TY - JOUR
T1 - Marginal Detachment Zones
T2 - The Fracture Factories of Ice Shelves?
AU - Miele, Chris
AU - Bartholomaus, Timothy C.
AU - Enderlin, Ellyn M.
N1 - Publisher Copyright:
© 2023. American Geophysical Union. All Rights Reserved.
PY - 2023/6
Y1 - 2023/6
N2 - Along the lateral margins of floating ice shelves in Greenland and Antarctica, ice flow past confining margins and pinning points is often accompanied by extensive rifting. Rifts in zones of marginal decoupling (“detachment zones”) typically propagate inward from the margins and result in many of Earth's largest calving events. Velocity maps of detachment zones indicate that flow through these regions is spatially transitioning from confined to unconfined ice shelf flow. We employ the software package icepack to demonstrate that longitudinally decreasing marginal resistance reproduces observed transitions in flow regime, and we show that these spatial transitions are accompanied by near-margin tension sufficient to explain full-thickness rifts. Thus, we suggest that zones of progressive decoupling are a primary control on ice shelf calving. The steadiness of detachment zone positions may be a good indicator of ice shelf vulnerability, with migratory or thinning detachment zones indicating shelves at risk of dynamic speedup and increased fracture.
AB - Along the lateral margins of floating ice shelves in Greenland and Antarctica, ice flow past confining margins and pinning points is often accompanied by extensive rifting. Rifts in zones of marginal decoupling (“detachment zones”) typically propagate inward from the margins and result in many of Earth's largest calving events. Velocity maps of detachment zones indicate that flow through these regions is spatially transitioning from confined to unconfined ice shelf flow. We employ the software package icepack to demonstrate that longitudinally decreasing marginal resistance reproduces observed transitions in flow regime, and we show that these spatial transitions are accompanied by near-margin tension sufficient to explain full-thickness rifts. Thus, we suggest that zones of progressive decoupling are a primary control on ice shelf calving. The steadiness of detachment zone positions may be a good indicator of ice shelf vulnerability, with migratory or thinning detachment zones indicating shelves at risk of dynamic speedup and increased fracture.
KW - Antarctica
KW - Greenland
KW - ice shelves
KW - iceberg calving
UR - http://www.scopus.com/inward/record.url?scp=85163299096&partnerID=8YFLogxK
U2 - 10.1029/2022JF006959
DO - 10.1029/2022JF006959
M3 - Article
AN - SCOPUS:85163299096
SN - 2169-9003
VL - 128
JO - Journal of Geophysical Research: Earth Surface
JF - Journal of Geophysical Research: Earth Surface
IS - 6
M1 - e2022JF006959
ER -