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Chapter 1
Introduction

Majority of mud houses in the neighbouring villages also suffered heavy damage.
In the Jabalpur district 371 villages were affected and out of these, 22 villages
were severely damaged; 22 781 families and a population of 141 165 were
affected. In the affected villages more than 22 176 houses were partially damaged
and 2135 houses were mostly destroyed. Most of houses which suffered partial to
complete collapse in the meizoseismal area were made from thick mud walls
with roof constructed of tiles and supported ona bamboo grid.

GEOTECHNICAL OBSERVATIONS

No prominent ground deformation associated with faulting, liquefaction and
landslides were observed. However, some minor cracking on the ground surface
was observed at several places, e.g., Kosamghat, Gauraiyaghat, Kogwan, Adhar-
tal, etc.

Most of the old Jabalpur city is located in a valley characterized by a thick allu-
viuam soil deposit whereas new population centres have developed in neigh-
bouring hilly areas on hard rock/soil sites. In general, the earthquake damage
was less intense in structures located on hard rock/soil sites. The distribution of
soil type is rather spotty in the Jabalpur area and for a few locations the soil type
is shown in Table 1-3 (TCPO 1991).

TABLE 1-2. Distribution of top soil in the Jabalpur area (TCPO 1991)

Location Soil Type
Lamenta ghat, Madan Mahal Sandy course
Near Pariyat river, Between Katni Rd. and Sandy silt, Silty clay, Silt, Sandy
Patan Rd. clay
Kanchghar, Poli patthar Sandy caly, Fine clay
Kundam Rd. near Gun Carriage Factory Sandy clay with variations

Near Jabalpur Tank Gravely sandy clay

APPROX. ESTIMATES OF PEAK ACCELERATIONSs
No strong motions were recorded in the most affected areas, therefore, accurate
information about the peak ground accelerations associated with this earthquake
in the epicentral region could not be obtained. The nearest Indian Meteriological
Department (IMD) observatory was about 200 km away from the Jabalpur. A few
estimates of peak accelerations were made at different locations based on over-
turning of small objects, and swaying of fixtures attached to ceilings of buildings
and are summarized in Appendix. Peak accelerations to which these objects may
have been subjected lies in the range of 0.3 to 1.. The corresponding peak
ground acceleration would be much less as structures and objects typically expe

Jabalpur Earthquake of May 22, 1997 5