Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador)
An integrated analysis of facies and palaeontological content of the middle to late Miocene (c. 12.4-9.1 Ma) Angostura Formation led to the identification of facies associations indicative of shoreface and inner-shelf settings. The Angostura Formation comprises eight high-frequency sequences that ar...
Published in: | Journal of the Geological Society |
---|---|
Main Authors: | , , , , |
Other Authors: | , , , , |
Format: | Article in Journal/Newspaper |
Language: | English |
Published: |
2007
|
Subjects: | |
Online Access: | http://hdl.handle.net/11568/183279 https://doi.org/10.1144/0016-76492006-001 |
id |
ftunivpisairis:oai:arpi.unipi.it:11568/183279 |
---|---|
record_format |
openpolar |
spelling |
ftunivpisairis:oai:arpi.unipi.it:11568/183279 2024-02-11T09:58:49+01:00 Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) CANTALAMESSA G DI CELMA C VALLERI G RAGAINI, LUCA LANDINI, WALTER Cantalamessa, G DI CELMA, C Ragaini, Luca Valleri, G Landini, Walter 2007 STAMPA http://hdl.handle.net/11568/183279 https://doi.org/10.1144/0016-76492006-001 eng eng info:eu-repo/semantics/altIdentifier/wos/000246329900014 volume:164 issue:3 firstpage:653 lastpage:666 numberofpages:14 journal:JOURNAL OF THE GEOLOGICAL SOCIETY http://hdl.handle.net/11568/183279 doi:10.1144/0016-76492006-001 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-34248163443 Ecuador Angostura Formation Miocene sequence stratigraphy mollusk paleoecology info:eu-repo/semantics/article 2007 ftunivpisairis https://doi.org/10.1144/0016-76492006-001 2024-01-17T17:49:52Z An integrated analysis of facies and palaeontological content of the middle to late Miocene (c. 12.4-9.1 Ma) Angostura Formation led to the identification of facies associations indicative of shoreface and inner-shelf settings. The Angostura Formation comprises eight high-frequency sequences that are stacked to form a tectonically driven lowstand sequence set. The most complete examples of sequences are bounded by transgressively modified unconformities and exhibit a threefold subdivision: (1) a basal suite of deepening-upward shoreface sediments (transgressive systems tract), including a base-of-cycle shell concentration; (2) a mid-cycle shell bed, consisting of molluscan shells dispersed in a matrix of inner-shelf muddy fine-grained sandstones; (3) a shallowing-upward unit of inner-shelf to lower shoreface sediments almost barren of mollusc fossils (highstand systems tract). Biostratigraphic constraints allowed a reasonable correlation between sequence bounding unconformities and the late middle to late Miocene high-frequency glacio-eustatic changes derived from recent δ18O studies. This correlation has far-reaching implications and leads to the following conclusions: (1) glacio-eustasy in tune with oxygen isotope changes at fourth-order frequency (200 ka-1 Ma duration) may have been the principal factor regulating stratigraphic packaging in the Angostura Formation; (2) these sequences provide an excellent shallow-marine outcrop record of late middle to late Miocene Antarctic glaciations. Article in Journal/Newspaper Antarc* Antarctic ARPI - Archivio della Ricerca dell'Università di Pisa Antarctic Journal of the Geological Society 164 3 653 665 |
institution |
Open Polar |
collection |
ARPI - Archivio della Ricerca dell'Università di Pisa |
op_collection_id |
ftunivpisairis |
language |
English |
topic |
Ecuador Angostura Formation Miocene sequence stratigraphy mollusk paleoecology |
spellingShingle |
Ecuador Angostura Formation Miocene sequence stratigraphy mollusk paleoecology CANTALAMESSA G DI CELMA C VALLERI G RAGAINI, LUCA LANDINI, WALTER Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) |
topic_facet |
Ecuador Angostura Formation Miocene sequence stratigraphy mollusk paleoecology |
description |
An integrated analysis of facies and palaeontological content of the middle to late Miocene (c. 12.4-9.1 Ma) Angostura Formation led to the identification of facies associations indicative of shoreface and inner-shelf settings. The Angostura Formation comprises eight high-frequency sequences that are stacked to form a tectonically driven lowstand sequence set. The most complete examples of sequences are bounded by transgressively modified unconformities and exhibit a threefold subdivision: (1) a basal suite of deepening-upward shoreface sediments (transgressive systems tract), including a base-of-cycle shell concentration; (2) a mid-cycle shell bed, consisting of molluscan shells dispersed in a matrix of inner-shelf muddy fine-grained sandstones; (3) a shallowing-upward unit of inner-shelf to lower shoreface sediments almost barren of mollusc fossils (highstand systems tract). Biostratigraphic constraints allowed a reasonable correlation between sequence bounding unconformities and the late middle to late Miocene high-frequency glacio-eustatic changes derived from recent δ18O studies. This correlation has far-reaching implications and leads to the following conclusions: (1) glacio-eustasy in tune with oxygen isotope changes at fourth-order frequency (200 ka-1 Ma duration) may have been the principal factor regulating stratigraphic packaging in the Angostura Formation; (2) these sequences provide an excellent shallow-marine outcrop record of late middle to late Miocene Antarctic glaciations. |
author2 |
Cantalamessa, G DI CELMA, C Ragaini, Luca Valleri, G Landini, Walter |
format |
Article in Journal/Newspaper |
author |
CANTALAMESSA G DI CELMA C VALLERI G RAGAINI, LUCA LANDINI, WALTER |
author_facet |
CANTALAMESSA G DI CELMA C VALLERI G RAGAINI, LUCA LANDINI, WALTER |
author_sort |
CANTALAMESSA G |
title |
Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) |
title_short |
Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) |
title_full |
Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) |
title_fullStr |
Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) |
title_full_unstemmed |
Sedimentology and high resolution sequence stratigraphy of the late middle to late Miocene Angostura Formation (western Borbón Basin, north-western Ecuador) |
title_sort |
sedimentology and high resolution sequence stratigraphy of the late middle to late miocene angostura formation (western borbón basin, north-western ecuador) |
publishDate |
2007 |
url |
http://hdl.handle.net/11568/183279 https://doi.org/10.1144/0016-76492006-001 |
geographic |
Antarctic |
geographic_facet |
Antarctic |
genre |
Antarc* Antarctic |
genre_facet |
Antarc* Antarctic |
op_relation |
info:eu-repo/semantics/altIdentifier/wos/000246329900014 volume:164 issue:3 firstpage:653 lastpage:666 numberofpages:14 journal:JOURNAL OF THE GEOLOGICAL SOCIETY http://hdl.handle.net/11568/183279 doi:10.1144/0016-76492006-001 info:eu-repo/semantics/altIdentifier/scopus/2-s2.0-34248163443 |
op_doi |
https://doi.org/10.1144/0016-76492006-001 |
container_title |
Journal of the Geological Society |
container_volume |
164 |
container_issue |
3 |
container_start_page |
653 |
op_container_end_page |
665 |
_version_ |
1790594587443593216 |