On predictability of slip, rupture geometry, and speed of the 2025 M7.8 Mandalay, Myanmar, earthquake
Abstract
The 2025 M 7.8 Mandalay earthquake ruptured ~480 km of the Sagaing Fault, producing one of the longest strike-slip events documented and impacting a vulnerable region. Here we combine remote sensing observations and numerical modeling to show that the subsurface fault geometry and slip distribution could be anticipated from pre-event observations. Along-strike variations in coseismic and interseismic deformation reveal a helix-shaped fault geometry. The average coseismic slip equals or exceeds the interseismic slip deficit, consistent with a minimally slip-predictable model. We generate an ensemble of 3D dynamic rupture models, constrained by the best-fit static slip model, then discriminate among them using independent space-geodetic, seismic, and near-field video observations. The preferred scenario begins bilaterally, then transitions to unilateral southward supershear propagation at depth, while shallow rupture remains subshear. These dynamics are shaped by localized stress heterogeneity and low fracture energy, characteristic of a structurally mature fault zone. Our approach can inform rupture scenarios in understudied regions.
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BibTeX
@article{ulrich2026predictability,
title = {{On predictability of slip, rupture geometry, and speed of the 2025 M7.8 Mandalay, Myanmar, earthquake}},
author = {Thomas Ulrich and Xiaoyu Zou and Mathilde Marchandon and Nico Schliwa and Fengzhou Tan and Alice-Agnes Gabriel and Wenyuan Fan and Peter Shearer and Myo Thant and Tha Zin Htet Tin and Eric O. Lindsey and Yuri Fialko},
journal = {Nature Communications},
year = {2026},
month = oct,
doi = {10.1038/s41467-026-77203-x},
url = {https://www.nature.com/articles/s41467-026-77203-x},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - On predictability of slip, rupture geometry, and speed of the 2025 M7.8 Mandalay, Myanmar, earthquake
AU - Thomas Ulrich
AU - Xiaoyu Zou
AU - Mathilde Marchandon
AU - Nico Schliwa
AU - Fengzhou Tan
AU - Alice-Agnes Gabriel
AU - Wenyuan Fan
AU - Peter Shearer
AU - Myo Thant
AU - Tha Zin Htet Tin
AU - Eric O. Lindsey
AU - Yuri Fialko
PY - 2026
DA - 2026/10/14
JO - Nature Communications
DO - 10.1038/s41467-026-77203-x
UR - https://www.nature.com/articles/s41467-026-77203-x
AB - The 2025 M 7.8 Mandalay earthquake ruptured ~480 km of the Sagaing Fault, producing one of the longest strike-slip events documented and impacting a vulnerable region. Here we combine remote sensing observations and numerical modeling to show that the subsurface fault geometry and slip distribution could be anticipated from pre-event observations. Along-strike variations in coseismic and interseismic deformation reveal a helix-shaped fault geometry. The average coseismic slip equals or exceeds the interseismic slip deficit, consistent with a minimally slip-predictable model. We generate an ensemble of 3D dynamic rupture models, constrained by the best-fit static slip model, then discriminate among them using independent space-geodetic, seismic, and near-field video observations. The preferred scenario begins bilaterally, then transitions to unilateral southward supershear propagation at depth, while shallow rupture remains subshear. These dynamics are shaped by localized stress heterogeneity and low fracture energy, characteristic of a structurally mature fault zone. Our approach can inform rupture scenarios in understudied regions.
SN - 2041-1723
ER -