Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flo...
- Autores
- Dykstra, Mason; Kneller, Ben; Milana, Juan Pablo
- Año de publicación
- 2011
- Idioma
- inglés
- Tipo de recurso
- artículo
- Estado
- versión publicada
- Descripción
- Preserved in Quebrada de las Lajas, near San Juan, Argentina, is an ancient subaqueous proglacial sedimentary succession that includes a small-scale (ca 50 m thick and ca 200 m wide) channel–levee system with excellent exposure of the channel axis and levee sediments. Coeval deposition of both the channel axis and the levees can be demonstrated clearly by lateral correlation of individual beds. The channel axis consists predominantly of a disorganized, pebble to boulder conglomerate with a poorly sorted matrix. The channel axis varies from 10 to 20 m wide and has a total amalgamated thickness of around 50 m. Beds fine gradationally away from the cobble–boulder conglomerates of the channel axis within a few metres, transitioning to well-organized pebble to cobble conglomerates and sandstones of the channel margin. Within 60 m outboard of the channel axis in both directions, perpendicular to the trend of the channel axis, the mean grain size of the beds in the levees is silt to fine-grained sand. Deposits in this channel–levee system are the product of both debris flows (channel axis) and co-genetic turbidity currents (channel margins and levees). Bed thicknesses in the levees increase for up to 10 to 25 m away from the channel axis, beyond which bed thicknesses decrease with increasing distance. The positions of the bed thickness maxima define the levee crests, and the thinning beds constitute the outer levee slopes. From these relationships it is clear that the levee crest migrated both away from and toward the channel axis, and varied in height above the channel axis from 4 to 5 m (undecompacted), whereas the height of the levee crest relative to the distal levee varied from 4.5 to 10 m, indicating that the channel was at times super-elevated relative to the distal levee. Bed thickness decay on the outside of the levee crest can be described quite well with a power-law function (R2=0.85), whereas the thickness decay from the levee crest toward the channel axis follows a linear function (R2 =0.78). Grain-size changes are quite predictable from the channel margin outward, and follow logarithmic (R2=0.77) or power-law (R2=0.72) decay curves, either of which fit the data quite well. This study demonstrates that, in at least this case: (i) levee thickness trends can be directly related to channel-flow processes; (ii) individual bed thickness changes may control overall levee geometry; and (iii) levee and channel deposits can be coeval.
Fil: Dykstra, Mason. Colorado School of Mines; Estados Unidos
Fil: Kneller, Ben. University of Aberdeen; Reino Unido
Fil: Milana, Juan Pablo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Geología "Dr. Emiliano Aparicio"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina - Materia
-
BED THICKNESS DECAY
CARBONIFEROUS
CHANNEL
CHANNEL-LEVÉE
DEBRIS-FLOW
DEGLACIAL
PRO-GLACIAL
TURBIDITY CURRENT - Nivel de accesibilidad
- acceso abierto
- Condiciones de uso
- https://creativecommons.org/licenses/by-nc-sa/2.5/ar/
- Repositorio
- Institución
- Consejo Nacional de Investigaciones Científicas y Técnicas
- OAI Identificador
- oai:ri.conicet.gov.ar:11336/188887
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spelling |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processesDykstra, MasonKneller, BenMilana, Juan PabloBED THICKNESS DECAYCARBONIFEROUSCHANNELCHANNEL-LEVÉEDEBRIS-FLOWDEGLACIALPRO-GLACIALTURBIDITY CURRENThttps://purl.org/becyt/ford/1.5https://purl.org/becyt/ford/1Preserved in Quebrada de las Lajas, near San Juan, Argentina, is an ancient subaqueous proglacial sedimentary succession that includes a small-scale (ca 50 m thick and ca 200 m wide) channel–levee system with excellent exposure of the channel axis and levee sediments. Coeval deposition of both the channel axis and the levees can be demonstrated clearly by lateral correlation of individual beds. The channel axis consists predominantly of a disorganized, pebble to boulder conglomerate with a poorly sorted matrix. The channel axis varies from 10 to 20 m wide and has a total amalgamated thickness of around 50 m. Beds fine gradationally away from the cobble–boulder conglomerates of the channel axis within a few metres, transitioning to well-organized pebble to cobble conglomerates and sandstones of the channel margin. Within 60 m outboard of the channel axis in both directions, perpendicular to the trend of the channel axis, the mean grain size of the beds in the levees is silt to fine-grained sand. Deposits in this channel–levee system are the product of both debris flows (channel axis) and co-genetic turbidity currents (channel margins and levees). Bed thicknesses in the levees increase for up to 10 to 25 m away from the channel axis, beyond which bed thicknesses decrease with increasing distance. The positions of the bed thickness maxima define the levee crests, and the thinning beds constitute the outer levee slopes. From these relationships it is clear that the levee crest migrated both away from and toward the channel axis, and varied in height above the channel axis from 4 to 5 m (undecompacted), whereas the height of the levee crest relative to the distal levee varied from 4.5 to 10 m, indicating that the channel was at times super-elevated relative to the distal levee. Bed thickness decay on the outside of the levee crest can be described quite well with a power-law function (R2=0.85), whereas the thickness decay from the levee crest toward the channel axis follows a linear function (R2 =0.78). Grain-size changes are quite predictable from the channel margin outward, and follow logarithmic (R2=0.77) or power-law (R2=0.72) decay curves, either of which fit the data quite well. This study demonstrates that, in at least this case: (i) levee thickness trends can be directly related to channel-flow processes; (ii) individual bed thickness changes may control overall levee geometry; and (iii) levee and channel deposits can be coeval.Fil: Dykstra, Mason. Colorado School of Mines; Estados UnidosFil: Kneller, Ben. University of Aberdeen; Reino UnidoFil: Milana, Juan Pablo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Geología "Dr. Emiliano Aparicio"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; ArgentinaWiley Blackwell Publishing, Inc2011-07info:eu-repo/semantics/articleinfo:eu-repo/semantics/publishedVersionhttp://purl.org/coar/resource_type/c_6501info:ar-repo/semantics/articuloapplication/pdfapplication/pdfhttp://hdl.handle.net/11336/188887Dykstra, Mason; Kneller, Ben; Milana, Juan Pablo; Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes; Wiley Blackwell Publishing, Inc; Sedimentology; 59; 2; 7-2011; 605-6220037-0746CONICET DigitalCONICETenginfo:eu-repo/semantics/altIdentifier/doi/ 10.1111/j.1365-3091.2011.01268.xinfo:eu-repo/semantics/altIdentifier/url/https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3091.2011.01268.xinfo:eu-repo/semantics/openAccesshttps://creativecommons.org/licenses/by-nc-sa/2.5/ar/reponame:CONICET Digital (CONICET)instname:Consejo Nacional de Investigaciones Científicas y Técnicas2025-09-29T09:34:55Zoai:ri.conicet.gov.ar:11336/188887instacron:CONICETInstitucionalhttp://ri.conicet.gov.ar/Organismo científico-tecnológicoNo correspondehttp://ri.conicet.gov.ar/oai/requestdasensio@conicet.gov.ar; lcarlino@conicet.gov.arArgentinaNo correspondeNo correspondeNo correspondeopendoar:34982025-09-29 09:34:56.132CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicasfalse |
dc.title.none.fl_str_mv |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
title |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
spellingShingle |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes Dykstra, Mason BED THICKNESS DECAY CARBONIFEROUS CHANNEL CHANNEL-LEVÉE DEBRIS-FLOW DEGLACIAL PRO-GLACIAL TURBIDITY CURRENT |
title_short |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
title_full |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
title_fullStr |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
title_full_unstemmed |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
title_sort |
Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes |
dc.creator.none.fl_str_mv |
Dykstra, Mason Kneller, Ben Milana, Juan Pablo |
author |
Dykstra, Mason |
author_facet |
Dykstra, Mason Kneller, Ben Milana, Juan Pablo |
author_role |
author |
author2 |
Kneller, Ben Milana, Juan Pablo |
author2_role |
author author |
dc.subject.none.fl_str_mv |
BED THICKNESS DECAY CARBONIFEROUS CHANNEL CHANNEL-LEVÉE DEBRIS-FLOW DEGLACIAL PRO-GLACIAL TURBIDITY CURRENT |
topic |
BED THICKNESS DECAY CARBONIFEROUS CHANNEL CHANNEL-LEVÉE DEBRIS-FLOW DEGLACIAL PRO-GLACIAL TURBIDITY CURRENT |
purl_subject.fl_str_mv |
https://purl.org/becyt/ford/1.5 https://purl.org/becyt/ford/1 |
dc.description.none.fl_txt_mv |
Preserved in Quebrada de las Lajas, near San Juan, Argentina, is an ancient subaqueous proglacial sedimentary succession that includes a small-scale (ca 50 m thick and ca 200 m wide) channel–levee system with excellent exposure of the channel axis and levee sediments. Coeval deposition of both the channel axis and the levees can be demonstrated clearly by lateral correlation of individual beds. The channel axis consists predominantly of a disorganized, pebble to boulder conglomerate with a poorly sorted matrix. The channel axis varies from 10 to 20 m wide and has a total amalgamated thickness of around 50 m. Beds fine gradationally away from the cobble–boulder conglomerates of the channel axis within a few metres, transitioning to well-organized pebble to cobble conglomerates and sandstones of the channel margin. Within 60 m outboard of the channel axis in both directions, perpendicular to the trend of the channel axis, the mean grain size of the beds in the levees is silt to fine-grained sand. Deposits in this channel–levee system are the product of both debris flows (channel axis) and co-genetic turbidity currents (channel margins and levees). Bed thicknesses in the levees increase for up to 10 to 25 m away from the channel axis, beyond which bed thicknesses decrease with increasing distance. The positions of the bed thickness maxima define the levee crests, and the thinning beds constitute the outer levee slopes. From these relationships it is clear that the levee crest migrated both away from and toward the channel axis, and varied in height above the channel axis from 4 to 5 m (undecompacted), whereas the height of the levee crest relative to the distal levee varied from 4.5 to 10 m, indicating that the channel was at times super-elevated relative to the distal levee. Bed thickness decay on the outside of the levee crest can be described quite well with a power-law function (R2=0.85), whereas the thickness decay from the levee crest toward the channel axis follows a linear function (R2 =0.78). Grain-size changes are quite predictable from the channel margin outward, and follow logarithmic (R2=0.77) or power-law (R2=0.72) decay curves, either of which fit the data quite well. This study demonstrates that, in at least this case: (i) levee thickness trends can be directly related to channel-flow processes; (ii) individual bed thickness changes may control overall levee geometry; and (iii) levee and channel deposits can be coeval. Fil: Dykstra, Mason. Colorado School of Mines; Estados Unidos Fil: Kneller, Ben. University of Aberdeen; Reino Unido Fil: Milana, Juan Pablo. Universidad Nacional de San Juan. Facultad de Ciencias Exactas, Físicas y Naturales. Instituto de Geología "Dr. Emiliano Aparicio"; Argentina. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - San Juan; Argentina |
description |
Preserved in Quebrada de las Lajas, near San Juan, Argentina, is an ancient subaqueous proglacial sedimentary succession that includes a small-scale (ca 50 m thick and ca 200 m wide) channel–levee system with excellent exposure of the channel axis and levee sediments. Coeval deposition of both the channel axis and the levees can be demonstrated clearly by lateral correlation of individual beds. The channel axis consists predominantly of a disorganized, pebble to boulder conglomerate with a poorly sorted matrix. The channel axis varies from 10 to 20 m wide and has a total amalgamated thickness of around 50 m. Beds fine gradationally away from the cobble–boulder conglomerates of the channel axis within a few metres, transitioning to well-organized pebble to cobble conglomerates and sandstones of the channel margin. Within 60 m outboard of the channel axis in both directions, perpendicular to the trend of the channel axis, the mean grain size of the beds in the levees is silt to fine-grained sand. Deposits in this channel–levee system are the product of both debris flows (channel axis) and co-genetic turbidity currents (channel margins and levees). Bed thicknesses in the levees increase for up to 10 to 25 m away from the channel axis, beyond which bed thicknesses decrease with increasing distance. The positions of the bed thickness maxima define the levee crests, and the thinning beds constitute the outer levee slopes. From these relationships it is clear that the levee crest migrated both away from and toward the channel axis, and varied in height above the channel axis from 4 to 5 m (undecompacted), whereas the height of the levee crest relative to the distal levee varied from 4.5 to 10 m, indicating that the channel was at times super-elevated relative to the distal levee. Bed thickness decay on the outside of the levee crest can be described quite well with a power-law function (R2=0.85), whereas the thickness decay from the levee crest toward the channel axis follows a linear function (R2 =0.78). Grain-size changes are quite predictable from the channel margin outward, and follow logarithmic (R2=0.77) or power-law (R2=0.72) decay curves, either of which fit the data quite well. This study demonstrates that, in at least this case: (i) levee thickness trends can be directly related to channel-flow processes; (ii) individual bed thickness changes may control overall levee geometry; and (iii) levee and channel deposits can be coeval. |
publishDate |
2011 |
dc.date.none.fl_str_mv |
2011-07 |
dc.type.none.fl_str_mv |
info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion http://purl.org/coar/resource_type/c_6501 info:ar-repo/semantics/articulo |
format |
article |
status_str |
publishedVersion |
dc.identifier.none.fl_str_mv |
http://hdl.handle.net/11336/188887 Dykstra, Mason; Kneller, Ben; Milana, Juan Pablo; Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes; Wiley Blackwell Publishing, Inc; Sedimentology; 59; 2; 7-2011; 605-622 0037-0746 CONICET Digital CONICET |
url |
http://hdl.handle.net/11336/188887 |
identifier_str_mv |
Dykstra, Mason; Kneller, Ben; Milana, Juan Pablo; Bed-thickness and grain-size trends in a small-scale proglacial channel-levée system; the Carboniferous Jejenes Formation, Western Argentina: Implications for turbidity current flow processes; Wiley Blackwell Publishing, Inc; Sedimentology; 59; 2; 7-2011; 605-622 0037-0746 CONICET Digital CONICET |
dc.language.none.fl_str_mv |
eng |
language |
eng |
dc.relation.none.fl_str_mv |
info:eu-repo/semantics/altIdentifier/doi/ 10.1111/j.1365-3091.2011.01268.x info:eu-repo/semantics/altIdentifier/url/https://onlinelibrary.wiley.com/doi/abs/10.1111/j.1365-3091.2011.01268.x |
dc.rights.none.fl_str_mv |
info:eu-repo/semantics/openAccess https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
eu_rights_str_mv |
openAccess |
rights_invalid_str_mv |
https://creativecommons.org/licenses/by-nc-sa/2.5/ar/ |
dc.format.none.fl_str_mv |
application/pdf application/pdf |
dc.publisher.none.fl_str_mv |
Wiley Blackwell Publishing, Inc |
publisher.none.fl_str_mv |
Wiley Blackwell Publishing, Inc |
dc.source.none.fl_str_mv |
reponame:CONICET Digital (CONICET) instname:Consejo Nacional de Investigaciones Científicas y Técnicas |
reponame_str |
CONICET Digital (CONICET) |
collection |
CONICET Digital (CONICET) |
instname_str |
Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.name.fl_str_mv |
CONICET Digital (CONICET) - Consejo Nacional de Investigaciones Científicas y Técnicas |
repository.mail.fl_str_mv |
dasensio@conicet.gov.ar; lcarlino@conicet.gov.ar |
_version_ |
1844613084249849856 |
score |
13.070432 |