Produção Nacional
Revisado por pares
Seismicity Migration Induced by the Açu Reservoir, Northeast Brazil, and Implications for Fault Hydraulic Variability
2018; Seismological Society of America; Volume: 108; Issue: 5B Linguagem: Inglês
10.1785/0120170372
ISSN1943-3573
AutoresP. A. R. Ferreira, Joaquim Mendes Ferreira, Aderson F. do Nascimento, Francisco H.R. Bezerra, H. C. Lima Neto, E. A. Menezes,
Tópico(s)Seismic Waves and Analysis
ResumoResearch Article| September 25, 2018 Seismicity Migration Induced by the Açu Reservoir, Northeast Brazil, and Implications for Fault Hydraulic Variability Pedro A. R. Ferreira; Pedro A. R. Ferreira aPrograma de Pós Graduação em Geodinâmica e Geofísica, Universidade Federal do Rio G. do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil Search for other works by this author on: GSW Google Scholar Joaquim M. Ferreira; Joaquim M. Ferreira bDepartamento de Geofísica, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil, aderson@geofisica.ufrn.br Search for other works by this author on: GSW Google Scholar Aderson F. do Nascimento; Aderson F. do Nascimento bDepartamento de Geofísica, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil, aderson@geofisica.ufrn.breAlso at INCT/GP—Instituto Nacional de Ciência e Tecnologia em Geofísica do Petróleo, CNPq, Brazil. Search for other works by this author on: GSW Google Scholar Francisco H. R. Bezerra; Francisco H. R. Bezerra cDepartamento de Geologia, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil Search for other works by this author on: GSW Google Scholar Heleno C. Lima Neto; Heleno C. Lima Neto dUniversidade Potiguar, Escola de Engenharias e Ciências Exatas, Natal, RN 59054‐180 Brazil Search for other works by this author on: GSW Google Scholar Eduardo A. S. Menezes Eduardo A. S. Menezes bDepartamento de Geofísica, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil, aderson@geofisica.ufrn.br Search for other works by this author on: GSW Google Scholar Author and Article Information Pedro A. R. Ferreira aPrograma de Pós Graduação em Geodinâmica e Geofísica, Universidade Federal do Rio G. do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil Joaquim M. Ferreira bDepartamento de Geofísica, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil, aderson@geofisica.ufrn.br Aderson F. do Nascimento bDepartamento de Geofísica, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil, aderson@geofisica.ufrn.breAlso at INCT/GP—Instituto Nacional de Ciência e Tecnologia em Geofísica do Petróleo, CNPq, Brazil. Francisco H. R. Bezerra cDepartamento de Geologia, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil Heleno C. Lima Neto dUniversidade Potiguar, Escola de Engenharias e Ciências Exatas, Natal, RN 59054‐180 Brazil Eduardo A. S. Menezes bDepartamento de Geofísica, Universidade Federal do Rio Grande do Norte, Campus Universitário, Natal, RN 59078‐970 Brazil, aderson@geofisica.ufrn.br Publisher: Seismological Society of America First Online: 25 Sep 2018 Online Issn: 1943-3573 Print Issn: 0037-1106 © Seismological Society of America Bulletin of the Seismological Society of America (2018) 108 (5B): 3107–3118. https://doi.org/10.1785/0120170372 Article history First Online: 25 Sep 2018 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Pedro A. R. Ferreira, Joaquim M. Ferreira, Aderson F. do Nascimento, Francisco H. R. Bezerra, Heleno C. Lima Neto, Eduardo A. S. Menezes; Seismicity Migration Induced by the Açu Reservoir, Northeast Brazil, and Implications for Fault Hydraulic Variability. Bulletin of the Seismological Society of America 2018;; 108 (5B): 3107–3118. doi: https://doi.org/10.1785/0120170372 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyBulletin of the Seismological Society of America Search Advanced Search Abstract Seismic activity beneath the Açu reservoir, northeast Brazil, is considered a classic, clear example of reservoir‐induced seismicity (RIS) and has been investigated during the last two decades. After a quiescent period from April 1997 to June 2012, recent seismic activity was recorded by a seismic network deployed in the area during the seismic sequence, which lasted from July 2012 to April 2013. We located 50 seismic events from this recent sequence with Mw ranging from 0.1 to 1.4 and obtained well‐constrained relative locations and a composite focal mechanism for 35 of these events. The earthquakes occurred mainly beneath the lake at a depth of 3.5 km in a subvertical east‐northeast‐striking fault composed of two clusters ∼250 m apart, defining a fault zone 150 m wide and ∼1.5 km long, and were associated with the reactivation of the basement on a new fault cross cutting the main northeast–southwest‐striking mylonitic structure. We estimate hydraulic transport properties within seismogenic faults. Depth‐averaged and within‐fault‐plane permeabilities are 10−15 and 10−16 m2, respectively, near the lower bounds of values found in the literature. We observe the seismicity at 3–4 km depth in the 2012–2013 sequence period; this was likely related to the long‐term decrease in the water level. As the water level fell steadily because of drought in the region since 2011, the pore pressure due to diffusion (and the undrained response at a fraction of the water load) decreased, and the average load pressure decreased even more, leading to failure. Thus, the east‐northeast‐striking fault remained active until the pore pressure became less than the average load. This interplay between water level variation and pore pressure could explain the episodic behavior of the seismicity in a different active fault region in the 2012–2013 period. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.
Referência(s)