Overlapping slabs: Untangling subduction in NW South America through finite-frequency teleseismic tomography

Meng Sun; Maximiliano J. Bezada; John Cornthwaite; German A. Prieto; Fenglin Niu; Alan Levander

doi:10.1016/j.epsl.2021.117253

Overlapping slabs: Untangling subduction in NW South America through finite-frequency teleseismic tomography

Meng Sun, Maximiliano J. Bezada, John Cornthwaite, German A. Prieto, Fenglin Niu, Alan Levander

Earth and Environmental Sciences-Twin Cities

Research output: Contribution to journal › Article › peer-review

20 Scopus citations

Abstract

Both the Caribbean and Nazca plates subduct beneath northwestern South America. The configuration of the two subducted slabs and the nature of any interaction between them has long been a matter of debate. Based on the location of intermediate-depth seismicity and active and extinct volcanism, as well as on seismic imaging, several different tectonic scenarios have been proposed. In this paper, we use teleseismic data recorded by the Colombian National Network and the temporary CARMA array in Venezuela and Colombia to produce a finite-frequency tomography model for the region. Our results show several distinct subduction segments. Through synthetic tests, we show that our results require a zone of overlap between Nazca and Caribbean subduction north of the “Caldas Tear” as has been proposed by previous studies. Additionally, we find that the Bucaramanga Nest occurs within the Caribbean Plate and coincides with bending of the slab in two planes, where both the strike and the dip of the slab change. We infer that elevated stresses are an important factor in producing the very high rates of seismicity in the nest.

Original language	English (US)
Article number	117253
Journal	Earth and Planetary Science Letters
Volume	577
DOIs	https://doi.org/10.1016/j.epsl.2021.117253
State	Published - Jan 1 2022

Bibliographical note

Funding Information:
We thank the Colombian Geological Service and the Venezuelan Foundation for Seismological research for providing data from their permanent and temporary stations and for their operation of the CARMA seismic array. The US seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center. The facilities of the IRIS Consortium are supported by the National Science Foundation 's Seismological Facilities for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1851048 . This research was partly supported by the National Science Foundation under Grant No. EAR-1459047 . We thank two anonymous reviewers who provided valuable feedback that helped improve the manuscript.

Funding Information:
We thank the Colombian Geological Service and the Venezuelan Foundation for Seismological research for providing data from their permanent and temporary stations and for their operation of the CARMA seismic array. The US seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center. The facilities of the IRIS Consortium are supported by the National Science Foundation's Seismological Facilities for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1851048. This research was partly supported by the National Science Foundation under Grant No. EAR-1459047. We thank two anonymous reviewers who provided valuable feedback that helped improve the manuscript.

Publisher Copyright:
© 2021 Elsevier B.V.

Keywords

Caribbean
Nazca
flat slab
northern Andes
northern South America
subduction

Publisher link

10.1016/j.epsl.2021.117253

Find It

Find It at U of M Libraries

Cite this

@article{8451af796c634e638d6aa075626ac7e8,

title = "Overlapping slabs: Untangling subduction in NW South America through finite-frequency teleseismic tomography",

abstract = "Both the Caribbean and Nazca plates subduct beneath northwestern South America. The configuration of the two subducted slabs and the nature of any interaction between them has long been a matter of debate. Based on the location of intermediate-depth seismicity and active and extinct volcanism, as well as on seismic imaging, several different tectonic scenarios have been proposed. In this paper, we use teleseismic data recorded by the Colombian National Network and the temporary CARMA array in Venezuela and Colombia to produce a finite-frequency tomography model for the region. Our results show several distinct subduction segments. Through synthetic tests, we show that our results require a zone of overlap between Nazca and Caribbean subduction north of the “Caldas Tear” as has been proposed by previous studies. Additionally, we find that the Bucaramanga Nest occurs within the Caribbean Plate and coincides with bending of the slab in two planes, where both the strike and the dip of the slab change. We infer that elevated stresses are an important factor in producing the very high rates of seismicity in the nest.",

keywords = "Caribbean, Nazca, flat slab, northern Andes, northern South America, subduction",

author = "Meng Sun and Bezada, {Maximiliano J.} and John Cornthwaite and Prieto, {German A.} and Fenglin Niu and Alan Levander",

note = "Funding Information: We thank the Colombian Geological Service and the Venezuelan Foundation for Seismological research for providing data from their permanent and temporary stations and for their operation of the CARMA seismic array. The US seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center. The facilities of the IRIS Consortium are supported by the National Science Foundation 's Seismological Facilities for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1851048 . This research was partly supported by the National Science Foundation under Grant No. EAR-1459047 . We thank two anonymous reviewers who provided valuable feedback that helped improve the manuscript. Funding Information: We thank the Colombian Geological Service and the Venezuelan Foundation for Seismological research for providing data from their permanent and temporary stations and for their operation of the CARMA seismic array. The US seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center. The facilities of the IRIS Consortium are supported by the National Science Foundation's Seismological Facilities for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1851048. This research was partly supported by the National Science Foundation under Grant No. EAR-1459047. We thank two anonymous reviewers who provided valuable feedback that helped improve the manuscript. Publisher Copyright: {\textcopyright} 2021 Elsevier B.V.",

year = "2022",

month = jan,

day = "1",

doi = "10.1016/j.epsl.2021.117253",

language = "English (US)",

volume = "577",

journal = "Earth and Planetary Science Letters",

issn = "0012-821X",

publisher = "Elsevier B.V.",

}

TY - JOUR

T1 - Overlapping slabs

T2 - Untangling subduction in NW South America through finite-frequency teleseismic tomography

AU - Sun, Meng

AU - Bezada, Maximiliano J.

AU - Cornthwaite, John

AU - Prieto, German A.

AU - Niu, Fenglin

AU - Levander, Alan

N1 - Funding Information: We thank the Colombian Geological Service and the Venezuelan Foundation for Seismological research for providing data from their permanent and temporary stations and for their operation of the CARMA seismic array. The US seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center. The facilities of the IRIS Consortium are supported by the National Science Foundation 's Seismological Facilities for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1851048 . This research was partly supported by the National Science Foundation under Grant No. EAR-1459047 . We thank two anonymous reviewers who provided valuable feedback that helped improve the manuscript. Funding Information: We thank the Colombian Geological Service and the Venezuelan Foundation for Seismological research for providing data from their permanent and temporary stations and for their operation of the CARMA seismic array. The US seismic instruments were provided by the Incorporated Research Institutions for Seismology (IRIS) through the PASSCAL Instrument Center. The facilities of the IRIS Consortium are supported by the National Science Foundation's Seismological Facilities for the Advancement of Geoscience (SAGE) Award under Cooperative Support Agreement EAR-1851048. This research was partly supported by the National Science Foundation under Grant No. EAR-1459047. We thank two anonymous reviewers who provided valuable feedback that helped improve the manuscript. Publisher Copyright: © 2021 Elsevier B.V.

PY - 2022/1/1

Y1 - 2022/1/1

N2 - Both the Caribbean and Nazca plates subduct beneath northwestern South America. The configuration of the two subducted slabs and the nature of any interaction between them has long been a matter of debate. Based on the location of intermediate-depth seismicity and active and extinct volcanism, as well as on seismic imaging, several different tectonic scenarios have been proposed. In this paper, we use teleseismic data recorded by the Colombian National Network and the temporary CARMA array in Venezuela and Colombia to produce a finite-frequency tomography model for the region. Our results show several distinct subduction segments. Through synthetic tests, we show that our results require a zone of overlap between Nazca and Caribbean subduction north of the “Caldas Tear” as has been proposed by previous studies. Additionally, we find that the Bucaramanga Nest occurs within the Caribbean Plate and coincides with bending of the slab in two planes, where both the strike and the dip of the slab change. We infer that elevated stresses are an important factor in producing the very high rates of seismicity in the nest.

AB - Both the Caribbean and Nazca plates subduct beneath northwestern South America. The configuration of the two subducted slabs and the nature of any interaction between them has long been a matter of debate. Based on the location of intermediate-depth seismicity and active and extinct volcanism, as well as on seismic imaging, several different tectonic scenarios have been proposed. In this paper, we use teleseismic data recorded by the Colombian National Network and the temporary CARMA array in Venezuela and Colombia to produce a finite-frequency tomography model for the region. Our results show several distinct subduction segments. Through synthetic tests, we show that our results require a zone of overlap between Nazca and Caribbean subduction north of the “Caldas Tear” as has been proposed by previous studies. Additionally, we find that the Bucaramanga Nest occurs within the Caribbean Plate and coincides with bending of the slab in two planes, where both the strike and the dip of the slab change. We infer that elevated stresses are an important factor in producing the very high rates of seismicity in the nest.

KW - Caribbean

KW - Nazca

KW - flat slab

KW - northern Andes

KW - northern South America

KW - subduction

UR - http://www.scopus.com/inward/record.url?scp=85117908053&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=85117908053&partnerID=8YFLogxK

U2 - 10.1016/j.epsl.2021.117253

DO - 10.1016/j.epsl.2021.117253

M3 - Article

AN - SCOPUS:85117908053

SN - 0012-821X

VL - 577

JO - Earth and Planetary Science Letters

JF - Earth and Planetary Science Letters

M1 - 117253

ER -

Overlapping slabs: Untangling subduction in NW South America through finite-frequency teleseismic tomography

Abstract

Bibliographical note

Keywords

Publisher link

Find It

Other files and links

Fingerprint

Cite this