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1

Methiini and Oemini of Hispaniola (Coleoptera: Cerambycidae: Cerambycinae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

Two new species of Methiini (Tessaropa hispaniolae Lingafelter, Methia dolichoptera) (Coleoptera: Cerambycidae) from Hispaniola are diagnosed, described, and illustrated. The Dominican Republic represents a New Country Record for Malacopterus tenellus (Fabricius) (Oemini), and all hispaniolan local...

2

Complementary areas for conserving avian diversity on Hispaniola  

Microsoft Academic Search

Hispaniola has been identified as a global priority for avian conservation. However, little quantitative information has been available to help guide optimal strategies for conservation action on the island. Here, the first broad-scale look has been assembled of the distribution of species of conservation concern among protected areas in Haiti and the Dominican Republic and their occurrences have been analysed

Steven C. Latta

2005-01-01

3

Ancient lithospheric source for Quaternary lavas in Hispaniola  

NASA Astrophysics Data System (ADS)

Fragments of ancient continental lithosphere, entrained in the shallow oceanic mantle, have been found in a number of locations in the Southern Hemisphere, including rare arc settings. Lavas erupted in these locations exhibit Pb isotopic characteristics that are similar to the so-called enriched mantle 1 reservoir, one of the end-members that define the isotopic composition of the Earth's mantle. However, no lavas with isotopic signatures resembling enriched mantle 1 have been identified in the Caribbean region. Here we present isotopic analyses for mafic-alkaline lavas from Quaternary volcanic centres in Hispaniola. We identify unusual isotopic characteristics indicating the presence of a mantle component similar to enriched mantle 1 beneath Hispaniola. Furthermore, we find evidence for an involvement of this mantle component in the genesis of spatially associated calk-alkaline lavas. On the basis of these isotopic systematics we estimate that the mafic-alkaline lavas are derived from an ancient lithospheric fragment with affinities to the supercontinent Gondwana. We conclude that the fragment originated from the Grenvillian terranes of Central America and Mexico, which also have affinities to Gondwana, indicating that Hispaniola interacted tectonically with these terranes.

Kamenov, George D.; Perfit, Michael R.; Lewis, John F.; Goss, Adam R.; Arévalo, Ricardo; Shuster, Robert D.

2011-08-01

4

Active Faults in Eastern Hispaniola: The Hispaniola-Puerto Rico Microplate Boundary?  

NASA Astrophysics Data System (ADS)

An extensive tract of limestone of mostly Pleistocene-Recent age covers the Eastern part of the Dominican Republic. Numerous distinctive marine terraces outcrop along the southern and eastern coast, the lowest of which has been dated at about 125Ka. In the eastern area, the highest terrace is about 50m asl, is very variable in elevation, and correlates with a terrace of about 50 m asl along the southern coast. This feature might correlate with a feature of similar height on the Island of Marie Galante in the Lesser Antilles, dated at 250Ka. Manipulation of 3 arc-sec grid of SRTM land data and a 12 arc-sec grid of marine data reveals the location of the upper marine terrace as well as numerous scarps with 10's of meters of relief tending WNW across the region. The 2nd derivative of the relief grid is used to objectively identify the location of the upper terrace, which is compared to the elevation grid to develop an along escarpment profile of terrace elevation. If undisturbed, this feature should be contour parallel, that is all at the same elevation. Systematic elevation changes along profile suggest titling and numerous abrupt vertical (~30-50m) and at least one horizontal offset (375m) of this feature. Terrace displacing scarps can be traced many kilometers from offshore, across the coast paralleling marine terraces, and continuing inland as linear features that I interpret as active normal faults cutting the limestone platform. Five systems of normal faults have been identified in this manner, the longest of which may be capable of generating earthquakes of about magnitude 7-7 1/4. If the age of the upper terrace is roughly about 250Ka, then the observed horizontal displacements of about 375 meters suggest a rate of fault motion on the order of mm"s/yr for each of the5 faults. This total rate of deformation of several mm/yr is similar to the rate of deformation calculated from GPS studies for the rate of motion between the Hispaniola and Puerto Rico microplates, suggesting that much of the inter-microplate motion is not contained to the offshore regions of the Mona Passage, but rather passes on shore in the eastern part of the Dominican Republic.

McCann, W. R.

2007-12-01

5

Mercury concentrations in tropical resident and migrant songbirds on Hispaniola.  

PubMed

Despite growing concerns over mercury (Hg) exposure to humans and wildlife on a global scale, little is known about Hg bioaccumulation in the New World tropics. From 2005 to 2011, we monitored Hg concentrations in blood of nine avian species occupying a geographic range of tropical wet broadleaf sites on the island of Hispaniola, including eight passerines (two Nearctic-Neotropical migrant and six resident species) and one top order predatory accipiter. Invertivorous songbirds were further differentiated by foraging guild, with six species of ground-foragers and two species of foliage-gleaners. Blood Hg concentrations were orders of magnitude higher in birds sampled in central and southern cloud forest sites (1,000-1,800 m elevation) than in northern and northeastern rainforest sites (50-500 m elevation), with migratory and resident species both showing 2-20× greater blood Hg concentrations in cloud forests than in rainforests. Within cloud forest sites, ground-foraging species had higher Hg concentrations than foliage-gleaning species. Top order predatory sharp-shinned hawks (Accipiter striatus) had the highest blood Hg concentrations among all species, suggesting that Hg biomagnification is occurring in terrestrial forests of Hispaniola. Two migrant songbird species overwintering on the island had higher blood Hg concentrations than have been recorded on their North American breeding grounds. Future studies should seek to elucidate sources of variation in atmospheric Hg deposition on Hispaniola and to quantify the dynamics of Hg cycling in tropical forest ecosystems, which may differ in important ways from patterns documented in temperate forest ecosystems. PMID:23076839

Townsend, Jason M; Rimmer, Christopher C; Driscoll, Charles T; McFarland, Kent P; Iñigo-Elias, Eduardo

2012-10-18

6

Carbonate platforms along the Bahama-Hispaniola collision zone  

SciTech Connect

During July 1989 a SEAMARC II seismic reflection profile survey was conducted around the deep-water margins of carbonate platforms along the North American-Caribbean plate boundary where the southeast Bahamas are actively colliding with Hispaniola. Results indicate that the small, isolated carbonate banks of the southeast Bahamas are clearly remnants of once-larger platforms. A variety of processes appear to be responsible for the retreat of these platforms. Backstepping has resulted in the majority of retreat producing a single, large deep-water plateau along the northern margin of the southeast Bahamas and a series of deepwater, steplike terraces to the south that may be fault related. SEAMARC side-scan images have also defined spectacular, large-scale scalloped margins as well as well-developed upper gullied slopes which appear to be responsible for continued gradual retreat. Well-defined avalanche chutes, which may be the result of periodic collapse, extend down the deep margin of northern Silver Bank, funneling large volumes of debris over the Bahama Escarpment. The retreating nature of the isolated southeast Bahama Banks, located in a tectonicaily active setting, contrast sharply with the large, coalesced banks of the more passive northwest Bahamas.

Mullins, H.T.; Andersen, B.C. (Syracuse Univ., NY (USA)); Dolan, J.F. (Geological Survey, Menlo Park, CA (USA)); Breen, N.A. (Lamont-Doherty Geological Observatory, Palisades, NY (USA))

1990-05-01

7

Plate boundary readjustment in oblique convergence: Example of the Neogene of Hispaniola, Greater Antilles  

Microsoft Academic Search

The Haitian fold-and-thrust belt is the major mountain belt of Haiti (western part of Hispaniola, Greater Antilles) and resembles a compressive restraining bend between the two major faults which have driven the opening of the Cayman Basin since the Eocene. During the rifting stage, from the middle to the late Eocene, this area underwent an extensional evolution with fissural volcanic

Manuel Pubellier; Alain Mauffret; Sylvie Leroy; Jean Marie Vila; Helliot Amilcar

2000-01-01

8

Historical perspective on seismic hazard to Hispaniola and the northeast Caribbean region  

NASA Astrophysics Data System (ADS)

We evaluate the long-term seismic activity of the North-American/Caribbean plate boundary from 500 years of historical earthquake damage reports. The 2010 Haiti earthquakes and other earthquakes were used to derive regional attenuation relationships between earthquake intensity, magnitude, and distance from the reported damage to the epicenter, for Hispaniola and for Puerto Rico and the Virgin Islands. The attenuation relationship for Hispaniola earthquakes and northern Lesser Antilles earthquakes is similar to that for California earthquakes, indicating a relatively rapid attenuation of damage intensity with distance. Intensities in Puerto Rico and the Virgin Islands decrease less rapidly with distance. We use the intensity-magnitude relationships to systematically search for the location and intensity magnitude MI which best fit all the reported damage for historical earthquakes. Many events occurred in the 20th-century along the plate-boundary segment from central Hispaniola to the NW tip of Puerto Rico, but earlier events from this segment were not identified. The remaining plate boundary to the east to Guadeloupe is probably not associated with M > 8 historical subduction-zone earthquakes. The May 2, 1787 earthquake, previously assigned an M 8-8.25, is probably only MI 6.9 and could be located north, west or SW of Puerto Rico. An MI 6.9 earthquake on July 11, 1785 was probably located north or east of the Virgin Islands. We located MI < 8 historical earthquakes on April 5, 1690, February 8, 1843, and October 8, 1974 in the northern Lesser Antilles within the arc. We speculate that the December 2, 1562 (MI 7.7) and May 7, 1842 (MI 7.6) earthquakes ruptured the Septentrional Fault in northern Hispaniola. If so, the recurrence interval on the central Septentrional Fault is ˜300 years, and only 170 years has elapsed since the last event. The recurrence interval of large earthquakes along the Hispaniola subduction segment is likely longer than the historical record. Intra-arc M ? 7.0 earthquakes may occur every 75-100 years in the 410-km-long segment between the Virgin Islands and Guadeloupe.

ten Brink, Uri S.; Bakun, William H.; Flores, Claudia H.

2011-12-01

9

Three new species of Canthonella Chapin from Hispaniola, with new records and Nomenclatural changes for West Indian dung beetles (Coleoptera: Scarabaeidae: Scarabaeinae)  

Microsoft Academic Search

Three new species, Canthonella jarmilae, Canthonella quesquaya, and Canthonella sikesi NEW SPECIES, are described from Hispaniola. New distribution records for Canthochilum taino Matthews and Canthonella parva Chapin expand the known range of these Puerto Rican Bank species to the northern Virgin Islands. Colonization by the Old World species Digitonthophagus gazella (Fabricius) on Jamaica, Hispaniola, Puerto Rico, St. Croix, St. Kitts,

MICHAEL A. IVIE; T. KEITH PHILIPS

10

Cenozoic tectonics of the Caribbean: Structural and stratigraphic studies in Jamaica and Hispaniola  

NASA Astrophysics Data System (ADS)

Structural and stratigraphic field studies in Jamaica and Hispaniola (Dominican Republic and Haiti) and synthesis of published data from surrounding areas refine previously proposed models for convergent and strike-slip plate interactions in the northern Caribbean. Specifically: (1) new data and regional stratigraphic analysis of major unconformities in the Greater Antilles supports the idea of two distinct arcs that terminated by collision at slightly different times in the latest Cretaceous and Paleogene; (2) field studies in the Port Maria area of northeastern Jamaica essentially complete mapping of the Wagwater Belt, a reactivated Paleogene graben and overlying sedimentary basin; and (3) the interpretation of satellite imagery and aerial photographs and field studies in the Enriquillo Valley and Sierra el Numero, Dominican Republic; the Culde-Sac Valley and southern peninsula of Haiti; and the Clydesdale area of eastern Jamaica.

Mann, W. P.

11

Plume mantle source heterogeneity through time: Insights from the Duarte Complex, Hispaniola, northeastern Caribbean  

NASA Astrophysics Data System (ADS)

Located in the Cordillera Central of Hispaniola, the Duarte Complex offers an opportunity to study an on-land fragment of the Caribbean-Colombian oceanic plateau. Geochemical, Sr-Nd isotope, and 40Ar-39Ar radiometric age data combined with detailed mapping have shown that the Duarte Complex includes two lithostratigraphic units, composed of four geochemical groups of metavolcanic rocks: Group Ia, low-Ti high-Mg basalts, and group Ib, high-Ti picrites and primitive high-Mg basalts, occur interlayered in the lowermost levels of the lower unit; group II, light rare earth element (LREE)-enriched picrites, ferropicrites and high-Mg basalts, forms the main lava sequence of the lower unit; and group III, LREE-enriched Fe-Ti basalts, is present exclusively in the upper unit. Nd isotope and incompatible trace element patterns are diverse in the Duarte Complex metavolcanics and are consistent with mantle sources related to a heterogeneous plume. Mantle melt modeling suggests that an early, extensive melting (10-20%) of shallow mantle resulted in the formation of relatively depleted group I and II magmas, whereas the late, more enriched group III magmas were the product of deeper, low-degree (<3%) melting of a heterogeneous plume. Therefore plume mantle sources were more enriched and deeper through time. Foliated amphibolites of the Duarte Complex yield 40Ar-39Ar hornblende plateau ages of 93.9 ± 1.4 and 95.8 ± 1.9 Ma (Cenomanian, 99.6-93.5 Ma) that demonstrate an older age of the protholiths, probably Albian (>96 Ma). Hence an Early Cretaceous phase of the Caribbean-Colombian oceanic plateau construction is recorded in Hispaniola.

Escuder-Viruete, Javier; PéRez-Estaún, AndréS.; Contreras, Fernando; Joubert, Marc; Weis, Dominique; Ullrich, Thomas D.; Spadea, Piera

2007-04-01

12

MultiChannel Seismic Images of Neogene Rifting in the Northern Mona Passage Between Puerto Rico and Hispaniola  

Microsoft Academic Search

Highly oblique (70°) convergence is occurring along the northeastern North America-Caribbean plate boundary offshore northern Puerto Rico and the Virgin Islands. Complicating the tectonic setting is the oblique collision of the 20 km-thick SE Bahamas carbonate platform that impedes the northeasterly movement of Hispaniola, leaving Puerto Rico and the Virgin Islands to separate along north-trending extensional structures in the Mona

S. A. Mondziel; N. R. Grindlay; P. Mann; A. Escalona

2006-01-01

13

Anomalous Alkali-Olivine Basalts Associated with Arc-related Late Cenozoic Volcanism in Southern Hispaniola  

NASA Astrophysics Data System (ADS)

Several eruptive centers of Pliocene-Quaternary age occur across southern Hispaniola that constitutes the youngest land-based magmatic activity in the Greater Antilles. Two main rock suites can be delineated based on petrography, geochemistry and location. The older larger centers in the Dominican Republic (DR) consist of basalts (45.81-53% SiO2 with TiO2 <1.2%), basaltic andesites and trachybasalts (54-55% SiO2) and trachyandesites (56-62% SiO2). These constitute a consanguineous high-K calc-alkaline (CA) series. Younger centers of Quaternary age (all probably < 1.0 Ma) occur to the west in Haiti, at San Juan de la Maguana (DR) and two small centers to the south of Yayas de Viajama (DR). The rocks are alkali-olivine basalts, limburgites and nephelenites (38.6-47.6% SiO2 with TiO2 >1.7 at MgO<12%) and are termed the mafic alkaline (MA) series. Although there is an overall similarity in the trace and minor element patterns of normalized multi-element plots of the rocks samples the CA series shows distinct depletions in the HFS elements Ta, Nb, Hf, Zr, and Ti compared to lavas in the MA series. MA series samples exhibit strong enrichment in LREE (Ce/Ybn = > 30) compared to the CA series basalts (Ce/Ybn = < 30) and greater HREE depletions. The CA suite has higher 143Nd/144Nd (0.51286 ? 0.5126) and lower 87Sr/86Sr (0.7040 ? 0.7053) than the MA suite (0.5126-0.51196; 0.7063- 0.7078). MA series lavas have unusually non-radiogenic Pb isotopic values (206Pb/204Pb < 17.9) whereas the CA suite has low but values more typical of the Greater Antilles. Incompatible trace element ratios such as Ba/Nb, Sr/Nd, Ce/Yb and Ba/La are well correlated with isotopes but the data form near continuous arrays suggesting mixing between sources. The data suggest the young alkaline lavas are derived from enriched mantle source similar to EM1 but that they are also mixing with a component reflected in the composition of the CA series that is related to previous subduction- related enrichment of the sub-arc mantle beneath Hispaniola. The presence of an EM1 component in the Greater Antilles has not been previously recognized and is unusual for an arc environment.

Lewis, J.; Perfit, M. R.; Kamenov, G.

2006-12-01

14

Egg rejection behavior in a population exposed to parasitism: Village Weavers on Hispaniola  

USGS Publications Warehouse

In contrast to African Village Weavers (Ploceus cucullatus) that are parasitized by Diederik Cuckoos (Chrysococcyx caprius), introduced weavers on Hispaniola existed without parasitism for at least 2 centuries until the arrival of the Shiny Cowbird (Molothrus bonariensis) in the 1970s. Cruz and Wiley (1989) found that Hispaniolan weavers had a lower rejection rate of foreign eggs than African populations. Subsequently, Robert and Sorci (1999) and Lahti (2005, 2006) found that acceptance of dissimilar eggs is not characteristic of the species throughout its Hispaniolan range. In 1999-2002, we studied egg rejection in Hispaniolan weavers on a broad regional scale. Rejection increased as experimental eggs became increasingly different from the host eggs. Rejection rates for mimetic eggs, different color eggs, different-spotting eggs, and cowbird eggs was 23.2%, 33.3%, 61.5%, and 85.3%, respectively, with higher rejection of cowbird eggs in areas where cowbirds were observed. Although rejection is likely to have a genetic component, the differences could be due to phenotypic plasticity. Plasticity in egg rejection may be expected, given the potential cost of rejection and the spatiotemporal distribution of cowbirds. Thus, egg rejection has not necessarily decreased in Hispaniolan weavers, but it may act in a plastic manner, increasing where cowbirds are present. ?? The Author 2008. Published by Oxford University Press on behalf of the International Society for Behavioral Ecology. All rights reserved.

Cruz, A.; Prather, J. W.; Wiley, J. W.; Weaver, P. F.

2008-01-01

15

Significant earthquakes on the Enriquillo fault system, Hispaniola, 1500-2010  

NASA Astrophysics Data System (ADS)

Although the 2010 Haiti earthquake came as a surprise to many, historical records indicate frequent seismic activity along the northeast Caribbean plate boundary over the past 500 years, particularly on the island of Hispaniola. Here we show that a series of devastating earthquakes on the Enriquillo fault system in the 18th century started with an intensity magnitude (MI) of 6.8 earthquake in 1701 near the location of the 2010 Haiti earthquake and that the accounts of the shaking in the 1701 earthquake are similar to those of the 2010 earthquake. A series of large earthquakes migrating from east to west started with the October 18, 1751 MI7.6 earthquake near the eastern end of the fault in the Dominican Republic, followed by the November 21, 1751 MI6.7 earthquake near Port-au-Prince, Haiti, and the June 3, 1770 MI7.7 earthquake west of the 2010 earthquake rupture. We associate no other significant events since 1500 with the Enriquillo fault system. The 2010 Haiti earthquake may mark the beginning of a new cycle of large earthquakes on the Enriquillo fault system after 240 years of quiescence. Future devastating earthquakes should be expected.

Bakun, W.; Flores, C. H.; ten Brink, U. S.

2010-12-01

16

Three new phylogenetic and biological Neurospora species: N. hispaniola, N. metzenbergii and N. perkinsii.  

PubMed

The recent recognition of provisional Neurospora phylogenetic species (PS) 1-3 gave us the opportunity to compare genetic isolation, which underlies phylogenetic species recognition (PSR), with reproductive isolation as criteria for recognizing new species. This investigation involved first finding new individuals of PS 1-3 from a search of the Perkins culture collection, then assessing genetic isolation by PSR for old and new members of PS 1-3 and finally comparing species recognition by genetic isolation as determined by PSR to species recognition by reproductive isolation as determined by biological species recognition (BSR) and geographic distribution. To aid the search for additional members of the PS we used the genetic variation originally used to discover Neurospora PS 1-3 to easily distinguish members of Neurospora PS 1-3 from the closely related species N. crassa and N. intermedia. To increase our chance of success the analysis was performed on N. crassa and N. intermedia isolates that were either not clearly assignable to species by BSR using tester strains or were from the same geographic locations as the known members of PS1-3. Eleven new members of Neurospora PS 1-3 were identified: one new PS1, nine new PS2 and one new PS3. To complement PSR we investigated reproductive isolation with BSR in PS1-3 and the two other most closely related species, N. intermedia and N. crassa, with intraspecific and interspecific crosses. PS1 and PS2 appear reproductively isolated because they successfully mated intraspecifically and not interspecifically. PS3 isolates successfully crossed with other PS3 isolates, however they also successfully crossed with N. crassa, as previously reported, indicating that genetic isolation can precede reproductive isolation. We compared phylogenetic, mating and geographical data to challenge the use of PSR as the main criterion in the formal description of species and, having failed to discredit the approach, describe the new species, N. hispaniola (PS1), N. metzenbergii (PS2) and N. perkinsii (PS3). PMID:19927744

Villalta, Christopher F; Jacobson, David J; Taylor, John W

17

A new atlantasellid isopod (Asellota: Aselloidea) from the flooded coastal karst of the Dominican Republic (Hispaniola): evidence for an exopod on a thoracic limb and biogeographical  

Microsoft Academic Search

A new representative of the thus far monotypic, Bermudan aselloid family Atlantasellidae is described from the freshwater layers of two coastal sinkholes on the south-west Dominican Republic, Hispaniola. Atlantasellus dominicanus sp. nov. is extraordinary among isopods in retaining a remnant of the exopod on one of its pereiopods; no other isopod is known to express a schizopodous condition of thoracic

Miquel Marques

18

First New World Documentation of an Old World Citrus Pest, the Lime Swallowtail Papilio demoleus (Lepidoptera: Papilionidae), in the Dominican Republic (Hispaniola)  

Microsoft Academic Search

Papilio demoleus L., a well-known citrus pest in the Old World, is documented from eastern Dominican Republic on the Ca- ribbean island of Hispaniola. Resumen. Se registra la especie Papilio demoleus, una reconocido plaga de los citricos en el Mundo Viejo,

Kelvin A. Guerrero; Denia Veloz; Sarah Lyn Boyce; Brian D. Farrell

19

Tree-based delimitation of morphologically ambiguous taxa: a study of the lizard malaria parasites on the Caribbean island of Hispaniola.  

PubMed

Malaria parasites in the genus Plasmodium have been classified primarily on the basis of differences in morphology. These single-celled organisms often lack distinguishing morphological features, and this can encumber both species delimitation and identification. Six saurian malaria parasites have been described from the Caribbean island of Hispaniola. All six infect lizards in the genus Anolis, but only two of these parasites can be distinguished using morphology. The remaining four species overlap in morphology and geography, and cannot be consistently identified using traditional methods. We compared a morphological approach with a molecular phylogenetic approach for assessing the taxonomy of these parasites. We surveyed for blood parasites from 677 Anolis lizards, representing 26 Anolis spp. from a total of 52 sites across Hispaniola. Fifty-five of these lizards were infected with Plasmodium spp., representing several new host records, but only 24 of these infections could be matched to previously described species using traditional morphological criteria. We then estimated the phylogeny of these parasites using both mitochondrial (cytb and coxI) and nuclear (EF2) genes, and included carefully selected GenBank sequences to confirm identities for certain species. Our molecular results unambiguously corroborated our morphology-based species identifications for only the two species previously judged to be morphologically distinctive. The remaining infections fell into two well-supported and reciprocally monophyletic clades, which contained the morphological variation previously reported for all four of the morphologically ambiguous species. One of these clades was identified as Plasmodium floridense and the other as Plasmodium fairchildi hispaniolae. We elevate the latter to Plasmodium hispaniolae comb. nov. because it is polyphyletic with the mainland species Plasmodium fairchildifairchildi and we contribute additional morphological and molecular characters for future species delimitation. Our phylogenetic hypotheses indicate that two currently recognised taxa, Plasmodium minasense anolisi and Plasmodium tropiduri caribbense, are not valid on Hispaniola. These results illustrate that molecular data can improve taxonomic hypotheses in Plasmodium when reliable morphological characters are lacking. PMID:21718698

Falk, Bryan G; Mahler, D Luke; Perkins, Susan L

2011-06-15

20

North Caribbean neotectonic events: The Trans-Haitian fault system. Tertiary record of an oblique transcurrent shear zone uplifted in Hispaniola  

Microsoft Academic Search

Pubellier, M., Vila, J.-M. and Boisson, D., 1991. North Caribbean neotectonic events: The Tram-Haitian fault system. Tertiary record of an oblique shear zone uplifted in Hispaniola. In: J. Fourniguet and G. Pierre (Editors). Neotectonics. Tectonophysics, 194: 217-236. The left-lateral relative motion between the Caribbean and the North American plates has previously been inferred as occurring along a fault zone located

M. Pubellier; J.-M. Vila; D. Boisson

1991-01-01

21

On the role of the Beata Ridge in the structure of southern Hispaniola: new constrains from the correlation between offshore and onshore structures  

NASA Astrophysics Data System (ADS)

The Beata Ridge is a thickened aseismic crust block that forms a NNE-SSW trending bathymetric high located in the interior of the Caribbean Large Igneous Province (CLIP). This ridge is impinging into the Greater Antilles island arc in south-central Hispaniola Island. The impingement has resulted into the following main consequences for the southern region of Hispaniola: uplifting and accretion of part of the CLIP to the island arc, an associated localized strain partitioning and a sharp structural change between both sides of the ridge, with frontal thrusting in the Los Muertos convergent margin (to the east) against dominant left-lateral strike-slip tectonics in the Enriquillo-Plantain Garden fault zone (to the west). Two hypotheses have been suggested to explain the impingement as a result of: 1) the continuous motion of the aseismic ridge toward the NE against the Greater Antilles, at least from the Miocene; or 2) the thickened ridge acting as a fixed obstacle in the foreland area impeding the overthrusting of the island arc over the Caribbean plateau. Several works have tried to restore the situation prior to the impingement of the Beata Ridge into the island arc and to correlate the tectonic units observed on both sides of the region of impingement: the offshore imbricate structures observed in Los Muertos convergent margin with the onshore Peralta fold-and-thrust belt and/or the E-W transcurrent Enriquillo fault system in southern Hispaniola. However as a result of the huge lateral and vertical offset caused by the impingement of the aseismic ridge there is not a tectonic model which can successfully explain this transition. A detailed interpretation of the deep and shallow structure of western Los Muertos convergent margin and northern Beata Ridge has been made using the new data obtained from the CARIBENORTE research cruise carried out in the spring of 2009 in the southern insular slope of Hispaniola. On the other hand a complete geothematic survey of the whole Dominican Republic funded by the EU Sysmin Program has been recently performed including (among others) a detailed 1:50.000 geological and 1:100.000 geomorphological and active processes mappings. The integration and correlation of the onshore and offshore structural data of southern Hispaniola presented here provides valuable information to constrain and evaluate the consequences of the impingement of the Beata Ridge into the island arc and to help understand how the present day sharp transition between frontal thrusting and strike-slip tectonics may take place. These results can be further implemented into the evaluation and assessment of seismic hazard in the densely populated Hispaniola island, and especially, the eastern termination of the Enriquillo-fault zone, that in Haiti was responsible for the deadly event on 12 January 2010.

Granja Bruña, J.; Hernaiz-Huerta, P.; Carbó-Gorosabel, A.; Llanes Estrada, M.; Pérez-Valera, F.; Abad, M.; Gómez Ballesteros, M.; Druet, M.; Munoz Martin, A.; Martín-Dávila, J.; Pazos, A.; Catalan, M.; ten Brink, U. S.

2011-12-01

22

New myrmecomorphous longhorned beetles from Haiti and the Dominican Republic with a key to Anaglyptini and Tillomorphini of Hispaniola (Coleoptera, Cerambycidae, Cerambycinae)  

PubMed Central

Abstract First records of the tribes Anaglyptini and Tillomorphini (Coleoptera: Cerambycidae: Cerambycinae) are documented for Hispaniola. A new genus of a highly myrmecomorphic longhorned beetle (Licracantha gen. n.) is described and illustrated based on one species (Licracantha formicaria sp. n.) and provisionally assigned to Tillomorphini. Three other new species of ant mimic longhorned beetles are described and illustrated: Calliclytus macoris sp. n. (Tillomorphini), Tilloclytus baoruco sp. n., and Tilloclytus neiba sp. n. (Anaglyptini). An identification key and distribution map to all known Hispaniolan species of these two tribes are presented.

Lingafelter, Steven W.

2011-01-01

23

New records of Caribbomerus from Hispaniola and Dominica with redescription of C. elongatus (Fisher) and a key to species of the genus in the West Indies (Coleoptera, Cerambycidae, Cerambycinae, Graciliini)  

PubMed Central

Abstract Three species of Caribbomerus Vitali are newly recorded for the Dominican Republic: Caribbomerus decoratus (Zayas), Caribbomerus elongatus (Fisher), and Caribbomerus asperatus (Fisher). The first two also represent first records for Hispaniola. Caribbomerus elongatus (Fisher) is redescribed based on additional material, including the first known males. Caribbomerus similis (Fisher) is newly recorded for Dominica. A key to the species of the genus from the West Indies is provided.

Lingafelter, Steven W.

2011-01-01

24

New records of Caribbomerus from Hispaniola and Dominica with redescription of C. elongatus (Fisher) and a key to species of the genus in the West Indies (Coleoptera, Cerambycidae, Cerambycinae, Graciliini).  

PubMed

Three species of Caribbomerus Vitali are newly recorded for the Dominican Republic: Caribbomerus decoratus (Zayas), Caribbomerus elongatus (Fisher), and Caribbomerus asperatus (Fisher). The first two also represent first records for Hispaniola. Caribbomerus elongatus (Fisher) is redescribed based on additional material, including the first known males. Caribbomerus similis (Fisher) is newly recorded for Dominica. A key to the species of the genus from the West Indies is provided. PMID:21594096

Lingafelter, Steven W

2011-03-11

25

Potential fields and seismicity at northern La Hispaniola Island: useful constraints to determine the crustal structure of an oblique convergence area  

NASA Astrophysics Data System (ADS)

The interpretation of aeromagnetic and gravity data together with petrophysical analysis allow characterize the tectonic domains and the determination of the crustal structure up to Moho levels. In order to compare the crustal structure deduced from the potential fields with the seismicity, a set of earthquakes events from the USGS database have been studied (hypocenters shallower than 40 km and magnitude greater than 3.5). This study is focused on the northern part of the La Hispaniola Island, where an oblique subduction and strike-slip collision is taking place since the Mesozoic. The Septentrional Fault Zone (SFZ), an almost WNW-ESE directed strike slip fault, is bounded by a set of earthquakes up to 6 in magnitude whose hypocenter is located from 20 to 30 km in depth, with some deeper events (up to 40 km) in places. Northward of this fault zone, there is an area of mainly shallower hypocenters (up to 20 km) characterized by events of comparatively higher magnitude (up to 7) that deepen slightly again towards offshore where the range of depths is 0 to 30 km clustering around what is believed to be the subduction zone. The Bouguer anomaly shows a sharp gradient that separates the Cibao Valley to the south, characterized by an elongated minimum, from the accretionary prism (Mamey group and Puerto Plata-Rio San Juan Complex) to the north, characterized by a set of relative maxima and minima of higher intensity. Moreover, the accretionary prism presents a well defined magnetic zonation over the Mamey Group and the igneous-metamorphic complexes of Puerto Plata and Rio San Juan. In this area, magnetic anomalies are an order of magnitude higher than in the Cibao Valley, where the magnetic fabric is rather uniform with the exception of three prominent anomalies that can be associated to igneous rocks emplaced to the northern border of La Hispaniola Fault Zone. The Camú Fault, that separates Mamey Group from Puerto Plata Complex, constitutes another clear magnetic boundary, whereas it is not so clear in terms of seismicity or gravity. The potential field data together with the location of the epicentre and hypocenter of the earthquakes helps to define the upper boundary of the subducting slab at cortical levels and the geometry of the accretionary prism, specially the igneous-metamorphic complexes of Puerto Plata and Rio San Juan.

Ayala, C.; García-Lobón, J. L.; Rey Moral, C.; Escuder-Viruete, J.

2012-04-01

26

Pliocene-Lower Pleistocene shallow-water mixed siliciclastics and carbonates (Yanigua and Los Haitises formations) in eastern Hispaniola (Dominican Republic)  

NASA Astrophysics Data System (ADS)

The virtually unfolded sedimentary cover of the Cordilleras Central and Oriental in the eastern Dominican Republic (eastern Hispaniola, tropical North Atlantic) largely consists of Pliocene to Early Pleistocene mixed siliciclastics and carbonates. These deposits have been grouped into two laterally interfingering mapping units, the Yanigua and Los Haitises formations. The former (mainly siliciclastics) comprises marl, marly limestone, and minor conglomerate, sandstone, lignite, and carbonaceous clay and crops out closest to the basement. The Los Haitises Formation mainly consists of limestone and intercalating beds of marly limestone and marl. Lithological mapping at the 1:50,000 scale and facies analysis of twelve measured sections and of additional fourteen outcrops suggest that these deposits mainly formed on a shallow-water marine platform fringing the precursor reliefs of the Cordillera Oriental and the southeastern end of the Cordillera Central. Only a limited proportion of sediment formed in floodplains and marshes. Marl and marly limestone dominated the inner platform sediments. Terrigenous mud decreased away from the emergent basement and carbonate sedimentation dominated the more external platform. Corals, molluscs, echinoids, foraminifers, bryozoans, coralline algae, and Halimeda are the main components with varying amounts of carbonate mud. The platform was generally a low-energy environment with seagrass patches. In the inner platform, corals grew as isolated colonies or as small patch reefs dominated by Porites in marly and bioclastic substrates. Branching corals (Stylophora and Acropora) grew in extensive carpets in more distal areas. At least in the last stage of its development (Early Pleistocene), the platform was rimmed by a reef barrier similar to the Holocene Caribbean barrier reefs, with Acropora gr. palmata, A. cervicornis, Porites, Montastrea, Siderastrea, and Diploria as the main reef builders.

Braga, Juan C.; Díaz de Neira, Alberto; Lasseur, Eric; Mediato, José; Aguirre, Julio; Abad, Manuel; Hernaiz-Huerta, Pedro P.; Monthel, Jacques; Pérez-Valera, Fernando; Lopera, Eusebio

2012-07-01

27

Miconia zanonii (Melastomataceae: Miconieae), a new species from Hispaniola  

Microsoft Academic Search

Miconia zanonii, which occurs in broad-leaved cloud forests at four localities in the Cordillera Central of the Dominican Republic, is described\\u000a and illustrated. It is compared withM. krugii andM. samanensis, two probably close relatives withinMiconia sect.Chaenopleura.

Walter S. Judd; James D. Skean; Reed S. Beaman

1988-01-01

28

Taxonomic studies in the Miconieae (Melastomataceae). VI. Miconia santanana, a new species from Hispaniola  

Microsoft Academic Search

Miconia santanana, which occurs in broad-leaved forests along streams of pineland habitats in the Cordillera Central of the Dominican Republic,\\u000a is described and illustrated. It is compared withM. ferruginea andM. adenocalyx, two presumed close relatives withinMiconia sect.Chaenopleura. Eco-geographic characterizations and a key are presented for these three species.

Walter S. Judd; James D. Skean

1994-01-01

29

A NEW BURROWING FROG FROM HISPANIOLA WITH COMMENTS ON THE INOPTATUS GROUP OF THE GENUS ELEUTHERODACTYLUS (ANURA: LEPTODACTYLIDAE)  

Microsoft Academic Search

Eleutherodactylus parapelates is described from the Massif de la Hotte of the Haitian Tiburon Peninsula. It is a large burrowing species that vocalizes from enclosed underground chambers and is most similar to E. hypostenor and E. ruthae. Together, these three species form a subgroup within the inoptatus group, which now contains six large Hispaniolan Eleutherodactylus.

S. BLAIR HEDGES; RICHARD THOMAS

30

Is the Caribbean plate subducting underneath Hispaniola? Preliminary results from Caribe Norte wide-angle seismic experiment  

NASA Astrophysics Data System (ADS)

A 200 km long, wide-angle seismic refraction transect was collected in the spring of 2009, across the widest part of the Muertos compressive margin (longitude 69°W). The transect was designed to test the hypothesized subduction of the Caribbean plate’s interior beneath the eastern Greater Antilles island arc. Shots were fired every 90 seconds from the R/V Hesperides’ 3850 cubic inches water-gun array, which, towed at 5 knots, resulted in a shot spacing of ~ 230 m. The seismic signal was recorded by 5 ocean-bottom seismometers deployed at distances varying from 25 to 50 km. Gravity, bathymetry and magnetic data were also acquired along that transect. Published and reprocessed reflection seismic lines nearby provided an initial model of the sediment column and on the pattern of upper crustal reflectors. Preliminary results of a 2-D forward ray-tracing model have enabled us to outline the broad-scale crustal structure across the Muertos margin. The Caribbean oceanic slab shows considerable variations in crustal thickness in the Venezuelan basin area (Caribbean plate’s interior). Farther north, the slab is imaged underneath the Muertos margin to about 60 km north of the deformation front and up to 19 km depth,. A change in crustal p wave velocity at about 60 km from the deformation front (or 70 km from the southern coast of the Dominican Republic) is interpreted to be the boundary between the arc crust and the accretionary prism. Caribbean oceanic crust does not appear to extend farther north. We interpret the results to indicate limited overthrusting of the Caribbean slab in the muertos Trough, rather than subduction.

Llanes Estrada, M.; ten Brink, U. S.; Carbo-Gorosabel, A.; Granja Bruña, J.; Flores, C. H.; Davila, J. M.; Pazos, A.; Quijano, J.

2010-12-01

31

A new species of Derancistrus (Coleoptera: Cerambycidae: Prioninae) from Dominican Republic with notes on other species of Prioninae of Hispaniola  

Technology Transfer Automated Retrieval System (TEKTRAN)

Derancistrus hovorei is described from Dominican Republic. A diagnosis is provided to discriminate it from related taxa, in particular Derancistrodes vittatus (Olivier) and Derancistrus elegans (Palisot de Beauvois). Biological, distributional, and/or taxonomic notes are provided for other Hispani...

32

Taxonomic studies in the Miconieae (Melastomataceae). II. Systematics of the miconia subcompressa complex of Hispaniola, including the description of two new species  

Microsoft Academic Search

TheMiconia subcompressa complex containsMiconia subcompressa, M. selleana, M. hypiodes, and two taxa described here:M. septentrionalis (collected mainly at Pico Diego de Ocampo, Cordillera Septentrional) andM. jimenezii (collected at high elevations in the Sierra de Neiba-Montagnes Noires). Members of the group are characterized by a shrubby\\u000a or arborescent habit; leaves densely covered with ferrugineous, stellate hairs on the abaxial surface; large,

Walter S. Judd; Reed S. Beaman

1988-01-01

33

Magmatic relationships and ages between adakites, magnesian andesites and Nb-enriched basalt-andesites from Hispaniola: Record of a major change in the Caribbean island arc magma sources  

NASA Astrophysics Data System (ADS)

Located in the Cordillera Central of the Dominican Republic, the Late Cretaceous Tireo Fm (TF) records a major change of the magma sources in the Caribbean island arc. It comprises a > 3 km thick sequence of arc-related volcanic and volcano-sedimentary rocks with variable geochemical characteristics. Combined detailed mapping, stratigraphy, geochemistry and U Pb/Ar Ar geochronology show that the volcanic rocks of the Tireo Fm include two main volcanic sequences. The lower volcanic sequence is dominated by monotonous submarine vitric lithic tuffs and volcanic breccias of andesite to basaltic andesite, with minor interbedded flows of basalts and andesites. Fossil and (U Pb and 40Ar 39Ar) geochronological data show that arc magmatism in the lower sequence began to accumulate before ˜ 90 Ma, from the Aptian to Turonian. These rocks constitute an island arc tholeiitic suite, derived from melting by fluxing of a mantle wedge with subduction-related hydrous fluids. The upper volcanic sequence is characterized by a spatial and temporal association of adakites, high-Mg andesites, and Nb-enriched basalts, which collectivelly define a shift in the composition of the subduction-related erupted lavas. A dacitic to rhyolitic explosive volcanism with subaerial and episodic aerial eruptions, and sub-volcanic emplacements of domes, characterize mainly this stratigraphic interval. The onset of this volcanism took place at Turonian Coniacian boundary and continued in the Santonian to Lower Campanian, with minor events in the Late Campanian. Adakites represent melts of the subducting slab, magnesian andesites the product of hybridization of adakite liquids with mantle peridotite, and Nb-enriched basalts melts of the residue from hybridization. We propose a model of oblique ridge subduction at ˜ 90 Ma and possibly subsequent slab window formation, as principal cause of magmatic variations recorded in the Caribbean island arc, above a southwestern-dipping subduction zone.

Escuder Viruete, J.; Contreras, F.; Stein, G.; Urien, P.; Joubert, M.; Pérez-Estaún, A.; Friedman, R.; Ullrich, T.

2007-12-01

34

Cuban parasitology in review: a revolutionary triumph.  

PubMed

Although the population of Hispaniola, Cuba's most similar neighbour in the Caribbean, continues to be threatened by parasitic diseases (including malaria), many tropical parasitic infections in Cuba have been eliminated or controlled. However, some parasitic infections remain important in the Cuban population, and the occurrence of vectors and the high possibility of introduction of parasites mean that Cuban diagnosticians must remain alert. Some key aspects of human parasitology in Cuba are reviewed here, including historical information, comparative data from Hispaniola and Jamaica, and how Cuba strives to maintain and improve its control against parasitic infections. Data from recent key novel parasitology research conducted in Cuba are also described. PMID:18723396

Rivero, Lázara Rojas; Fernández, Fidel Angel Núñez; Robertson, Lucy J

2008-08-22

35

Hispaniolan Hemilophini (Coleoptera: Cerambycidae: Lamiinae)  

Technology Transfer Automated Retrieval System (TEKTRAN)

The Tribe Hemilophini (Lamiinae) is reviewed for Hispaniola and an identification key is provided. Fifteen species are now known from the island, including one new species of Adesmus (A. fortunei from La Vega Province, Dominican Republic), one new species of Oedudes (O. anulatus from Peravia and La...

36

Historical occurrence and distribution of humpback whales in the eastern and southern Caribbean Sea, based on data from American whaling logbooks  

Microsoft Academic Search

The best-known present-day wintering areas for the North Atlantic population of humpback whales ( Megaptera novaeangliae) are in the northern West Indies, notably off the island of Hispaniola. However, it is known that in the nineteenth century American whaler s hunted humpbacks in the Windward Islands (primarily from Guadeloupe southwards), along the coast of Trinidad, in the Gulf of Paria

Randall R. Reeves; Steven L. Swartz; Sara E. Wetmore; Phillip J. Clapham

2001-01-01

37

Molecular phylogeny and biogeography of West Indian frogs of the genus Leptodactylus (Anura, Leptodactylidae)  

Microsoft Academic Search

Three endemic species of the aquatic-breeding frog genus Leptodactylus are recognized from the West Indies: Leptodactylus albilabris (Puerto Rico and the Virgin Islands), Leptodactylus dominicensis (Hispaniola), and Leptodactylus fallax (Lesser Antilles). DNA sequences were obtained from several mitochondrial genes to resolve taxonomic questions involving these species and to provide insights into their origin and distribution in the islands. We found

S. Blair Hedges; Matthew P. Heinicke

2007-01-01

38

Sweet drinks are made of this: Conservation genetics of an endemic palm species from the Dominican Republic  

Technology Transfer Automated Retrieval System (TEKTRAN)

Pseudophoenix ekmanii is a threatened palm species restricted to the Parque Nacional of Jaragua in the southernmost region of Hispaniola. Sap from individual trees is commonly extracted to make a local drink; once they are tapped the plant usually dies. Additionally, adult plants are harvested for...

39

Submarine landslide as the source for the October 11, 1918 Mona Passage tsunami: Observations and modeling  

Microsoft Academic Search

The October 11, 1918 ML 7.5 earthquake in the Mona Passage between Hispaniola and Puerto Rico generated a local tsunami that claimed approximately 100 lives along the western coast of Puerto Rico. The area affected by this tsunami is now significantly more populated. Newly acquired high-resolution bathymetry and seismic reflection lines in the Mona Passage show a fresh submarine landslide

A. M. López-Venegas; E. L. Geist

2008-01-01

40

Assessing the dendrochronological potential of Pinus occidentalis Swartz in the Cordillera Central of the Dominican  

Microsoft Academic Search

Opportunities for dendrochronology in the tropics are rare because few locations experience sea- sonality strong enough to induce annual (or even dependably cyclic) ring formation in trees. Consequently, any such opportunities that exist are valuable and identifying them is worth investing time and effort. West Indian pine (Pinus occidentalis Swartz) is endemic to the island of Hispaniola (19? N, 71?

James H. Speer; Kenneth H. Orvis; Henri D. Grissino-Mayer; Lisa M. Kennedy; Sally P. Horn

2004-01-01

41

Transcending imaginations through football participation and narratives of the other: Haitian national identity in the Dominican Republic  

Microsoft Academic Search

Reflexive narratives aim to produce new knowledge regarding some social or cultural phenomena. This paper explores the Haitian national identity from the perspective of a volunteer tourist and football participant. Although football first arrived to the Dominican Republic prior to World War II, the game's influence increased as Haitians moved across the national border that divides the island of Hispaniola.

Nicholas Wise

2011-01-01

42

NASA Airborne Radar To Study Quake Faults In Haiti, Dominican Republic  

NASA Website

In response to the disaster in Haiti on Jan. 12, NASA has added a series of science overflights of earthquake faults in Haiti and the Dominican Republic on the island of Hispaniola to a previously scheduled three-week airborne radar campaign to ...

43

Conservation and management of the American crocodile  

Microsoft Academic Search

The American crocodile is a rare and endangered species, the range of which has contracted to disjunct locations such as Hispaniola, Jamaica, Cuba, Panama, and southern Florida. In an attempt to determine what factors might be limiting population growth, an extensive collaborative research program was conducted in 1978–82 in southern Florida. Limiting factors explicitly studied included climate, hurricanes, population dispersion,

James A. Kushlan

1988-01-01

44

Overview and descriptions of caddisflies (Insecta, Trichoptera) in Dominican amber (Miocene)  

Microsoft Academic Search

In this paper, nine new fossil species of Trichoptera in Dominican amber are described: An- tillopsyche auricula n. sp., Antillopsyche digitus n. sp., Atopsyche perlucida n. sp., Calosopsyche palaeoelegans n. sp., Cernotina pulchra n. sp., Chimarra (Chimarrita) palaenova n. sp., Cubanoptila longiscapa n. sp., Macronema hispaniola n. sp., Phylloicus velteni n. sp. Thus 31 fossil species are verified in Dominican

WILFRIED WICHARD

45

First Caribbean Floricomus (Araneae: Linyphiidae), a new fossil species in Miocene Dominican Republic amber. A new synonymy for the extant North American fauna  

Microsoft Academic Search

The new species Floricomus fossilis (Araneae: Linyphiidae) is described from Miocene Dominican Republic amber. This is the first fossil record of Floricomus, extending its known geological range by 15–20 Ma, and is the first record of the genus outside North America and Canada. Extant species may exist on Hispaniola, given the similarities between the known fossil and extant faunas. Most

David Penney

2005-01-01

46

Establishment of the west indian fruit fly (Diptera: Tephritidae) parasitoid Doryctobracon areolatus (Hymenoptera: Braconidae)in the Dominican Republic  

Technology Transfer Automated Retrieval System (TEKTRAN)

The West Indian fruit fly, Anastrepha obliqua (Macquart), infests numerous fruit species, particularly Anacardiaceae and most importantly mango (Mangifera indica L.). Widespread in the Neotropics, it was first reported in Hispaniola nearly 70 years ago. Continental populations are attacked by the op...

47

THE AFRICAN CLUSTER BUG, AGONOSCELIS PUBERULA STAL (HETEROPTERA: PENTATOMIDAE), ESTABLISHED IN THE NEW WORLD  

Technology Transfer Automated Retrieval System (TEKTRAN)

An African species of Pentatomidae, Agonoscelis puberula Stal, is reported for the first time from Mexico, the southern United States, and the Islands of Jamaica and Hispaniola, where it has now established. The oldest western hemisphere record dates from 1985. This species has gone unrecognized p...

48

The dynamics of intra-oceanic subduction zones: A direct comparison between fossil petrological evidence (Rio San Juan Complex, Dominican Republic) and numerical simulation  

Microsoft Academic Search

Dispersed blocks of various types of metamorphic rocks in serpentinite mélanges of the northern Dominican Republic (Hispaniola) provide fossil evidence for the dynamics of the subduction zone channel in the intra-oceanic Caribbean subduction zone system between 120 and 55 Ma. Comprehensive petrological and geochronological data on three exemplary samples of eclogite and blueschist are presented that allow a series of different

M. Krebs; W. V. Maresch; H.-P. Schertl; C. Münker; A. Baumann; G. Draper; B. Idleman; E. Trapp

2008-01-01

49

NASA Imagery of Haiti  

NSDL National Science Digital Library

This page includes a collection of NASA images surrounding the Haiti Earthquake. Images include landslide risk maps, photos from the Terra Spacecraft, post-earthquake Port au Prince, Hispaniola topography map, anaglyph (3-D) map of southern Haiti, and 3-D topography of Port au Prince.

Nasa

50

THE CARAVEL PROJECT: THE LOCATION, DESCRIPTION, AND RECONSTRUCTION OF MARINE SITES THROUGH REMOTE VIEWING, INCLUDING A COMPARISON WITH AERIAL PHOTOGRAPHY,GEOLOGIC CORING, AND ELECTRONIC REMOTE SENSING  

Microsoft Academic Search

The Columbus Caravels Project is a multi-phase research program designed to locate and excavate from St. Ann's Bay, Jamaica the remains of Columbus' last two ships, Capitana and Santiago de Palos. After an enforced exile of a year and five days, Columbus and his marooned crew were finally rescued on 29 June 1504. They departed for Hispaniola and Spain, leaving

Stephan A. Schwartzi; Randall J. De Matteiii; Roger C. Smithiii

51

Consequences of Technology Transfer in the Pueblo Viejo Gold Mine  

Microsoft Academic Search

HE DOMINICAN REPUBLIC is a small Caribbean nation that shares the island of Hispaniola with Haiti. According to the U.S. Bureau of Mines (1986), there are vast gold reserves in the Cotui region of the Dominican Republic. Gold mining at Pueblo Viejo came to an abrupt halt when the mine was closed because of technical and financial considerations in June

Ramon Fernandez-Caamano; Scott D. Johnson

2005-01-01

52

Phylogenetics, conservation, and historical biogeography of the West Indian members of the Adelieae (Euphorbiaceae)  

Microsoft Academic Search

The Caribbean Island Biodiversity Hotspot is the largest insular system of the New World and a priority for biodiversity conservation worldwide. The tribe Adeliae (Euphorbiaceae) has over 35 species endemic to this hotspot, representing one of the most extraordinary cases of speciation in the West Indies, involving taxa from Cuba, Hispaniola, Jamaica, and the Bahamas. These species form a monophyletic

Brett Jestrow

2010-01-01

53

Phylogenetics, Conservation, and Historical Biogeography of the West Indian Members of the Adelieae (Euphorbiaceae)  

Microsoft Academic Search

The Caribbean Island Biodiversity Hotspot is the largest insular system of the New World and a priority for biodiversity conservation worldwide. The tribe Adeliae (Euphorbiaceae) has over 35 species endemic to this hotspot, representing one of the most extraordinary cases of speciation in the West Indies, involving taxa from Cuba, Hispaniola, Jamaica, and the Bahamas. These species form a monophyletic

Brett Jestrow

2010-01-01

54

Hope for Haiti: An analysis of Facebook and Twitter usage during the earthquake relief efforts  

Microsoft Academic Search

The Haitian earthquake devastated the small island of Hispaniola, leaving thousands dead and billions of dollars in property damage. The earthquake also ignited a firestorm of social media use by organizations. By applying framing theory to the analysis of Facebook posts and tweets sent by nonprofits and media organizations, this study discovered differences between nonprofits and media in terms of

Sidharth Muralidharan; Leslie Rasmussen; Daniel Patterson; Jae-Hwa Shin

2011-01-01

55

RELIQUIAE DILUVIANAE ALTER: LAST INTERGLACIAL FLOOD DEPOSITS IN THE CAVES OF THE WEST INDIES  

Microsoft Academic Search

1. ABSTRACT Recent efforts to extend the terrestrial vertebrate record of the West Indies have resulted in the discovery of distinctive last-interglacial (Sangamonian) cave deposits on the islands of Jamaica, Puerto Rico, Hispaniola, and Anguilla. Each of these deposits apparently represents debris (including vertebrate bone) emplaced by catastrophic flooding during last-interglacial time. These are currently the only dated West Indian

Donald A. McFarlane; Joyce Lundberg

56

Molecular systematics of Hispaniolan pupfishes (Cyprinodontidae: Cyprinodon): implications for the biogeography of insular Caribbean fishes.  

PubMed

We used sequence variation in the mtDNA control-region and ND2 and cyt b genes to assess the systematics and biogeography of the five species of pupfish (Cyprinodon) on Hispaniola. These include four endemics, the relatively large-bodied Cyprinodon bondi, Cyprinodon nichollsi, and Cyprinodon sp., each from a separate lake in southwestern Hispaniola, and Cyprinodon higuey from a coastal lake in eastern Hispaniola. The fifth species consists of coastal populations referable to Cyprinodon variegatus riverendi. The results indicate that Hispaniola has been invaded by at least two forms, first by a late Pliocene progenitor of Cyprinodon variegatus ovinus and the large-bodied Hispaniolan species, and, more recently, by one or more ancestral forms allied with Cyprinodon variegatus variegatus and C. v. riverendi. Levels of divergence indicate that large expanses of open sea have not acted as long-term barriers to inter-island dispersal of cyprinodontiform fishes. This study, together with the molecular systematics of other insular Caribbean fishes, indicates that most insular groups originated from late Neogene dispersal from the mainland. The patterns of mtDNA variation in Cyprinodon showed little congruence with the species/subspecies taxonomy. PMID:16442312

Echelle, Anthony A; Fuselier, Linda; Van Den Bussche, Ronald A; Rodriguez, Carlos M L; Smith, Michael L

2006-01-25

57

Hispaniolan hemilophini (coleoptera, cerambycidae, lamiinae).  

PubMed

The Tribe Hemilophini (Lamiinae) is reviewed for Hispaniola and an identification key is provided. Fifteen species are now known from the island, including one new species of Adesmus (Adesmus fortunei from Pedernales and La Vega Provinces, Dominican Republic), one new species of Oedudes (Oedudes anulatus from Peravia and La Vega Provinces, Dominican Republic), and five new species of Calocosmus (Calocosmus contortus from San Cristóbal Province, Calocosmus punctatus from Peravia Province, Calocosmus rawlinsi from Elías Piña Province, Calocosmus robustus from La Vega Province, and Calocosmus thonalmus from La Altagracia Province, all in the Dominican Republic). Oedudes and Adesmus are new island and country records for Hispaniola and Dominican Republic, respectively. Calocosmus holosericeus Gahan is a new synonym of Calocosmus janus Bates. In addition to the new species, five new country records and four new island records are presented for Calocosmus. PMID:23653499

Lingafelter, Steven W

2013-01-15

58

Deformation partitioning at the junction between the Enriquillo fault and the Trans-Haitian belt  

Microsoft Academic Search

The recent Haiti earthquake, although it ruptured dramatically the strike-slip Enriquillo Plantain Garden Fault Zone (EPGFZ), is actually located where this fault cross-cut or is overlapped by the frontal part of the Trans-Haitian belt accretionary wedge. This belt started accreting flysch series in the North of Hispaniola during the late Palaeogene and propagated onto the carbonate platform during the Miocene

S. Leroy; M. Pubellier; N. Ellouz; R. Momplaisir; D. Boisson; H. Amilcar

2010-01-01

59

Morphology, structure, and tectonic evolution of the Mona canyon (northern Mona passage) from multibeam bathymetry, side-scan sonar, and seismic reflection profiles  

NASA Astrophysics Data System (ADS)

The submarine Mona Canyon is a rift between Puerto Rico and Hispaniola of the Greater Antilles. An integrated marine geophysical data set, including multibeam bathymetry, side-scan sonar imagery, single channel and multichannel seismic reflection profiles is used to evaluate the morphology, structure, and tectonic evolution of the Mona Canyon. A structural restoration of the central Mona canyon indicates that extension in the rift initiated in the Middle Oligocene, approximately 30 Ma. A minimum total extension of 6.1 km and a minimum longitudinal strain of 11.4% across the central Mona canyon are calculated. The overall extension is proposed to have occurred over two phases. Phase I occurred from the Middle Oligocene to Late Miocene, and was a slow (0.09 mm/yr) stage of at least 1.7 km of opening. Phase II was most likely controlled by the impact of the subducted southeast portion of the Bahamas platform beneath the northeastern Caribbean plate margin. Phase II was a more rapid (0.4 mm/yr) stage of extension of at least 4.4 km that occurred from the Late Pliocene to the Recent as the SE Bahamas collision warped the middle and upper slope of the northern Puerto Rico margin along its advancing path and slowed the eastward movement of Hispaniola relative to Puerto Rico. The upper reaches of the Mona canyon form the trailing edge of the Puerto Rico-Virgin Islands block as it pulls away from a pinned Hispaniola. The Mona reentrant marks the trailing edge of a northern Hispaniola forearc sliver that forms due to increased coupling between the subducting North America plate and the overriding plate.

Mondziel, Steven; Grindlay, Nancy; Mann, Paul; Escalona, Alejandro; Abrams, Lewis

2010-04-01

60

Neotectonics of Puerto Rico and the Virgin Islands, northeastern Caribbean, from GPS geodesy  

Microsoft Academic Search

The boundary between the North American and Caribbean plates is characterized primarily by left-lateral motion along predominantly east-west striking faults. Seismicity and marine geophysical survey data are consistent with at least two, and possibly three, microplates in the diffuse boundary zone in the northeastern Caribbean: (1) the Gonave, (2) the Hispaniola, and (3) the Puerto Rico-northern Virgin Islands (PRVI). We

Pamela E. Jansma; Glen S. Mattioli; Alberto Lopez; Charles DeMets; Timothy H. Dixon; Paul Mann; Eric Calais

2000-01-01

61

Relative motion between the Caribbean and North American plates and related boundary zone deformation from a decade of GPS observations  

NASA Astrophysics Data System (ADS)

Global Positioning System (GPS) measurements in 1986, 1994, and 1995 at sites in Dominican Republic, Puerto Rico, Cuba, and Grand Turk define the velocity of the Caribbean plate relative to North America. The data show eastward motion of the Caribbean plate at a rate of 21 ± 1 mm/yr (1 standard error ) in the vicinity of southern Dominican Republic, a factor of 2 higher than the NUVEL-1A plate motion model prediction of 11 ± 3 mm/yr. Independent measurements on San Andres Island, and an Euler vector derived from these data, also suggest a rate that is much higher than the NUVEL-1A model. Available data, combined with simple elastic strain models, give the following slip rate estimates for major left-lateral faults in Hispaniola: (1) the North Hispaniola fault offshore the north coast of Hispaniola, 4 ± 3 mm/yr; (2) the Septentrional fault in northern Dominican Republic, 8 ± 3 mm/yr; and (3) the Enriquillo fault in southern Dominican Republic and Haiti, 8 ± 4 mm yr. The relatively high plate motion rate and fault slip rates suggested by our study, combined with evidence for strain accumulation and historical seismicity, imply that seismic risk in the region may be higher than previous estimates based on low plate rate/low fault slip rate models and the relatively low rate of seismicity over the last century.

Dixon, Timothy H.; Farina, Frederic; Demets, Charles; Jansma, Pamela; Mann, Paul; Calais, Eric

1998-07-01

62

Plant-pollinator interactions and floral convergence in two species of Heliconia from the Caribbean Islands.  

PubMed

Variation in interspecific interactions across geographic space is a potential driver of diversification and local adaptation. This study quantitatively examined variation in floral phenotypes and pollinator service of Heliconia bihai and H. caribaea across three Antillean islands. The prediction was that floral characters would correspond to the major pollinators of these species on each island. Analysis of floral phenotypes revealed convergence among species and populations of Heliconia from the Greater Antilles. All populations of H. caribaea were similar, characterized by long nectar chambers and short corolla tubes. In contrast, H. bihai populations were strongly divergent: on Dominica, H. bihai had flowers with short nectar chambers and long corollas, whereas on Hispaniola, H. bihai flowers resembled those of H. caribaea with longer nectar chambers and shorter corolla tubes. Morphological variation in floral traits corresponded with geographic differences or similarities in the major pollinators on each island. The Hispaniolan mango, Anthracothorax dominicus, is the principal pollinator of both H. bihai and H. caribaea on Hispaniola; thus, the similarity of floral phenotypes between Heliconia species suggests parallel selective regimes imposed by the principal pollinator. Likewise, divergence between H. bihai populations from Dominica and Hispaniola corresponded with differences in the pollinators visiting this species on the two islands. The study highlights the putative importance of pollinator-mediated selection as driving floral convergence and the evolution of locally-adapted plant variants across a geographic mosaic of pollinator species. PMID:21792557

Martén-Rodríguez, Silvana; Kress, W John; Temeles, Ethan J; Meléndez-Ackerman, Elvia

2011-07-27

63

Neotectonics of a subduction/strike-slip transition: the northeastern Dominican Republic  

SciTech Connect

The Septentrional fault system in the northeastern Dominican Republic marks the zone where the North American-Carribean plate boundary is evolving from subduction to strike-slip motion, and where terranes appear to be forming and migrating laterally in a subduction complex/forearc region. On the Island of Hispaniola, slip vectors are oblique to the strike of the Puerto Rico trench, and oblique subduction thrusts the upper plate over normal seafloor. The offshore geology and seismicity of the northern Caribbean suggest that uplift, broad crustal warping, thrusting, and strike-slip faulting (ie. collisional tectonics) should be present in the northern part of the Dominican Republic. The high topography (>1000m), high levels of seismicity, and large earthquakes support the hypothesis of contemporary deformation in Hispaniola. In this region, the subduction regime dies out toward the west, and deformation is transferred to onshore, oblique-slip faults. As this change in tectonic style has occurred in Neogene to Recent times, we are investigating the modern evolution of a plate boundary. We have already documented: (1) the presence of a strike-slip faulting in the northeastern Dominican Republic; (2) an anomalous push-up structure; and (3) a region of numerous splay faults. In conclusion, recent seismicity suggest a wide zone of deformation and variations in interplate motions near Hispaniola. This island lies at the western limit of active underthrusting and at the eastern limit of onshore faulting, i.e., at an important transition from a subduction to strike-slip regime.

Winslow, M.A.; McCann, W.R.

1985-01-01

64

Re-emergence of Cholera in the Americas: Risks, Susceptibility, and Ecology  

PubMed Central

Background: The re-emergence of cholera in Haiti has established a new reservoir for the seventh cholera pandemic which threatens to spread to other countries in the Americas. Materials and Methods: Statistics from this new epidemic are compared to the 1991 Peru epidemic, which demonstrated the speed and complexity with which this disease can spread from country to country. Environmental factors implicated in the spread of Vibrio cholerae such as ocean currents and temperatures, as well as biotic factors from zooplankton to waterfowl pose a risk for many countries in the Americas. Results: The movement of people and goods from Hispaniola are mostly destined for North America, but occur to some degree throughout the Americas. These modes of transmission, and the probability of uncontrolled community spread beyond Hispaniola, however, are completely dependent upon risk factors within these countries such as water quality and availability of sanitation. Although North America has excellent coverage of these deterrents to the spread of infectious gastrointestinal diseases, many countries throughout Latin America and the Caribbean lack these basic services and infrastructures. Conclusions: In order to curb the immediate spread of cholera in Hispaniola, treatment availability should be expanded to all parts of the island and phase II epidemic management initiatives must be developed.

Poirier, Mathieu JP; Izurieta, Ricardo; Malavade, Sharad S; McDonald, Michael D

2012-01-01

65

The Life of Hurricane Irene from Caribbean to Canada  

NASA Video Gallery

An animation of satellite observations from August 21 through August 29 showing the birth of Hurricane Irene in the Caribbean and her track over Puerto Rico, Hispaniola, the Bahamas, the U.S. East Coast and into Canada. At her strongest, Irene grew to a Category 3 hurricane on the Saffir-Simpson scale and made landfalls in North Carolina, New Jersey and New York. The GOES-13 cloud images are overlaid on a true-color MODIS map. Storm data from NOAA's GOES-13 satellite. Courtesy: NASA/NOAA GOES Project

Scott Hanger

2011-08-29

66

[Labor force mobility in an area of periphery: three cases from the Caribbean].  

PubMed

"This article deals tentatively with the issue of [labor] migration within an area of the periphery, the Caribbean. Over approximately the last century migration within this area has coexisted with emigration towards North America and the former 'mother countries' in Europe. The focus is on three specific cases: Aruba in the Dutch Antilles, Suriname (former Dutch Guyana) and the island of Hispaniola ([Dominican Republic] and Haiti). These three cases bear evidence to a number of developments in legal and illegal migration today." (SUMMARY IN ENG AND FRE) PMID:12285253

Sansone, L

1992-03-01

67

Space Station Cameras Capture Views of Hurricane Irene From Orbit  

NASA Video Gallery

Aboard the International Space Station, an Expedition 28 crew member captured views of intensifying Hurricane Irene from an altitude of 225 miles at 3:33 p.m. EDT on Aug. 22, 2011, as the tropical system passed to the north of Hispaniola. The National Hurricane Center is forecasting a track that would take Irene near to or east of the Florida peninsula as a major hurricane on Friday with a possible landfall along the southeastern United States on Saturday. As of 11 a.m. EDT on Monday, Irene was packing winds of 80 miles an hour, but growing stronger, moving west-northwest at 13 miles an hour.

Mark Garcia

2011-08-22

68

Hurricane Irene Over Bahamas  

NASA Video Gallery

Video of Hurricane Irene compiled from a series of Astronaut Photography still images taken from the International Space Station on Aug. 24, 2011 (2:12-2:15PM EST). These frames were taken as the ISS flew past the central Caribbean Sea and over the island of Hispaniola; the visible eye can been seen over the southeastern Bahamas region. At the time these images were acquired, Hurricane Irene was a category 3 storm, with maximum sustained winds of 115mph. (Melissa Dawson, Jacobs/ESCG, NASA-JSC)

Sydney B

2011-08-26

69

The January 12, 2010, Mw 7.0 earthquake in Haiti: context and mechanism from an integrated geodetic study  

NASA Astrophysics Data System (ADS)

On January 12, 2010, a Mw7.0 earthquake struck the Port-au-Prince region of Haiti, killing more than 200,000 people and causing an estimated 8 billion in damages, ˜120% of the country's GDP. Understanding this earthquake and its tectonic context is key to future hazard assessment and robust rebuilding in the region. The earthquake was originally thought to have ruptured the Enriquillo fault of the Southern Peninsula of Haiti, one of two main strike-slip faults accommodating the relative motion between the Caribbean and North American plates. Here we provide slip rates on major active faults from the first comprehensive Global Positioning System (GPS) velocity field for Hispaniola. These rates, together with the ˜250 years elapsed since a major event in southern Hispaniola, imply that the Southern Peninsula fault zone was indeed capable of a Mw7.1, consistent with previous estimates. We show that coseismic deformation from GPS and InSAR data is consistent with rupture on an unmapped north-dipping fault, which is subparallel to -- but different from -- the Enriquillo fault. The earthquake involved a combination of left-lateral strike-slip and reverse fault slip, consistent with the transpressional nature of regional interseismic strain accumulation. We will discuss the implications of these findings for the interpretation of the January 12 earthquake and future seismic hazard in the region.

Calais, E.; Freed, A. M.; Mattioli, G. S.; Amelung, F.; Jonsson, S.; Jansma, P. E.; Dixon, T. H.; Prepetit, C.; Momplaisir, R.

2010-12-01

70

Seismic Images of the Crust across the northern Beata Ridge (NE Caribbean)  

NASA Astrophysics Data System (ADS)

The Beata Ridge is a NE-SW trending structure located in the interior of the Caribbean plate, between the extended Colombian and Venezuelan basins. The northern part of the ridge is ~100 km-wide and emerged (Sierra de Bahoruco in the southern Hispaniola Island) and the southern part is ~3500 km- wide and > 4000 m below sea level. It has been suggested that northern part of the ridge is colliding with the E-W tending island arc. In summary, the Hispaniola island arc is being impacted by collision with the Bahamas Bank in the north and by collision with the Beata Ridge in the south. This collision processes jointly with the main E-W component of left-lateral strike-slip have yielded the basin and range physiography observed in the Hispaniola island. To study the macro-structure of the Beata Ridge has likely the key to understand the controversial origin and evolution of the Caribbean plate. A recent combined onshore-offshore CARIBE NORTE survey has been carried out in the Dominican Republic region to study the subduction and collision processes in this area. The marine geophysical cruise aboard the Spanish R/V Hespérides was carried out in spring of 2009. The cruise collected multibeam bathymetry, gravity, magnetic, high-resolution seismic and three-channel seismic reflection data. In the frame of that experiment, a wide angle seismic profile was carried out across the Beata Ridge along a near NW-SE trending line of 200 km length. A set of 5 OBS were anchored along that transect on both sides of the Beata Ridge and 2 seismic land stations at the Beata and Alto Velo Islands, recorded continuously the airgun shots provided by the R/V Hespérides. Processing of the whole dataset is still ongoing, but available results, improve significantly spatial P-wave velocity variations in the upper and middle crust on both sides of the Beata Ridge. In this work, the more recent results from wide angle seismic data across the Beata Ridge are presented.

Nuñez, Diana; Córdoba, Diego; Pazos, Antonio; Martín-Dávila, José; Carbó, Andrés.; Granja-Bruña, José Luis; Payero, Juan; Octavio Cotilla, Mario

2010-05-01

71

Collisional zones in Puerto Rico  

NASA Astrophysics Data System (ADS)

Collisional events along the North American-Caribbean plate boundary are complex and not completely understood. Structures and metamorphism in rocks exposed in Cuba, Hispaniola, and Puerto Rico suggest that the margin has undergone at least three main contractional events in the Early Cretaceous, Late Cretaceous, and in the Late Eocene. The Eocene event is more evident in the transpressional structures preserved in Eocene rocks and may be related to the oblique collision of the northern margin of the Caribbean Plate with continental crust of the Bahamas in the North American Plate. In Puerto Rico, the Late Eocene collisional event is best exposed in the Northern Puerto Rico Fault Zone (NPRFZ) and the Southern Puerto Rico Fault Zone (SPRFZ). These fault zones show transpression in Eocene rocks that suggest contraction and left-lateral shear. The NPRFZ is the boundary between the Northeast and Southwest blocks. Its main fault is the Cerro Mula Fault, a WNW-ESE striking left-lateral fault. The SPRFZ separates the Central and Southwest blocks and strikes NW-SE in the western part of the island. The origin and extent of the Early Cretaceous and Late Cretaceous events are less clear. Recent structural and stratigraphic studies in the Southwest block of Puerto Rico suggest that deformation of Late Cretaceous folded and faulted sedimentary and volcanic rocks, and thrust emplacement of mantle rocks (serpentinized-peridotite) onto the crust are related to Maastrichtian to Paleocene contraction along the plate boundary. In Puerto Rico, there is no metamorphism associated to this event. This deformation constitutes a Late Cretaceous collisional event that is also recognized in Hispaniola and Cuba. Late Cretaceous-Paleocene serpentinite emplacement is attributed to the collision of the subduction zone with the hypothesized Caribeana submerged platform to the north. In Puerto Rico there is a volcanic hiatus in Early Paleocene that may be related to the proposed collision. Reactivation of these structures occurred during Late Eocene-Early Oligocene. The Early Cretaceous tectonic event in Puerto Rico is deduced from stratigraphic relationships of the serpentinite and Late Cretaceous rocks. Early contraction in Cuba and Hispaniola may be related to increased convergence along a subduction zone. However, the characteristics of the tectonic event are not understood. In spite of the temporal similarities of deformation in the northern Caribbean, there are noted differences in the type of deformation that may be related to variations in shape and orientation of pre-existing zones of weaknesses and geographic locations along the Caribbean-North American plate boundary.

Lao Davila, D. A.

2012-04-01

72

Earthquake source parameters for the 2010 January Haiti main shock and aftershock sequence  

NASA Astrophysics Data System (ADS)

Previous analyses of geological and geodetic data suggest that the obliquely compressive relative motion across the Caribbean-North America plate boundary in Hispaniola is accommodated through strain partitioning between near-vertical transcurrent faults on land and low-angle thrust faults offshore. In the Dominican Republic, earthquake focal-mechanism geometries generally support this interpretation. Little information has been available about patterns of seismic strain release in Haiti, however, due to the small numbers of moderate-to-large earthquakes occurring in western Hispaniola during the modern instrumental era. Here, we analyse the damaging MW = 7.0 earthquake that occurred near Port au Prince on 2010 January 12 and aftershocks occurring in the four months following this event, to obtain centroid-moment-tensor (CMT) solutions for 50 earthquakes with magnitudes as small as MW = 4.0. While the 2010 January main shock exhibited primarily strike-slip motion on a steeply dipping nodal plane (strike=250°, dip=71° and rake=22°), we find that nearly all of the aftershocks show reverse-faulting motion, typically on high-angle (30°-45°) nodal planes. Two small aftershocks (MW 4.5 and 4.6), located very close to the main shock epicentre, show strike-slip faulting with geometries similar to the main shock. One aftershock located off the south coast of Haiti shows low-angle thrust faulting. We also examine earthquakes occurring in this region from 1977-2009 successful analysis of four such events provides evidence for both strike-slip and reverse faulting. The pattern of seismic strain release in southern Haiti thus indicates that partitioning of plate motion between transcurrent and reverse structures extends far west within Hispaniola. While we see limited evidence for low-angle underthrusting offshore, most reverse motion appears to occur on high-angle fault structures adjacent to the Enriquillo fault. Our results highlight the need to incorporate seismogenic slip on compressional structures into hazard assessments for southern Haiti.

Nettles, Meredith; Hjörleifsdóttir, Vala

2010-10-01

73

Eremonidiopsis aggregata, gen. n., sp. n. from Cuba, the third West Indian Dioptinae (Lepidoptera, Notodontidae).  

PubMed

A new genus and species of Dioptinae (Lepidoptera, Noctuoidea, Notodontidae) is described from Cuba, this being the third taxon of the subfamily known from the West Indies. Eremonidiopsis aggregata, gen. n., sp. n., appears to be closely related to Eremonidia mirifica Rawlins & Miller from Hispaniola among members of the tribe Dioptini. Eremonidiopsis aggregata is known from two localities in the middle and western portions of the northeastern Cuban mountain range, Nipe-Sagua-Baracoa. The species inhabits low elevations (300-400 m) covered by lowland rainforest and sclerophyll rainforest. The six known specimens, all males, were part of small swarms flying near the top of an unidentified tree during the day at both collecting sites. These localities are included within protected areas, the "Pico Cristal" National Park in the West and the "Alexander von Humbolt" National Park in the East. PMID:24146561

Aguila, Rayner Núñez

2013-09-20

74

Petroleum in the Caribbean Basin: Further exploration justified?  

SciTech Connect

After more than half a century of exploration for petroleum in that part of the Caribbean Basin covered by this review, the prospects for substantial discoveries remain low. Only Barbados has had modest but sustained production of oil and gas. In Hispaniola minor production from small prospects lasted briefly. Exploration in the northeast Caribbean has not resulted in discoveries. Similar exploration in Puerto Rico and, on a more extensive scale, in Jamaica, has also failed to show positive results. On the Nicaragua Rise (Mosquitia, Tela Basins) drilling has produced shows but no production, a situation also evident in Belize. Nevertheless, examination of these results, in the context of the regional geology of the Caribbean Basin, suggests there are areas where further exploration is justified.

Robinson, E. [Univ. of the West Indies, Kingston (Jamaica)

1996-08-01

75

Eremonidiopsis aggregata, gen. n., sp. n. from Cuba, the third West Indian Dioptinae (Lepidoptera, Notodontidae)  

PubMed Central

Abstract A new genus and species of Dioptinae (Lepidoptera, Noctuoidea, Notodontidae) is described from Cuba, this being the third taxon of the subfamily known from the West Indies. Eremonidiopsis aggregata, gen. n., sp. n., appears to be closely related to Eremonidia mirifica Rawlins & Miller from Hispaniola among members of the tribe Dioptini. Eremonidiopsis aggregata is known from two localities in the middle and western portions of the northeastern Cuban mountain range, Nipe–Sagua–Baracoa. The species inhabits low elevations (300–400 m) covered by lowland rainforest and sclerophyll rainforest. The six known specimens, all males, were part of small swarms flying near the top of an unidentified tree during the day at both collecting sites. These localities are included within protected areas, the “Pico Cristal” National Park in the West and the “Alexander von Humbolt” National Park in the East.

Aguila, Rayner Nunez

2013-01-01

76

Paleoseismicity of the North American-Caribbean plate boundary (Septentrional fault), Dominican Republic  

USGS Publications Warehouse

The Septentrional fault zone, the major North American-Caribbean plate-boundary fault in Hispaniola, is a likely source of large earthquakes in the Dominican Republic. An excavation into a Holocene alluvial fan deposited across the fault in the central Cibao Valley, Dominican Republic, provides evidence that it has been at least 430 yr and probably more than 740 yr since the last ground-rupturing earthquake along this segment of the fault. On the basis of these data and published estimates of the plate-tectonic slip rate, it is proposed that the Septentrional fault is a source of high seismic potential in the densely populated and rapidly developing Cibao Valley in the northern Dominican Republic. -Authors

Prentice, C. S.; Mann, P.; Taylor, F. W.; Burr, G.; Valastro, S.

1993-01-01

77

Haiti and the Dominican Republic - same island - different climate adaptation strategies  

NASA Astrophysics Data System (ADS)

The two Caribbean states, Haiti and the Dominican Republic, have experienced similar natural forces since the 18th century, such as for instance, hurricanes and earthquakes. Despite this fact, Haiti tends to be more vulnerable to natural forces than the Dominican Republic, while environmental management strategies have been very different in both countries throughout the 19th century. Research findings show that neither atmospheric nor seismic hazards, which directly hit the territory of Haiti, have significant impacts on long-term population densities and growth rates. Conversely, uncontrolled and unregulated urbanization in Haiti between 1850 and 2009 has systematically exposed more people to natural forces. Thus, Haiti is willing to take increasing human security risks, because, it finally matters where people settle. Population growth versus storm occurrence/frequency in different departments/provinces on Hispaniola island between 1850 and 2009.

Klose, C. D.; Webersik, C.

2010-12-01

78

Correlation between Anolis lizard dewlap phenotype and environmental variation indicates adaptive divergence of a signal important to sexual selection and species recognition.  

PubMed

Although the importance of signals involved in species recognition and sexual selection to speciation is widely recognized, the processes that underlie signal divergence are still a matter of debate. Several possible processes have been hypothesized, including genetic drift, arbitrary sexual selection, and adaptation to local signaling environments. We use comparative analyses to investigate whether the remarkable geographic variation of dewlap phenotype in a Hispaniolan trunk Anolis lizard (A. distichus) is a result of adaptive signal divergence to heterogeneous environments. We recover a repeated pattern of divergence in A. distichus dewlap color, pattern, and size with environmental variation across Hispaniola. These results are aligned with ecological models of signal divergence and provide strong evidence for dewlap adaptation to local signaling environments. We also find that A. distichus dewlaps vary with the environment in a different manner to other previously studied anoles, thus expanding upon previous predictions on the direction dewlaps will diverge in perceptual color space in response to the environment. PMID:23356628

Ng, Julienne; Landeen, Emily L; Logsdon, Ryane M; Glor, Richard E

2012-10-10

79

New seafloor map of the Puerto Rico trench helps assess earthquake and tsunami hazards  

NASA Astrophysics Data System (ADS)

The Puerto Rico Trench, the deepest part of the Atlantic Ocean, is located where the North American (NOAM) plate is subducting under the Caribbean plate (Figure l). The trench region may pose significant seismic and tsunami hazards to Puerto Rico and the U.S.Virgin Islands, where 4 million U.S. citizens reside. Widespread damage in Puerto Rico and Hispaniola from an earthquake in 1787 was estimated to be the result of a magnitude 8 earthquake north of the islands [McCann et al., 2004]. A tsunami killed 40 people in NW Puerto Rico following a magnitude 7.3 earthquake in 1918 [Mercado and McCann, 1998]. Large landslide escarpments have been mapped on the seafloor north of Puerto Rico [Mercado et al., 2002; Schwab et al., 1991],although their ages are unknown.

Brink, Uri ten; Danforth, William; Polloni, Christopher; Andrews, Brian; Llanes, Pilar; Smith, Shepard; Parker, Eugene; Uozumi, Toshihiko

2004-09-01

80

Twin Tsunamis Triggered by the 12 January 2010 Haiti Earthquake  

NASA Astrophysics Data System (ADS)

On 12 January 2010, a magnitude M w 7.0 earthquake occurred 25 km west-southwest of Haiti's capital Port-au-Prince causing an estimated 316,000 fatalities, thereby exceeding any previous loss of life from a similar size earthquake. In addition, tsunami waves triggered by the earthquake caused at least three fatalities at Petit Paradis due to a complete lack of tsunami awareness. The International Tsunami Survey Team (ITST) was deployed within weeks of the event and covered the greater Bay of Port-au-Prince and more than 100 km of Hispaniola's southern coastline. The collected survey data include more than 21 tsunami heights along with observations of coastal land level change. Maximum tsunami heights of 3 m have been measured for two independently triggered tsunamis.

Fritz, Hermann M.; Hillaire, Jean Vilmond; Molière, Emanuel; Wei, Yong; Mohammed, Fahad

2013-09-01

81

Comparison of sand-layer geometry on flat floors of 10 modern depositional basins  

SciTech Connect

A comparative study of 10 deep turbidite basins indicates that sand-layer thickness, frequency, and continuity can be related to their basin geometries, tectonics, and source areas. This study is based on piston-core data from the flat floors of four oceanic-crust abyssal plains (Sohm, Hatteras, Blake-Bahama, and Silver), two Bahama-Plateau reentrant basins (Columbus basin and Tongue of the Ocean), three subduction zone-island arc basins (Hispaniola-Caicos, Navidad, and St. Croix basins), and one continental-borderland basin (Santa Monica basin). With increasing tectonic activity, sand layers on flat basin floors tend to be thinner and more frequent. Except in elongated narrow basins such as Navidad, source-area size is directly related to proximal sand-layer thickness. Continuity of individual sand layers is a function of drainage-basin size and depositional-basin shape. For example, on the Hatteras Abyssal Plan long-distance continuity (up to 500 km) of individual sand layers is achieved because most of the turbidites are large and are introduced only at the north upstream end. In the small horseshoe-shaped Columbus basin, sand-layer continuity is limited because flows are small and are introduced from three sides. In most basins, sands thin and the percentage of sand layers in the sediment column decreases away from source areas. However, in basins that are small relative to the typical turbidity-current size (e.g., Hispaniola-Caicos basin), the differences between basin-edge and basin-center sand layers are slight. 10 figures, 3 tables.

Pilkey, O.H. (Duke Univ., Durham, NC); Locker, S.D.; Cleary, W.J.

1980-06-01

82

Plate Coupling and Strain Partitioning in the Northeastern Caribbean  

NASA Astrophysics Data System (ADS)

Major strike-slip faults commonly found on the margin of overriding plates in oblique subduction zone settings facilitate the partitioning of strain into trench-parallel and trench-normal tectonics. Their development has been proposed to be controlled by factors such as convergence obliquity, basal tractions, magnitude of slab-pull force, or strength of interplate coupling. In the northeastern Caribbean, the direction of GPS velocities and earthquake slip vectors suggests low coupling along the Puerto Rico and Lesser Antilles trenches, but strong coupling to the west along the Hispaniola margin, while the convergence obliquity remains constant. Coincidentally, large strike-slip faults in the overriding plate only develop in Hispaniola, which is also the locus of the largest historical subduction earthquakes in the Caribbean (M8.0, 1946-53 sequence). We investigate interplate coupling at the Caribbean-North American plate boundary using a model that allows for block rotations and elastic strain accumulation on partially coupled faults. Model parameters (block rotations and coupling on interplate faults) are derived from an inversion of earthquake slip vectors and new GPS data covering Haiti, the Dominican Republic, Puerto Rico and the Virgin Islands, and the Lesser Antilles. We find that intraplate coupling is high in the western half of the domain, coincident with the development of large and fast-slipping strike-slip faults in the upper plate that partition the Carribean/North America plate motion, but low in its eastern half, along the Puerto Rico and Lesser Antilles subductions, that show little to no strain partitioning. This suggests that strain partitioning occur only if interplate coupling is large enough to effectively transfer shear stresses to the overriding plate.

Manaker, D.; Calais, E.; Jansma, P.; Mattioli, G.

2006-12-01

83

Population history of the Hispaniolan hutia Plagiodontia aedium (Rodentia: Capromyidae): testing the model of ancient differentiation on a geotectonically complex Caribbean island.  

PubMed

Hispaniola is a geotectonically complex island consisting of two palaeo-islands that docked c. 10 Ma, with a further geological boundary subdividing the southern palaeo-island into eastern and western regions. All three regions have been isolated by marine barriers during the late Cenozoic and possess biogeographically distinct terrestrial biotas. However, there is currently little evidence to indicate whether Hispaniolan mammals show distributional patterns reflecting this geotectonic history, as the island's endemic land mammal fauna is now almost entirely extinct. We obtained samples of Hispaniolan hutia (Plagiodontia aedium), one of the two surviving Hispaniolan land mammal species, through fieldwork and historical museum collections from seven localities distributed across all three of the island's biogeographic regions. Phylogenetic analysis using mitochondrial DNA (cytochrome b) reveals a pattern of historical allopatric lineage divergence in this species, with the spatial distribution of three distinct hutia lineages biogeographically consistent with the island's geotectonic history. Coalescent modelling, approximate Bayesian computation and approximate Bayes factor analyses support our phylogenetic inferences, indicating near-complete genetic isolation of these biogeographically separate populations and differing estimates of their effective population sizes. Spatial congruence of hutia lineage divergence is not however matched by temporal congruence with divergences in other Hispaniolan taxa or major events in Hispaniola's geotectonic history; divergence between northern and southern hutia lineages dates to c. 0.6 Ma, significantly later than the unification of the palaeo-islands. The three allopatric Plagiodontia populations should all be treated as distinct management units for conservation, with particular attention required for the northern population (low haplotype diversity) and the south-western population (high haplotype diversity but highly threatened). PMID:22404699

Brace, Selina; Barnes, Ian; Powell, Adam; Pearson, Rebecca; Woolaver, Lance G; Thomas, Mark G; Turvey, Samuel T

2012-03-08

84

Interseismic Plate coupling and strain partitioning in the Northeastern Caribbean  

NASA Astrophysics Data System (ADS)

The northeastern Caribbean provides a natural laboratory to investigate strain partitioning, its causes and its consequences on the stress regime and tectonic evolution of a subduction plate boundary. Here, we use GPS and earthquake slip vector data to produce a present-day kinematic model that accounts for secular block rotation and elastic strain accumulation, with variable interplate coupling, on active faults. We confirm that the oblique convergence between Caribbean and North America in Hispaniola is partitioned between plate boundary parallel motion on the Septentrional and Enriquillo faults in the overriding plate and plate-boundary normal motion at the plate interface on the Northern Hispaniola Fault. To the east, the Caribbean/North America plate motion is accommodated by oblique slip on the faults bounding the Puerto Rico block to the north (Puerto Rico subduction) and to the south (Muertos thrust), with no evidence for partitioning. The spatial correlation between interplate coupling, strain partitioning and the subduction of buoyant oceanic asperities suggests that the latter enhance the transfer of interplate shear stresses to the overriding plate, facilitating strike-slip faulting in the overriding plate. The model slip rate deficit, together with the dates of large historical earthquakes, indicates the potential for a large (Mw7.5 or greater) earthquake on the Septentrional fault in the Dominican Republic. Similarly, the Enriquillo fault in Haiti is currently capable of a Mw7.2 earthquake if the entire elastic strain accumulated since the last major earthquake was released in a single event today. The model results show that the Puerto Rico/Lesser Antilles subduction thrust is only partially coupled, meaning that the plate interface is accumulating elastic strain at rates slower than the total plate motion. This does not preclude the existence of isolated locked patches accumulating elastic strain to be released in future earthquakes, but whose location and geometry are not resolvable with the present data distribution. Slip deficit on faults from this study are used in a companion paper to calculate interseismic stress loading and, together with stress changes due to historical earthquakes, derive the recent stress evolution in the NE Caribbean.

Manaker, D. M.; Calais, E.; Freed, A. M.; Ali, S. T.; Przybylski, P.; Mattioli, G.; Jansma, P.; Prépetit, C.; de Chabalier, J. B.

2008-09-01

85

Terrain Classification of Aster gDEM for Seismic Microzonation of Port-Au Haiti, Using - and - Based Analytic Methods  

NASA Astrophysics Data System (ADS)

The aftermath of the M7.0 Haiti earthquake of 12 January 2010 witnessed an impressive scientific response from the international community. In addition to conventional post-earthquake investigations, there was also an unprecedented reliance on remote-sensing technologies for scientific investigation and damage assessment. These technologies include sensors from both aerial and space-borne observational platforms. As part of the Haiti earthquake response and recovery effort, we develop a seismic zonation map of Port-au-Prince based on high-resolution satellite imagery as well as data from traditional seismographic monitoring stations and geotechnical site characterizations. Our imagery consists of a global digital elevation model (gDEM) of Hispaniola derived from data recorded by NASA-JPL's Advanced Spaceborne Thermal Emission and Reflection Radiometer (ASTER) instrument onboard the multi-platform satellite Terra. To develop our model we also consider recorded waveforms from portable seismographic stations (Hough et al., in review) and 36 geotechnical shear-wave velocity surveys (Cox et al., in review). Following a similar approach developed by Yong et al. (2008; Bull. Seism Soc. Am.), we use both pixel- and object- based imaging analytic methods to systematically identify and extract local terrain features that are expected to amplify seismic ground motion. Using histogram-stretching techniques applied to the rDEM values, followed by multi-resolution, segmentations of the imagery into terrain types, we systematically classify the terrains of Hispaniola. By associating available Vs30 (average shear-wave velocity in the upper 30 meter depth) calculated from the MASW (Multi-channel Analysis of Surface Wave) survey method, we develop a first-order site characterization map. Our results indicate that the terrain-based Vs30 estimates are significantly associated with amplitudes recorded at station sites. We also find that the damage distribution inferred from UNOSAT (UNITAR Operational Satellite Applications Program) data matches our estimates. However, the strongest amplifications are observed at two stations on a foothill ridge, where Vs30 values indicate that amplification should be relatively lower. Hough et al. (2010, this session) conclude that the observations can be explained by topographic amplification along a steep, narrow ridge. On the basis of these preliminary results, we conclude that the terrain-based framework, which characterizes topographic amplification as well as sediment-induced amplification, is needed to develop a microzonation map for Port-au-Prince.

Yong, A.; Hough, S. E.; Cox, B. R.; Rathje, E. M.; Bachhuber, J.; Hulslander, D.; Christiansen, L.; Abrams, M.

2010-12-01

86

In the Aftermath of Haiti's Earthquake: A Discussion of Lessons Learned  

NASA Astrophysics Data System (ADS)

The 12 January 2010 earthquake in Haiti brought massive devastation to that country (see Figure 1). In this week's issue of Eos, three noted seismologists respond to questions from Eos senior writer Randy Showstack in a news roundtable format. Paul Mann, senior research scientist with the Institute for Geophysics at the University of Texas at Austin, has just returned from Haiti, where he and a colleague worked on a fault rupture survey; they plan to conduct an offshore fault survey soon. Glen Mattioli, professor of geosciences at the University of Arkansas, Fayetteville, has been part of a team conducting a Global Positioning System (GPS) survey of Haiti to measure ground deformation following the earthquake and to install a number of continuous GPS sites to examine after slip, viscoelastic relaxation, and the time return to interseismic deformation (see Figure 2). Work by Mann, Mattioli, and their colleagues has been supported through a U.S. National Science Foundation Rapid Response Research (RAPID) proposal grant provided to Purdue University, with Eric Calais serving as principal investigator. Carol Prentice, a seismologist with the U.S. Geological Survey's Earthquake Hazards Team, has been conducting paleoseismic research on the active faults in the Caribbean region since 1991, including projects on Hispaniola, Puerto Rico, Trinidad, and Jamaica.

Showstack, Randy

2010-02-01

87

Molecular phylogeny and biogeography of West Indian frogs of the genus Leptodactylus (Anura, Leptodactylidae).  

PubMed

Three endemic species of the aquatic-breeding frog genus Leptodactylus are recognized from the West Indies: Leptodactylus albilabris (Puerto Rico and the Virgin Islands), Leptodactylus dominicensis (Hispaniola), and Leptodactylus fallax (Lesser Antilles). DNA sequences were obtained from several mitochondrial genes to resolve taxonomic questions involving these species and to provide insights into their origin and distribution in the islands. We found low levels of sequence divergence between L. dominicensis and L. albilabris, supporting morphological evidence that the former species is a junior synonym of the latter species. Phylogenetic analysis supported previous species-group allocations, finding that L. albilabris is a member of the fuscus group and L. fallax is a member of the pentadactylus group. Molecular time estimates for the divergence of L. albilabris from its closest relative in South America (24-58 million years ago, Ma) and for L. fallax from its closest relative in South America (23-34Ma) indicate that they colonized the West Indies independently by over-water dispersal in the mid-Cenozoic. The absence of detectable sequence divergence between the two extant populations of L. fallax (Dominica and Montserrat), a species used for human food and now critically endangered, suggests that one or both arose by human introduction from an island or islands where that species originated. The relatively minor genetic differentiation of populations of L. albilabris can be explained by vicariance and dispersal in the Pleistocene and Holocene, although human introduction of some populations cannot be ruled out. PMID:17196836

Hedges, S Blair; Heinicke, Matthew P

2006-11-26

88

Haiti.  

PubMed

The U.S. Department's background notes on Haiti briefly describe her geography, people, history, government, economy and foreign relations. Haiti comprises the western third of the Caribbean island Hispaniola, situated east of Cuba. There are 6 million people, growing at 1.9% annually, of African origin. Infant mortality is 124/1000; life expectancy 54 years. The country is undeveloped: 80% live in rural areas; per capita income is $379; literacy is estimated at 23%; most speak Creole, although Haiti is the only officially French speaking nation in the Western hemisphere. The land is hot and dry, largely becoming deforested and eroded. Haiti became independent in 1804 after a slave rebellion. Since then the government has been a succession of dictatorships, leading to constant political and economic disorder. The current transition government rules by decree. The economy is largely based on small subsistence farms. Coffee, cocoa, mangoes, essential oils and locally assembled manufactured goods are exported. Haiti benefits from foreign aid from several institutions and governments, including an active USAID program that fosters soil conservation, education and business. PMID:12177924

1987-04-01

89

Rethinking Antillothrix: the mandible and its implications.  

PubMed

A mandible of the Hispaniolan primate Antillothrix bernensis, virtually complete and providing the only definitive evidence of the species' lower dentition, has been discovered in a submerged Dominican Republic cave. The new specimen enables a more certain assessment of the species' phylogenetic position than previously possible. It belongs to the same individual as the nearly complete young adult cranium and postrcranial elements found earlier at the same site. Of the extinct Caribbean platyrrhines, the jaw compares well with partial mandibles representing Xenothrix mcgregori, from Jamaica. Among living platyrrhines, it closely resembles Callicebus and Aotus, as documented in a biometric analysis employing three-dimensional geometric morphometrics of Callicebus, Aotus, Pithecia, Chiropotes, Cacajao, Cebus, and Saimiri. The jaw falls within the morphological variability of Callicebus and Aotus in this three-dimensional analysis, is otherwise most similar to Pithecia, and is distinct from cebines. Lower molars resemble the Haitian primate, Insulacebus, a genus known by a full dentition and gnathic fragments with a pattern of derived features also present in Xenothrix. Considering the available craniodental and postcranial evidence, we conclude that Antillothrix is not properly classified as cebid but rather is best grouped with Pitheciidae, an idea long central to discussions of the phylogenetic affinities of the Greater Antillean primates. Since Antillothrix and Insulacebus are more primitive anatomically than the highly modified Xenothrix, it is tempting to surmise that the origins of the latter involved a vicariance or dispersal event via Hispaniola isolating it on Jamaica. PMID:23526607

Rosenberger, Alfred L; Klukkert, Zachary S; Cooke, Siobhán B; Rímoli, Renato

2013-03-22

90

Retreat of carbonate platforms: Response to tectonic processes  

SciTech Connect

A SeaMARC 2 and seismic reflection investigation of the deep-water margins of carbonate banks in the southeast Bahamas has documented the retreat of these isolated platforms since mid-Cretaceous time. This retreat is in sharp contrast to prograding carbonate platforms in the passive northwest Bahamas and provides an initial framework within which to view the response of carbonate platforms to tectonic processes. Processes of retreat include large-scale (50-60 km) step-back to platform margins during the mid-Cretaceous; tectonic subsidence and downfaulting during the late Tertiary; and large-scale collapse of platform margins, which may be an active process. Step-back during the mid-Cretaceous correlates with a global tectonic pulse of ocean-crust formation and relative sea-level rise; downfaulting may be a response to either late Tertiary lithospheric bending during subduction and/or block rotation along the North American-Caribbean plate boundary; and collapse may be related to earthquake shocks generated by active plate-tectonic collision between the southwest Bahamas and Hispaniola.

Mullins, H.T.; Andersen, B.; Gaylord, M.; Petruccione, J.L.; Wellner, R.W. (Syracuse Univ., NY (United States)); Dolan, J. (California Inst. of Tech., Pasadena (United States)); Breen, N. (Stanford Univ., CA (United States)); Melillo, A.J.; Jurgens, A.D. (Chevron U.S.A., New Orleans, LA (United States))

1991-11-01

91

Plate interaction in the NE Caribbean subduction zone from continuous GPS observations  

NASA Astrophysics Data System (ADS)

Kinematic similarities between the Sumatra and Puerto Rico Trenches highlight the potential for a mega-earthquake along the Puerto Rico Trench and the generation of local and trans-Atlantic tsunamis. We used the horizontal components of continuous GPS (cGPS) measurements from 10 sites on NE Caribbean islands to evaluate strain accumulation along the North American (NA) - Caribbean (CA) plate boundary. These sites move westward and slightly northward relative to CA interior at rates ?2.5 mm/y. Provided this motion originates in the subduction interface, the northward motion suggests little or no trench-perpendicular thrust accumulation and may in fact indicate divergence north of Puerto Rico, where abnormal subsidence, bathymetry, and gravity are observed. The Puerto Rico Trench, thus, appears unable to generate mega-earthquakes, but damaging smaller earthquakes cannot be discounted. The westward motion, characterized by decreasing rate with distance from the trench, is probably due to eastward motion of CA plate impeded at the plate boundary by the Bahamas platform. Two additional cGPS sites in Mona Passage and SW Puerto Rico move to the SW similar to Hispaniola and unlike the other 10 sites. That motion relative to the rest of Puerto Rico may have given rise to seismicity and normal faults in Mona Rift, Mona Passage, and SW Puerto Rico.

ten Brink, Uri S.; López-Venegas, Alberto M.

2012-05-01

92

The major epidemic infections: a gift from the Old World to the New?  

PubMed

With the discovery of the New World, the Europeans flocked to America and with them spread infectious diseases. During long sea voyages the agents of these diseases increased their diffusion capacity in a suitable environment. Lack of hygiene, fatigue and privations, a diet without vitamins and many persons kept in confined spaces were the essential features of this environment. Sick persons, whose health conditions worsened during the journey to the New World, carried the germs of infectious diseases. The first disease to appear in the New World was smallpox described in 1518 in Hispaniola. From there the disease moved rapidly to Mexico in 1520, exterminating most of the Aztecs, Guatemala and to the territories of Incas from 1525-26, killing most of them and the King himself. The second disease, influenza, appeared in La Isabela, a few years later, causing a heavy epidemic between 1558 and 1559. Other diseases followed such as yellow fever and malaria. So Europeans and these invisible and mortal agents caused enormous destruction of American populations. In fact historians have estimated that beginning from early 1500, in only 50 years the population of Peru and Mexico fell from 60 to 10 million; in the latter country, in one century, the populations fell from an initial 10 million to only 2 million. PMID:10230264

Sessa, R; Palagiano, C; Scifoni, M G; di Pietro, M; Del Piano, M

1999-03-01

93

Fan-delta uplift and mountain subsidence during the Haiti 2010 earthquake  

NASA Astrophysics Data System (ADS)

The relative motion between the Caribbean and North American plates is accommodated by several active faults around Hispaniola Island. The Enriquillo-Plantain Garden fault in southern Haiti is one of these structures. Strain equivalent to a magnitude 7.2 earthquake is estimated to have accumulated along this fault since its last significant activity. The Haiti earthquake of 12 January 2010 was initially reported to have occurred along this fault, but more recent studies proposed slips on previously unrecognized, neighbouring faults. Here we use interferometric synthetic aperture radar data to show that surface deformation caused by the earthquake does not correspond to the present topography. Alluvial fan deltas were uplifted on the north side of the Enriquillo-Plantain Garden fault, whereas mountains located on the south side of the fault subsided, implying that faults other than the Enriquillo-Plantain Garden fault were responsible for the deformation. To determine fault structure, we fit the satellite surface deformation data to a fault model. We show that slip occurred on a fault dipping northward at 42°, with large thrust components. The maximum displacement on the fault was about 4m at 10-20km depth, offshore from the Tiburon peninsula. We confirm that the earthquake ruptured a blind thrust fault and show that the fault could not be identified from large-scale present-day topography.

Hashimoto, Manabu; Fukushima, Yo; Fukahata, Yukitoshi

2011-04-01

94

Flood mapping of the trans-boundary river Soliette (Haiti and the Dominican Republic)  

NASA Astrophysics Data System (ADS)

Over the last decades, Isla Hispaniola (i.e. the territory shared by Haiti and the Dominican Republic) has been sadly affected by several hydro-geological disasters. In fact, the island has been involuntary protagonist of the international chronicles for being hit by the passage of several devastating hurricanes. Incalculable damages to structures and environment and thousand fatalities are the results of such events. A recent and glaring example is that of May 2004, when extreme and intense precipitations, originated by a tropical depression in the Caribbean Sea, occurred over the island, producing a devastating flash-flooding of the river Soliette trans-boundary catchment. The flooding destroyed most of the cities of Jimaní and Fond Verrettes and killed over 1,000 Haitian and Dominican people. The same event also killed 414 people in the Dominican Republic. This presentation shows the analysis of the hydrological and hydraulic behaviour of the river Soliette aimed at modelling the flood event of May 2004 and formulating a trans-boundary flood mitigation plan.

Brandimarte, L.

2009-04-01

95

Testing ecological explanations for biogeographic boundaries.  

PubMed

Barriers to dispersal and resulting biogeographic boundaries are responsible for much of life's diversity. Distinguishing the contribution of ecological, historical, and stochastic processes to the origin and maintenance of biogeographic boundaries, however, is a longstanding challenge. Taking advantage of newly available data and methods--including environmental niche models and associated comparative metrics--we develop a framework to test two possible ecological explanations for biogeographic boundaries: (1) sharp environmental gradients and (2) ribbons of unsuitable habitat dividing two highly suitable regions. We test each of these hypotheses against the null expectation that environmental variation across a given boundary is no greater than expected by chance. We apply this framework to a pair of Hispaniolan Anolis lizards (A. chlorocyanus and A. coelestinus) distributed on the either side of this island's most important biogeographic boundary. Integrating our results with historical biogeographic analysis, we find that a ribbon of particularly unsuitable habitat is acting to maintain a boundary between species that initially diverged on distinct paleo-islands, which merged to form present-day Hispaniola in the Miocene. PMID:21054358

Glor, Richard E; Warren, Dan

2010-11-25

96

Motion of Caribbean Plate during last 7 million years and implications for earlier Cenozoic movements  

NASA Astrophysics Data System (ADS)

The direction and rate of movement of the Caribbean plate with respect to North America are determined from the slip vectors of shallow earthquakes and from the configuration of downgoing seismic zones in the Greater and Lesser Antilles. A calibration of the relative plate motion for the northeastern Caribbean using data from other subduction zones indicates an average rate of 3.7±0.5 cm/yr for the past 7 million years (Ma). The direction of plate motion inferred from focal mechanisms (ENE) is nearly the same as that deduced from the configuration of downgoing seismic zones going around the major bend in the arc. With respect to North America, the Caribbean plate is moving at an angular velocity of 0.36°/Ma about a center of rotation near 66°N, 132°W. Vector addition using those data and that for the relative motion of North and South America indicates that the Caribbean is moving at an angular velocity of 0.47°/Ma about a center of rotation near 60°N, 88°W with respect to South America. The presence of intermediate-depth earthquakes beneath Puerto Rico and the Virgin Islands is ascribed to the curvature of the plate boundary and a component of underthrusting that has been going on for at least the past 7 Ma and is likely occurring today. The alternative hypothesis that earthquakes beneath those areas are occurring in materials that were subducted during the Eocene, the last major episode of magmatism, is not tenable from thermal considerations. The lack of recent magmatism in the eastern Greater Antilles is ascribed to the relatively small component of underthrusting. The 2 cm/yr rate of seafloor creation along the mid-Cayman spreading center for the past 2.4 Ma does not appear to reflect the total Caribbean-North American plate motion while the 4 cm/yr spreading rate from 6.0 to 2.4 Ma does. Between the mid-Cayman spreading center and eastern Guatemala, the northern boundary of the Caribbean plate is narrow and follows the southern margin of the Cayman trough. Seismic activity between the spreading center and eastern Hispaniola, however, occurs over a zone about 250 km wide that extends from Cuba to Jamaica and across the entire width of Hispaniola. Individual faults within this broad plate boundary appear to have accommodated differing amounts of motion as a function of geological time while the cumulative plate motion across the zone remained nearly constant. The percentage of total plate motion accommodated near southern Hispaniola and Jamaica is inferred to have increased about 2.4 Ma ago. That change may have been caused by the collision of parts of the Bahama bank and northern Hispaniola. This explanation for the sudden decrease in seafloor creation along the mid-Cayman spreading center is less catastrophist than the hypothesis that the entire Caribbean plate suddenly changed its velocity with respect to surrounding plates. The Caribbean plate may be regarded as a small buffer plate whose motion is now governed by the movement of the larger North and South American plates which bound it on three sides. The Caribbean plate is either at rest or moving eastward at a rate of no more than 1 cm/yr in the hot spot reference frame. Since the relative motion of the larger plates surrounding the Caribbean has been nearly constant for the last 38 Ma (anomaly 13 time) and since the forces on the Caribbean plate do not appear to have changed greatly during that interval, we extrapolate the motion of the last 7 Ma back to 38 Ma. A reconstruction for the late Eocene places the Caribbean plate about 1400 km west of its present position. The faster rate of plate motion we calculate makes it more likely that the lithosphere beneath the basins of the Caribbean originated in the Pacific. It also has implications for the seismic potential of the region, paleocirculation in the Atlantic Ocean and origin of sediments in the area. Our late Eocene reconstruction aligns the eastern continental margin of Yucatan with that along the southeast side of the Nicaragua rise. This 2500-km-long feature may have acted as an arc-arc transform

Sykes, Lynn R.; McCann, William R.; Kafka, Alan L.

1982-12-01

97

Conservation and management of the American crocodile  

NASA Astrophysics Data System (ADS)

The American crocodile is a rare and endangered species, the range of which has contracted to disjunct locations such as Hispaniola, Jamaica, Cuba, Panama, and southern Florida. In an attempt to determine what factors might be limiting population growth, an extensive collaborative research program was conducted in 1978 82 in southern Florida. Limiting factors explicitly studied included climate, hurricanes, population dispersion, nesting habitat, fertility, predation, nest chamber environment, juvenile survivorship, artificial mortality, disturbance, and environmental contamination. No single natural factor limits the population, although in concert various factors result in low adult recruitment rates. Such natural limitations explain the natural rarity of this tropical species at the temperate limits of its range. Two artificial sources of mortality are death of adults on roads and the flooding of nests by high groundwater tables. These sources of mortality are potentially controllable by the appropriate management agencies. Active management, by such means as protection of individuals, habitat preservation and enhancement, nest site protection, and captive breeding, is also appropriate for assuring the survival of a rare species. The American crocodile has survived in southern Florida in face of extensive human occupancy of parts of its former nesting habitat, demonstrating the resilience of a threatened species. This case history illustrates the efficacy of conducting research aimed at testing specific management hypotheses, the importance of considering biographical constraints limiting population status in peripheral populations, the need for active management of rare species, and the role of multiple reserves in a conservation and management strategy.

Kushlan, James A.

1988-11-01

98

Fractal clustering pattern of Earthquakes in Haiti Region  

NASA Astrophysics Data System (ADS)

12 January 2010 earthquake was a catastrophic magnitude (Mw =7.0) earthquake with an epicenter near the town of Leogane(18.44N, 72.57W), with the depth of earthquake was 13Km on the blind thrust faults associated with the Enriquillo-Plantain Garden fault system. Modern tectonic activity is forced by the convergent movements between the plates: The Caribbean tectonic plate shifts eastward in relation to North American plate. Highly complex geodynamic process of this region makes it well suited for fractal seismic analysis. Data between March 2000 to December 2009, prior to main shock, was studied for the entire Caribbean-North America plate boundary in the region of Hispaniola using spatial fractal correlation dimension (Dc) approach for the detection of clustering pattern in the narrow time span prior to the main strong events. Based on the spatio-temporal clustering pattern indicated by relatively low Dc (very close to the value of 1) of the past intermediate size events prior to strong event, the potential for future large events can also be assessed. Spatio-temporal clustering pattern of events apparently indicates a highly stressed region, an asperity or weak zone from where the rupture propagation may have eventually nucleated, causing strong earthquake may be used as clue for going detail hazard study.

Singha Roy, P. N.; Agrawal, M.

2011-12-01

99

Plate interaction in the NE Caribbean subduction zone from continuous GPS observations  

USGS Publications Warehouse

Kinematic similarities between the Sumatra and Puerto Rico Trenches highlight the potential for a mega-earthquake along the Puerto Rico Trench and the generation of local and trans-Atlantic tsunamis. We used the horizontal components of continuous GPS (cGPS) measurements from 10 sites on NE Caribbean islands to evaluate strain accumulation along the North American (NA) - Caribbean (CA) plate boundary. These sites move westward and slightly northward relative to CA interior at rates ?2.5 mm/y. Provided this motion originates in the subduction interface, the northward motion suggests little or no trench-perpendicular thrust accumulation and may in fact indicate divergence north of Puerto Rico, where abnormal subsidence, bathymetry, and gravity are observed. The Puerto Rico Trench, thus, appears unable to generate mega-earthquakes, but damaging smaller earthquakes cannot be discounted. The westward motion, characterized by decreasing rate with distance from the trench, is probably due to eastward motion of CA plate impeded at the plate boundary by the Bahamas platform. Two additional cGPS sites in Mona Passage and SW Puerto Rico move to the SW similar to Hispaniola and unlike the other 10 sites. That motion relative to the rest of Puerto Rico may have given rise to seismicity and normal faults in Mona Rift, Mona Passage, and SW Puerto Rico.

ten Brink, Uri S.; Lopez-Vegas, Alberto M.

2012-01-01

100

First skull of Antillothrix bernensis, an extinct relict monkey from the Dominican Republic  

PubMed Central

The nearly pristine remains of Antillothrix bernensis, a capuchin-sized (Cebus) extinct platyrrhine from the Dominican Republic, have been found submerged in an underwater cave. This represents the first specimen of an extinct Caribbean primate with diagnostic craniodental and skeletal parts in association, only the second example of a skull from the region, and one of the most complete specimens of a fossil platyrrhine cranium yet discovered. Cranially, it closely resembles living cebines but is more conservative. Dentally, it is less bunodont and more primitive than Cebus, with crowns resembling Saimiri (squirrel monkeys) and one of the oldest definitive cebines, the late Early Miocene Killikaike blakei from Argentina. The tricuspid second molar also resembles the enigmatic marmosets and tamarins, whose origins continue to present a major gap in knowledge of primate evolution. While the femur is oddly short and stout, the ulna, though more robust, compares well with Cebus. As a member of the cebid clade, Antillothrix demonstrates that insular Caribbean monkeys are not monophyletically related and may not be the product of a single colonizing event. Antillothrix bernensis is an intriguing mosaic whose primitive characters are consistent with an early origin, possibly antedating the assembly of the modern primate fauna in greater Amazonia during the La Venta horizon. While most Greater Antillean primate specimens are quite young geologically, this vanished radiation, known from Cuba (Paralouatta) and Jamaica (Xenothrix) as well as Hispaniola, appears to be composed of long-lived lineages like several other mainland clades.

Rosenberger, Alfred L.; Cooke, Siobhan B.; Rimoli, Renato; Ni, Xijun; Cardoso, Luis

2011-01-01

101

First skull of Antillothrix bernensis, an extinct relict monkey from the Dominican Republic.  

PubMed

The nearly pristine remains of Antillothrix bernensis, a capuchin-sized (Cebus) extinct platyrrhine from the Dominican Republic, have been found submerged in an underwater cave. This represents the first specimen of an extinct Caribbean primate with diagnostic craniodental and skeletal parts in association, only the second example of a skull from the region, and one of the most complete specimens of a fossil platyrrhine cranium yet discovered. Cranially, it closely resembles living cebines but is more conservative. Dentally, it is less bunodont and more primitive than Cebus, with crowns resembling Saimiri (squirrel monkeys) and one of the oldest definitive cebines, the late Early Miocene Killikaike blakei from Argentina. The tricuspid second molar also resembles the enigmatic marmosets and tamarins, whose origins continue to present a major gap in knowledge of primate evolution. While the femur is oddly short and stout, the ulna, though more robust, compares well with Cebus. As a member of the cebid clade, Antillothrix demonstrates that insular Caribbean monkeys are not monophyletically related and may not be the product of a single colonizing event. Antillothrix bernensis is an intriguing mosaic whose primitive characters are consistent with an early origin, possibly antedating the assembly of the modern primate fauna in greater Amazonia during the La Venta horizon. While most Greater Antillean primate specimens are quite young geologically, this vanished radiation, known from Cuba (Paralouatta) and Jamaica (Xenothrix) as well as Hispaniola, appears to be composed of long-lived lineages like several other mainland clades. PMID:20659936

Rosenberger, Alfred L; Cooke, Siobhán B; Rímoli, Renato; Ni, Xijun; Cardoso, Luis

2010-07-21

102

Global survey of frequency dependent attenuation  

NASA Astrophysics Data System (ADS)

We analyze frequency-dependent attenuation of Lg waves, 1/Q(f), for numerous tectonic environments. Tectonic environments studied include: south Pacific oceanic subduction zone near Samoa, the oblique subduction zone off Hispaniola, two continental-oceanic subduction zones in Chile and Alaska, the continental-continental collision zone of the Tibetan Plateau, stable continental interior regions of the central US and Colorado Plateau, the eastern US passive margin and the active margins of the western US. Lg propagates with a group velocity of about 3.5 km/s, the average crustal shear wave velocity. This wave is commonly observed as the dominant phase on high-frequency seismograms at regional distances and is generated by a superposition of higher-mode surface waves or multiply-reflected shear energy in a crustal waveguide. Consequently, Lg provides a good measure of path-averaged crustal properties, such as shear-wave velocity and attenuation. Lg is particularly useful since its amplitude is sensitive to lateral heterogeneity in the crust due to varying tectonic environment. In this global survey we observe that Lg attenuation is generally higher for tectonically active regions than for stable continental interiors. Q(f) is an important physical parameter and is required for a variety of USGS research projects such as the simulation of strong ground motion and seismic network magnitude detection threshold modeling.

McNamara, D. E.; Benz, H.; Gee, L. S.; Frankel, A. D.

2011-12-01

103

Migration of Neogene marine environments, southwestern Dominican Republic  

SciTech Connect

The Azua Basin contains a 4000-m-thick regressive Neogene sedimentary sequence that records the effects of neotectonic activity along the northern bounary of the Caribbean plate. Shifts of benthic foraminiferal depth zone boundaries between stratigraphic sections demonstrate a southeastward migration of paleoenvironments in the Miocene and early Pliocene which suggest that the Hispaniola restraining bend was activated near the beginning of the late Miocene. In the morthwestern part of the Azua basin, the boundary between the middle and upper bathyal biofacies is in the uppermost Miocene Globorotalia humerosa Zone; the bathyal-neritic boundary is near the top of the same zone. In contrast, toward the southeastern (i.e., seaward) end of the basin, the middle bathyal/upper bathyal boundary is just above the base of the lower Pliocene Globorotalia margaritae margaritae Subzone, and the bathyal-neritic transition falls within the upper part of the same zone or in the overlying Globorotalia margaritae evoluta Subzone. The diachroneity of biofacies boundaries spans a time interval of ca. 1 m.y. The foraminiferal trends are corroborated by the disposition of time-transgressive lithofacies.

McLaughlin, P.P. Jr. (Exxon Production Research Co., Houston, Texas (USA)); Sen Gupta, B.K. (Louisiana State Univ., Baton Rouge (USA))

1991-03-01

104

Distributed Active Folding across the Northern Caribbean Plate Boundary Derived from the Combined Analysis of Srtm Topography and Seismic Profiling  

NASA Astrophysics Data System (ADS)

Sinistral transpression across the northern Caribbean plate boundary is partitioned across Hispaniola between two subparallel transforms that accommodate strike-slip motion, and a wide swath of intervening NW-trending folds. These folds correspond to mountain chains continuous with offshore anticlinal ridges. The mapping of onshore flights of marine terraces exposed across these folds, combined with the dating of fossil corals, have constrained uplift rates for their emerged portions [Mann et al., 1995]. Slope maps produced from recently released SRTM (Shuttle Radar Topography Mission) data with a resolution of ~30 m highlight the full 3D geometry of the deformed marine terraces across these folds. Offshore multichannel seismic reflection (MCS) profiles collected in 1982 by GSI / Western Geophysical constrain the broader geometry of the submerged anticline limbs. This combined dataset is used to investigate the deformation history of four folds whose emerged limbs are only moderately disrupted by mass wasting. One of the exposed structures (St Marc peninsula) displays both fold limbs, with the highest uplift predictably centered on the axial trace of the fold. Two others display terraces that remain planar and are progressively tilted away from the presumed anticline crests, indicating in each case that only one of the fold limbs is exposed above sea level and that it is subsiding relative to the crest. Lastly, the west end of Gonave Island, the WNW-trending island located between the north and south peninsulas of Haiti, displays nearly horizontal terraces. While prior investigation of the lowest ~125 ka terrace indicates that it has not uplifted since it was formed [Mann et al., 1995], nearshore MCS data reveal a ~350 m-deep horizontal erosional surface that truncates folded reflectors. This suggests that the submerged portion of the Gonave anticline crest is subsiding. Furthermore, progressive tilting of the seismic reflectors on the fold limbs requires that these limbs are subsiding relative to the crest. Major extension, inferred to be Eocene, is seismically imaged north of Gonave Island, with the post-extension angular unconformity now lying at up to several km depth. The extended, thinned crust is expected to have subsided, a process augmented by post-extension sedimentation. Therefore, a lack of subsidence for the ~125 ka terrace on Gonave Island likely requires some growth of structural relief. We propose that such structural growth is driven by slip on an imaged blind NNE-dipping thrust fault beneath Gonave Island. These results will be used to evaluate whether significant amount of contraction has been recently accommodated across the thrust folds, and what process may be causing subsidence despite folding and, presumable, crustal thickening. The distribution and partitioning of strain on and near western Hispaniola are critical information for evaluating the seismic hazards facing Haiti.

Cormier, M.; Seeber, L.; Sorlien, C. C.; Steckler, M. S.; Gulick, S. P.; McHugh, C. M.; Hornbach, M.

2011-12-01

105

Studies on mosquito borne dieases in Egypt and Qatar.  

PubMed

Mosquitoes identification, distribution and densities in representative Egyptian Governorates and five Qatarain Municipalities (Al Rayyan, Doha, Al Daayan, Al Khor & Al Zahakira and Al Shamal) were studied. In Qatar the larvae were Culex pipiens complex, C. univettatus, C. pusillus, Aedes caspies, Anopheles multicolor and A. stephensi. C. pipiens and C. univettatus were mainly in Al Rayyan, Doha, and Al Khor & Al Zahakira. C. pusillus was in Doha and Al Daayan while A. caspies was in Al Daayan and Al Shamal. Anopheles multicolor and A. stephensi were mainly in Al Shamal with low density in Al Rayyan (only in Ain-Khalid locution). The Egyptian mosquitoes were C. pipiens, C. antennatus, C. thelerei, C. univittatus, C. perexiguus, C. poicilipes, C. pusillus, Aedes caspius, Ae. detritus, A. sergentii, A. pharoensis, A. multicolor, A. detali, A. algeriensis, A. tenebrosus, A. gambiae (formerly), A. superpictus, A. tarkhadi, A. hispaniola, A. rhodesiensis, A. stephensi, A. coustani and Culiseta longiareolata. As an example in Sharkia Governorate, larvae were C. pipiens (68.77%), Ae. caspius (15.75%), Culiseta sp. (=Theobaldia) and C. pusillus. In Greater Cairo, parts of Qualyoubia G., C. pipiens was the most dominant and the least was C. perexiguus. In parts of Giza G., C. pipiens was the most dominant and least was Cs. longiareolata. In Cairo G., C. pipiens was the most dominant and least was Ae. caspius. The overall in Greater Cairo was C. pipiens (61.74%), Cs. longiareolata (15.56%), Ae. caspius (15.3%), C. pusillus (4.0%) and C. perexiguus (3.16%). PMID:20120742

Mikhail, Micheal W; Al-Bursheed, Khalifa M; Abd El-Halim, Azza S; Morsy, Tosson A

2009-12-01

106

Circulating vaccine-derived polioviruses: current state of knowledge.  

PubMed Central

Within the past 4 years, poliomyelitis outbreaks associated with circulating vaccine-derived polioviruses (cVDPVs) have occurred in Hispaniola (2000-01), the Philippines (2001), and Madagascar (2001-02). Retrospective studies have also detected the circulation of endemic cVDPV in Egypt (1988-93) and the likely localized spread of oral poliovirus vaccine (OPV)-derived virus in Belarus (1965-66). Gaps in OPV coverage and the previous eradication of the corresponding serotype of indigenous wild poliovirus were the critical risk factors for all cVDPV outbreaks. The cVDPV outbreaks were stopped by mass immunization campaigns using OPV. To increase sensitivity for detecting vaccine-derived polioviruses (VDPVs), in 2001 the Global Polio Laboratory Network implemented additional testing requirements for all poliovirus isolates under investigation. This approach quickly led to the recognition of the Philippines and Madagascar cVDPV outbreaks, but of no other current outbreaks. The potential risk of cVDPV emergence has increased dramatically in recent years as wild poliovirus circulation has ceased in most of the world. The risk appears highest for the type 2 OPV strain because of its greater tendency to spread to contacts. The emergence of cVDPVs underscores the critical importance of eliminating the last pockets of wild poliovirus circulation, maintaining universally high levels of polio vaccine coverage, stopping OPV use as soon as it is safely possible to do so, and continuing sensitive poliovirus surveillance into the foreseeable future. Particular attention must be given to areas where the risks for wild poliovirus circulation have been highest, and where the highest rates of polio vaccine coverage must be maintained to suppress cVDPV emergence.

Kew, Olen M.; Wright, Peter F.; Agol, Vadim I.; Delpeyroux, Francis; Shimizu, Hiroyuki; Nathanson, Neal; Pallansch, Mark A.

2004-01-01

107

Late Holocene liquefaction features in the Dominican Republic: A powerful tool for earthquake hazard assessment in the northeastern Caribbean  

USGS Publications Warehouse

Several generations of sand blows and sand dikes, indicative of significant and recurrent liquefaction, are preserved in the late Holocene alluvial deposits of the Cibao Valley in northern Dominican Republic. The Cibao Valley is structurally controlled by the Septentrional fault, an onshore section of the North American-Caribbean strike-slip plate boundary. The Septentrional fault was previously studied in the central part of the valley, where it sinistrally offsets Holocene terrace risers and soil horizons. In the eastern and western parts of the valley, the Septentrional fault is buried by Holocene alluvial deposits, making direct study of the structure difficult. Liquefaction features that formed in these Holocene deposits as a result of strong ground shaking provide a record of earthquakes in these areas. Liquefaction features in the eastern Cibao Valley indicate that at least one historic earthquake, probably the moment magnitude, M 8, 4 August 1946 event, and two to four prehistoric earthquakes of M 7 to 8 struck this area during the past 1100 yr. The prehistoric earthquakes appear to cluster in time and could have resulted from rupture of the central and eastern sections of the Septentrional fault circa A.D. 1200. Liquefaction features in the western Cibao Valley indicate that one historic earthquake, probably the M 8, 7 May 1842 event, and two prehistoric earthquakes of M 7-8 struck this area during the past 1600 yr. Our findings suggest that rupture of the Septentrional fault circa A.D. 1200 may have extended beyond the central Cibao Valley and generated an earthquake of M 8. Additional information regarding the age and size distribution of liquefaction features is needed to reconstruct the prehistoric earthquake history of Hispaniola and to define the long-term behavior and earthquake potential of faults associated with the North American-Caribbean plate boundary.

Tuttle, M. P.; Prentice, C. S.; Dyer-Williams, K.; Pena, L. R.; Burr, G.

2003-01-01

108

Are subspecies of Anolis lizards that differ in dewlap color and pattern also genetically distinct? A mitochondrial analysis.  

PubMed

Subspecies of Anolis lizards are often defined on the basis of geographic variation in the color and pattern of the dewlap, an extensible throat fan considered central to species recognition and sexual selection. Among the most impressive examples of this phenomenon are two species of trunk anoles found across Hispaniola and the Bahamas: Anolis distichus is divided into 16 subspecies with dewlap colors ranging from deep wine red to pale yellow while Anolis brevirostris is divided into three subspecies with dewlaps ranging from pale yellow to orange. Limited sampling of allozyme data indicates some genetic divergence among subspecies and suggests that they may deserve recognition at the species-level. Our goal here is to use more comprehensive geographic sampling of mtDNA haplotypes to test whether the five subspecies of A. distichus and three subspecies of A. brevirostris that occur in the Dominican Republic correspond with genetically distinct populations that may warrant recognition under the general lineage concept. We obtain an aligned dataset of 1462bp comprised of the genes encoding ND2 and adjacent tRNAs from 76 individuals of A. distichus from 28 localities and 12 individuals of A. brevirostris from five localities. We find that haplotypes sampled from each Dominican subspecies of A. distichus form well-supported and deeply divergent clades (>10% uncorrected sequence divergence). Strong concordance between mtDNA haplotype structure and previously diagnosed phenotypic variation in traits central to interspecific communication (i.e., the dewlap) leads us to hypothesize that each of the presently recognized Dominican subspecies of A. distichus and A. brevirostris deserves elevation to full species status under the general lineage concept. PMID:21075209

Glor, Richard E; Laport, Robert G

2010-11-12

109

Puerto Rico trench: site of a shallow-water Tertiary basin and regional tectonic implications  

SciTech Connect

Until late Eocene time, the Bahamas platform extended to the present Virgin Islands, as demonstrated by magnetic, gravity, and refraction data. This interpretation is confirmed by the presence of widespread outcrops of middle Cretaceous through early Pliocene shallow-water bank carbonates below 5200 m depth in the trench. Crustal thickness beneath this bank is 18-25 km. Igneous and metamorphic rocks from the base of the trench's southern slope are chemically very different from subduction-zone rocks. Waters of the carbonate bank (300 x 100 km in size) transgressed southward after early Eocene time. During late Eocene time, the bank's southern margin was near today's shoreline where down-to-the-north growth faults formed. Along the bank's northern margin, block faulting produced a graben above the site of the modern Puerto Rico Trench. During middle Eocene to early Pliocene time, shallow-water deposition extended from a position presently 5200 m deep in the trench to central Puerto Rico, an exceptionally stable block at least 100 km wide. During middle Eocene time, the Beata Ridge dextral shear cut the trench off north of Hispaniola. In early Pliocene time, the Mona Canyon dextral fault zone cut across the trench, and strong northward tilting commenced. The trench's present southern slope is mainly a dip slope, inclined about 5/sup 0/. The Puerto Rico Outer Ridge formed by lateral and upward movements of mantle materials that withdrew from beneath the sinking trench. Petroleum prospects presently are limited to the Tertiary (4000 m thick) and to a coastal zone 20-25 km wide (to 2000 m water depth). Traps are mainly fault seals and stratigraphic pinch-outs.

Krieg, E.A.; Meyerhoff, A.A.; Taner, I.

1985-02-01

110

Jurassic hydrocarbon exploration of southern Florida  

SciTech Connect

South Florida Jurassic exploration has been overlooked as a viable exploration target due to lack of data and plate-tectonics application. In Florida, {open_quotes}basement{close_quotes} is defined as crystalline, igneous, metamorphic, and unmetamorphosed sediments of Paleozoic age. Age-dating of zircons has proven that the Florida lower Paleozoic terrane is not akin to that of North America but is part of the West African Guinean shield. Previous published reconstructions of late Paleozoic fits of crustal plates and continents have failed to account for the differences in peninsula Florida basement and the geologic and tectonic continuities of peninsula Florida, Yucatan, Cuba, Hispaniola, and Bahamas. Pre-Atlantic reconstruction of the Gulf of Mexico in this study proposes that there was a Florida connection to Yucatan-Cuba-Africa during the Triassic. This reconstruction also shows that the Jurassic sediments that are well known in the northern Gulf Coast should have been deposited in similar depositional environments in southern Florida. Deep drilling on the Florida peninsula has confirmed this hypothesis. By using plate tectonic reconstruction based on the rising of the North Atlantic Ocean and evidence from petrology of basement samples from deep wells together with petrographic analyses of Jurassic sediments, a Smackover-equivalent exploration play can be developed. Petrographic and petrophysical analysis of these wells that have encountered Jurassic marine shales, anhydrite, dolomite, carbonate, and elastic sediments has determined that these sediments are from shallow-water subtidal, tidal, intertidal, and supratidal environments. Excellent gas shows, oil stain in the pores and high TOC values in the marine shales, indicate that large accumulations of hydrocarbon are present.

Mitchell-Tapping, H.J. [Retog, Inc., DeSoto, TX (United States)

1994-09-01

111

The October 11, 1918 Mona Passage tsunami modeled using new submarine landslide evidence.  

NASA Astrophysics Data System (ADS)

The October 11, 1918 ML 7.5 earthquake in the Mona Passage betweeen Hispaniola and Puerto Rico generated a local tsunami that claimed approximately 100 lives along the western coast of Puerto Rico. The area affected by this tsunami is now many-fold more populated. Although the exact cause of the tsunami is still unclear, newly-acquired high-resolution bathymetry of the Mona Passage and seismic reflection lines show a fresh submarine landslide 12 km northwest of Rincón in northwestern Puerto Rico and in the vicinity of the earthquake epicenter determined by Doser et al., (2005). The landslide area is approximately 76 km2 and probably displaced a total volume of 10 km3. The landslide's head scarp is at a water depth of 1.2 km, with the debris flow extending down to a water depth of 4.5 km. The seismic profiles and multibeam bathymetry indicate that the previously suggested source of the 1918 tsunami, a normal fault along the east side of Mona Rift (Mercado and McCann, 1998), was not active recently. The fault escarpment along Desecheo Ridge, which is near the Doser et al., (2005) epicenter, and our landslide appear, on the other hand, to be rather fresh. Using the extended, weakly non-linear hydrodynamic equations implemented in the program COULWAVE (Lynett and Liu, 2002), we modeled the tsunami by a landslide with a finite duration and with the observed dimensions and location. Marigrams (time series of sea level) were calculated at locations near to reported locations of runup. The marigrams show a leading depression wave followed by a maximum positive amplitude in good agreement with the reported polarity, relative amplitudes, and arrival times. Our results suggest this newly-identified landslide, which was likely triggered by the 1918 earthquake, was the probable cause of the October 11, 1918 tsunami and not a normal fault rupture as previously suggested.

López, A. M.; ten Brink, U.; Geist, E.

2007-12-01

112

New Seafloor Map of the Puerto Rico Trench Helps Assess Earthquake and Tsunami Hazards  

NASA Astrophysics Data System (ADS)

The Puerto Rico Trench, the deepest part of the Atlantic Ocean, is located where the North American (NOAM) plate is subducting under the Caribbean plate (Figure 1). The trench region may pose significant seismic and tsunami hazards to Puerto Rico and the U.S. Virgin Islands, where 4 million U.S. citizens reside. Widespread damage in Puerto Rico and Hispaniola from an earthquake in 1787 was estimated to be the result of a magnitude 8 earthquake north of the islands. A tsunami killed 40 people in NW Puerto Rico following a magnitude 7.3 earthquake in 1918. Large landslide escarpments have been mapped on the seafloor north of Puerto Rico, although their ages are unknown. The Puerto Rico Trench is atypical of oceanic trenches. Subduction is highly oblique (10°-20°) to the trench axis with a large component of left-lateral strike-slip motion. Similar convergence geometry is observed at the Challenger Deep in the Mariana Trench, the deepest point on Earth. In addition to its extremely deep seafloor, the Puerto Rico Trench is also characterized by the most negative free-air gravity anomaly on Earth, -380 mGal, located 50 km south of the trench, where water depth is 7950 m (Figure 2). A tilted carbonate platform provides evidence for extreme vertical tectonism in the region. This platform was horizontally deposited over Cretaceous to Paleocene arc rocks starting in the Late Oligocene. Then, at 3.5 Ma, the carbonate platform was tilted by 4° toward the trench over a time period of less than 40 kyr, such that its northern edge is at a depth of 4000 m and its reconstructed elevation on land in Puerto Rico is at +1300 m (Figures 1 and 2).

ten Brink, Uri; Danforth, William; Polloni, Christopher; Andrews, Brian; Llanes, Pilar; Smith, Shepard; Parker, Eugene; Uozumi, Toshihiko

2004-09-01

113

Near Real-time Operational Use of eMODIS Expedited NDVI for Monitoring Applications and Famine Early Warning  

NASA Astrophysics Data System (ADS)

The Famine Early Warning Systems Network (FEWS NET) has requirements for near real-time monitoring of vegetation conditions for food security applications. Accurate and timely assessments of crop conditions are an important element of food security decision making. FEWS NET scientists at the U.S. Geological Survey (USGS) Earth Resources Observation and Science (EROS) Center are utilizing a new Moderate Resolution Imaging Spectroradiometer (MODIS) Normalized Difference Vegetation Index (NDVI) dataset for operational monitoring of crop and pasture conditions in parts of the world where food availability is highly dependent on subsistence agriculture and animal husbandry. The expedited MODIS, or eMODIS, production system processes NDVI data using MODIS surface reflectance provided by the Land Atmosphere Near-real-time Capability for EOS (LANCE). Benefits of this production system include customized compositing schedules, near real-time data availability, and minimized re-sampling. FEWS NET has implemented a 10-day compositing scheme every five days to accommodate the need for timely information on vegetation conditions. The data are currently being processed at 250-meter spatial resolution for Central America, Hispaniola, and Africa. Data are further enhanced by the application of a temporal smoothing filter which helps remove contamination due to clouds and other atmospheric effects. The results of this near real-time monitoring capability have been the timely provision of NDVI and NDVI anomaly maps for each of the FEWS NET monitoring regions and the availability of a consistently processed dataset to aid crop assessment missions and to facilitate customized analyses of crop production, drought, and agro-pastoral conditions.

Rowland, J.; Budde, M. E.

2010-12-01

114

Paleogeography of Jurassic fragments in the Caribbean  

NASA Astrophysics Data System (ADS)

Jurassic rocks of the Caribbean are a sampling of 100 million years of Farallon Plate history with fragments originating at diverse paleolatitudes and from varied tectonic settings. Fragments with clear paleogeographic signatures are components of the basement complexes of Duarte in Hispaniola, Bermeja in Puerto Rico and La Désirade off Guadeloupe. Paleolatitudinally sensitive radiolarian faunas document origination of Duarte as equatorial, La Désirade as higher latitude, and various Bermeja cherts as both equatorial and higher latitude. Red ribbon chert of Duarte and Bermeja of the same age, physical appearance, and lithological association are probably dismembered components of the same slab of Pacific crust. La Désirade red ribbon chert is slightly younger than the Duarte and Bermeja red ribbon chert and was deposited at higher latitude. Bermeja tuffaceous chert is also of higher latitude and probably had an arc-proximal origin. On the basis of modeled plate trajectories in the Pacific, the origin of various cherts from different paleolatitudes that end up in the same location requires different arrival times at the trench between North and South America. Based on radiolarian paleobiogeography plus indications of origin at a spreading ridge and ignoring the poorly constrained, modeled trajectories for the Late Jurassic, at least one of the higher latitude fragments may have originated in the southern hemisphere. The accumulation of multifarious chert, greenstone, and other ocean floor components was accomplished by offscraping strata transported to the subduction zone along the eastern Pacific margin and warehousing this material in an accretionary complex prior to entry of the Caribbean Plate into the gap between North and South America.

Montgomery, Homer; Pessagno, Emile A.; Lewis, John F.; Schellekens, Johannes

1994-06-01

115

Chronology of the Pueblo Viejo epithermal gold-silver deposit, Dominican Republic: formation in an Early Cretaceous intra-oceanic island arc and burial under ophiolite  

NASA Astrophysics Data System (ADS)

The Pueblo Viejo deposit (production to 1996: 166 t Au, 760 t Ag) is located in the Dominican Republic on the Caribbean island of Hispaniola and ranks as one of the largest high-sulfidation/acid-sulfate epithermal deposits (reserves in 2007: 635 t Au, 3,648 t Ag). One of the advanced argillic ore bodies is cut by an inter-mineral andesite porphyry dike, which is altered to a retrograde chlorite-illite assemblage but overprinted by late-stage quartz-pyrite-sphalerite veins and associated low-grade Au, Ag, Zn, Cd, Hg, In, As, Se, and Te mineralization. The precise TIMS U-Pb age (109.6 ± 0.6 Ma) of the youngest zircon population in this dike confirms that the deposit is part of the Early Cretaceous Los Ranchos intra-oceanic island arc. Intrusion-related gold-sulfide mineralization took place during late andesite-dacite volcanism within a thick pile (>200 m) of carbonaceous sand- and siltstones deposited in a restricted marine basin. The high-level deposit was shielded from erosion after burial under a late Albian (109-100 Ma) ophiolite complex (8 km thick), which was in turn covered by the volcano-sedimentary successions (>4 km) of a Late Cretaceous-Early Tertiary calc-akaline magmatic arc. Estimates of stratigraphic thickness and published alunite, illite, and feldspar K-Ar ages and closure temperatures (alunite 270 ± 20°C, illite 260 ± 30°C, K-feldspar 150°C) indicate a burial depth of about 12 km at 80 Ma. During peak burial metamorphism (300°C and 300 MPa), the alteration assemblage kaolinite + quartz in the deposit dehydrated to pyrophyllite. Temperature-time relations imply that the Los Ranchos terrane then cooled at a rate of 3-4°C/Ma during slow uplift and erosion.

Mueller, Andreas G.; Hall, Gregory C.; Nemchin, Alexander A.; O'Brien, Darren

2008-11-01

116

Slip rate and earthquake recurrence along the central Septentrional fault, North American-Caribbean plate boundary, Dominican Republic  

USGS Publications Warehouse

The Septentrional fault zone (SFZ) is the major North American-Caribbean, strike-slip, plate boundary fault at the longitude of eastern Hispaniola. The SFZ traverses the densely populated Cibao Valley of the Dominican Republic, forming a prominent scarp in alluvium. Our studies at four sites along the central SFZ are aimed at quantifying the late Quaternary behavior of this structure to better understand the seismic hazard it represents for the northeastern Caribbean. Our investigations of excavations at sites near Rio Cenovi show that the most recent ground-rupturing earthquake along this fault in the north central Dominican Republic occurred between A.D. 1040 and A.D. 1230, and involved a minimum of ???4 m of left-lateral slip and 2.3 m of normal dip slip at that site. Our studies of offset stream terraces at two locations, Rio Juan Lopez and Rio Licey, provide late Holocene slip rate estimates of 6-9 mm/yr and a maximum of 11-12 mm/yr, respectively, across the Septentrional fault. Combining these results gives a best estimate of 6-12 mm/yr for the slip rate across the SFZ. Three excavations, two near Tenares and one at the Rio Licey site, yielded evidence for the occurrence of earlier prehistoric earthquakes. Dates of strata associated with the penultimate event suggest that it occurred post-A.D. 30, giving a recurrence interval of 800-1200 years. These studies indicate that the SFZ has likely accumulated elastic strain sufficient to generate a major earthquake during the more than 800 years since it last slipped and should be considered likely to produce a destructive future earthquake.

Prentice, C. S.; Mann, P.; Pena, L. R.; Burr, G.

2003-01-01

117

The 2010 Haiti earthquake sequence: new insight of the tectonic pattern from aftershocks and marine geophysical data : Haiti-OBS cruise  

NASA Astrophysics Data System (ADS)

The devastating 2010 Haiti earthquake ruptured only a relatively short segment (~50km) of the Enriquillo-Plantain Garden fault (EPGF) a 600km long strike-slip fault running onland and offshore from Jamaica to Dominican Republic, with apparently no major surface rupture in the epicentral area. Considering the general behavior of such strike-slip fault (i.e. North Anatolian fault, San Andreas fault), we can expect that, following the 2010 earthquake, other large earthquakes will occur in the near future on adjacent segments. To contribute to the multinational scientific effort for a better understanding of the rupture process and the stress relaxation of this earthquake, we organized the Haiti-OBS cruise of the R/V L'Atalante few weeks after the catastrophe (Feb.5 to Feb.15, 2010, from and to Pointe-a-Pitre, Guadeloupe). Our goal was 1) to deploy a temporary network of seismologic stations -21 OBS, Ocean Bottom Seismometer, and 4 onland stations- and 2) to survey the detailed sea-floor features in relation with the deformation pattern of the area (multibeam bathymetry and mud-penetrator). We show that the distribution pattern of the aftershocks as well as the compressive surface structures observed in the geology and onshore/offshore morphology of the area are consistent with a deformation model implying a major left-lateral component along the EPGF, and a strong reverse component. The January 12, 2010 mainshock has been shown as very complex. However, in the first order, the mainshock and the distribution of the aftershocks, better localized by our temporary network, can be explained by the interaction between the strike-slip EPGF system and a blind folds-and-thrusts system. Thus, the general geological setting shows a southern extension until the southern part of the Canal du Sud area of the well-known fold and thrust system of the Hispaniola main block.

Mercier de Lepinay, B. F.; Mazabraud, Y.; Klingelhoefer, F.; Clouard, V.; Hello, Y.; Graindorge, D.; Marcaillou, B.; Crozon, J.; Saurel, J.; Charvis, P.; Mildor, B. S.; Deschamps, A.; Bouin, M.; Perrot, J.

2010-12-01

118

Tsunami hazard in the Caribbean: Regional exposure derived from credible worst case scenarios  

NASA Astrophysics Data System (ADS)

The present study documents a high tsunami hazard in the Caribbean region, with several thousands of lives lost in tsunamis and associated earthquakes since the XIXth century. Since then, the coastal population of the Caribbean and the Central West Atlantic region has grown significantly and is still growing. Understanding this hazard is therefore essential for the development of efficient mitigation measures. To this end, we report a regional tsunami exposure assessment based on potential and credible seismic and non-seismic tsunamigenic sources. Regional tsunami databases have been compiled and reviewed, and on this basis five main scenarios have been selected to estimate the exposure. The scenarios comprise two Mw8 earthquake tsunamis (north of Hispaniola and east of Lesser Antilles), two subaerial/submarine volcano flank collapse tsunamis (Montserrat and Saint Lucia), and one tsunami resulting from a landslide on the flanks of the Kick'em Jenny submarine volcano (north of Grenada). Offshore tsunami water surface elevations as well as maximum water level distributions along the shore lines are computed and discussed for each of the scenarios. The number of exposed people has been estimated in each case, together with a summary of the tsunami exposure for the earthquake and the landslide tsunami scenarios. For the earthquake scenarios, the highest tsunami exposure relative to the population is found for Guadeloupe (6.5%) and Antigua (7.5%), while Saint Lucia (4.5%) and Antigua (5%) have been found to have the highest tsunami exposure relative to the population for the landslide scenarios. Such high exposure levels clearly warrant more attention on dedicated mitigation measures in the Caribbean region.

Harbitz, C. B.; Glimsdal, S.; Bazin, S.; Zamora, N.; Løvholt, F.; Bungum, H.; Smebye, H.; Gauer, P.; Kjekstad, O.

2012-04-01

119

Site-specific Earthquake-generate Tsunami Hazard Assessment in U.S. Atlantic Coast  

NASA Astrophysics Data System (ADS)

The Indian Ocean tsunami of 24 December 2004 has changed the perception of a tsunami as an infrequent low-risk hazard. The devoid of subduction or convergent zones in the Atlantic Ocean makes coastal communities less aware of the potential tsunami hazard in the East Coast of US. The existing continental shelf offshore has believed to act as additional buffer that may significantly attenuate the tsunami impact to the U.S. Atlantic coast. However, the uncertainties are still substantial and need to be timely addressed: 1. the largest tsunami ever recorded in Atlantic, 1755 Lisbon, was understudied; 2. the Hispaniola-Puerto Rico-Lesser Antilles subduction zone - a Sumatra-Andaman type of trench - in the northeast of Caribbean is capable of generating catastrophic tsunami; 3. the South Sandwich Trench was mostly overlooked; and 4. most of previous studies tackling these issues did not surpass the linear tsunami propagation in the deep ocean for nonlinear tsunami inundation modeling in the coastal area. Using the established NOAA high-resolution tsunami inundation model, the present study explores above uncertainties and provides comprehensive modeling assessment of the potential earthquake-generated tsunami hazard for selected coastal communities in U.S. Atlantic coasts, with highlight on over-shelf tsunami wave dynamics. This study is an extension of the USGS evaluation of earthquake-tsunami impact in Atlantic (ten Brink et al., 2007; Barkan et al., 2009) in the light of the Nuclear Regulation Commission (NRC) efforts on tsunami risk assessment for existing and potential nuclear power plants in U. S. East Coast.

Wei, Y.; Titov, V. V.; Moore, C. W.; Gica, E.; Arcas, D.; Spillane, M. C.; Zhou, H.

2009-12-01

120

Benefits of studies of overwintering birds for understanding resident bird ecology and promoting development of conservation capacity.  

PubMed

Funding of ecological research and monitoring of Neotropical migratory birds on their overwintering grounds has benefited both migratory and permanent-resident species. Using examples from our work in Puerto Rico and the Dominican Republic, we demonstrate that ecological research of overwintering migrants often provides information about the ecology and demography of little-known tropical resident birds. Critically important long-term monitoring in Puerto Rico with a focus on winter residents has provided information on the relationships between annual rainfall and fluctuations in resident bird populations and survival rates. It also has alerted local biologists to declines in resident bird populations, including a decline apparently driven by the entry of a brood parasite. But migrant-focused research may also have had an underappreciated effect on the development of conservation capacity and conservation efforts in host countries. Investments in research on Neotropical migrants overwintering on Hispaniola have resulted in a huge increase in field training of students and wildlife professionals, promoted conservation awareness at local and national levels, played an important role in the growth and professionalization of key environmental organizations, spawned a growing ecotourism industry for bird-watching, and driven national park management planning and conservation efforts for all bird species. We encourage funding organizations and agencies to consider the broader impacts of funding migratory-bird research and monitoring efforts, and we encourage researchers in the tropics to use protocols that provide the most information about all the birds that use the study areas involved and to be aware of important opportunities that they may have to build capacity in host countries. PMID:19016823

Latta, Steven C; Faaborg, John

2008-11-02

121

Large-Scale Introgression Shapes the Evolution of the Mating-Type Chromosomes of the Filamentous Ascomycete Neurospora tetrasperma  

PubMed Central

The significance of introgression as an evolutionary force shaping natural populations is well established, especially in animal and plant systems. However, the abundance and size of introgression tracts, and to what degree interspecific gene flow is the result of adaptive processes, are largely unknown. In this study, we present medium coverage genomic data from species of the filamentous ascomycete Neurospora, and we use comparative genomics to investigate the introgression landscape at the genomic level in this model genus. We revealed one large introgression tract in each of the three investigated phylogenetic lineages of Neurospora tetrasperma (sizes of 5.6 Mbp, 5.2 Mbp, and 4.1 Mbp, respectively). The tract is located on the chromosome containing the locus conferring sexual identity, the mating-type (mat) chromosome. The region of introgression is confined to the region of suppressed recombination and is found on one of the two mat chromosomes (mat a). We used Bayesian concordance analyses to exclude incomplete lineage sorting as the cause for the observed pattern, and multilocus genealogies from additional species of Neurospora show that the introgression likely originates from two closely related, freely recombining, heterothallic species (N. hispaniola and N. crassa/N. perkinsii). Finally, we investigated patterns of molecular evolution of the mat chromosome in Neurospora, and we show that introgression is correlated with reduced level of molecular degeneration, consistent with a shorter time of recombination suppression. The chromosome specific (mat) and allele specific (mat a) introgression reported herein comprise the largest introgression tracts reported to date from natural populations. Furthermore, our data contradicts theoretical predictions that introgression should be less likely on sex-determining chromosomes. Taken together, the data presented herein advance our general understanding of introgression as a force shaping eukaryotic genomes.

Menkis, Audrius; Whittle, Carrie A.; Andersson, Siv G. E.; Johannesson, Hanna

2012-01-01

122

Modeling of tsunamis and hurricanes as causes of the catastrophic overwash of Anegada, British Virgin Islands, between 1650 and 1800  

NASA Astrophysics Data System (ADS)

The giant 2004 Aceh-Andaman earthquake and its Indian Ocean tsunami have spurred reassessment of earthquake and tsunami potential at subduction zones worldwide. Some of these zones resemble the source area of the 2004 earthquake in having a highly oblique convergence and little or no written record of great (M 8.0 or larger) thrust earthquakes. Some scientists have questioned whether subduction rate and subducting-plate age control the maximum earthquake size (Stein and Okal, 2007), even stating that all subduction zones long enough to make a giant (M 9) earthquake should be assumed capable of doing so (McCaffrey, 2008). In the present study, we seek to explain geological evidence for overwash, sometime between 1650 and 1800, at Anegada, northeast of Puerto Rico and 120 km south of the Puerto Rico Trench. Anegada offers three kinds of well-preserved evidence for a one-time overwash from the island’s north side during the decades between 1650 and 1800: dozens of elongate breaches cutting through sandy beach ridges of Anegada's north shore, which is protected from storm waves by a fringing reef; a sheet of sand and shell traced as much as 1.5 km southward inland from that shore; and fields of scattered boulders and cobbles moved southward and derived, in one case, from limestone outcrops 1 km south of the shore. Here we use tsunami modeling, tied to geological and written observations, to explore the earthquake and tsunami potential of the northern Antilles subduction zone. The plate convergence here is highly oblique, and there is no compelling written evidence, nor any instrumental evidence, for the occurrence of a great earthquake along the Puerto Rico Trench east of Hispaniola. We present tsunami simulations for four hypothetical sources, three along the Puerto Rico Trench and one in the Azores-Gibraltar convergence zone. We compare the model output with inundation inferred from the overwash evidence and with tsunamis, or their absence, recorded in writing in the northeast Caribbean. Alternatively, we use models of storm surge and storm waves to ask whether this overwash could have resulted from a hurricane of category 4 or 5. The models show that the fringing reef and the shallows behind it reduce storm-wave heights as much as twenty-fold and storm-wave energy by factors as large as 400. Based on these findings, along with inferences made directly from the geology itself, we conclude that the overwash at Anegada most likely resulted from the 1755 Lisbon earthquake or from a previously unreported earthquake on the outer rise along the Puerto Rico Trench.

Wei, Y.; ten Brink, U. S.; Atwater, B. F.

2010-12-01

123

Evolution of type 2 vaccine derived poliovirus lineages. Evidence for codon-specific positive selection at three distinct locations on capsid wall.  

PubMed

Partial sequences of 110 type 2 poliovirus strains isolated from sewage in Slovakia in 2003-2005, and most probably originating from a single dose of oral poliovirus vaccine, were subjected to a detailed genetic analysis. Evolutionary patterns of these vaccine derived poliovirus strains (SVK-aVDPV2) were compared to those of type 1 and type 3 wild poliovirus (WPV) lineages considered to have a single seed strain origin, respectively. The 102 unique SVK-aVDPV VP1 sequences were monophyletic differing from that of the most likely parental poliovirus type 2/Sabin (PV2 Sabin) by 12.5-15.6%. Judging from this difference and from the rate of accumulation of synonymous transversions during the 22 month observation period, the relevant oral poliovirus vaccine dose had been administered to an unknown recipient more than 12 years earlier. The patterns of nucleotide substitution during the observation period differed from those found in the studied lineages of WPV1 or 3, including a lower transition/transversion (Ts/Tv) bias and strikingly lower Ts/Tv rate ratios at the 2(nd) codon position for both purines and pyrimidines. A relatively low preference of transitions at the 2(nd) codon position was also found in the large set of VP1 sequences of Nigerian circulating (c)VDPV2, as well as in the smaller sets from the Hispaniola cVDPV1 and Egypt cVDPV2 outbreaks, and among aVDPV1and aVDPV2 strains recently isolated from sewage in Finland. Codon-wise analysis of synonymous versus non-synonymous substitution rates in the VP1 sequences suggested that in five codons, those coding for amino acids at sites 24, 144, 147, 221 and 222, there may have been positive selection during the observation period. We conclude that pattern of poliovirus VP1 evolution in prolonged infection may differ from that found in WPV epidemics. Further studies on sufficiently large independent datasets are needed to confirm this suggestion and to reveal its potential significance. PMID:23840537

Hovi, Tapani; Savolainen-Kopra, Carita; Smura, Teemu; Blomqvist, Soile; Al-Hello, Haider; Roivainen, Merja

2013-06-28

124

Upper Ocean Responses to Hurricane Frances in September 2004  

NASA Astrophysics Data System (ADS)

Three new autonomous ocean velocity and density profilers were deployed ahead of Hurricane Frances as it passed north of Hispaniola in September 2004. These EM-APEX floats (velocity sensing versions of Webb Research Corp APEX floats) were launched from a C-130. The EM-APEX floats measured T, S and V over the upper 500 m starting about a day before the storm's arrival. One EM-APEX float was directly under the track of the storm's eye, another EM-APEX float went in about 55 km to the right of the track (where the surface winds are strongest) and the third float was about 110 km to the right. The EM-APEX floats profiled for 10 hours from the surface to 200 m then continued profiling between 30 and 200 m with excursions to 500 m every half inertial period. After 5 days, the EM-APEX floats surfaced and transmitted the accumulated processed observations, then the floats profiled to 500 m every half inertial period until recovered early in October aided by GPS and Iridium. The float array sampled in unprecedented detail the upper-ocean momentum, turbulence and salt and heat changes in response to the hurricane. Rapid acceleration of inertial currents in the surface mixing layer (SML) to over 1 m/s produced vertical mixing by shear instability at the SML base, as indicated by low Richardson numbers and SML deepening from about 40 m to 120 m under the strongest wind forcing. Surface cooling of about 2.2 C was primarily due to the SML deepening and entrainment of colder water, with a small contribution from surface heat flux. Intense inertial pumping was observed under the eye, with vertical excursions of 50 m or more. Comparison with a 3-D numerical model of the ocean response to Frances' winds simulates accurately SML deepening and surface cooling as well as significant differences in maximum currents and heat content changes. These differences highlight the sensitivity of the ocean's response to both the specification of the wind field and the parameterization of stress under high wind speeds. In particular, the momentum flux into the ocean supports a drag coefficient that does not increase with wind speed as proposed by recent GPS dropsonde and wind-wave tank studies.

Sanford, T. B.; Price, J. F.; Webb, D. C.; Girton, J. B.

2007-05-01

125

Evolution of Type 2 Vaccine Derived Poliovirus Lineages. Evidence for Codon-Specific Positive Selection at Three Distinct Locations on Capsid Wall  

PubMed Central

Partial sequences of 110 type 2 poliovirus strains isolated from sewage in Slovakia in 2003–2005, and most probably originating from a single dose of oral poliovirus vaccine, were subjected to a detailed genetic analysis. Evolutionary patterns of these vaccine derived poliovirus strains (SVK-aVDPV2) were compared to those of type 1 and type 3 wild poliovirus (WPV) lineages considered to have a single seed strain origin, respectively. The 102 unique SVK-aVDPV VP1 sequences were monophyletic differing from that of the most likely parental poliovirus type 2/Sabin (PV2 Sabin) by 12.5–15.6%. Judging from this difference and from the rate of accumulation of synonymous transversions during the 22 month observation period, the relevant oral poliovirus vaccine dose had been administered to an unknown recipient more than 12 years earlier. The patterns of nucleotide substitution during the observation period differed from those found in the studied lineages of WPV1 or 3, including a lower transition/transversion (Ts/Tv) bias and strikingly lower Ts/Tv rate ratios at the 2nd codon position for both purines and pyrimidines. A relatively low preference of transitions at the 2nd codon position was also found in the large set of VP1 sequences of Nigerian circulating (c)VDPV2, as well as in the smaller sets from the Hispaniola cVDPV1 and Egypt cVDPV2 outbreaks, and among aVDPV1and aVDPV2 strains recently isolated from sewage in Finland. Codon-wise analysis of synonymous versus non-synonymous substitution rates in the VP1 sequences suggested that in five codons, those coding for amino acids at sites 24, 144, 147, 221 and 222, there may have been positive selection during the observation period. We conclude that pattern of poliovirus VP1 evolution in prolonged infection may differ from that found in WPV epidemics. Further studies on sufficiently large independent datasets are needed to confirm this suggestion and to reveal its potential significance.

Hovi, Tapani; Savolainen-Kopra, Carita; Smura, Teemu; Blomqvist, Soile; Al-Hello, Haider; Roivainen, Merja

2013-01-01

126

Two-stage Extensional Opening of the Mona Passage as Revealed by New Multibeam Bathymetry and Seismic Reflection Data  

NASA Astrophysics Data System (ADS)

The Mona Passage, located between Puerto Rico (P.R.) and the Dominican Republic (D.R.), has long been considered a region of significant extensional deformation resulting from the oblique subduction system active along the northern Caribbean plate boundary. Published analyses of GPS data show that extension in this region continues today, with P.R. moving northeasterly away from Hispaniola at a rate of between 3-4 mm/yr, maintaining the active extensional environment between these islands. High-resolution EM 1002 swath bathymetry and multi-channel seismic reflection profiles collected in the Mona Passage in March 2007 and October 2006 respectively have for the first time clearly revealed the nature of extensional deformation within this seismically active region. These new data, combined with data from several recent bathymetry surveys in the region show a complex morphostructural terrane, comprising a mix of fault-, erosional-, and landslide-related morphologies. Flat-lying and northward- and southward-backtilted fault blocks, capped by Oligocene to Holocene aged carbonate units, dominate the seafloor and sub-seafloor landscape. At the seafloor, the fault blocks are in places eroded by the powerful bottom currents passing through the passage, while in the subsurface, they form extensional basins, covered by variable thicknesses of young sediments. The most prominent of these fault blocks is the north-dipping Desecheo Ridge, where as much as 700 m of carbonate and Cretaceous-lower Oligocene volcanic and basement units are exposed on its southern side along the multi-stranded southward- dipping Desecheo Ridge fault. The Desecheo Ridge fault extends from near Punta Higuero on the west coast of P.R. to Desecheo Island, where is steps approximately 1.5 km south and continues westward. Exposed on the seafloor and in the shallow subsurface are two dominant fault sets of differing orientations; a N- to NNW-oriented set and a W- to WNW-oriented set. The N- to NNW-striking faults are typically shorter, deeply eroded, and in many places such as at the southwest corner of Mona Canyon, curve along strike. Faults in the W- to WNW-oriented set, cross-cut the N- to NNW-set and in many places cut the overlying sediment cover, indicating that they are the younger, active faults. To date, no definitive piercing-points or other evidence of lateral or oblique movement have been identified along any of the faults in the passage, suggesting that most if not all of the current motion on these faults may be extensional. The perpendicular direction to the active fault set (NNE-SSW), while similar to the relative motion between the eastern D.R. and western P.R. given from GPS, is at odds with the E-W extension direction implied by the Mona Rift. Several of the long E-W striking faults extend along much of the approximately 125 km width of the passage, some of which appear to be continuations of sub-aerially exposed faults identified in western P.R., such as Cerro Goden and Mayaguez faults. The length of these faults and the presence of other major, and likely active, faults in close proximity to the coasts of P.R. and the D.R., make an understanding of these individual faults and wider structural fabric of the region important for seismic hazard analysis. In terms of the tectonic history of the region, the presence of two distinct fault orientations of differing ages in the passage may reflect a moderate shift in plate motion during the current stage of extensional opening or a record of the current and an earlier (Miocene-Pliocene?) stage of deformation.

Chaytor, J. D.; ten Brink, U. S.

2007-12-01

127

Rapid Detection of Coseismic Displacements with PALSAR ScanSAR-ScanSAR Interferometry  

NASA Astrophysics Data System (ADS)

On large earthquake disasters, researchers and disaster managers eager to grasp the over-all image of the event immediately with as high resolution as possible. The rapid detection of coseismic deformation enables us to discriminate co- and postseismic deformations and estimate fault parameters, which definitely contributes to the evaluation of stress transfer which leads to aftershock forecast. The ScanSAR-ScanSAR interferometry is one of techniques that can provide information on coseismic displacement field in a wide region. Phased Array-type L-band SAR (PALSAR) onboard Japan’s Advanced Land Observation Satellite (ALOS) is capable to make an observation with ScanSAR mode with as wide swath as 350km. Owing to its long wavelength, coherence is high enough to perform interferometry in vegetated areas and steep mountains. We have applied this technique to images acquired before and after 4 events that occurred this year. We use the full-aperture algorithm to produce single look complex images for each swath and apply usual 2-pass interferometry to SLC’s. It is quite important to synchronize bursts of two ScanSAR images for interferometry, but this could be done only by the Japan Aerospace Exploration Agency (JAXA). Our first trial was the Haiti earthquake of January, 2010. After its occurrence, we requested JAXA to acquire a ScanSAR image of the western Hispaniola Island. On February 11, the acquisition was made. JAXA synchronized its bursts to the image acquired on Sept. 26, 2009. We observed coseismic fringes near the epicenter along the Enriquillo fault similar to those obtained from strip-map mode images. On the other hand, no notable deformation was found near the Septentrional fault, northern Haiti. The second example was the Chile earthquake of February 27, 2010. Post-earthquake observation was made on March 1, 2010. The observed area was as wide as 350km, from the Pacific coast to the eastern frank of the Andes, and as long as 1000km. This image was synchronized to that acquired on April 10, 2008. We found maximum 3m range increases in parallel to the coast line from Valparaiso to the south of Concepcion. Since the acquisition was made from the descending track, this observation implies large oceanward shift or subsidence in this region. We also notify that there are two centers of concentric fringes at 35S and 37S, which suggests there are two asperities. We also analyzed images of consecutive acquisition and detected postseismic deformation as well as coseismic deformation from the largest aftershock during one and half month. We also analyzed images from Baja California, Mexico, and Quinghai, China. These results are also presented in association with necessary conditions on successful interferometry.

Hashimoto, M.; Ozawa, T.; Tobita, M.; Miyawaki, M.; Shimada, M.

2010-12-01

128

A Seismo-Tectonic Signal From Offshore Sedimentation: The 2010 Haiti Earthquake and Prior Events  

NASA Astrophysics Data System (ADS)

The Mw 7.0 January 2010 earthquake in Haiti was one of the deadliest in history. It involved multiple faults along or near the main Enriquillo-Plantain Garden Fault (EPGF). This left-lateral transform is a branch of the northern Caribbean plate boundary across southern Hispaniola. The main rupture was strike-slip but almost all aftershocks had thrust mechanisms, and surface deformation may have been concentrated on anticline forelimbs driven by blind thrust faults. Earthquake generated mass-wasting and turbidity currents were sampled from the Canal du Sud slope (~1000 m water depth), a basin at 1500 m, and the deepest part of the strait at 1700 m. The turbidites were strongly correlated by 234Th with a half-life of 24 days. In the deepest area, a turbidite-homogenite unit (T-H) extends over 50 km2 and is composed of basal sand beds 5 cm thick and 50 cm of mud above. The sedimentary structures in the sand were linked to oscillatory motions by internal seiches. The T-H units recovered from the slope and deep basin are similar in composition. The Leogane Delta, upslope from the sampling sites, is rich in this lithology that has been linked to oceanic basement rocks exposed on the southern Haitian peninsula. In contrast, the T-H unit recovered from the basin at 1500 m is perched behind a thrust anticline and has a greater concentration of Ca derived from Ca rich sources such as the Tapion Ridge on the southern peninsula. The Tapion Ridge is a compressional structure associated with a restraining bend along the EPGF. The T-H unit beneath the 2010 deposit has a 14C age of 2400 cal yrs BP, and interpreted as an earthquake triggered deposit. It is nearly identical in thickness, composition and fine structures to the 2010 T-H. Notably absent from the record are younger turbidites that could have been linked to the historic 1770 AD and other similar earthquakes expected from GPS rates across the EPGF. Two hypotheses are being considered for this long gap in T-H sedimentation. One proposes that during relative high stands of sea level fringing reefs are trapping sediment on the shelf and that a critical accumulation is needed to generate failure. Many large local earthquakes could have occurred before reaching this critical thickness. Low sedimentation rates (6 cm/1000 yrs) support this possibility. Our preferred hypothesis, alternatively, links T-Hs to earthquakes with a large thrust component such as the 2010 event in order to generate failure. This latter hypothesis accounts for some earthquakes producing no turbidites while others, such as the 2010 event, do. It also accounts for the fracturing sampled along 8 km of the perched basin. We propose that thrust earthquakes along the Tapion Ridge segment of the EPGF reoccur at ~2000-year intervals and this sedimentary signal is preserved in Canal du Sud.

McHugh, C. M.; Seeber, L.; Cormier, M.; Hornbach, M.; Momplaisir, R.; Waldhauser, F.; Sorlien, C. C.; Steckler, M. S.; Gulick, S.

2011-12-01

129

The Role of Science and Engineering in Rebuilding a More Resilient Haiti (Invited)  

NASA Astrophysics Data System (ADS)

Rebuilding a more disaster-resilient Haiti is the defining challenge in the wake of the devastating magnitude-7 earthquake that struck in January. The contrasting experience of Chile, which weathered a magnitude-8.8 earthquake in April with casualties in the hundreds, teaches us that building resilience is an achievable and desirable goal given suitable investments and governance. Scientists and engineers have much to contribute, but doing so requires effective mechanisms to enable them to inform the rebuilding process. The international donor community has been a key point of engagement since their funds provide the opportunity to build new schools, hospitals, critical infrastructure and housing that will not fail in the next disaster. In advance of a gathering of international donors at the end of March, the U.S. National Science and Technology Council’s interagency Subcommittee on Disaster Reduction convened a workshop that brought together over 100 scientists, engineers, planners, and policymakers, including a delegation of Haitian government officials and academics. Hosted by the University of Miami and organized by the Incorporated Research Institutions for Seismology, the workshop was co-sponsored by the U.S. Department of State, U.S. Agency for International Development (USAID), and United Nations International Strategy for Disaster Reduction with support from NASA, the National Science Foundation, and the U.S. Geological Survey (USGS). Key findings from the workshop covered the need to adopt and enforce international building codes, to use hazard assessments for earthquakes, inland flooding, and landslides in the planning process, and the central importance of long-term capacity building. As an example of one science agency’s contributions, the USGS informed the initial response by rapidly characterizing the earthquake and delivering estimates of population exposure to strong shaking that were used by humanitarian organizations, aid agencies, and the Haitians themselves. In the ensuing weeks, the USGS tracked aftershocks and issued statements with probabilities of future earthquakes. Early on, the U.S. Southern Command made it possible to put an advance team of engineers and a USGS seismologist on the ground in Haiti. That initial team was followed by the first major deployment of a USGS/USAID Earthquake Disaster Assistance Team, which evolved from the long-standing partnership between these two agencies. EDAT activities included field assessment of faulting, coastal uplift, and landslides; seismometer deployments for aftershock recording and characterization of ground shaking amplification; and development of a probabilistic seismic hazard map for Haiti and the whole island of Hispaniola. The team’s efforts benefited greatly from collaboration with Haitian colleagues with knowledge transfer occurring in both directions. The effort also benefited from significant remote sensing acquisitions, which helped to target field activities and constrain fault rupture patterns. Although the products have been put to use in Haiti, it still remains to turn hazard assessments into tools that can be used for effective planning, building code development and land-use decisions.

Applegate, D.

2010-12-01

130

Some Aspects of the Physical Variability of the Caribbean Sea Relevant to Regional Climate Variability  

NASA Astrophysics Data System (ADS)

The Caribbean Sea is the least studied portion of the Intra-Americas Sea (IAS), which is the combined Caribbean Sea, Gulf of Mexico, Straits of Florida, and the adjacent western North Atlantic. The upstream elements of the Gulf Stream System are the dominant features of the upper ocean circulation in the Caribbean Sea. The Trade Winds superimpose a coastal upwelling regime along the northern coast of South America and a coastal downwelling regime along the southern coasts of Cuba and Hispaniola. The inflow from the Atlantic through several Antillean passages is derived from tropical and subtropical sources and is relatively weak, shallow, and variable; the outflow to the Gulf of Mexico through the Yucatan Channel is relatively strong, deep, and variable. The variability includes mesoscale eddies and meanders as well as the seasonal cycle and year-to-year variability; it also includes lengthy plumes from the Orinoco and other rivers and lengthy filaments from coastal upwelling centers. Some of the mesoscale variability originates in the Eastern Caribbean; other components originate in the Western Caribbean, especially in the cyclonic Panama-Colombia Gyre. The upper ocean of the Caribbean Sea is not only under the influence of the Trade Winds and their seasonal and longer term variability but also two other, not mutually exclusive, sources of variability: the seasonal heating and precipitation cycles on one hand, and synoptic scale and mesoscale phenomena on the other hand. For example, there are wet and dry seasons, and the Eastern Caribbean is typically dry and the Western Caribbean typically wet, with a heavy rainfall zone off the coast of Central America. And the patterns of atmospheric deep convection and subsidence apparently account for the summertime intensification of an extensive "warm pool" concentrated in the Northwestern Caribbean, which is exported to the Gulf of Mexico. As another example, the weekly Tropical Easterly Waves (TEWs) are the predominant synoptic atmospheric systems in the summertime, while weekly cold front passages are predominant in wintertime. Some of the TEWs develop into tropical cyclones and hurricanes, a subset of which commonly pass over the warm pool that may foster their further development. The atmospheric regime includes the Caribbean Low Level Jet (CLLJ) embedded in the Trade Winds and which may play a critical role in the summertime transport of moisture into the American Midwest. How these synoptic scale systems affect air-sea transfers in the IAS has yet to be quantified. Some of the above points are illustrated with numerical simulations using IAS-POM, an implementation of the Princeton Ocean Model with eddy-admitting resolution. Others are illustrated using information from climatology and recent observations. A challenging potential application is the scientific design of Marine Protected Areas, especially their separation distances taking into account the probable Lagrangian pathways (and rates) linking nearest neighbors through hypothetical larval transports, as illustrated by IAS-POM.

Mooers, C. N.

2001-12-01

131

MOTION UNDER THE OCEAN: Determining mantle flow of the Northeast Caribbean with seismic anisotropy  

NASA Astrophysics Data System (ADS)

Active plate boundaries in the Northeast Caribbean have formed a complex tectonic environment which includes transform and subduction zones. The Caribbean-North America plate boundary is one such active margin, where subduction transitions from arc- to oblique-type off the northeast coast of Puerto Rico. Several lines of evidence support the notion of a slab tear within the subducting North American plate at this transition zone, including the counter-clockwise rotation of the Puerto Rico microplate over the past 10 Ma and clusters of small seismic events. Understanding mantle flow in this region will not only help determine the nature of tectonic activity controlling these margins, but will also aid our understanding of anomalies, such as slab tears. Mantle flow and crustal deformation are believed to be the main controls of anisotropy in the lithosphere and asthenosphere. When a shear-wave passes through an anisotropic medium, it is split into a fast and slow component, with the fast shear-wave polarized along the fast direction of that medium. Shear-wave splitting is a tool used to determine the strength and direction of such anisotropy. Previous studies in the Caribbean have generally shown fast shear-wave polarization directions parallel to trenches and/or plate boundaries, indicating mantle flow around the plate (Growdon et al. 2009; Masy et al. 2011; Piñero-Feliciangeli and Kendall 2008). We have focused a detailed investigation of seismic anisotropy from 31 stations across six networks in the Northeast Caribbean to better constrain mantle flow in this region. Shear-wave splitting measurements of teleseismic core phases (e.g., SKS and SKKS) were completed using SplitLab, a Matlab° based environment created by Wüstefeld et al. (2008). This program enables the user to compare the quality of results from three splitting methods: rotation correlation (Bowman and Ando, 1987), minimum energy (Silver and Chan, 1991) and eigenvalue (Silver and Chan, 1991). Noisy seismic data is common to these island-based stations due to energy generated by ocean wave action. To overcome this limitation, we stacked error diagrams obtained from our split analyses to produce more robust solutions (Wolfe and Silver, 1998; Monteiller and Chevrot, 2010). A regional synthesis of our results reveals fast shear-wave polarizations that are generally oriented parallel to the plate boundary with intermediate to high split times. For example, polarization directions are oriented roughly N-S along the bulk of the Lesser Antilles, E-W along the Puerto Rico Trench and the northern Lesser Antilles, and NW-SE beneath Hispaniola. Beneath the U.S. and British Virgin Islands, however, the fast polarization direction differs markedly from the regional pattern, becoming almost perpendicular to the plate boundary. Stations on Anegada and St. Croix show a fast polarization direction that is oriented nearly N-S and smaller delay times than surrounding stations. These results suggest that mantle flow is redirected N-S at this location through a gap in the subducted lithosphere of the North American plate. This new understanding of plate geometries and mantle flow provides insight into the controls of Northeast Caribbean tectonism and to other regions around the world with proposed slab tears and gaps.

Mintz, H. E.; Pulliam, J.

2011-12-01

132

Mineral and whole rock compositions of peridotites from Loma Caribe (Dominican Republic): insights into the evolution of the oceanic mantle in the Caribbean region  

NASA Astrophysics Data System (ADS)

Several mantle peridotite massifs crop out as isolated dismembered bodies in tectonic belts along the northern margin of the Caribbean plate, especially in Cuba, Guatemala, Jamaica, Hispaniola and Puerto Rico. Among these bodies, the Loma Caribe peridotite forms the core of the Median Belt in central Dominican Republic and is considered to have been emplaced in Aptian time as result of the collision between an oceanic plateau (the Duarte plateau terrane) and the primitive Caribbean island arc. This peridotite massif is mainly composed of clinopyroxene-rich harzburgite, harzburgite, lherzolite and dunite which mainly have porphyroclastic texture with strongly deformed orthopyroxene porphyroclasts, as commonly observed in ophiolitic mantle tectonites. Mg# [100*Mg/(Mg+Fe2+)] of olivine increases from lower values in lherzolite (89-90), to higher values in harzburgite (89-91) and dunite (91-92). Orthopyroxene in harzburgite has higher Mg# (91-92) and lower Al2O3 (0.89 to 1.12 wt.%) than in lherzolite (Mg# = 89-91; Al2O3 = 2.4-3.5wt.%), similarly to clinopyroxene (Mg# = 94-95 and Al2O3 = 0.89-1.10 wt% in harzburgite, versus Mg# = 86-94 and Al2O3 = 2.3-4.0 wt% in lherzolite). Cr# [Cr/(Cr+Al)] of spinel spans from 0.30 in lherzolite to 0.88 in dunite. These variations in terms of Mg# in olivine and Cr# in spinel overlap the mineral compositions in both abyssal and supra-subduction zone peridotites. The sample/chondrite REE concentrations of peridotites are variable (0.002 < LREE chondrite-normalized < 0.11 and 0.002 < HREE chondrite-normalized < 1.02) and their HREE contents generally reflect the clinopyroxene proportions in the samples, i.e. harzburgite has lower HREE abundances than lherzolite. These trace element abundances are transitional between those of highly depleted supra-subduction peridotites from ophiolites in eastern Cuba and those of fertile mantle rocks in ultramafic massifs from Puerto Rico. Chondrite-normalized patterns are U-shaped (i.e., relatively rich in LREE) with steep fractionated HREE segments in harzburgite and hump-shaped MREE segments in lherzolite. Peridotites are enriched in the most incompatible trace elements (Cs, Rb, Ba, Th, U) and Pb, and show negative anomaly in Nb and Ta. HREE contents in whole rock indicate that the Loma Caribe peridotites are residues after moderate to high degrees (10-25%) of fractional partial melting in the spinel stability field. The relative enrichment in incompatible elements (e.g., LILE and LREE) in these rocks probably reflects the capture of percolating melt fractions along grain boundaries or as micro-inclusions in minerals and resulted from interaction of melting residues with ascending melts. We interpret the Loma Caribe peridotite as a portion of heterogeneous sub-oceanic mantle lithosphere generated in Jurassic-Cretaceous time, which has been modified at a supra-subduction zone environment related to the Cretaceous Greater Antilles arc.

Marchesi, C.; Garrido, C. J.; Proenza, J. A.; Konc, Z.; Hidas, K.; Lewis, J.; Lidiak, E.

2012-04-01

133

Geochemistry of jadeitites and jadeite-lawsonite rocks in a serpentinite mélange (Rio San Juan Complex, northern Dominican Republic): Constraints on fluid composition in a subduction channel environment  

NASA Astrophysics Data System (ADS)

Jadeitites are excellent rock types for obtaining information on fluid composition in subduction zones. Recent studies indicate that many jadeitites appear to have formed by direct precipitation from a fluid [1]. In almost all localities worldwide (see e.g. Harlow and Sorensen, 2005) jadeitites are found either as allochthonous blocks or as veins and lenses directly within the serpentinite country rock of serpentinite mélanges. In the Rio San Juan Complex on the other hand jadeitite also frequently occurs as veins (cm to some dm in thickness) within lawsonite-blueschist blocks [2,3,4] entrained in the serpentinite mélange. The mélange of the Rio San Juan Complex also contains blocks (m to 10m scale) of different metamorphic grade and lithology (eclogites, blueschists, orthogneisses and very low grade rocks) showing contrasting but interrelated P-T-t paths. The consistency of such interrelated P-T-t paths with those obtained by numerical models led Krebs et al. [5] to interpret the mélange of the Rio San Juan Complex as a former subduction channel. So far, two types of jadeitite have been found in the blueschist blocks: either as discordant veins cutting the foliation, or as concordant layers. In some cases the jadeitites contain large amounts of lawsonite and should then better be called jadeite-lawsonite rocks. The latter rock type may form a network of thin (< 1cm) veinlets that are folded. In both jadeitite and jadeite-lawsonite rocks XJd in clinopyroxene ranges between 0.80 and 0.99. The contact between vein and host rock is very sharp and petrographically no sign of a depletion zone near the vein can be recognized, indicating that the infiltrating fluid originated from an external source and was not released from the adjoining host rock. A mineralogical center-to-rim zonation has been identified in the jadeitite veins. Near the contact to the blueschist, lawsonite is the dominant mineral phase and towards the center the amount of jadeite increases. Major and trace element concentrations also change from centers to rims. Ca/Na varies from 0.75-0.77 in the center to 1.03-1.29 in the rim; the rims are enriched in Rb, Ba, Pb, Eu and have slightly higher REE concentrations than the centers. This may be explained by the lower solubility of lawsonite compared to that of jadeite [6], causing lawsonite to crystallize first during precipitation. Lawsonite crystallization leads to a decrease of the Ca/Na ratio in the fluid. When the Ca/Na ratio becomes low enough jadeite starts to crystallize. Based on chemical data, jadeitites and jadeite-lawsonite rocks can be subdivided into two groups. The chondrite-normalised REE pattern of the first group shows decreasing normalized values from LREE (40-10 times) towards HREE (8-1 times). The second group has a U-shaped pattern with a strong positive Eu (5 times) anomaly. Even though no depletion zone in the adjoining host rock of the jadeitite is petrographically visible, there are lower REE concentrations in blueschists directly adjacent to the veins as compared to homogeneous blueschists without any veins. This clearly indicates some fluid-rock interaction during formation of the veins. References 1) Harlow G.E., Sorensen S.S. (2005) Jade (nephrite and jadeitite) and serpentinite: Metasomatic connections. International Geology Review 47:113-146. 2) Schertl, H.-P., Maresch, W.V., Krebs, M., Draper, G. (2007) The Rio San Juan serpentinite complex and its jadeitites (Dominican Republic). In: Martens U., García-Casco A. (eds) High-pressure belts of Central Guatemala: the Motagua suture and the Chuacús Complex. IGCP 546 Special Contribution, 1. 3) Schertl, H.-P., Krebs, M., Maresch, W.V., Draper, G. (2007) Jadeitite from Hispaniola: a link between Guatemala and Antigua? 20th Colloquium on Latin American Earth Sciences, Kiel, Germany, Abstract Volume, 167-168 4) Baese, R., Schertl, H.-P., Maresch, W.V. (2007) Mineralogy and petrology of Hispaniolan jadeitites: first results. In: Martens U., García-Casco A. (eds) High-pressure belts of Central Guatemala: the Motagua suture and the

Baese, Rauno; Maresch, Walter V.; Schenk, Volker; Schertl, Hans-Peter

2010-05-01