No. Registros Solicitud 1 5614 colombia
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PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 2001. CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2001 CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 2001 annual meeting. Denver, CO, United States. June 3-6, 2001. LA - LANGUAGE: English DE - DESCRIPTORS: body-waves; Cenozoic-; characterization-; Colombia-; cores-; elastic-properties; elastic-waves; enhanced-recovery; giant-fields; heterogeneity-; impedance-; La-Cira-Infantas-Field; models-; oil-and-gas-fields; P-waves; petroleum-; petroleum-engineering; physical-properties; porosity-; reservoir-properties; reservoir-rocks; S-waves; saturation-; secondary-recovery; seismic-waves; South-America; Tertiary-; tertiary-recovery; textures-; three-dimensional-models; velocity-; well-logs CC - CATEGORY CODES: 29A-Economic-geology,-geology-of-energy-sources DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document BL - BIB LEVEL: Analytic RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IS - ISSN: 0094-0038 CO - CODEN: APGAB2 AN - ACCESSION NUMBER: 2003-044695 UD - UPDATE CODE: 200314 Registro 348 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: 3-D seismic structural interpretation of the mature giant oil field La Cira-Infantas, middle Magdalena Valley basin (Colombia). AU - AUTHORS: Gutierrez-Mario-A; Nur-Amos AF - AUTHOR AFFILIATION: Stanford University, Stanford, CA, United States BK - BOOK TITLE: In: American Association of Petroleum Geologists 2001 annual meeting. BA - BOOK AUTHORS: Anonymous SO - SOURCE: Annual Meeting Expanded Abstracts - American Association of Petroleum Geologists. 2001; Pages 77. 2001. PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 2001. CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2001 CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 2001 annual meeting. Denver, CO, United States. June 3-6, 2001. LA - LANGUAGE: English DE - DESCRIPTORS: anticlines-; Cenozoic-; Colombia-; Cretaceous-; displacements-; faults-; folds-; fractures-; geophysical-methods; giant-fields; heterogeneity-; interpretation-; La-Cira-Infantas-Field; low-angle-faults; Magdalena-Valley; Mesozoic-; normal-faults; oil-and-gas-fields; petroleum-; reservoir-rocks; reverse-faults; seismic-methods; South-America; strike-; tectonics-; Tertiary-; three-dimensional-models; thrust-faults; unconformities-; wrench-faults CC - CATEGORY CODES: 29A-Economic-geology,-geology-of-energy-sources; 16-Structural-geology DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document BL - BIB LEVEL: Analytic RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IS - ISSN: 0094-0038 CO - CODEN: APGAB2 AN - ACCESSION NUMBER: 2003-044694 UD - UPDATE CODE: 200314 Registro 349 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: Bypassed oil identification and reservoir monitoring using open- and cased-hole sonic logging, La Cira-Infantas oil field (Colombia). AU - AUTHORS: Gutierrez-Mario-A; Dvorkin-Jack; Nur-Amos AF - AUTHOR AFFILIATION: Stanford University, Stanford, CA, United States BK - BOOK TITLE: In: American Association of Petroleum Geologists 2001 annual meeting. BA - BOOK AUTHORS: Anonymous SO - SOURCE: Annual Meeting Expanded Abstracts - American Association of Petroleum Geologists. 2001; Pages 76. 2001. PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 2001. CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2001 CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 2001 annual meeting. Denver, CO, United States. June 3-6, 2001. LA - LANGUAGE: English DE - DESCRIPTORS: body-waves; Colombia-; elastic-waves; identification-; La-Cira-Infantas-Field; monitoring-; oil-and-gas-fields; P-waves; petroleum-; reservoir-rocks; S-waves; seismic-waves; South-America; velocity-; well-logs CC - CATEGORY CODES: 29A-Economic-geology,-geology-of-energy-sources DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document BL - BIB LEVEL: Analytic RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IS - ISSN: 0094-0038 CO - CODEN: APGAB2 AN - ACCESSION NUMBER: 2003-044693 UD - UPDATE CODE: 200314 Registro 350 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: Rock physics of glauconite and glauconite sandstone reservoirs. AU - AUTHORS: Diaz-Elizabeth; Gutierrez-Mario-A; Dvorkin-Jack; Prasad-Manika; Mavko-Gary AF - AUTHOR AFFILIATION: Stanford University, Stanford, CA, United States BK - BOOK TITLE: In: American Association of Petroleum Geologists 2001 annual meeting. BA - BOOK AUTHORS: Anonymous SO - SOURCE: Annual Meeting Expanded Abstracts - American Association of Petroleum Geologists. 2001; Pages 50. 2001. PB - PUBLISHER: American Association of Petroleum Geologists and Society of Economic Paleontologists and Mineralogists. Tulsa, OK, United States. 2001. CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2001 CN - CONFERENCE INFORMATION: American Association of Petroleum Geologists 2001 annual meeting. Denver, CO, United States. June 3-6, 2001. LA - LANGUAGE: English DE - DESCRIPTORS: acoustical-properties; body-waves; Caballos-Formation; cement-; characterization-; clastic-rocks; Colombia-; correlation-; depositional-environment; elastic-constants; elastic-properties; elastic-waves; geochemistry-; glauconite-; measurement-; mica-group; mineral-composition; P-waves; permeability-; petroleum-; petroleum-engineering; petroleum-exploration; physical-properties; Poisson'-s-ratio; porosity-; prediction-; pressure-; Putumayo-Basin; reservoir-properties; reservoir-rocks; S-waves; sandstone-; sedimentary-rocks; seismic-waves; sheet-silicates; silicates-; South-America; textures-; unconformities-; velocity- CC - CATEGORY CODES: 29A-Economic-geology,-geology-of-energy-sources DT - DOCUMENT TYPE: Abstract; Serial; Conference-Document BL - BIB LEVEL: Analytic RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IS - ISSN: 0094-0038 CO - CODEN: APGAB2 AN - ACCESSION NUMBER: 2003-044677 UD - UPDATE CODE: 200314 Registro 351 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: The use of plate motion vectors to predict the orientation of highly permeable structures in active geothermal fields related to subduction. AU - AUTHORS: Bogie-I AF - AUTHOR AFFILIATION: Sinclair Knight Merz, Auckland, New Zealand BK - BOOK TITLE: In: Proceedings of the 22nd New Zealand geothermal workshop 2000. BA - BOOK AUTHORS: Dunstall-M-G (editor); Morgan-O-E (editor); Simmons-S-F (editor) SO - SOURCE: Pages 69-74. 2000. PB - PUBLISHER: University of Auckland. Auckland, New Zealand. 2000. CP - COUNTRY OF PUBLICATION: New-Zealand PY - PUBLICATION YEAR: 2000 CN - CONFERENCE INFORMATION: 22nd New Zealand geothermal workshop. Auckland, New Zealand. 2000. LA - LANGUAGE: English AB - ABSTRACT: Subduction produces deformation of the upper tectonic plate in a manner that can be predicted from plate motion vectors to indicate whether subduction is perpendicular, weakly oblique or strongly oblique. Perpendicular subduction produces reverse faults parallel to the arc and arc-normal faults, which when the intersection is within a volcanic arc, may localise intrusives with geothermal systems hosted by intrusion margin permeability. Where subduction is slightly oblique, faults with an element of strike-slip motion that strike parallel to the direction of obliqueness can intersect the arc and have associated permeable structures in orientations that can be determined from the strike of the fault and its sense of movement. Where subduction is strongly oblique and subduction is steep, arc-parallel strike-slip faults can form. These frequently run along the volcanic arc and have associated permeable secondary structures whose orientations can be determined similarly. The latter is the optimum tectonic environment for the development of permeable geothermal fields and is found in Sumatra, east-central Philippines, Colombia, Ecuador and southern Chile. DE - DESCRIPTORS: Asia-; Australasia-; Chile-; deformation-; Ecuador-; Far-East; geothermal-energy; geothermal-systems; Indonesia-; island-arcs; Java-; movement-; New-Zealand; North-Island; orientation-; permeability-; Philippine-Islands; plate-collision; plate-tectonics; shear-; South-America; structural-controls; subduction-; Sumatra-; Taupo-volcanic-zone; tectonic-elements; vectors- CC - CATEGORY CODES: 29A-Economic-geology,-geology-of-energy-sources; 18-Solid-earth-geophysics DT - DOCUMENT TYPE: Book; Conference-Document BL - BIB LEVEL: Analytic IL - ILLUSTRATION: Refs: 22; illus. RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. Reference includes data supplied by Institute of Geological and Nuclear Sciences (SIRIS), Lower Hutt, New Zealand IB - ISBN: 0868690244 AN - ACCESSION NUMBER: 2003-044078 UD - UPDATE CODE: 200314 Registro 352 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: The genesis of Colombian emerald deposits; a unique example of beryllium mineralization developed in a black shale environment. AU - AUTHORS: Giuliani-G; Cheilletz-A; Rueda-F; Feraud-G; France-Lanord-C AF - AUTHOR AFFILIATION: CNRS-CRPG, Nancy, France BK - BOOK TITLE: In: Mineral deposits; from their origin to their environmental impacts. BA - BOOK AUTHORS: Pasava-Jan (editor); Kribek-Bohdan (editor); Zak-Karel (editor) SO - SOURCE: Pages 943-946. 1995. PB - PUBLISHER: A.A. Balkema. Rotterdam, Netherlands. 1995. CP - COUNTRY OF PUBLICATION: Netherlands PY - PUBLICATION YEAR: 1995 CN - CONFERENCE INFORMATION: Third biennial SGA Meeting. Prague, Czech Republic. Aug. 28-31, 1995. LA - LANGUAGE: English DE - DESCRIPTORS: beryl-; black-shale; chemically-precipitated-rocks; clastic-rocks; Colombia-; emerald-; evaporites-; fluid-inclusions; hydrothermal-alteration; inclusions-; metasomatism-; mineral-deposits,-genesis; ring-silicates; sedimentary-rocks; silicates-; South-America; veins- CC - CATEGORY CODES: 28A-Economic-geology,-geology-of-nonmetal-deposits DT - DOCUMENT TYPE: Book; Conference-Document BL - BIB LEVEL: Analytic IL - ILLUSTRATION: Refs: 31 RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. Reference includes data supplied by GEOFOND, Prague, Czech Republic IB - ISBN: 90 5410 550 X AN - ACCESSION NUMBER: 2003-042391 UD - UPDATE CODE: 200314 Registro 353 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: Chemistry and source of the high temperature brines in the Colombian emerald deposits. AU - AUTHORS: Banks-D-A; Giuliani-G; Cheilletz-A; Rueda-F AF - AUTHOR AFFILIATION: University of Leeds, Leeds, United Kingdom BK - BOOK TITLE: In: Mineral deposits; from their origin to their environmental impacts. BA - BOOK AUTHORS: Pasava-Jan (editor); Kribek-Bohdan (editor); Zak-Karel (editor) SO - SOURCE: Pages 557-560. 1995. PB - PUBLISHER: A.A. Balkema. Rotterdam, Netherlands. 1995. CP - COUNTRY OF PUBLICATION: Netherlands PY - PUBLICATION YEAR: 1995 CN - CONFERENCE INFORMATION: Third biennial SGA Meeting. Prague, Czech Republic. Aug. 28-31, 1995. LA - LANGUAGE: English DE - DESCRIPTORS: Andes-; brines-; Colombia-; Eastern-Cordillera; emerald-; fluid-inclusions; framework-silicates; gems-; geochemistry-; high-temperature; inclusions-; microthermometry-; mineral-deposits,-genesis; quartz-; ring-silicates; saline-composition; silica-minerals; silicates-; South-America; temperature- CC - CATEGORY CODES: 28A-Economic-geology,-geology-of-nonmetal-deposits DT - DOCUMENT TYPE: Book; Conference-Document BL - BIB LEVEL: Analytic IL - ILLUSTRATION: Refs: 11; illus. incl. 1 table. RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. Reference includes data supplied by GEOFOND, Prague, Czech Republic IB - ISBN: 90 5410 550 X AN - ACCESSION NUMBER: 2003-042296 UD - UPDATE CODE: 200314 Registro 354 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: Morphodynamics of a high discharge tropical delta, San Juan River, Pacific Coast of Colombia. AU - AUTHORS: Restrepo-Juan-D; Kjerfve-Bjorn; Correa-Ivan-D; Gonzalez-Juan AF - AUTHOR AFFILIATION: University of South Carolina, Marine Science Program, Columbia, SC, United States SO - SOURCE: Marine Geology. 192; 4, Pages 355-381. 2002. PB - PUBLISHER: Elsevier. Amsterdam, Netherlands. 2002. CP - COUNTRY OF PUBLICATION: Netherlands PY - PUBLICATION YEAR: 2002 LA - LANGUAGE: English AB - ABSTRACT: The San Juan River has one of the most extensive and best developed deltas on the Pacific coast of South America, measuring 800 km (super 2) . The river drainage basin measures 16 465 km (super 2) and is located in one of the areas with the highest precipitation in the western hemisphere. The annual rainfall varies from 7000 to 11 000 mm, and as a result the San Juan River has the highest water discharge (2550 m (super 3) s (super -1) ), sediment load (16X10 (super 6) t yr (super -1) ), and basin-wide sediment yield (1150 t km (super -2) yr (super -1) ) on the west coast of South America. The San Juan delta growth began approximately 5000 years BP. The structure of the delta is determined by the interactions between fluvial deposition and the effect of 1.7-m significant swells, mostly from the SW, and strong tidal currents. Analysis of delta progradation indicates that during 1848-1992 the morphology of the delta was characterized by beach ridge accretion, spit growth, narrowing of inlets, and a general advance of the delta shoreline. During the past decade processes such as rapid erosion of the delta shore, narrowing of barrier islands, and breaching of a new inlet, are the result of a long-term relative sea-level rise of 2.6 mm yr (super -1) due to tectonically induced subsidence coupled with a eustatic rise of sea-level. The delta also experiences strong oceanographic manifestations associated with the El Nino-La Nina cycle, causing regional sea-level elevation of 20-30 cm during El Nino years. Recent coastal subsidence in the delta is evidenced by: (1) increased occurrence of non-storm washover events; (2) increased erosion of barrier islands with average loss of 11 m yr (super -1) during 1993-1997; and (3) a relative sea-level rise of 3.4 mm yr (super -1) during 1991-1999. The morphology and recent evolution of the San Juan delta are unique when compared to other deltas of South America because of the singular combination of extreme climatic, geologic, and oceanographic conditions under which the delta has formed and the absence of human-induced impact in the drainage basin. DE - DESCRIPTORS: barrier-islands; beach-ridges; bedload-; Cenozoic-; coastal-sedimentation; Colombia-; deltaic-sedimentation; deltas-; discharge-; drainage-basins; El-Nino-Southern-Oscillation; erosion-; erosion-rates; fluvial-sedimentation; geomorphology-; Holocene-; landform-evolution; morphodynamics-; morphology-; ocean-waves; Pacific-Coast; Quaternary-; rivers-and-streams; San-Juan-River; sea-level-changes; sediment-yield; sedimentation-; shore-features; shorelines-; South-America; statistical-analysis; subsidence-; tidal-currents; tidal-inlets; tides-; time-series-analysis; tropical-environment CC - CATEGORY CODES: 23-Geomorphology DT - DOCUMENT TYPE: Serial BL - BIB LEVEL: Analytic MC - MAP COORDINATES: LAT: N035000; N045000; LONG: W0771000; W0773500. IL - ILLUSTRATION: Refs: 79; illus. incl. 4 tables, sketch maps. RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. Reference includes data from CAPCAS, Elsevier Scientific Publishers, Amsterdam, Netherlands IS - ISSN: 0025-3227 CO - CODEN: MAGEA6 AN - ACCESSION NUMBER: 2003-041697 UD - UPDATE CODE: 200313 Registro 355 de 5614 - GeoRef : 2002-2004/12 BK - BOOK TITLE: Stable-isotopic and geochemical assessment of Andean terrestrial ecosystems during Pleistocene climate changes. BA - BOOK AUTHORS: Mora-German CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2000 DG - DEGREE GRANTED: Doctoral DI - DEGREE GRANTING INSTITUTION: Indiana University, Bloomington. Bloomington, IN, United States. Pages: 164. 2000. LA - LANGUAGE: English DE - DESCRIPTORS: Andes-; Bogota-Basin; C-13-C-12; carbon-; Cenozoic-; climate-change; Colombia-; cycles-; D-H; ecosystems-; glaciation-; global-change; hydrogen-; interglacial-environment; isotope-ratios; isotopes-; lacustrine-environment; organic-carbon; organic-compounds; paleoenvironment-; paleohydrology-; Paleosols-; Pleistocene-; productivity-; Quaternary-; South-America; stable-isotopes; sulfur-; terrestrial-environment; vegetation-; weathering- CC - CATEGORY CODES: 24-Quaternary-geology; 02D-Isotope-geochemistry DT - DOCUMENT TYPE: Thesis-or-Dissertation BL - BIB LEVEL: Monograph RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IB - ISBN: 0-599-87302-7 AV - AVAILABILITY: University Microfilms, Ann Arbor, MI, United States AN - ACCESSION NUMBER: 2003-041456 UD - UPDATE CODE: 200313 Registro 356 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: The watershed as an organizing principle for research and development; an evaluation of experience in the Andean ecoregion. AU - AUTHORS: Estrada-Ruben-Dario; Posner-Joshua AF - AUTHOR AFFILIATION: International Center of Tropical Agriculture, Cali, Colombia SO - SOURCE: Mountain Research and Development. 21; 2, Pages 123-127. 2001. PB - PUBLISHER: International Mountain Society. Boulder, CO, United States. 2001. CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2001 LA - LANGUAGE: English AB - ABSTRACT: Watersheds are an attractive unit for development in mountainous landscapes. However, watershed analysis usually requires significantly more time, data and funds, and must include more actors, Also, results may be disappointing. Many off-site effects are very difficult to modify without major changes in land use systems. Frequently, these land use changes (e.g., more pasture or reforestation) pit soil conservation against rural employment. In other cases, sediment may not be originating on-farm, but primarily in other parts of the landscape, implying civil engineering rather than on-farm solutions. On the other hand, we have found that good maps and valid models are of growing interest to municipal authorities as they consider alternative development plans. DE - DESCRIPTORS: Andes-; Cajamarca-Peru; Caldas-Colombia; Colombia-; conservation-; drainage-basins; environmental-effects; environmental-management; human-activity; hydrology-; land-use; Peru-; policy-; South-America; water-management; watersheds- CC - CATEGORY CODES: 22-Environmental-geology DT - DOCUMENT TYPE: Serial BL - BIB LEVEL: Analytic IL - ILLUSTRATION: Refs: 4; illus. incl. 2 tables. RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IS - ISSN: 0276-4741 AN - ACCESSION NUMBER: 2003-039683 UD - UPDATE CODE: 200313 Registro 357 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: Colorful gems; nature's mistakes; impurities impart color and value. AU - AUTHORS: Jones-Bob SO - SOURCE: Rock and Gem. 33; 3, Pages 72-74. 2003. PB - PUBLISHER: Miller Magazines. Ventura, CA, United States. 2003. CP - COUNTRY OF PUBLICATION: United-States PY - PUBLICATION YEAR: 2003 LA - LANGUAGE: English DE - DESCRIPTORS: aluminum-; aquamarine-; beryl-; calcite-; carbonates-; chain-silicates; chromium-; clinopyroxene-; Colombia-; color-; crystal-chemistry; crystal-growth; crystals-; El-Returno-Mine; emerald-; gems-; iron-; kunzite-; manganese-; metals-; Muzo-Colombia; pyroxene-group; ring-silicates; rubies-; silicates-; solutions-; South-America; veins- CC - CATEGORY CODES: 01A-General-mineralogy DT - DOCUMENT TYPE: Serial BL - BIB LEVEL: Analytic IL - ILLUSTRATION: illus. RF - REFERENCE SOURCE: GeoRef, Copyright 2003, American Geological Institute. IS - ISSN: 0048-8453 CO - CODEN: #00310 AN - ACCESSION NUMBER: 2003-038885 UD - UPDATE CODE: 200313 Registro 358 de 5614 - GeoRef : 2002-2004/12 TI - TITLE: Interglacial-glacial Fuquene-3 pollen record from Colombia; an Eemian to Holocene climate record. AU - AUTHORS: van-der-Hammen-Thomas; Hooghiemstra-Henry AF - AUTHOR AFFILIATION: University of Amsterdam, Department of Palynology and Paleo/Actuo-ecology, Amsterdam, Netherlands BK - BOOK TITLE: In: The Eemian interglacial; a global perspective. BA - BOOK AUTHORS: van-Kolfschoten-T (editor); Gibbard-P-L (editor); Knudsen-K-L (editor) SO - SOURCE: Global and Planetary Change. 36; 3, Pages 181-199. 2003. PB - PUBLISHER: Elsevier. Amsterdam, Netherlands. 2003. CP - COUNTRY OF PUBLICATION: Netherlands PY - PUBLICATION YEAR: 2003 LA - LANGUAGE: English AB - ABSTRACT: Pollen analysis of the 43-m-long Fuquene-3 core from Lake Fuquene (5 degrees 27'N, 73 degrees 46'W), located at 2580-m elevation in the Eastern Cordillera of Colombia, shows a record of vegetational and climatic change since the last interglacial. The upper 13 m of lake sediments include six (super 14) C ages ranging from 44,100+ or -200 to 8920+ or -200 (super 14) C years BP, and this core interval is correlated to pollen record Fuquene-2. The lower part of the core is compared with pollen record Fuquene-7 and with the marine oxygen isotope stages (MIS) of the general delta (super 18) O stratigraphy. Cold episodes, corresponding to MIS 2 and MIS 4, are clearly identifiable, whereas a long period with mainly interglacial conditions has been identified as corresponding to MIS 5. The pollen record does not show the transition to the penultimate glacial and is thought to start in the beginning of the last interglacial ("Eemian" or "Palo Blanco" interglacial). The formalised chronostratigraphy of Colombia is partly based on core Fuquene-3: three stadials and three interstadials of early Pleniglacial (73-60 k.y. BP) and middle Pleniglacial (60-28 k.y. BP) time have been recognised. During the two periods, sediments were eroded causing a hiatus from about 36-25 to 18-10 k.y. BP. The upper forest line oscillated between 3300 (max. 14 degrees C at 2550 m) during the last interglacial and about 2000 m (min. 6 degrees C at 2550 m). Compared to today, an LGM temperature depression of 8 degrees C and an Eemian maximum temperature of +1 degrees C at 2550 m have been inferred. Sediment accumulation rates vary from 8 to 3.8 cm/100 years; highest accumulation rates coincide with shallow lake conditions. Upper Andean vegetation is dominated by Quercus forest during the Holocene and by Weinmannia forest during the last interglacial. A slow transition is observed from mild MIS 5 conditions to cool MIS 4 conditions during which period a temperature depression of 4 degrees C compared to today is reconstructed. The temperature record shows two maxima during stage 5a, two minima during stage 5b, stage 5c is relatively short, stage 5d is not represented, and in stage 5e ("Palo Blanco" or "Eemian" interglacial) two maxima are represented: Weinmannia forest dominated during the oldest and Quercus forest dominated during the youngest episode. Yüklə 20,82 Mb. Dostları ilə paylaş:
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