Journal articles
Preservation of contrasting geothermal gradients across the Caribbean-North America plate boundary (Motagua Fault, Guatemala)
Abstract : Strike-slip plate boundaries juxtapose crustal blocks that may have different geodynamic origins and therefore different thermal structures. Thermo-kinematic modeling of this type of strike-slip plate boundary predicts an asymmetric signature in the low-temperature thermochronologic record across the fault. Age-elevation profiles of zircon (U-Th)/He ages across the Motagua Fault, a 500 km long segment of the transform boundary between the North American and Caribbean plates, document a sharp cooling age discontinuity across the fault. This discontinuity could be interpreted as a difference in denudation history on each side of the fault. However, a low-relief Miocene erosional surface extends across the fault; this surface has been uplifted and incised and provides a geomorphic argument against differential denudation across the fault. By integrating magmatic, volcanic, and heat flow data, age-elevation profiles, and thermo-kinematic modeling, we propose that large horizontal displacement along the Motagua Fault has offset a persistent geothermal asymmetry across the fault and explains both the age discontinuities and the age-elevation patterns. This study illustrates how thermochronology can be used to detect large strike-slip displacements and more generally opens new perspectives in understanding the impact of nonuniform thermal structures on thermochronologic results.
Cited literature [87 references]
https://hal-insu.archives-ouvertes.fr/insu-00864297
Contributor : Adminhal Univbrestbu Connect in order to contact the contributor
Submitted on : Sunday, March 23, 2014 - 7:00:05 AM
Last modification on : Tuesday, October 19, 2021 - 7:01:17 PM
Long-term archiving on: : Friday, April 7, 2017 - 12:50:45 AM
Contributor : Adminhal Univbrestbu Connect in order to contact the contributor
Submitted on : Sunday, March 23, 2014 - 7:00:05 AM
Last modification on : Tuesday, October 19, 2021 - 7:01:17 PM
Long-term archiving on: : Friday, April 7, 2017 - 12:50:45 AM
File
tectonics-Simon-labric.pdf
Publisher files allowed on an open archive