No. Registros Solicitud 1 5614 colombia

DE - DESCRIPTORS: Andean-Orogeny; Andes-; Basin-and-Range-Province; California-; Cenozoic-; Central-Valley; Chile-; Coast-Ranges; Colombia-; continental-crust; crust-; deformation-; faults-; Franciscan-Complex; geotraverses-; intrusions-; island-arcs; Laramide-Orogeny; magmatism-; Mesozoic-; models-; Nevada-; North-America; North-American-Cordillera; ophiolite-complexes; orogeny-; Pacific-Plate; paleoenvironment-; paleogeography-; Peru-; plate-collision; plate-tectonics; Rocky-Mountains; San-Andreas-Fault; sedimentation-; Sierra-Nevada-Batholith; South-America; stratigraphic-units; subduction-zones; tectonics-; tectonostratigraphic-units; terranes-; Tertiary-; U.-S.-Rocky-Mountains; United-States; volcanism-

CC - CATEGORY CODES: 18-Solid-earth-geophysics

DT - DOCUMENT TYPE: Serial; Conference-Document

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N310000; N390000; LONG: W1140000; W1220000.

IL - ILLUSTRATION: Refs: 94; illus. incl. geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IB - ISBN: 0-9665869-6-4

CO - CODEN: #05426

AN - ACCESSION NUMBER: 2004-041390

UD - UPDATE CODE: 200412

Registro 111 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Comparative fluid inclusion studies of the San Martin Skarn (Mexico) and the epithermal Comstock Lode (USA) and Pachuca-Real del Monte (Mexico) Deposits.

AU - AUTHORS: Campos-Alvarez-N-O

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 117-126. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: English

LS - LANGUAGE OF SUMMARY: Spanish

AB - ABSTRACT: The San Martin (Mexico), Pachuca-Real del Monte (Mexico) and Comstock Lode (USA) are base-metal and silver deposits within Cretaceous to Tertiary volcano-sedimentary host rocks. The first is a skarn type deposit whilst the second and third are epithermal vein-type deposits. A fluid inclusion study of quartz, sphalerite and fluorite was undertaken to characterize mineralizing solutions which have different compositions and temperatures. Microthermometric measurements were made based on the recognition of changes of two-phase liquid-rich, two-phase vapor-rich and multiphase (NaCl) inclusions during heating and freezing experiments. Homogenization temperatures and salinities of fluid inclusions in quartz and fluorite from San Martin range from 300 to 320 degrees C and 5.0 to 40 eq. wt. % NaCl based on Tm (sub Ice) and T (sub NaCl) . Halite as a daughter mineral is often present in quartz and fluorite. However in the other districts, the Th and salinity values in sphalerite (Pachuca-Real) and quartz (Comstock) are lower: 265 degrees C and 3.4% eq. wt. NaCl and 251 degrees C and 0.3 eq. wt. % NaCl respectively. Data from a single zoned quartz crystal provides evidence of fluid evolution at the Comstock Lode. Temperatures and salinities observed were 249 degrees C and 0.6 eq wt % NaCl at the core and 245 degrees C and 0.1 eq wt % NaCl at the rim. The salinity and temperature of the hydrothermal brines seems to be an important factor in explaining the precipitation of the ore minerals. These deposits are characterized by temperatures <350 degrees C and salinities from 0.2 to 4.93 wt % eq. NaCl. Estimated pressures and depths range from 41 to 103 bars and 472 to 1394 meters.

DE - DESCRIPTORS: Cenozoic-; chemical-composition; Comstock-Lode; controls-; Cretaceous-; deformation-; depth-; epithermal-processes; faults-; fluid-inclusions; fluid-phase; geochemistry-; geologic-barometry; geologic-thermometry; granites-; Hidalgo-Mexico; igneous-rocks; inclusions-; Mesozoic-; metal-ores; metallogeny-; metamorphic-rocks; metasomatic-rocks; Mexico-; mineral-assemblages; mineral-composition; mineral-deposits,-genesis; mineral-exploration; Nevada-; Pachuca-Real-del-Monte-mining-district; petrography-; plutonic-rocks; pressure-; quartz-monzonite; Reno-Nevada; salinity-; San-Martin-mining-district; sedimentary-rocks; silver-ores; skarn-; stratigraphic-units; temperature-; Tertiary-; United-States; volcanic-rocks; Washoe-County-Nevada; Zacatecas-Mexico; zinc-ores

CC - CATEGORY CODES: 27A-Economic-geology,-geology-of-ore-deposits; 05A-Igneous-and-metamorphic-petrology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N390700; N420000; LONG: W1191000; W1200000.

LAT: N194500; N203000; LONG: W0983000; W0993000.

LAT: N213000; N230000; LONG: W1020000; W1040000.

IL - ILLUSTRATION: Refs: 22; illus. incl. 1 plate, 1 table, sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041188

UD - UPDATE CODE: 200412

Registro 112 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Mineralogia, geoquimica y algunos aspectos geneticos de la mina El Diamante; Narino, Colombia

Translated Title: Mineralogy, geochemistry and some genetic aspects of El Diamante Mine; Narino, Colombia.

AU - AUTHORS: Molano-Juan-C; Shimazaki-H

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

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 105-116. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: The Diamante mine is located in the southwestern part of Colombia on the west flank of the Occidental Andes Cordillera. The fluid associated with gold mineralization has a range of salinity between 1.7 to 5.8 wt % NaCl equivalent. Densities vary from 0.58 to 0.92 g/cc. Homogenization temperature averages range between 228-340 degrees C. delta (super 34) S (sub pyrite) values of -7.1 to -5.3 per mil and delta (super 34) S (sub ss) = -5.7 per mil suggest a mixing of sulfur with sedimentary and magmatic origin. The delta (super 18) O and dD values for the fluids are 7.6 to 9.6 per mil and -74 to -83 per mil, respectively. The isotopic and fluid inclusion data of ore fluids suggest that the gold mineralization at the Diamante mine may have evolved from mixing of magmatic and meteoric fluids possibly related to intrusion of the nearby Piedrancha Granodiorite of late Miocene age. The gold deposition is attributed to destabilization of the bisulfide complex as a result of decrease of the sulfur activity, through sulfide deposition and/or H (sub 2) S loss.

DE - DESCRIPTORS: Cenozoic-; chemical-composition; Colombia-; Dagua-Group; El-Diamante-Mine; fluid-inclusions; fluid-phase; geochemistry-; gold-ores; ground-water; Guachavez-Colombia; hydrogen-sulfide; hydrothermal-alteration; igneous-rocks; inclusions-; intrusions-; isotope-ratios; isotopes-; Mesozoic-; metal-ores; metallogeny-; metasomatism-; meteoric-water; mineral-assemblages; mineral-composition; mineral-deposits,-genesis; mineral-exploration; mineralization-; mines-; Miocene-; Narino-Colombia; Neogene-; O-18-O-16; oxygen-; paragenesis-; petrography-; Piedrancha-Stock; quartz-veins; S-34-S-32; salinity-; sedimentary-rocks; SEM-data; South-America; stable-isotopes; stocks-; stratigraphic-units; sulfur-; temperature-; Tertiary-; upper-Miocene; veins-; volcanic-rocks

CC - CATEGORY CODES: 27A-Economic-geology,-geology-of-ore-deposits; 02C-Geochemistry-of-rocks,-soils,-and-sediments

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N010000; N023000; LONG: W0770000; W0783000.

IL - ILLUSTRATION: Refs: 48; illus. incl. 2 tables, sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041187

UD - UPDATE CODE: 200412

Registro 113 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Los Delirios; un yacimiento hidrotermal de oro y plata en la region de Vetas, Santander, Colombia

Translated Title: Los Delirios, a hydrothermal Au-Ag deposit in Vetas, Santander, Colombia.

AU - AUTHORS: Garcia-Ramirez-C-A; Uribe-Portilla-E

AF - AUTHOR AFFILIATION: Universidad Industrial de Santander, Escuela de Geologia, Bucaramanga, Colombia

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 91-103. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: Los Delirios Au-Ag deposits is located 700 meters northwestern of Vetas city (Departamento de Santander) and consists of quartz-sulfide-oxides veins that cuts quartz-feldspar bearing biotite gneisses from Bucaramanga Gneiss Formation. Three vein systems are determined: (1) N30-45 degrees W dips 25-40 degrees NW; (2) N10 degrees W dips 60-70 degrees SW; (3) N70 degrees W dips 70 degrees SW or 60 degrees NE. The vein thickness is between 0.45 and 2.0 meters. The veins have a gray color and massive to brecciated and cavernous structures. The ore mineralogy consists in gold, silver, pyrite, chalcopyrite, pyrrhotite, galena, bornite, calcosine, marcasite, covelline, tetrahedrite, ilmenite, magnetite, hematite. Gange minerals are mainly quartz and plagioclase. The alteration of the deposits is phyllic. The gold and silver contents are 0.5-2.0 gr/T y 0.0-6.48 gr/T respectively. Ore mineralogy, wall alteration and dominant Au-Ag-Pb mineralization in the deposits are like epithermal low-sulfidation or adularia-sericite systems.

DE - DESCRIPTORS: alteration-; chemical-analysis; chemical-composition; Colombia-; dip-; epithermal-processes; facies-; faults-; folds-; foliation-; gangue-; geochemistry-; gold-ores; granites-; granodiorites-; hydrothermal-alteration; igneous-rocks; intrusions-; Los-Delirios-Deposit; mapping-; Mesozoic-; metal-ores; metallogeny-; metamorphic-rocks; metasomatism-; microscope-methods; mineral-assemblages; mineral-composition; mineral-deposits,-genesis; mineral-exploration; Neis-de-Bucaramanga-Formation; Paleozoic-; paragenesis-; plutonic-rocks; quartz-veins; Santander-Colombia; Santander-Massif; Silgara-Formation; silver-ores; South-America; stratigraphic-units; stratigraphy-; strike-; structural-controls; sulfur-; systems-; veins-; Vetas-Colombia; X-ray-diffraction-data

CC - CATEGORY CODES: 27A-Economic-geology,-geology-of-ore-deposits

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N074500; N081500; LONG: W0723000; W0733000.

IL - ILLUSTRATION: Refs: 15; 2 plates, 3 tables, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041186

UD - UPDATE CODE: 200412

Registro 114 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Nuevas evidencias acerca de la presencia de una banda de cizallamiento en la secuencia metapelitica de la formacion Silgara, sector Aratoca-Pescadero; region suroccidental del macizo de Santander

Translated Title: New evidence for a shear zone within the metapelitic sequence of the Silgara Formation, Aratoca-Pescadero area, southwestern Santander Massif, Colombia.

AU - AUTHORS: Mantilla-Figueroa-L-C; Rios-Reyes-C-A; Gelvez-Llanes-J-R; Marquez-Romero-R-E; Ordonez-Calderon-J-C; Cepeda-Espitia-S

AF - AUTHOR AFFILIATION: Universidad Industrial de Santander, Escuela de Geologia, Bucaramanga, Colombia

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 81-89. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: The metamorphic sequence of the Silgara Formation that crops out in Pescadero-Aratoca area (southwestern region of the Santander Massif), presents evidences of having suffered an important shear deformation during its exhumation path, which affected great part of the metamorphic rocks from the garnet and staurolite-kyanite zones. This ductile deformation of extensional character generated structures such as lineations, pressure shades, mylonitization zones, isoclinal recumbent folds, rootless folds, boudins, as well as the elongation of garnet crystals and the truncation of their chemical zonation, which suggest a process of gravitational collapse with an East motion, that affected the Caledonian paleo-orogen. These deformational elements, along with the evidences of an important circulation of hydrothermal fluids, make this region of the Santander Massif an important place to pay attention to explore mesothermal deposits, especially for its favorable conditions for the removal of gold.

DE - DESCRIPTORS: Andes-; Aratoca-Colombia; boudinage-; Colombia-; deformation-; ductile-deformation; exhumation-; facies-; faults-; folds-; gold-ores; mesothermal-processes; metal-ores; metallogeny-; metamorphic-rocks; metamorphism-; metapelite-; metasedimentary-rocks; mineral-assemblages; mineral-composition; mineral-deposits,-genesis; mineral-exploration; mylonitization-; Paleozoic-; Pescadero-Colombia; Santander-Colombia; Santander-Massif; sequence-stratigraphy; shear-zones; Silgara-Formation; South-America; stratigraphic-units; structural-analysis; structural-controls; tectonics-; veins-

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

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N070000; N080000; LONG: W0723000; W0733000.

IL - ILLUSTRATION: Refs: 12; illus. incl. 1 plate, geol. sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041185

UD - UPDATE CODE: 200412

Registro 115 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Recognition of ancient shoreface deposits, facies, facies successions, and associations; an example from the Cretaceous Gallup clastic wedge, New Mexico.

AU - AUTHORS: Alvarez-Bastos-M

AF - AUTHOR AFFILIATION: Universidad Nacional de Santander, Bucaramanga, Colombia

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 59-79 ; 2 sheets. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: English

LS - LANGUAGE OF SUMMARY: Spanish

AB - ABSTRACT: A high-resolution genetic Stratigraphic study was conducted on the four corners area, New Mexico, USA. Detailed geometric and facial observations made on the Gallup Sandstone allowed to learn about 1. how a Shoreface paleo-depositional environment is incorporated into the stratigraphic record, 2. how it looks like in outcrops, 3. the way time is recorded within it, and 4. dimensions and geometry associated with a shoreface facies tract. Eight main facies were used to characterize a typical facies succession of the shoreface facies tract. These facies are deposited down slope and reflect coexistence of laterally linked subenvironments and an energy trend that decreases from shallow positions to the deeper ones. These facies are reflected in a vertical profile as a consequence of progradation: a lateral migration of laterally linked subenvironments (observed as shingles) along a depositional profile (observed as clinoforms). Application of seminal observations made by Gressly and Walther are used to exemplify the way of identifying shoreface deposits in the stratigraphic record and their associated time lines. Quantification of the geometric and dimensional attributes give us worthy information to be taken into account in reservoir characterization, modeling and simulation.

DE - DESCRIPTORS: basins-; biogenic-structures; biostratigraphy-; bioturbation-; Bivalvia-; Chondrites-ichnofossils; clastic-rocks; clastic-wedges; coastal-environment; Cretaceous-; depositional-environment; facies-; Gallup-Sandstone; ichnofossils-; intertidal-environment; Invertebrata-; mapping-; marine-environment; Mesozoic-; models-; Mollusca-; New-Mexico; paleoenvironment-; petroleum-; petroleum-exploration; progradation-; reservoir-rocks; San-Juan-Basin; sandstone-; sedimentary-basins; sedimentary-rocks; sedimentary-structures; sedimentology-; sequence-stratigraphy; shelf-environment; shorelines-; simulation-; stratigraphic-units; stratigraphic-wedges; United-States; Upper-Cretaceous

CC - CATEGORY CODES: 12-Stratigraphy; 06A-Sedimentary-petrology

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N361500; N365500; LONG: W1084000; W1085500.

IL - ILLUSTRATION: Refs: 5; illus. incl. 5 plates, 1 table, sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041184

UD - UPDATE CODE: 200412

Registro 116 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Introduccion a la geologia del sector Velez-Bolivar-Guavata (Dpto. de Santander, Colombia) y su importancia para la exploracion de depositos hidrotermales

Translated Title: Geology of the Velez-Bolivar-Guavata area (Santander, Colombia) with implications for hydrothermal ore deposit exploration.

AU - AUTHORS: Mantilla-Figueroa-L-C; Cruz-G-L-E; Colegial-G-Juan-Diego

AF - AUTHOR AFFILIATION: Universidad Industrial de Santander, Escuela de Geologia, Bucaramanga, Colombia

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 39-57. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: The studied sector in the Velez Province (Dpto. of Santander, Colombia), presents lower Cretaceous marine sedimentary rocks (Cumbre, Rosablanca, Paja and Tablazo Formations), deformed during the different phases of the Andean Orogeny, which gave rise to structures such as: The Chirle and Velez Anticlines, The Velez Syncline and The Guamito, Pena Negra, Hervedora Faults, among others. The presence of sectors with slaty cleavage; veins filled by brechoid asphaltites, calcite, K-mica, aggregates sphalerite and chlorite, albitites and sulphide bands, among others manifestations, in the influence areas of The Guamito and Pena Negra Faults, are interpreted as products associated to fluid-rock interaction processes. Consequently, these sectors are considered as the greater interest for the exploration of new hydrothermal mineralization (emeralds?).

DE - DESCRIPTORS: Ammonoidea-; Andean-Orogeny; Andes-; assemblages-; biostratigraphy-; Bivalvia-; Bolivar-Colombia; Cephalopoda-; Colombia-; Cretaceous-; Cumbre-Formation; deformation-; El-Guamito-Fault; emerald-; faults-; folds-; foliation-; gems-; Guavata-Colombia; hydrothermal-alteration; Invertebrata-; karst-; Lower-Cretaceous; Mesozoic-; metallogeny-; metasomatism-; mineral-assemblages; mineral-composition; mineral-deposits,-genesis; mineral-exploration; Mollusca-; nonmetal-deposits; Paja-Formation; Pena-Negra-Fault; ring-silicates; Rosablanca-Formation; Santander-Colombia; sedimentary-rocks; silicates-; slaty-cleavage; South-America; stratigraphic-units; structural-analysis; structural-controls; style-; Tablazo-Formation; tectonics-; Tetrabranchiata-; Velez-Colombia

CC - CATEGORY CODES: 26A-Economic-geology,-general,-deposits

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N055000; N061000; LONG: W0733500; W0735500.

IL - ILLUSTRATION: Refs: 34; 3 plates, geol. sketch maps.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041183

UD - UPDATE CODE: 200412

Registro 117 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Cinetica de la nucleacion y el crecimiento del granate en las rocas metapeliticas de la formacion Silgara, region suroccidental del macizo de Santander

Translated Title: Nucleation kinematics and garnet growth in metapelitic rocks of the Silgara Formation, southwestern Santander Massif, Colombia.

AU - AUTHORS: Rios-Reyes-C-A; Gelvez-Llanes-J-R; Marquez-Romero-R-E; Castellanos-Alarcon-O

AF - AUTHOR AFFILIATION: Universidad Industrial de Santander, Escuela de Geologia, Bucaramanga, Colombia

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 23-38. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: Garnet in the Silgara Formation metapelitic rocks that crop out in the southwestern region of the Santander Massif shows different textural varieties and provides valuable information about the deformation history. The Crystal Size Distribution (CSD) analysis of this mineral reveals that it grew between 1.342 and 81.511 years, with nucleation rates decreasing with increasing metamorphic grade. Garnet possibly grew through multivariant reactions combined with high values of critical "overstepping". The nucleation and growth conditions were relatively constant through time and the small deviation of the exponential behavior of CSD reflects that dissolution and "annealing" process were low in magnitude after garnet growth ceased.

DE - DESCRIPTORS: annealing-; Bucaramanga-Fault; chemical-reactions; Colombia-; complexes-; crystal-growth; crystallography-; deformation-; facies-; faults-; garnet-group; geochemistry-; grain-size; kinematics-; mass-transfer; metamorphic-rocks; metamorphism-; metapelite-; metasedimentary-rocks; microscope-methods; mineral-assemblages; mineral-composition; nesosilicates-; nucleation-; orthosilicates-; petrography-; sampling-; Santander-Colombia; Santander-Massif; SEM-data; Silgara-Formation; silicates-; size-distribution; solution-; South-America; statistical-analysis; stratigraphic-units; textures-

CC - CATEGORY CODES: 05A-Igneous-and-metamorphic-petrology; 01B-Mineralogy-of-silicates

DT - DOCUMENT TYPE: Serial

BL - BIB LEVEL: Analytic

MC - MAP COORDINATES: LAT: N070000; N080000; LONG: W0723000; W0733000.

IL - ILLUSTRATION: Refs: 24; illus. incl. 3 tables, sketch map.

RF - REFERENCE SOURCE: GeoRef, Copyright 2004, American Geological Institute.

IS - ISSN: 0120-0283

CO - CODEN: UISBAV

AN - ACCESSION NUMBER: 2004-041182

UD - UPDATE CODE: 200412

Registro 118 de 5614 - GeoRef : 2002-2004/12

TI - TITLE: Termocronologia K-Ar en illitas; aspectos metodologicos

Translated Title: Methodology of K-Ar thermochronology of illite.

AU - AUTHORS: Mantilla-Figueroa-L-C

AF - AUTHOR AFFILIATION: Universidad Industrial de Santander, Escuela de Geologia, Bucaramanga, Colombia

SO - SOURCE: Boletin de Geologia (Bucaramanga). 25; 10, Pages 11-22. 2003.

PB - PUBLISHER: Universidad Industrial de Santander. Bucaramanga, Colombia. 2003.

CP - COUNTRY OF PUBLICATION: Colombia

PY - PUBLICATION YEAR: 2003

LA - LANGUAGE: Spanish

LS - LANGUAGE OF SUMMARY: English

AB - ABSTRACT: The K-Ar dating methods on illites are an important tool for the study of sedimentary basins, hydrothermal events and low- and very low-grade metamorphic rocks. The granulometric fractions that better register the thermal history are those between 2.0-0.4 mu m, 0.4-0.2 mu m and <0.2 mu m, due its high concentration of newformed illites. A preliminary SEM study of the rocks, and the XRD analysis of each granulometric fraction is fundamental to interpret the geological meaning of the obtained isotopic data.