Abstract. Landslides triggered by strong earthquakes often j}VOr >xz
caused most of the global damage and most of all casualties zHdp'J"
related to the events, such as shown by the M = 7.7 Peru ~qqtFjlG^
earthquake in 1970, by the M = 7.6 El Salvador earthquake |E~X]_Y
in 2001 or by the M = 7.4 Khait (Tajikistan) earthquake .|aSGv E
in 1949. The obvious impact of a landslide on the population v
PGuEfz
is directly related to its movement. Yet, prediction of =TP>Y"
future failure potential and hence future risk to population I ! (yU
is necessary in order to avoid further catastrophes and involves bv+e'$U3
the analyses of the origin of seismic instability. The w- #0k.T
seismic landslide potential is mainly determined by the interaction Hug{9Hr3.
between the regional seismic hazard and local geological WuNu}Ibl}m
conditions. At a local scale, seismic factors interfering Bjo&
with geological conditions can produce site-specific ground TdE_\gEo/R
motions. The influence of such Site Effects on instability is IWWFl6$-
the principal topic of this paper, which is divided into two O#EBR<CuK
parts, A and B. The present Part A is concerned with the correlation <Z__Q
of field data with observed instability phenomena. E{6}'FG+A
Field data were obtained on mainly three landslide sites in vJCL
m/}*
the Northern Tien Shan Mountains in Kyrgyzstan, Central j |i6/Pk9J
Asia. Geophysical prospecting, earthquake recordings, geological m[bu(q z
observation, trenching and geotechnical tests were ZF
t^q /pw
the main investigation tools. The collected information gives 3LxJ}>]TO
an insight in the geological background of the slope failure X3-1)|g !z
and allows us to roughly infer failure mechanisms from field @s@
evidence. A detailed analysis of the susceptibility of a mechanism 8;'n. SC{
to specific geological conditions will be shown in Part *Qf }4a0
B. \\lC"Z#J`
1 Introduction
