TY - JOUR
T1 - Deep and rapid thermo-mechanical erosion by a small-volume lava flow
AU - Gallant, E.
AU - Deng, F.
AU - Connor, C. B.
AU - Dixon, T. H.
AU - Xie, S.
AU - Saballos, J. A.
AU - Gutiérrez, C.
AU - Myhre, D.
AU - Connor, L.
AU - Zayac, J.
AU - LaFemina, P.
AU - Charbonnier, S.
AU - Richardson, J.
AU - Malservisi, R.
AU - Thompson, G.
N1 - Funding Information:
Funding for field work was provided by NSF EAR 1620977 : Geochemical and Geophysical Observations of the 2015 Eruption of Volcan Momotombo, Nicaragua, awarded to PL, CC, and others. Deployment of the TRI was partially funded by NSF RAPID grant EAR 1546924 to THD and SC. Field support was provided by many staff members at INETER. We thank the German Aerospace Center (DLR) for providing TanDEM-X SAR data. Equipment logistics were eased by the efforts of Denis Voytenko, Milton Ordonez, and Anderson at the Servicio Geológico Colombiano. The manuscript's clarity was improved by feedback from Jen Bright and Christopher Sant. Pam Wayne and Jose Rincon were crucial in facilitating this feedback. We thank Heather Handley (editor) and reviewers Jamie Farquharson and David Williams for their quick and thoughtful feedback.
Funding Information:
Funding for field work was provided by NSF EAR 1620977: Geochemical and Geophysical Observations of the 2015 Eruption of Volcan Momotombo, Nicaragua, awarded to PL, CC, and others. Deployment of the TRI was partially funded by NSF RAPID grant EAR 1546924 to THD and SC. Field support was provided by many staff members at INETER. We thank the German Aerospace Center (DLR) for providing TanDEM-X SAR data. Equipment logistics were eased by the efforts of Denis Voytenko, Milton Ordonez, and Anderson at the Servicio Geol?gico Colombiano. The manuscript's clarity was improved by feedback from Jen Bright and Christopher Sant. Pam Wayne and Jose Rincon were crucial in facilitating this feedback. We thank Heather Handley (editor) and reviewers Jamie Farquharson and David Williams for their quick and thoughtful feedback.
Publisher Copyright:
© 2020 Elsevier B.V.
PY - 2020/5/1
Y1 - 2020/5/1
N2 - We document remarkably efficient thermo-mechanical erosion by a small-volume lava flow. Downcutting by a basaltic-andesite lava flow on the steep-sided Momotombo volcano, Nicaragua, occurred at 100 times the rate commonly reported for thermal erosion in lava flow fields, even though this flow was small-volume (0.02 km3) and effused at a low rate for <1 week. The lava flow incised into the pyroclastic substrate up to 30 m, with erosion depth controlled primarily by thermal reduction of substrate hardness. We show that incision depth decreases, approximately exponentially, with distance along the flow path, until erosion stopped and the flow became constructional. This transition occurs 650 m from the vent on a slope averaging a 32∘ incline. Results indicate that syn-eruptive erosion is an important morphological process on some steep-sided volcanoes that are predominantly composed of layered pyroclasts. Rapid erosion and incision increased flow run-out for the 1905 flow, which in turn directed the flow and run-out of the 2015 lava flow. Mapping and understanding these features is critical for improving lava flow hazard assessments and provides insight into the construction and growth of composite cones.
AB - We document remarkably efficient thermo-mechanical erosion by a small-volume lava flow. Downcutting by a basaltic-andesite lava flow on the steep-sided Momotombo volcano, Nicaragua, occurred at 100 times the rate commonly reported for thermal erosion in lava flow fields, even though this flow was small-volume (0.02 km3) and effused at a low rate for <1 week. The lava flow incised into the pyroclastic substrate up to 30 m, with erosion depth controlled primarily by thermal reduction of substrate hardness. We show that incision depth decreases, approximately exponentially, with distance along the flow path, until erosion stopped and the flow became constructional. This transition occurs 650 m from the vent on a slope averaging a 32∘ incline. Results indicate that syn-eruptive erosion is an important morphological process on some steep-sided volcanoes that are predominantly composed of layered pyroclasts. Rapid erosion and incision increased flow run-out for the 1905 flow, which in turn directed the flow and run-out of the 2015 lava flow. Mapping and understanding these features is critical for improving lava flow hazard assessments and provides insight into the construction and growth of composite cones.
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U2 - 10.1016/j.epsl.2020.116163
DO - 10.1016/j.epsl.2020.116163
M3 - Article
AN - SCOPUS:85081118418
SN - 0012-821X
VL - 537
JO - Earth and Planetary Science Letters
JF - Earth and Planetary Science Letters
M1 - 116163
ER -