TY - JOUR
T1 - Lithospheric Architecture of the Paranapanema Block and Adjacent Nuclei Using Multiple-Frequency P-Wave Seismic Tomography
AU - Affonso, G. M.P.C.
AU - Rocha, M. P.
AU - Costa, I. S.L.
AU - Assumpção, M.
AU - Fuck, R. A.
AU - Albuquerque, D. F.
AU - Portner, D. E.
AU - Rodríguez, E. E.
AU - Beck, S. L.
N1 - Funding Information:
We thank FAPESP (São Paulo State Research Foundation) for funding the “3‐Basins” project (grant 2013/24215‐6), which allowed installation of the XC network. We also thank Petrobras for funding initial infra‐structure of the Brazilian Seismographic Network (RSBR) and for current financial support (Project 2017/00161‐5), and the CPRM (Geological Survey of Brazil) for its maintenance in the last years. We thank CNPq for the INCT‐ET Project (465613/2014‐4) which allow financial support for the stations maintenance, and for the research fellowship grants 30.7151/2018‐2 (M. P. Rocha), 30.1284/2017‐2 (M. Assumpção), and 301065/2016‐0 (R. Fuck). We thank Professor Guust Nolet for providing the Seismic Tomography code, available at https://www.geoazur.fr/GLOBALSEIS/Soft.html . This study was financed in part by the Coordenação de Aperfeiçoamento de Pessoal em Nível Superior—Brasil (CAPES)—Finance Code 001. We would like to thank the two anonymous reviewers and the editors for their comments and suggestions, that improved the manuscript. We thank all staff and students that helped in the station installation.
Funding Information:
We thank FAPESP (S?o Paulo State Research Foundation) for funding the ?3-Basins? project (grant 2013/24215-6), which allowed installation of the XC network. We also thank Petrobras for funding initial infra-structure of the Brazilian Seismographic Network (RSBR) and for current financial support (Project 2017/00161-5), and the CPRM (Geological Survey of Brazil) for its maintenance in the last years. We thank CNPq for the INCT-ET Project (465613/2014-4) which allow financial support for the stations maintenance, and for the research fellowship grants 30.7151/2018-2 (M. P. Rocha), 30.1284/2017-2 (M. Assump??o), and 301065/2016-0 (R. Fuck). We thank Professor Guust Nolet for providing the Seismic Tomography code, available at https://www.geoazur.fr/GLOBALSEIS/Soft.html. This study was financed in part by the Coordena??o de Aperfei?oamento de Pessoal em N?vel Superior?Brasil (CAPES)?Finance Code 001. We would like to thank the two anonymous reviewers and the editors for their comments and suggestions, that improved the manuscript. We thank all staff and students that helped in the station installation.
Publisher Copyright:
© 2021. The Authors.
PY - 2021/4
Y1 - 2021/4
N2 - We present a new P-wave seismic tomographic model for the region of the Paraná Basin and surroundings using a multiple-frequency approach, providing better resolution than previous regional studies. We processed a total of 62,692 cross-correlation delays for P, PKIKP, PcP, and PP phases distributed among 1,081 events using six different central frequencies (0.03, 0.06, 0.13, 0.25, 0.50, and 1 Hz). We merged our data with a previous multiple-frequency study of the Amazonian Craton to cover regions outside of the study area, obtaining a total of 75,187 cross-correlation delays. The data used are from the stations of the Brazilian Seismographic Network, and mainly from a temporary network (XC network) installed exclusively to study the region. The basement of the Paraná Basin is represented as a NE-SW trending P-wave high-velocity anomaly, extending from the northern limit of the basin to the southwestern border of Brazil, consistent with previous reports. The limit between this block and the São Francisco Craton is characterized by decreased amplitude of the P-wave high-velocity anomaly. Synthetic tests show that a narrow boundary between these two blocks displays the same behavior. At the southeastern portion of this anomaly, decreasing amplitude is consistent with the limit of the Luiz Alves Craton, which was also corroborated by synthetic tests. The northern portion of the Rio Apa Block agrees with a previous tomographic model, confirming that it does not extend under the Pantanal Basin, however, in our model this structure does not extend as far south.
AB - We present a new P-wave seismic tomographic model for the region of the Paraná Basin and surroundings using a multiple-frequency approach, providing better resolution than previous regional studies. We processed a total of 62,692 cross-correlation delays for P, PKIKP, PcP, and PP phases distributed among 1,081 events using six different central frequencies (0.03, 0.06, 0.13, 0.25, 0.50, and 1 Hz). We merged our data with a previous multiple-frequency study of the Amazonian Craton to cover regions outside of the study area, obtaining a total of 75,187 cross-correlation delays. The data used are from the stations of the Brazilian Seismographic Network, and mainly from a temporary network (XC network) installed exclusively to study the region. The basement of the Paraná Basin is represented as a NE-SW trending P-wave high-velocity anomaly, extending from the northern limit of the basin to the southwestern border of Brazil, consistent with previous reports. The limit between this block and the São Francisco Craton is characterized by decreased amplitude of the P-wave high-velocity anomaly. Synthetic tests show that a narrow boundary between these two blocks displays the same behavior. At the southeastern portion of this anomaly, decreasing amplitude is consistent with the limit of the Luiz Alves Craton, which was also corroborated by synthetic tests. The northern portion of the Rio Apa Block agrees with a previous tomographic model, confirming that it does not extend under the Pantanal Basin, however, in our model this structure does not extend as far south.
UR - http://www.scopus.com/inward/record.url?scp=85104998162&partnerID=8YFLogxK
UR - http://www.scopus.com/inward/citedby.url?scp=85104998162&partnerID=8YFLogxK
U2 - 10.1029/2020JB021183
DO - 10.1029/2020JB021183
M3 - Article
AN - SCOPUS:85104998162
SN - 2169-9313
VL - 126
JO - Journal of Geophysical Research: Solid Earth
JF - Journal of Geophysical Research: Solid Earth
IS - 4
M1 - e2020JB021183
ER -