No. Registros Solicitud 1 5614 colombia



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IL - ILLUSTRATION: Refs: 7; illus. incl. 1 table, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027130

UD - UPDATE CODE: 200309

Registro 394 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Caracteristicas mineralogicas e inclusiones fluidas de las Esmeraldas del Municipio de San Antonio de Yacopi, Cundinamarca, Colombia

Translated Title: Mineralogical characteristics and fluid inclusions of the San Antonio de Yacopi emeralds, Cundinamarca, Colombia.

AU - AUTHORS: Romero-Ordonez-Fernando-H-H; Hernandez-Pardo-Orlando

AF - AUTHOR AFFILIATION: Universidad Nacional de Colombia, Departamento de Geociencias, Bogota, Colombia

SO - SOURCE: Geologia Colombiana. 24; Pages 149-158. 1999.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: The San Antonio de Yacopi emerald district is located in the western emerald belt of the Cordillera Oriental, in the Vasquez-Yacopi territory. The emerald mineralization of this district are found in lower cretaceous marine sedimentary rocks belonging to the stratigraphical unit recognized as La Palma Group. The emplacement characteristics of the mineralizations of the area suggest a tectonic control associated with regional and minor faults that are affecting the sedimentary sequence. The emeralds are found in veins, lenses and nodular deposits frequently associated with calcite veins, breccias, black shales and calcareous rocks. The aim of this study is to extent the knowledge about the characteristics of the mineralizations and the analysis of the formation environment of the San Antonio de Yacopi emerald deposits. A mineralogical study was carried out, describing physical properties, such as refraction indexes of some emerald crystals and microthermometric properties of the fluid inclusion emerald crystals allowing the definition of thermobarometric conditions on the formation environment of the emerald deposits. Based on these studies it is possible to conclude that there are not remarkable differences in the cell parameters among the San Antonio, Coscuez, Muzo and Chivor emerald districts. The microthermometric data show that the temperatures of the formation are in the range from 300 degrees C, to 350 degrees C, being normal in the general context of the western emerald belt. The eutectic temperatures are low, indicating the presence of a complex mixture of dissolved ions in the aqueous phase, including K (super +) , Ca (super ++) , Cl (super -) , Fe (super +3) , Mg (super ++) , Al (super +3) . The thermobarometric measurements indicate a range of values from 900 to 1000 bars, suggesting that the emerald deposits were formed at shallow crust levels, at approximately 800 m below the surface, closely associated with similar depths of formation assigned to other emerald localities including Muzo, Pacho, Coscuez and Chivor emerald districts. These deposits were formed from a unique mineralized fluid, being the small differences in composition attached to slightly local changes, related to local processes that were occurring at the moment of the emerald crystal formation.

DE - DESCRIPTORS: Andes-; black-shale; breccia-; Buenvista-Mine; calcite-; carbonate-rocks; carbonates-; Chivor-Colombia; clastic-rocks; Colombia-; Coscuez-Colombia; Cretaceous-; Cundinamarca-Colombia; Eastern-Cordillera; El-Eden-Mine; emerald-; fluid-inclusions; gems-; Guadualito-Mine; inclusions-; La-Glorieta-Mine; La-Palma-Group; limestone-; marine-sediments; Mesozoic-; Muzo-Colombia; Pacho-Colombia; physical-properties; pressure-; ring-silicates; San-Antonio-de-Yacopi-Colombia; sedimentary-rocks; sediments-; silicates-; South-America; Tapias-Mine; tectonic-breccia; temperature-; thermochemical-properties; thermomechanical-properties; veins-

CC - CATEGORY CODES: 01C-Mineralogy-of-non-silicates

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N043000; N053000; LONG: W0733000; W0743000.

IL - ILLUSTRATION: Refs: 23; illus. incl. 2 plates, 4 tables, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027129

UD - UPDATE CODE: 200309

Registro 395 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: La sucesion paleoambiental del Cretacico de la region de Tequendama y oeste de la Sabana de Bogota, Cordillera Oriental Colombiana

Translated Title: Cretaceous paleoenvironmental succession in the Tequendama and western Sabana de Bogota regions, Eastern Cordillera, Colombia.

AU - AUTHORS: Martinez-R-Jose-Ignacio; Vergara-S-Luis-Eduardo

AF - AUTHOR AFFILIATION: Universidad EAFIT, Departamento de Geologia, Medellin, Colombia

SO - SOURCE: Geologia Colombiana. 24; Pages 107-147. 1999.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: A stratigraphic, micropaleontologic and petrographic survey of ca. 4000 m of the Cretaceous Villeta, Guadalupe and Olini Groups and the Lomagorda Formation outcropping in the Tequendama and west of Bogota regions, is presented. Two facial settings are recognized, and apparently controlled at times, by the Bituima Fault. East of the Bituima Fault, at least six stratigraphic sequences can be interpreted beginning with the late Barremian calcareous-siliceous rocks of the Trincheras Formation and ending with the regressive arenites of the Labor and Tierna Formations. A clastic-evaporitic (?) phase is suggested for the late Aptian-early Albian (Socota and lower Capotes Formations) implying tectonic restriction of the basin and a deep-water setting. Anoxia at the sediment-water interface is inferred for intervals at the early Aptian (Trincheras Formation), the late Aptian-early Cenomanian (Socota, Capotes and Hilo Formations), the Turonian-Coniacian (La Frontera and Conejo Formations), and the late Campanian (the Plaeners Formation). West of the Bituima Fault, at least two sequences can be interpreted, beginning with the Coniacian Lomagorda Formation and ending with the regressive Maastrichtian Nivel de Lutitas y Arenas. These distal, offshore facies were strongly influenced by upwelling (and anoxia) during the Coniacian-Santonian (Lidita Inferior Formation) and Campanian (Lidita Superior Formation) intervals. A correlation between both stratigraphic settings is attempted.

DE - DESCRIPTORS: Ammonoidea-; Andes-; Arthropoda-; biostratigraphy-; Bivalvia-; Bryozoa-; Cephalopoda-; Chordata-; Cirripedia-; Colombia-; Cretaceous-; Crustacea-; Dinoflagellata-; dropstone-; Eastern-Cordillera; Echinodermata-; Echinoidea-; Echinozoa-; facies-; Foraminifera-; fossil-wood; Gastropoda-; Invertebrata-; lithostratigraphy-; Mandibulata-; Mesozoic-; microfossils-; Mollusca-; nomenclature-; Ostracoda-; paleoecology-; paleoenvironment-; paleogeography-; palynomorphs-; Pisces-; Polychaetia-; Protista-; Radiolaria-; Sabana-de-Bogota; sedimentary-rocks; sequence-stratigraphy; Serpulidae-; South-America; succession-; taxonomy-; Tequendama-Colombia; Tetrabranchiata-; Vermes-; Vertebrata-

CC - CATEGORY CODES: 12-Stratigraphy

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N044000; N050500; LONG: W0740500; W0743000.

IL - ILLUSTRATION: Refs: 92; illus. incl. strat. cols., 6 plates, 1 table, sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027128

UD - UPDATE CODE: 200309

Registro 396 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Mariliasuchus; um novo Crocodylomorpha (Notosuchia) do Cretaceo da Bacia Bauru, Brasil

Translated Title: Mariliasuchus; a new Crocodylomorpha (Notosuchia) from the Cretaceous of the Bauru Basin, Brazil.

AU - AUTHORS: Souza-Carvalho-Ismar; Bertini-Reinaldo-Jose

AF - AUTHOR AFFILIATION: Universidade Federal do Rio de Janeiro, Instituto de Geociencias, Rio de Janeiro, Brazil

SO - SOURCE: Geologia Colombiana. 24; Pages 83-105. 1999.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Portuguese

LS - LANGUAGE OF SUMMARY: English; Spanish

AB - ABSTRACT: The notosuchians are a peculiar crocodylomorph group, that show a wide distribution in Cretaceous rocks from South America and Africa. They belong to the characteristic Gondwana terrestrial biota. These crocodylians of small size were terrestrial and probably omnivorous. Their morphological aspects allow to associate them to the most primitive members of this order. In the Bauru Basin, at Marilia County (Sao Paulo, Brazil), it was found in Adamantina/Aracatuba Formation (Bauru Group-?Coniacian) a new species of the Notosuchia infraorder. It was named as Mariliasuchus amarali, and its morphology allow the analyses of the relationships among the notosuchians from the northern and southern regions of South America. Besides it is possible some new paleoecological and chronostratigraphic interpretations to Bauru Basin. Mariliasuchus amarali is a notosuchian of Notosuchidae family that presents a small skull with a short rostrum. The premaxilla-maxilla contact is vertically oriented presenting an indentation. The orbits are large and they are located on the middle area of the skull. The supratemporal fenestrae are small and circular. The external nares are anterolaterally oriented without internarial bar. In the premaxilla there are two smaller anterior conical teeth, and a third large caniniform tooth. The maxilla has three molariform teeth whose roots are separated from the crown by a constriction. These teeth show a bulbous crown shape. They decrease in size backwards. They are limited to the first half of the maxilla. The general morphology of Mariliasuchus is similar to Notosuchus, although are clearly distinct by the skull size, the supratemporal fenestrae shape, the mandibular fenestra and the teeth distribution on the premaxilla and maxilla.

DE - DESCRIPTORS: Adamantina-Formation; Aracatuba-Formation; Archosauria-; argillite-; Bauru-Basin; Bauru-Group; biostratigraphy-; Brazil-; Chordata-; clastic-rocks; Coniacian-; correlation-; Cretaceous-; Crocodilia-; Crocodylomorpha-; Diapsida-; Gondwana-; Marilia-Brazil; Mariliasuchus-; Mesozoic-; new-taxa; Notosuchia-; paleoecology-; Parana-Basin; Reptilia-; Rio-do-Peixe-River; sandstone-; Sao-Paulo-Brazil; sedimentary-rocks; Senonian-; siltstone-; South-America; taxonomy-; Tetrapoda-; Upper-Cretaceous; Vertebrata-

CC - CATEGORY CODES: 11-Vertebrate-paleontology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: S223000; S220000; LONG: W0493000; W0500000.

IL - ILLUSTRATION: Refs: 39; illus. incl. 2 plates, geol. sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027127

UD - UPDATE CODE: 200309

Registro 397 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Comparacion de los estilos estructurales en la seccion entre Bogota y los Farallones de Medina, Cordillera Oriental de Colombia

Translated Title: Comparison of structural styles in the Bogota to Farallones de Medina transect, Eastern Cordillera, Colombia.

AU - AUTHORS: Mora-Andres; Kammer-Andreas

AF - AUTHOR AFFILIATION: Universidad Nacional de Colombia, Departamento de Geociencias, Bogota, Colombia

SO - SOURCE: Geologia Colombiana. 24; Pages 55-82. 1999.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: Between the Bogota area and the Farallones range there is a marked contrast between two structural styles of an opposed vergence. To the east, a distinct marginal high, referred to as Chingaza dome, displays by its asymmetry and its faulted eastern flank an eastern vergence. Open second-order folds, associated to an axial plane cleavage, affect this dome. Ptygmatitic folds yield local shortening values of 40% along this structural high, but decrease notably toward the adjacent structural depressions. Deformation affects both basement and cover rocks and precludes, by its homogeneous nature, a detachment within the lower Cretaceous shales. On the western extreme of our study region, the anticlines around the Teusaca River display significant amplitudes and steeply inclined to inverted western flanks. Folding occurred by flexural slip and a layer parallel strain is here completely absent. The line-length balancing of these frontal folds yields shortening values of 17%. The geometric properties of these folds require two detachment horizons. Between these two opposed areas, the Rio Blanco region is affected by an intermediate structural style. Folding of the frontal parts of this fold belt is viewed as a consequence of an uplift and a homogeneous shortening of the Chingaza dome, which prompted a partial detachment of the Cretaceous cover and its gravity-driven displacement toward the structural depression of the Savannah of Bogota.

DE - DESCRIPTORS: Andes-; basement-; Bogota-Colombia; Cenozoic-; Chingaza-Dome; cleavage-; Colombia-; Cretaceous-; crustal-shortening; deformation-; Eastern-Cordillera; Farallones-de-Medina-Colombia; folds-; foliation-; gravity-sliding; Jurassic-; Mesozoic-; Quetame-Massif; Rio-Blanco-Colombia; San-Juanito-Fault; South-America; structural-analysis; style-; tectonics-; Tertiary-; Teusaca-River; uplifts-

CC - CATEGORY CODES: 16-Structural-geology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N040500; N042500; LONG: W0734000; W0740000.

IL - ILLUSTRATION: Refs: 35; illus. incl. sects., strat. cols., 4 tables, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027126

UD - UPDATE CODE: 200309

Registro 398 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Observaciones acerca de un origin transpresivo de la Cordillera Oriental

Translated Title: The transpressive origin of the Eastern Cordillera.

AU - AUTHORS: Kammer-Andreas

AF - AUTHOR AFFILIATION: Universidad Nacional de Colombia, Departamento de Geociencias, Bogota, Colombia

SO - SOURCE: Geologia Colombiana. 24; Pages 29-53. 1999.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: In this paper we consider characteristic relay patterns of marginal folds at both borders of the Eastern Cordillera and confront them with a regional compilation of fault-slip data and a preliminary evaluation of joint sets. Complementary deformation patterns of right-stepped fold pairs along NW-trending borders and left stepped structural relays along a N-S trending deformation front comply to a transpressional deformation with a constrictional strain direction of about 300 degrees . Fault/slickenside pairs pertain mostly to strike-slip deformations and their populations define, to a first approximation, pseudoconjugate sets, whose compression or extension directions are emphasised further by reverse or normal fault pairs. In the Santander Massif the compression or extension directions are oriented both perpendicularly to the NNE striking Bucaramanga fault and to N-S trending, faulted sedimentary layers of the Massif's internal parts. To the W of the Bucaramanga fault, and affecting most of the Bogota segment, the striated faults record a consistent clockwise departure from the perpendicular to the structural trend, reflecting probably a late incremental strain. In contrast, joints evidence a pre-folding origin and document shortening directions, which support the constrictional bearing derived from the regional analysis. With this initial constellation of a homogeneous far stress field, the model of a simple transpression applies for the folding of the Bogota segment. In the Santander Massif, this simple transpression is likely to be partitioned into a strike-slip deformation along the Bucaramanga fault at its western border fault and a homogeneous pure shear in the remaining massif. This first appreciation may, however, be modified, considering the presence of a preferred simple shear along sinistral fault planes, which occupy the position of Riedel shears with respect to the Bucaramanga fault, so that some strike-slip deformation may be distributed across the whole massif.

DE - DESCRIPTORS: Andes-; Bucaramanga-Fault; Colombia-; compression-tectonics; deformation-; Eastern-Cordillera; faults-; folds-; forelands-; fractures-; joints-; lateral-faults; left-lateral-faults; normal-faults; reverse-faults; Santander-Massif; shear-; South-America; stereographic-projection; strike-slip-faults; structural-analysis; style-; tectonics-; transpression-

CC - CATEGORY CODES: 16-Structural-geology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N050000; N070000; LONG: W0720000; W0740000.

NN - ANNOTATION: Includes appendices.

IL - ILLUSTRATION: Refs: 35; illus. incl. 2 tables, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027125

UD - UPDATE CODE: 200309

Registro 399 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: La Cordillera Oriental Colombiana no se desprende de la Cordillera Central

Translated Title: The link between the Eastern and Central Cordilleras of Colombia.

AU - AUTHORS: Ujueta-Guillermo

AF - AUTHOR AFFILIATION: Universidad Nacional de Colombia, Departamento de Geociencias, Bogota, Colombia

SO - SOURCE: Geologia Colombiana. 24; Pages 3-28. 1999.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1999.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1999

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: Geologically the Central and Eastern Cordilleras depict different periods of genesis and different types of rocks which allow them to keep their identities and independence from Colombia to Bolivia; however, in the area of study are connected by a bridge formed by a recent geomorphological feature which is the result of combined tectonic and volcanic stresses which took place toward the end of the Pliocene. This bridge has a direction NW-SE and connects the Cutanga Volcano on the Central Cordillera with the Highs of La Fragua on the Eastern Cordillera and is recognized as Serrania de La Fragua. This Serrania of La Fragua has been poorly examined in the geographic sense, and ignored geologically. In order to justify its presence, two hypothesis are presented, where mainly deep fracturing, plus uplifting and subordinately the emission of ignimbrites or basaltic lava flows along the aligned volcanic centres developed on the fracture systems. These lava flows formed a high plain which is presently dissected and diminished. According with known data the high plain is preferentially formed by ignimbrites. The preservation of this high plain between 2.700 and 3.000 meters above sea level as a result of a relative resistance to the erosion, is the main cause of the bridge between the Central and Eastern Cordilleras which for more than 100 years has suggested the bifurcation of the two cordilleras. Unfortunately this idea is erroneous, but has been accepted in Colombia and also in foreign countries. The Tectonic Depression of the Upper Magdalena Valley (VSM) is a continuous feature that virtually disappears close to Mocoa, at the Guairapungo lineament; however it could continue all the way to Ecuador as a very narrow strip. This depression has a general strike NNE-SSW and possibly was initially uninterrupted all the way. It has been divided in several sub-basins due to differential movements of deep old faults, with general strikes NW-SE, which have been named Lineaments. In the area the Lineaments of Guairapungo, La Fragua, Purace and Suarez are identified. The knowledge related to the last Andean paroxysm and the relationship with volcanic activity is reduced. The lineaments previously mentioned have been reactivated in the last stages of the andean orogeny, mainly connected with basaltic emissions, as well as geoformes formed by rhyolitic and dacitic events. The stratigraphic relationship between the different geologic units have not been well defined. It is urgent to conduct a well detailed stratigraphic analysis of the mountain area, known as Caqueta High Basin, which has been considered as part of the Putumayo Basin.

DE - DESCRIPTORS: Altiplano-; Andes-; basalts-; basins-; Central-Cordillera; Colombia-; Eastern-Cordillera; faults-; fissures-; igneous-rocks; ignimbrite-; intermontane-basins; lithostratigraphy-; metamorphic-rocks; metasedimentary-rocks; Phanerozoic-; Precambrian-; pyroclastics-; South-America; stratigraphic-units; volcanic-rocks

CC - CATEGORY CODES: 16-Structural-geology; 12-Stratigraphy

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N010000; N030000; LONG: W0750000; W0770000.

IL - ILLUSTRATION: Refs: 56; illus. incl. 2 plates, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute.

IS - ISSN: 0072-0992

CO - CODEN: GECBA7

AN - ACCESSION NUMBER: 2003-027124

UD - UPDATE CODE: 200309

Registro 400 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Geoformas asociadas al Batolito Antioqueno

Translated Title: Landforms associated with the Antioquian Batholith.

AU - AUTHORS: Londono-G-Ana-Cristina

AF - AUTHOR AFFILIATION: Ingeominas, Medellin, Colombia

SO - SOURCE: Geologia Colombiana. 23; Pages 133-143. 1998.

PB - PUBLISHER: Universidad Nacional de Colombia, Facultad de Ciencias, Departamento de Geociencias. Bogota, Colombia. 1998.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 1998

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: The Antioquian Batholith is the biggest plutonic body in the Central Cordillera of Colombia. It intrudes all the surrounding rocks, and differs from other plutonic bodies from orogenic chains by its lithological homogeneity and low petrochemical variations; its most important facies are the granodioritetonalite series: massive, phaneritic, equigranular and medium grained rocks. The humid equatorial climate of Colombian Andes favors chemical weathering of the Antioquian Batholith, and has produced a thick saprolith cover. The trapezoid shape of the Antioquian Batholith and the deformation associated with its emplacement have not been entirely explained yet; on the eastern edge shear zones occur where weathering and erosion processes take place and accelerate the development of particular geoforms such as quartz blocks and tabular forms. The geoforms are the result of geological processes and the climatic conditions that had affected the batholith since it reached the surface. The morphologic evolution depends on several phenomena such as chemical weathering, and the transport and erosive agents that modify the landscape. Characteristic geoforms developed on the Antioquian Batholith are: "penoles", boulders, "organales", "acanaladuras", quartz lines, tabular forms and pseudokarst, and several erosion surfaces generated by the uplift of the Central Cordillera and separated by deep valleys.


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