Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal)
The neotectonics of the islands of Faial, Pico and S. Jorge (Azores) is presented. Preliminary paleoseismology data from trench exposures across three active fault zones (Lomba do Meio, Lagoa do Capitão and Pico do Carvão faults) complement the information. Radiocarbon age constrai...
| Main Authors: | , |
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| Format: | Article |
| Language: | English |
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Istituto Nazionale di Geofisica e Vulcanologia (INGV)
2003-06-01
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| Series: | Annals of Geophysics |
| Subjects: | |
| Online Access: | http://www.annalsofgeophysics.eu/index.php/annals/article/view/3453 |
| _version_ | 1818765776415358976 |
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| author | A. Brum da Silveira J. Madeira |
| author_facet | A. Brum da Silveira J. Madeira |
| author_sort | A. Brum da Silveira |
| collection | DOAJ |
| description | The neotectonics of the islands of Faial, Pico and S. Jorge (Azores) is presented. Preliminary paleoseismology data from trench exposures across three active fault zones (Lomba do Meio, Lagoa do Capitão and Pico do Carvão faults) complement the information. Radiocarbon age constraints of paleoearthquakes suggest clustering of surface rupturing events. Slip rates deduced from paleoseismology analysis range from 0.10 to 0.40 cm/year and validate long-term slip rates obtained by neotectonic studies (using Pleistocene markers). The studied faults allowed a preliminary seismic hazard assessment: magnitudes of the largest paleoearthquakes, determined from slip per event range from Mw = 6.9 to 7.1, and maximum expected magnitudes, estimated from rupture length or rupture area, vary from Mw = 6.4 to 6.8. The former Mw estimates are in closer agreement with the magnitude of the major historic and instrumental seismic events in the archipelago, even though the used empirical relations between magnitude and rupture parameters may not be the most adequate due to the unique tectonic setting of Azores. |
| first_indexed | 2024-12-18T08:23:28Z |
| format | Article |
| id | doaj.art-62bc85e91a534220bdd35be1aa57af8a |
| institution | Directory Open Access Journal |
| issn | 1593-5213 2037-416X |
| language | English |
| last_indexed | 2024-12-18T08:23:28Z |
| publishDate | 2003-06-01 |
| publisher | Istituto Nazionale di Geofisica e Vulcanologia (INGV) |
| record_format | Article |
| series | Annals of Geophysics |
| spelling | doaj.art-62bc85e91a534220bdd35be1aa57af8a2022-12-21T21:14:41ZengIstituto Nazionale di Geofisica e Vulcanologia (INGV)Annals of Geophysics1593-52132037-416X2003-06-0146510.4401/ag-3453Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal)A. Brum da SilveiraJ. MadeiraThe neotectonics of the islands of Faial, Pico and S. Jorge (Azores) is presented. Preliminary paleoseismology data from trench exposures across three active fault zones (Lomba do Meio, Lagoa do Capitão and Pico do Carvão faults) complement the information. Radiocarbon age constraints of paleoearthquakes suggest clustering of surface rupturing events. Slip rates deduced from paleoseismology analysis range from 0.10 to 0.40 cm/year and validate long-term slip rates obtained by neotectonic studies (using Pleistocene markers). The studied faults allowed a preliminary seismic hazard assessment: magnitudes of the largest paleoearthquakes, determined from slip per event range from Mw = 6.9 to 7.1, and maximum expected magnitudes, estimated from rupture length or rupture area, vary from Mw = 6.4 to 6.8. The former Mw estimates are in closer agreement with the magnitude of the major historic and instrumental seismic events in the archipelago, even though the used empirical relations between magnitude and rupture parameters may not be the most adequate due to the unique tectonic setting of Azores.http://www.annalsofgeophysics.eu/index.php/annals/article/view/3453Azoresneotectonicsactive faultingpaleoseismologyseismic hazard |
| spellingShingle | A. Brum da Silveira J. Madeira Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal) Annals of Geophysics Azores neotectonics active faulting paleoseismology seismic hazard |
| title | Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal) |
| title_full | Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal) |
| title_fullStr | Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal) |
| title_full_unstemmed | Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal) |
| title_short | Active tectonics and first paleoseismological results in Faial, Picoand S. Jorge islands (Azores, Portugal) |
| title_sort | active tectonics and first paleoseismological results in faial picoand s jorge islands azores portugal |
| topic | Azores neotectonics active faulting paleoseismology seismic hazard |
| url | http://www.annalsofgeophysics.eu/index.php/annals/article/view/3453 |
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