</em>, <em>Scorpaena russula</em>, <em>Porichthys analis</em> and <em>Synodus scituliceps</em> were dominant at 40−60 m depth (outer shelf). Analysis of biogeographical affinities showed that 36.1% of species had a wide distribution, from San Diego Province to the Panamic Province, while 13.2% had a restricted distribution in the Mexican and Panamic Provinces. The ichthyofaunal composition was markedly influenced by the local environment and seasonal conditions.

scholarly journals Influence of incoming plate relief on overriding plate deformation and earthquake nucleation: Cocos Ridge subduction (Costa Rica)

2020 ◽  
Author(s):  
Sara Martínez-Loriente ◽  
Valentí Sallarès ◽  
César R. Ranero ◽  
Jonas B. Ruh ◽  
Udo Barckhausen ◽  
...  
Keyword(s):  
Costa Rica ◽  
Continental Shelf ◽  
Velocity Structure ◽  
Numerical Models ◽  
P Wave ◽  
Seismic Reflection Profile ◽  
Rock Fracturing ◽  
Ridge Subduction ◽  
Shelf Sediment ◽  
Earthquake Nucleation

&lt;p&gt;We present a 2D p-wave velocity (Vp) model and a coincident multichannel seismic reflection profile mapping the structure of the southern Costa Rica margin and incoming Cocos Ridge. The seismic profiles image the ocean and overriding plates from the trench across the entire offshore margin, including the structures involved in the 2002 Mw6.4 Osa earthquake. The overriding plate consists of three domains: Domain I at the margin front displays thin-skinned deformation of an imbricated-thrust system composed of fractured rocks with relatively low Vp. Domain II under the middle continental shelf is comparatively less fractured, showing ~15 km long landward-dipping reflection packages and discrete active deformation of the shelf sediment and seafloor. Domain III in the inner shelf is little fractured and appears to be dominated by elastic deformation, with inactive structures of an extensional basin consisting of tilted blocks overlain by ~2 km-thick gently landward-dipping strata. The velocity structure supports the argument that the bulk of the margin is highly consolidated rock possibly similar to outcrops in the Osa Peninsula. Thick-skinned tectonics probably causes the uplift of Domains II and III. The incoming oceanic plate shows crustal thickness variations from ~14 km at the trench (Cocos Ridge) to 6-7 km beneath the continental shelf. We combine (1) inter-plate geometry and velocity-derived fracturing degree at the base of the overriding plate, (2) tectonic stresses and brittle strain above the inter-plate boundary extracted from 3D numerical models, and (3) earthquake locations, to investigate potential relationships between structure and earthquake generation. The 2002 Osa earthquake and its aftershocks appear to have nucleated at the leading flank of two subducting seamounts, coinciding with the area of highest tectonic overpressure in numerical models. Both estimated rock fracturing and modelled brittle strain, steadily increase from the leading flank of the subducting seamounts to their top, which we interpret to reflect the progressive damage caused by the incoming plate relief. Therefore, the analysis supports a spatial and temporal relationship between subducting seamount location, upper plate fracturing, brittle strain, tectonic overpressure, and earthquake nucleation.&lt;/p&gt;

Sign in / Sign up

Export Citation Format

Share Document