@article{fdi:010071279,
  title = {{S}ustained out-of-sequence shortening along a tectonically active segment of the {M}ain {B}oundary thrust : the {D}hauladhar {R}ange in the northwestern {H}imalaya},
  author = {{T}hiede, {R}. and {R}obert, {X}avier and {S}tubner, {K}. and {D}ey, {S}. and {F}aruhn, {J}.},
  editor = {},
  language = {{ENG}},
  abstract = {{C}ompeting hypotheses suggest that {H}imalayan topography is sustained and the plate convergence is accommodated either solely along the basal decollement, the {M}ain {H}imalayan thrust ({MHT}), or more broadly, across multiple thrust faults. {I}n the past, structural, geomorphic, and geodetic data of the {N}epalese {H}imalaya have been used to constrain the geometry of the {MHT} and its shallow frontal thrust fault, known as {M}ain {F}rontal thrust ({MFT}). {T}he {MHT} flattens at depth and connects to a hinterland mid-crustal, steeper thrust ramp, located similar to 100 km north of the deformation front. {T}here, the present-day convergence across the {H}imalaya is mostly accommodated by slip along the {MFT}. {D}espite a general agreement that in {N}epal most of the shortening is accommodated along the {MHT}, some researchers have suggested the occurrence of persistent out-of-sequence shortening on interior faults near the {M}ain {C}entral thrust ({MCT}). {A}long the northwest {H}imalaya, in contrast, some of these characteristics of central {N}epal are missing, suggesting along-strike variation of wedge deformation and {MHT} fault geometry. {H}ere we present new field observations and seven zircon ({U}-{T}h)/{H}e ({ZH}e) cooling ages combined with existing low-temperature data sets. {I}n agreement with our previous findings, we suggest that the transect of cooling age patterns across the frontal {D}hauladhar {R}ange reveals that the {M}ain {B}oundary thrust ({MBT}) is a primary fault, which has uplifted and sustained this spectacular mountain front since at least the late {M}iocene. {O}ur results suggest that the {MBT} forms an similar to 40-km-long fault ramp before it soles into the {MHT}, and motion along it has exhumed rocks from depth of similar to 8-10 km. {N}ew three-dimensional thermokinematic modeling (using {P}ecube finite-element code) reveals that the observed {ZH}e and apatite fission track cooling ages can only be explained by sustained mean {MBT} slip rates between similar to 2.6 and 3.5 mm a(-1) since at least 8 {M}a, which corresponds to a horizontal shortening rate of similar to 1.7-2.4 mm a(-1). {W}e propose that the {MBT} is active today, despite a lack of definitive field or seismogenic evidence, and continues to accommodate crustal shorting by out-of-sequence faulting. {A}ssuming that present-day geodetic shorting rates (similar to 14 +/- 2 mm a(-1)) across the northwest {H}imalaya have been sustained over geologic time scales, this implies that the {MBT} accommodated similar to 15% of the total {H}imalayan convergence since its onset. {F}urthermore, our modeling results imply that the {MHT} is missing a hinterland mid-crustal ramp further north.},
  keywords = {{INDE} ; {HIMALAYA} ; {DHAULADHAR}},
  booktitle = {},
  journal = {{L}ithosphere},
  volume = {9},
  numero = {5},
  pages = {715--725},
  ISSN = {1941-8264},
  year = {2017},
  DOI = {10.1130/l630.1},
  URL = {https://www.documentation.ird.fr/hor/fdi:010071279},
}