Repository logo
 
Publication

The insular shelves of the Faial-Pico Ridge (Azores archipelago): a morphological record of its evolution

2015-05Journal article Restricted access
Simple item page
dc.contributor.authorQuartau, Rui
dc.contributor.authorMadeira, JFA
dc.contributor.authorMitchell, N. C.
dc.contributor.authorTempera, F.
dc.contributor.authorSilva, Pedro F.
dc.contributor.authorBrandão, F.
dc.date.accessioned2016-04-28T10:02:23Z
dc.date.available2016-04-28T10:02:23Z
dc.date.issued2015-05
dc.description.abstractShelves surrounding reefless volcanic ocean islands are formed by surf erosion of their slopes during changing sea levels. Posterosional lava flows, if abundant, can cross the coastal cliffs and fill partially or completely the accommodation space left by erosion. In this study, multibeam bathymetry, high-resolution seismic reflection profiles, and sediment samples are used to characterize the morphology of the insular shelves adjacent to Pico Island. The data show offshore fresh lava flow morphologies, as well as an irregular basement beneath shelf sedimentary bodies and reduced shelf width adjacent to older volcanic edifices in Pico. These observations suggest that these shelves have been significantly filled by volcanic progradation and can thus be classified as rejuvenated. Despite the general volcanic infilling of the shelves around Pico, most of their edges are below the depth of the Last Glacial Maximum, revealing that at least parts of the island have subsided after the shelves formed by surf erosion. Prograding lava deltas reached the shelf edge in some areas triggering small slope failures, locally decreasing the shelf width and depth of their edges. These areas can represent a significant risk for the local population; hence, their identification can be useful for hazard assessment and contribute to wiser land use planning. Shelf and subaerial geomorphology, magnetic anomalies and crustal structure data of the two islands were also interpreted to reconstruct the long-term combined onshore and offshore evolution of the Faial-Pico ridge. The subaerial emergence of this ridge is apparently older than previously thought, i.e., before approximate to 850 ka.pt_PT
dc.identifier.citationQUARTAU, Rui; [et al] - he insular shelves of the Faial-Pico Ridge (Azores archipelago): a morphological record of its evolution. Geochemistry Geophysics Geosystems. ISSN 1525-2027. Vol. 16, N.º 5 (2015), pp. 1401-1420pt_PT
dc.identifier.doi10.1002/2015GC005733pt_PT
dc.identifier.issn1525-2027
dc.identifier.urihttp://hdl.handle.net/10400.21/6109
dc.language.isoengpt_PT
dc.peerreviewedyespt_PT
dc.publisherAmer Geophysical Unionpt_PT
dc.subjectVolcanic ocean islandpt_PT
dc.subjectShelf developmentpt_PT
dc.subjectCoastal erosionpt_PT
dc.subjectLava progradationpt_PT
dc.subjectMass wastingpt_PT
dc.subjectGeological evolutionpt_PT
dc.titleThe insular shelves of the Faial-Pico Ridge (Azores archipelago): a morphological record of its evolutionpt_PT
dc.typejournal article
dspace.entity.typePublication
oaire.citation.endPage1420pt_PT
oaire.citation.issue5pt_PT
oaire.citation.startPage1401pt_PT
oaire.citation.titleGeochemistry Geophysics Geosystemspt_PT
oaire.citation.volume16pt_PT
person.familyNameMadeira
person.givenNameJose Firmino Aguilar
person.identifier.ciencia-id6F1E-DCF0-D6EC
person.identifier.orcid0000-0001-9523-3808
person.identifier.ridN-6918-2016
person.identifier.scopus-author-id7003405549
rcaap.rightsclosedAccesspt_PT
rcaap.typearticlept_PT
relation.isAuthorOfPublicationd495619a-a6ab-4ff5-8e70-3a1351f934dc
relation.isAuthorOfPublication.latestForDiscoveryd495619a-a6ab-4ff5-8e70-3a1351f934dc

Files

Original bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
The insular shelves of the Faial-Pico ridge (Azores archipelago) - a morphological record of its evolution.pdf
Size:
2.24 MB
Format:
Adobe Portable Document Format
Download
License bundle
Now showing 1 - 1 of 1
No Thumbnail Available
Name:
license.txt
Size:
1.71 KB
Format:
Item-specific license agreed upon to submission
Description:
Download

Collections

ISEL - Física - Artigos