TY - JOUR

T1 - Lithospheric delamination as the driving mechanism of intermediate-depth seismicity in the Bucaramanga Nest, Colombia

AU - Pérez-Forero, Diego

AU - Koulakov, Ivan

AU - Vargas, Carlos A

AU - Gerya, Taras

AU - Al Arifi, Nassir

N1 - The authors thank the Deanship of Scientific Research, King Saud University for funding through Vice Deanship of Scientific Research Chairs. IK is supported by the RSF grant #20-17-00075. TG is supported by SNF Research Grant 200021_192296 and by ILP Task Force “Bio-geodynamics of the Lithosphere”. © 2023. The Author(s).

PY - 2023/12

Y1 - 2023/12

N2 - The Bucaramanga nest (BN) is an area of exceptionally strong intermediate-depth seismicity localized in a narrow zone at 150-170 km depth beneath the continental plate in Colombia. To explain the very unusual mantle seismicity cluster in this area, we built a seismic velocity model in the vicinity of BN with the use of local earthquake tomography and developed a numerical hydromechanical model. Our seismic model shows a strong high-velocity anomaly at 130-167 km coinciding with the BN seismicity. The relocated seismicity can be separated in two clusters. We propose that the upper BN cluster at ~ 130 km depth is attributed to dehydration embrittlement, whereas the lower BN cluster at ~ 150 km depth coinciding with the high-velocity body is caused by lithospheric delamination, creating a "drip" that falls down over the subducting oceanic plate, enhancing fluid release from the slab, potentially increasing seismicity.

AB - The Bucaramanga nest (BN) is an area of exceptionally strong intermediate-depth seismicity localized in a narrow zone at 150-170 km depth beneath the continental plate in Colombia. To explain the very unusual mantle seismicity cluster in this area, we built a seismic velocity model in the vicinity of BN with the use of local earthquake tomography and developed a numerical hydromechanical model. Our seismic model shows a strong high-velocity anomaly at 130-167 km coinciding with the BN seismicity. The relocated seismicity can be separated in two clusters. We propose that the upper BN cluster at ~ 130 km depth is attributed to dehydration embrittlement, whereas the lower BN cluster at ~ 150 km depth coinciding with the high-velocity body is caused by lithospheric delamination, creating a "drip" that falls down over the subducting oceanic plate, enhancing fluid release from the slab, potentially increasing seismicity.

UR - https://www.scopus.com/record/display.uri?eid=2-s2.0-85180637697&origin=inward&txGid=0ae23b999e0644730318dd73080393b2

U2 - 10.1038/s41598-023-50159-4

DO - 10.1038/s41598-023-50159-4

M3 - Article

C2 - 38155214

VL - 13

JO - Scientific Reports

JF - Scientific Reports

SN - 2045-2322

IS - 1

M1 - 23084

ER -