No. Registros Solicitud 1 5614 colombia



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DE - DESCRIPTORS: Cenozoic-; chemical-composition; Colombia-; genesis-; geochemistry-; geochronology-; igneous-rocks; magmatism-; Mesozoic-; relative-age; rhyodacites-; rhyolites-; Serrania-de-Perija; Sierra-Nevada-de-Santa-Marta; South-America; Tertiary-; volcanic-rocks; =-

CC - CATEGORY CODES: 05A-Igneous-and-metamorphic-petrology; 03-Geochronology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

IL - ILLUSTRATION: Refs: 5; illus. incl. 26 plates, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 0370-3908

CO - CODEN: RCCFAO

AN - ACCESSION NUMBER: 2000-033579

UD - UPDATE CODE: 200011

Registro 5300 de 5614 - GeoRef 1997-2001

TI - TITLE: El terremoto de Los Muzos (1646, Abril 3) a la luz de un excepcional documento colonial, la relacion de Don Bartolome de Mazmela y Poveda

Translated Title: The Los Muzos earthquake, April 3, 1646, in the light of an exceptional colonial document, the account of Don Bartolome de Mazmela y Poveda.

AU - AUTHORS: Espinosa-Baquero-Armando

AF - AUTHOR AFFILIATION: Universidad del Quindio, Facultad de Ingenieria, Armenia, Colombia

SO - SOURCE: Revista de la Academia Colombiana de Ciencias Exactas, Fisicas y Naturales. 23; 87, Pages 205-212. 1999.

PB - PUBLISHER: Academia Colombiana de Ciencias Exactas, Fisicas y Naturales. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: Some days after the terrible earthquake which destroyed the colonial town of Los Muzos on April 3 1646, Don Bartolome de Mazmela y Poveda, a local priest, wrote an account which gives valuable information on the effects of the phenomenon. The damage caused in Los Muzos and in the whole region, the occurrence of a series of quakes during several weeks (aftershocks), and the religious ceremonies celebrated during two weeks in Los Muzos are the main subjects included in the document. The important data furnished by Don Bartolome de Mazmela allows to advancement of several ideas on the earthquake. It probably was a shallow event whose epicenter was located southwest of Muzo, within an important seismogenic area which has not received enough attention up to now. From a cultural point of view, the account reveals the tremendous impact caused on the colonial community by earthquakes, and by natural disasters in general. The total misunderstanding of their causes led the authorities and the community to interpret them in mythological terms.

DE - DESCRIPTORS: aftershocks-; Boyaca-Colombia; Cenozoic-; Colombia-; Cundinamarca-Colombia; damage-; depth-; description-; earthquakes-; epicenters-; focus-; Holocene-; Los-Muzos-Colombia; Los-Muzos-earthquake-1646; Quaternary-; seismology-; South-America

CC - CATEGORY CODES: 19-Seismology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N050000; N061500; LONG: W0733000; W0743000.

IL - ILLUSTRATION: Refs: 6; sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 0370-3908

CO - CODEN: RCCFAO

AN - ACCESSION NUMBER: 2000-033578

UD - UPDATE CODE: 200011

Registro 5301 de 5614 - GeoRef 1997-2001

TI - TITLE: Environmental history of the Colombian savannas of the Llanos Orientales since the last glacial maximum for lake records El Pinal and Carimagua.

AU - AUTHORS: Behling-Hermann; Hooghiemstra-Henry

AF - AUTHOR AFFILIATION: University of Amsterdam, Department of Palynology and Paleo/Actuo-ecology, Amsterdam, Netherlands

SO - SOURCE: Journal of Paleolimnology. 21; 4, Pages 461-476. 1999.

PB - PUBLISHER: Kluwer Academic. Dordrecht - Boston - London, Netherlands. 1999.

CP - COUNTRY OF PUBLICATION: Netherlands

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: English

DE - DESCRIPTORS: absolute-age; C-14; carbon-; Cenozoic-; Colombia-; cores-; correlation-; Holocene-; isotopes-; lacustrine-environment; Laguna-Carimagua; Laguna-El-Pinal; Laguna-Sardinas; lake-sediments; Llanos-; lower-Holocene; mass-spectra; microfossils-; miospores-; paleoecology-; paleoenvironment-; palynomorphs-; Pleistocene-; pollen-; Quaternary-; radioactive-isotopes; savannas-; sediments-; South-America; spectra-; upper-Pleistocene

CC - CATEGORY CODES: 24-Quaternary-geology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N033000; N043000; LONG: W0690000; W0740000.

IL - ILLUSTRATION: Refs: 39; illus. incl. 1 table, sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 0921-2728

AN - ACCESSION NUMBER: 2000-033551

UD - UPDATE CODE: 200011

Registro 5302 de 5614 - GeoRef 1997-2001

TI - TITLE: Geochemical evidence for island arc subduction in the Caribbean; the Villa de Cura blueschist belt, Venezuela.

AU - AUTHORS: Stiles-Layla; Sisson-Virginia; Ave-Lallemant-Hans-G

AF - AUTHOR AFFILIATION: Rice University, Department of Geology and Geophysics, Houston, TX, United States

BK - BOOK TITLE: In: Geological Society of America, 1999 annual meeting.

BA - BOOK AUTHORS: Anonymous

SO - SOURCE: Abstracts with Programs - Geological Society of America. 31; 7, Pages 114. 1999.

PB - PUBLISHER: Geological Society of America (GSA). Boulder, CO, United States. 1999.

CP - COUNTRY OF PUBLICATION: United-States

PY - PUBLICATION YEAR: 1999

CN - CONFERENCE INFORMATION: Geological Society of America, 1999 annual meeting. Denver, CO, United States. Oct. 25-28, 1999.

LA - LANGUAGE: English

AB - ABSTRACT: New geochemical data from the Villa de Cura (VdC) blueschist belt in northern Venezuela imply that it is a subducted (and exhumed) island-arc terrane. This interpretation is contrary to previous interpretations that have correlated the VdC blueschist belt with plateau basalts, possibly related to the Galapagos hot spot. The VdC is a coherent blueschist terrane composed of variable amounts of interbedded metalava, metatuff, metachert, metavolcaniclastic rocks, graphitic schists, as well as minor metabreccia and possible metaconglomerates. Major element geochemistry show that the VdC volcanic sequence is a suite of evolved magmas, much like a modern island arc, with mafic to intermediate volcanics consisting of 45.4-61.5 wt% SiO (sub 2) and average 7.3 wt% MgO. Interbedded felsic tuffs have values of 70.2-81.4 wt% SiO (sub 2) and average 12.2 wt% Al (sub 2) O (sub 3) . Our new major, trace element and REE geochemical data on mafic assemblages within the VdC exhibit signatures similar to modern island arc suites; a strongly negative Nb anomaly, flat to LREE enriched chondrite normalized REE patterns, and median incompatible element ratios of La/Yb = 2.9, La/Nb = 2.8, Th/Hf = 0.4, and Hf/Yb = 0.8. There is limited evidence in the wide scatter of Sr, K, Rb, and Ba in MORB normalized spider diagrams for extraction of some fluid mobile elements during blueschist metamorphism at 97-88 Ma. One voluminous and ubiquitous unit within the VdC is a kilometer scale sequence of metalava, possibly a metaankaramite/picrite, with large (up to or >10 cm) relict igneous clinopyroxenes. These will be analyzed by microprobe to determine the original igneous composition of the volcanic protolith. Unmetamorphosed units similar to this one have been described throughout the Caribbean margin in Hispaniola, Curacao, Aruba, Colombia, Tobago, and Costa Rica. We suggest the island arc that was the hypothesized source of this suite was active in mid-Cretaceous time, tectonically imbricated, and then subducted after the polarity reversal of the proposed Cretaceous Caribbean Arc.

DE - DESCRIPTORS: Antilles-; Aruba-; blueschist-; Caribbean-region; Central-America; Colombia-; Costa-Rica; Cretaceous-; Curacao-; East-Pacific; exhumation-; Galapagos-Rift; geochemistry-; Greater-Antilles; Hispaniola-; hot-spots; island-arcs; Lesser-Antilles; Mesozoic-; metals-; metamorphic-rocks; metamorphism-; Middle-Cretaceous; Netherlands-Antilles; northern-Venezuela; Pacific-Ocean; paleomagnetism-; plate-tectonics; protoliths-; rare-earths; reversals-; schists-; South-America; subduction-; terranes-; Tobago-; Trinidad-and-Tobago; Venezuela-; Villa-de-Cura-blueschist-belt; West-Indies

CC - CATEGORY CODES: 18-Solid-earth-geophysics; 02C-Geochemistry-of-rocks,-soils,-and-sediments

DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document

BL - BIB LEVEL: Analytic

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute. Reference includes data supplied by the Geological Society of America, Boulder, CO, United States

IS - ISSN: 0016-7592

CO - CODEN: GAAPBC

AN - ACCESSION NUMBER: 2000-030508

UD - UPDATE CODE: 200010

Registro 5303 de 5614 - GeoRef 1997-2001

TI - TITLE: Probabilistic prediction models for landslide hazard mapping.

AU - AUTHORS: Chung-Chang-Jo-F; Fabbri-Andrea-G

AF - AUTHOR AFFILIATION: Geological Survey of Canada, Ottawa, ON, United States

SO - SOURCE: Photogrammetric Engineering and Remote Sensing. 65; 12, Pages 1389-1399. 1999.

PB - PUBLISHER: American Society of Photogrammetry. Falls Church, VA, United States. 1999.

CP - COUNTRY OF PUBLICATION: United-States

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: English

DE - DESCRIPTORS: Bayesian-analysis; cartography-; case-studies; Central-Cordillera; Chincina-Colombia; Colombia-; geographic-information-systems; geologic-hazards; information-systems; landslides-; mass-movements; mathematical-models; prediction-; probability-; South-America; spatial-data; statistical-analysis

CC - CATEGORY CODES: 22-Environmental-geology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

IL - ILLUSTRATION: Refs: 20; illus. incl. 4 tables.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 0099-1112

CO - CODEN: PGMEA9

AN - ACCESSION NUMBER: 2000-026867

UD - UPDATE CODE: 200009

Registro 5304 de 5614 - GeoRef 1997-2001

TI - TITLE: Characterization and origin of obsidians from Colombian and Ecuadorian archaeological sites.

AU - AUTHORS: Bellot-Gurlet-Ludovic; Poupeau-Gerard; Dorighel-Olivier

AF - AUTHOR AFFILIATION: CNRS, Grenoble, France

BK - BOOK TITLE: In: European Union of Geosciences conference abstracts; EUG 10.

BA - BOOK AUTHORS: Anonymous

SO - SOURCE: Journal of Conference Abstracts. 4; 1, Pages 535. 1999.

NT - NOTES: Terra Abstracts, Vol. 11

PB - PUBLISHER: Cambridge Publications. Cambridge, United Kingdom. 1999.

CP - COUNTRY OF PUBLICATION: United-Kingdom

PY - PUBLICATION YEAR: 1999

CN - CONFERENCE INFORMATION: European Union of Geosciences conference; EUG 10. Strasbourg, France. March 28-April 1, 1999.

LA - LANGUAGE: English

DE - DESCRIPTORS: archaeological-sites; archaeology-; artifacts-; Cenozoic-; characterization-; Colombia-; Ecuador-; emission-spectra; experimental-studies; fission-track-dating; geochemistry-; glasses-; igneous-rocks; ICP-mass-spectra; major-elements; mass-spectra; obsidian-; PIXE-spectra; provenance-; Quaternary-; South-America; spectra-; trace-elements; upper-Quaternary; volcanic-rocks; X-ray-spectra

CC - CATEGORY CODES: 24-Quaternary-geology; 03-Geochronology

DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document

BL - BIB LEVEL: Analytic

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 1362-0886

AN - ACCESSION NUMBER: 2000-026620

UD - UPDATE CODE: 200009

Registro 5305 de 5614 - GeoRef 1997-2001

TI - TITLE: La actividad volcanica de Holocene en el Ecuador y Colombia austral; impedimento al desarrollo de las civilizaciones pasadas

Translated Title: Holocene volcanic activity in Ecuador and southern Colombia; constraints for the development of ancient civilizations.

AU - AUTHORS: Hall-Minard-L; Mothes-Patricia-A

AF - AUTHOR AFFILIATION: Escuela Politecnica Nacional, Instituto Geofisico, Quito, Ecuador

BK - BOOK TITLE: In: Actividad volcanica y pueblos Precolombinos en el Ecuador

Translated Title: Volcanic activity and Pre-Columbian towns in Ecuador.

BA - BOOK AUTHORS: Mothes-Patricia-A (convener)

SO - SOURCE: Pages 11-40. 1999.

PB - PUBLISHER: Ediciones Abya-Yala. Quito, Ecuador. 1999.

CP - COUNTRY OF PUBLICATION: Ecuador

PY - PUBLICATION YEAR: 1999

CN - CONFERENCE INFORMATION: 49 congreso internacional de Americanistas ; simposio sobre Actividad volcanica y pueblos Precolombinos en el Ecuador. Quito, Ecuador. July 1997.

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

DE - DESCRIPTORS: agriculture-; Andes-; archaeology-; Cenozoic-; Central-Andes; Central-Cordillera; Colombia-; depositional-environment; Eastern-Cordillera; Ecuador-; eruptions-; geologic-hazards; Holocene-; human-activity; land-use; marker-beds; Northern-Andes; Quaternary-; South-America; tephrochronology-; upper-Holocene; volcanic-ash; volcanic-centers; volcanic-features; volcanism-; volcanoes-; Western-Cordillera

CC - CATEGORY CODES: 24-Quaternary-geology

DT - DOCUMENT TYPE: Book; Conference-Document

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: S013000; N003000; LONG: W0783000; W0793000.

IL - ILLUSTRATION: Refs: 38; illus. incl. 1 table, sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IB - ISBN: 0078-04-440-X

AN - ACCESSION NUMBER: 2000-026510

UD - UPDATE CODE: 200009

Registro 5306 de 5614 - GeoRef 1997-2001

TI - TITLE: Adapting an ecological mangrove model to simulate trajectories in restoration ecology.

AU - AUTHORS: Twilley-Robert-R; Rivera-Monroy-Victor; Chen-Ronghua; Botero-Leonor

AF - AUTHOR AFFILIATION: University of Southwestern Louisiana, Department of Biology, Lafayette, LA, United States

BK - BOOK TITLE: In: Rehabilitation of coastal ecosystems.

BA - BOOK AUTHORS: Edwards-Alasdair (editor); Beveridge-Malcolm (editor); Field-Colin (editor); Fortes-Miguel (editor)

SO - SOURCE: Marine Pollution Bulletin. 37; 8-12, Pages 404-419. 1999.

PB - PUBLISHER: Pergamon. Oxford-New York, International. 1999.

CP - COUNTRY OF PUBLICATION: International

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: English

DE - DESCRIPTORS: Colombia-; concentration-; degradation-; ecology-; ecosystems-; estuarine-environment; forests-; lagoonal-environment; Magdalena-Colombia; mangrove-swamps; mires-; models-; nutrients-; reclamation-; saline-composition; salinity-; Santa-Marta-Colombia; shore-features; simulation-; soils-; South-America; surface-water; swamps-; theoretical-models; tropical-environment; vegetation-; water-quality; wetlands-

CC - CATEGORY CODES: 22-Environmental-geology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N103500; N110100; LONG: W0741600; W0744400.

IL - ILLUSTRATION: Refs: 110; illus. incl. sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 0025-326X

CO - CODEN: MPNBAZ

AN - ACCESSION NUMBER: 2000-025557

UD - UPDATE CODE: 200008

Registro 5307 de 5614 - GeoRef 1997-2001

TI - TITLE: The mangrove ecosystem of the Cienaga Grande de Santa Marta (Colombia); observations on regeneration and trace metals in sediment.

AU - AUTHORS: Perdomo-Laura; Ensminger-Ingo; Espinosa-Luisa-Fernanda; Elster-Carola; Wallner-Kersanach-Monica; Schnetter-Marie-Luise

AF - AUTHOR AFFILIATION: INVEMAR, Santa Maria, Colombia

BK - BOOK TITLE: In: Rehabilitation of coastal ecosystems.

BA - BOOK AUTHORS: Edwards-Alasdair (editor); Beveridge-Malcolm (editor); Field-Colin (editor); Fortes-Miguel (editor)

SO - SOURCE: Marine Pollution Bulletin. 37; 8-12, Pages 393-403. 1999.

PB - PUBLISHER: Pergamon. Oxford-New York, International. 1999.

CP - COUNTRY OF PUBLICATION: International

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: English

DE - DESCRIPTORS: bioavailability-; cadmium-; Colombia-; concentration-; copper-; ecosystems-; environmental-analysis; floods-; fresh-water-environment; heavy-metals; lagoonal-environment; Magdalena-Colombia; Magdalena-River; mangrove-swamps; metals-; mires-; nickel-; protection-; revegetation-; saline-composition; Santa-Marta-Colombia; sediments-; shore-features; South-America; surface-water; swamps-; trace-metals; vegetation-; zinc-

CC - CATEGORY CODES: 22-Environmental-geology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N103500; N110100; LONG: W0741100; W0741600.

IL - ILLUSTRATION: Refs: 41; illus. incl. 4 tables, sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute.

IS - ISSN: 0025-326X

CO - CODEN: MPNBAZ

AN - ACCESSION NUMBER: 2000-025556

UD - UPDATE CODE: 200008

Registro 5308 de 5614 - GeoRef 1997-2001

TI - TITLE: Sedimentology and sequence stratigraphy of the Caballos Formation, San Francisco Field, upper Magdalena Valley.

AU - AUTHORS: Ramon-Juan-Carlos; Pavas-Jaime

AF - AUTHOR AFFILIATION: HOCOL, Bogota, Colombia

BK - BOOK TITLE: In: American Association of Petroleum Geologists 1999 annual meeting.

BA - BOOK AUTHORS: Anonymous

SO - SOURCE: Annual Meeting Expanded Abstracts - American Association of Petroleum Geologists. 1999; Pages A113-A114. 1999.

PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 1999.

CP - COUNTRY OF PUBLICATION: United-States

PY - PUBLICATION YEAR: 1999

CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 1999 annual meeting. San Antonio, TX, United States. Apr. 11-14, 1999.

LA - LANGUAGE: English

AB - ABSTRACT: Sedimentological and stratigraphical interpretation of 92 well logs calibrated with about 1070 feet of cored section, and 25 FMI logs allows a detail reconstruction of the sedimentary environments and the stratigraphic evolution during Aptian-Albian time. The lower Caballos member consists of stacked fluvial and crevasse-splay sandstones locally intercalated with floodplain mudstones and siltstones. Stacking pattern of successive stratigraphic cycles shows onlap over a high relief paleo-topography. A local baselevel fall toward the top of the Lower Caballos resulted in amalgamated blanket sandstones. Progressive increase in base-level resulted in deposition of swamp mudstones that are covered by open bay mudstones and fossiliferous marls. These middle unit mudstones pass transitionally to inner bay and coastal plain mudstones and siltstones. Locally fluvial sandstone bodies occur toward the top of this middle Caballos member. This transition records the bay fill as the base-level falls. A relative rise in sea level resulted in flooding of paleo-valleys and deposition of an heterolithic mix of sandstones and mudstones. Random alternation of through and planar cross-bedded, medium sandstones with ripple-laminated, finer sandstones indicate variable energy conditions. Lack of intraclasts at the base of thick ripple laminated sandstones indicate non-erosive contacts. Massive sandstones change laterally to gray mudstones with hematite-cemented "layers" deposited under brackish conditions. The progressive rise in sea level causes the flooding of the estuary. Open marine glauconite- and fossil-rich mudstones cover estuarine deposits.

DE - DESCRIPTORS: Albian-; Aptian-; bedding-plane-irregularities; brackish-water-environment; Caballos-Formation; calibration-; clastic-rocks; Colombia-; cores-; Cretaceous-; cross-bedding; cycles-; depositional-environment; estuarine-environment; fluvial-environment; laminations-; Lower-Cretaceous; Magdalena-Valley; marl-; Mesozoic-; mudstone-; oil-and-gas-fields; petroleum-; planar-bedding-structures; reconstruction-; ripple-marks; San-Francisco-Field; sandstone-; sea-level-changes; sedimentary-rocks; sedimentary-structures; sequence-stratigraphy; South-America; transgression-; well-logs

CC - CATEGORY CODES: 29A-Economic-geology,-geology-of-energy-sources; 12-Stratigraphy

DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document

BL - BIB LEVEL: Analytic

RF - REFERENCE SOURCE: GeoRef, Copyright 2002, American Geological Institute. Reference includes data supplied by American Association of Petroleum Geologists, Tulsa, OK, United States

IS - ISSN: 0094-0038

CO - CODEN: APGAB2

AN - ACCESSION NUMBER: 2000-018140

UD - UPDATE CODE: 200006

Registro 5309 de 5614 - GeoRef 1997-2001

TI - TITLE: Three-dimensional structure of the Girardot Belt; a sample of the structure of the Cordillera Oriental, Colombia.

AU - AUTHORS: Montes-Camilo; Hatcher-Robert-D Jr.

AF - AUTHOR AFFILIATION: University of Tennessee, Knoxville, TN, United States

BK - BOOK TITLE: In: American Association of Petroleum Geologists 1999 annual meeting.

BA - BOOK AUTHORS: Anonymous

SO - SOURCE: Annual Meeting Expanded Abstracts - American Association of Petroleum Geologists. 1999; Pages A94-A95. 1999.

PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 1999.

CP - COUNTRY OF PUBLICATION: United-States

PY - PUBLICATION YEAR: 1999

CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 1999 annual meeting. San Antonio, TX, United States. Apr. 11-14, 1999.

LA - LANGUAGE: English

AB - ABSTRACT: The three-dimensional structure and deformation of a segment of the Cordillera Oriental of Colombia is analyzed using detailed geologic mapping, strain analysis, subsurface information, and remote sensing. The Girardot belt, a complex area along the western flank of the Cordillera Oriental, shares structural and stratigraphic features with the Upper Magdalena Valley and the Cordillera Central. This deformed belt contains faults that further north are thought to accommodate much of the northwestward displacement of the Cordillera Oriental, as well as large dextral strike-slip faults from the Cordillera Central. In addition, this belt is the only place where Jurassic intrusive bodies (not basement) belonging to the Cordillera Central domain are present in the western foothills of the Cordillera Oriental. This unique overlap facilitates the study of the relationship (both in space an time) between a strike-slip dominated orogen (Cordillera Central), and a thrust dominated one (Cordillera Oriental). Also, syntectonic deposits and neotectonic features allow to accurately date the relative timing of events. The study of three dimensional deformation and structural geometry in the Cordillera Oriental will help solve the inconsistency that exists between regional balanced cross-sections, and tectonic models of the Caribbean. Balanced cross-sections assume that no deformation has taken place along the strike; about 100 km of NW-SE horizontal shortening has been estimated invoking a doubly vergent fold-thrust geometry. This implies that deformation paths are perpendicular to the trend of the Cordillera (NW-SE dip-slip). On the other hand, kinematic plate tectonic reconstructions predict that the Cordillera Oriental of Colombia experienced oblique convergence throughout the Cenozoic as a result of its location between the Caribbean and South American plates. This contradiction may introduce significant errors and distortions in estimates of horizontal shortening, hydrocarbon maturation and migration histories, and basin reconstructions.


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