@article{fdi:010077294,
  title = {{L}ower crustal heterogeneity beneath the {N}orthern {T}ibetan {P}lateau constrained by {GPS} measurements following the 2001 {M}w7.8 {K}okoxili earthquake},
  author = {{L}iu, {S}. {Z}. and {X}u, {X}. {W}. and {K}linger, {Y}. and {N}ocquet, {J}ean-{M}athieu and {C}hen, {G}. {H}. and {Y}u, {G}. {H}. and {J}onsson, {S}.},
  editor = {},
  language = {{ENG}},
  abstract = {{W}e use {GPS} measurements across the {X}idatan segment of the {K}unlun fault in the {T}ibetan {P}lateau to investigate the surface deformation following the 2001 {M}w 7.8 {K}okoxili earthquake. {W}e find significant postseismic deformation during the period 2007-2015, characterized by an asymmetric shear across the 2001 rupture, with average velocities reaching similar to 10 mm/year about 30-45 km south of the coseismic rupture. {W}e also find that the postseismic transients diffused away from the coseismic rupture through time, with a shift of the maximum transient rates from similar to 20-30 km south of the rupture in 2001-2002 to similar to 30-45 km in 2007-2015. {V}iscoelastic relaxation is the dominant physical process during the period 2007-2015. {T}he estimated effective viscosity of the lower crust beneath the {S}ongpan-{G}anzi terrane is 2 x 10(18)-3 x 10(18) {P}a s from the 2001-2002 data, and it has increased to similar to 2 x 10(19) {P}a s for the period 6 to 14 years after the event. {T}he large asymmetry in the postseismic deformation field indicates a laterally heterogeneous lower crust beneath the northern {T}ibetan {P}lateau. {V}iscoelastic relaxation models show that the viscosity of the lower crust beneath the {Q}aidam basin is similar to 2 and similar to 4 times larger than the viscosity of the lower crust beneath the {S}ongpan-{G}anzi terrane in 2001-2002 and 2007-2015, respectively. {B}ased on these data and results from previous studies, we postulate that the {K}unlun fault itself is not the unique rheological boundary and that additional domains with viscosity increasing from the {Q}iangtang terrane to the {Q}aidam basin appear to be required. {P}lain {L}anguage {S}ummary {V}iscoelastic relaxation of earthquake-induced deviatoric stress change can last for several decades. {I}n 2001, the {M}w7.8 {K}okoxili earthquake occurred along the {K}unlun fault in the northern {T}ibetan {P}lateau. {GPS} measurements in the first two decades after the 2001 event show (1) that postseismic transients diffused away from the fault and (2) that postseismic transients are asymmetric across the coseismic rupture. {W}e find that lower crustal viscosity heterogeneity leads to the observed asymmetric deformation. {A}lthough geodetic data constraints with better spatial and temporal coverage are needed, we find that lower crustal viscosity may exhibit northward stepwise increase across the {J}insha {R}iver suture, {K}unlun fault, and the southern margin of the {Q}aidam basin. {O}ur findings provide new constraints on the lithospheric structure and tectonic deformation in the northern {T}ibetan {P}lateau.},
  keywords = {{TIBET} ; {KOKOXILI}},
  booktitle = {},
  journal = {{J}ournal of {G}eophysical {R}esearch : {S}olid {E}arth},
  volume = {124},
  numero = {11},
  pages = {11992--12022},
  ISSN = {2169-9313},
  year = {2019},
  DOI = {10.1029/2019jb017732},
  URL = {https://www.documentation.ird.fr/hor/fdi:010077294},
}