Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia
Laguna Potrok Aike is a maar lake located in the Pali Aike Volcanic Field in Southern Patagonia,Argentina, at about 52°S and 70°W. The lake with a diameter of about 3.5 km is almost circular and bowl-shaped with a deep, flat plain (about 100 m water depth) in its central part. Steep flanks separate...
Main Authors: | , , , , , , , |
---|---|
Format: | Conference Object |
Language: | unknown |
Published: |
2007
|
Subjects: | |
Online Access: | https://epic.awi.de/id/eprint/17167/ https://hdl.handle.net/10013/epic.27006 |
id |
ftawi:oai:epic.awi.de:17167 |
---|---|
record_format |
openpolar |
spelling |
ftawi:oai:epic.awi.de:17167 2023-05-15T13:39:47+02:00 Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia Gebhardt, Catalina Niessen, Frank Anselmetti, F. Ariztegui, D. De Batist, M. Haberzettl, T. Ohlendorf, C. Zolitschka, B. 2007 https://epic.awi.de/id/eprint/17167/ https://hdl.handle.net/10013/epic.27006 unknown Gebhardt, C. orcid:0000-0002-3227-0676 , Niessen, F. orcid:0000-0001-6453-0594 , Anselmetti, F. , Ariztegui, D. , De Batist, M. , Haberzettl, T. , Ohlendorf, C. and Zolitschka, B. (2007) Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia , 4th International Limnogeology Congress, 11-14 July 2007, Barcelona. . hdl:10013/epic.27006 EPIC34th International Limnogeology Congress, 11-14 July 2007, Barcelona. Conference notRev 2007 ftawi 2021-12-24T15:32:02Z Laguna Potrok Aike is a maar lake located in the Pali Aike Volcanic Field in Southern Patagonia,Argentina, at about 52°S and 70°W. The lake with a diameter of about 3.5 km is almost circular and bowl-shaped with a deep, flat plain (about 100 m water depth) in its central part. Steep flanks separate the central plain from the lake shoulders in 15 to 30 m water depth. The lake is located at the present boundary between the Southern Hemispheric Westerlies and the Antarctic Polar Front. It is highly susceptible to changes in the Antarctic Circumpolar Current controlling the regional precipitation patterns. Its sediments possibly contain a long and continuous record of several glacial and interglacial cycles, which is unique in the southern South American realm.In a first step towards continental deep drilling, four seismic surveys were carried out between 2003 and 2005 to reveal the general geometry of the maar crater as well as the internal structures and thickness of the lacustrine sediments, their spatial distribution and possible lithologies.Two major stratigraphic units were distinguished in the seismic sections, Unit I consisting of thelacustrine infill and Unit II forming the surrounding and underlying bedrock. Unit I was further subdivided into Sub-units I-a and I-b on the lake shoulders and I-ab, I-c and I-d in the central basin.The sediments of Unit I are generally well-layered. Sub-units I-a and I-b on the lake shoulders areseparated by a major unconformity and contain several paleoshoreline structures formed during a step-wise transgression after a lake level lowstand of approx. 35 m below the present lake level. In the central basin, Sub-units I-a and I-b are merged into Sub-unit I-ab, not being separated by any unconformity. Pelagic sedimentation dominates in the northern and central parts, whereas mass movement deposits were found in the southern, western and eastern parts close to the steep diatreme flanks. The boundary between I-ab and I-c is non-erosive with I-ab forming downlaps onto I-c from the eastern and western parts of the lake, pointing at a significantly lower lake level during its accumulation. Sub-unit I-d shows similar characteristics as I-ab. The bedrock (Unit II) that forms the steep diatreme flanks consists of the well-layered sandstones found in outcrops of the lake surroundings. Conference Object Antarc* Antarctic Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) Antarctic Argentina Central Basin ENVELOPE(178.000,178.000,-72.300,-72.300) Lower Lake ENVELOPE(-129.290,-129.290,53.428,53.428) Patagonia The Antarctic |
institution |
Open Polar |
collection |
Alfred Wegener Institute for Polar- and Marine Research (AWI): ePIC (electronic Publication Information Center) |
op_collection_id |
ftawi |
language |
unknown |
description |
Laguna Potrok Aike is a maar lake located in the Pali Aike Volcanic Field in Southern Patagonia,Argentina, at about 52°S and 70°W. The lake with a diameter of about 3.5 km is almost circular and bowl-shaped with a deep, flat plain (about 100 m water depth) in its central part. Steep flanks separate the central plain from the lake shoulders in 15 to 30 m water depth. The lake is located at the present boundary between the Southern Hemispheric Westerlies and the Antarctic Polar Front. It is highly susceptible to changes in the Antarctic Circumpolar Current controlling the regional precipitation patterns. Its sediments possibly contain a long and continuous record of several glacial and interglacial cycles, which is unique in the southern South American realm.In a first step towards continental deep drilling, four seismic surveys were carried out between 2003 and 2005 to reveal the general geometry of the maar crater as well as the internal structures and thickness of the lacustrine sediments, their spatial distribution and possible lithologies.Two major stratigraphic units were distinguished in the seismic sections, Unit I consisting of thelacustrine infill and Unit II forming the surrounding and underlying bedrock. Unit I was further subdivided into Sub-units I-a and I-b on the lake shoulders and I-ab, I-c and I-d in the central basin.The sediments of Unit I are generally well-layered. Sub-units I-a and I-b on the lake shoulders areseparated by a major unconformity and contain several paleoshoreline structures formed during a step-wise transgression after a lake level lowstand of approx. 35 m below the present lake level. In the central basin, Sub-units I-a and I-b are merged into Sub-unit I-ab, not being separated by any unconformity. Pelagic sedimentation dominates in the northern and central parts, whereas mass movement deposits were found in the southern, western and eastern parts close to the steep diatreme flanks. The boundary between I-ab and I-c is non-erosive with I-ab forming downlaps onto I-c from the eastern and western parts of the lake, pointing at a significantly lower lake level during its accumulation. Sub-unit I-d shows similar characteristics as I-ab. The bedrock (Unit II) that forms the steep diatreme flanks consists of the well-layered sandstones found in outcrops of the lake surroundings. |
format |
Conference Object |
author |
Gebhardt, Catalina Niessen, Frank Anselmetti, F. Ariztegui, D. De Batist, M. Haberzettl, T. Ohlendorf, C. Zolitschka, B. |
spellingShingle |
Gebhardt, Catalina Niessen, Frank Anselmetti, F. Ariztegui, D. De Batist, M. Haberzettl, T. Ohlendorf, C. Zolitschka, B. Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia |
author_facet |
Gebhardt, Catalina Niessen, Frank Anselmetti, F. Ariztegui, D. De Batist, M. Haberzettl, T. Ohlendorf, C. Zolitschka, B. |
author_sort |
Gebhardt, Catalina |
title |
Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia |
title_short |
Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia |
title_full |
Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia |
title_fullStr |
Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia |
title_full_unstemmed |
Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia |
title_sort |
seismic investigation of sedimentary fill and bedrock geometry of maar lake laguna potrok aike, southern patagonia |
publishDate |
2007 |
url |
https://epic.awi.de/id/eprint/17167/ https://hdl.handle.net/10013/epic.27006 |
long_lat |
ENVELOPE(178.000,178.000,-72.300,-72.300) ENVELOPE(-129.290,-129.290,53.428,53.428) |
geographic |
Antarctic Argentina Central Basin Lower Lake Patagonia The Antarctic |
geographic_facet |
Antarctic Argentina Central Basin Lower Lake Patagonia The Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_source |
EPIC34th International Limnogeology Congress, 11-14 July 2007, Barcelona. |
op_relation |
Gebhardt, C. orcid:0000-0002-3227-0676 , Niessen, F. orcid:0000-0001-6453-0594 , Anselmetti, F. , Ariztegui, D. , De Batist, M. , Haberzettl, T. , Ohlendorf, C. and Zolitschka, B. (2007) Seismic investigation of sedimentary fill and bedrock geometry of maar lake Laguna Potrok Aike, Southern Patagonia , 4th International Limnogeology Congress, 11-14 July 2007, Barcelona. . hdl:10013/epic.27006 |
_version_ |
1766124222497685504 |