﻿T2S 
  OLDHAM: 
  GREAT 
  EARTHQUAKE 
  OF 
  1897. 
  

  

  It 
  is 
  to 
  be 
  noticed 
  that 
  most 
  of 
  these 
  earthquakes 
  were 
  feeble 
  

   ones, 
  which 
  were 
  not 
  felt 
  over 
  any 
  large 
  area, 
  and 
  were 
  for 
  the 
  most 
  

   part 
  local. 
  We 
  have 
  consequently 
  an 
  area 
  covering 
  the 
  part 
  of 
  the 
  

   alluvial 
  valley 
  of 
  Assam 
  on 
  either 
  side 
  of 
  the 
  91st 
  meridian, 
  where 
  the 
  

   conditions 
  were 
  very 
  similar 
  to 
  those 
  of 
  the 
  central 
  area 
  in 
  the 
  hills 
  ; 
  

   that 
  is, 
  it 
  was 
  an 
  area 
  where 
  small 
  shocks 
  w 
  r 
  ere 
  frequent 
  and 
  much 
  

   more 
  numerous 
  than 
  in 
  the 
  country 
  outside. 
  

  

  If 
  we 
  turn 
  to 
  the 
  south 
  of 
  the 
  hills 
  we 
  find 
  a 
  great 
  contrast. 
  Not 
  

   only 
  are 
  the 
  reported 
  shocks 
  much 
  fewer, 
  the 
  combined 
  records 
  of 
  

   Sylhet 
  and 
  Sonamganj 
  giving 
  only 
  20 
  shocks 
  from 
  1st 
  to 
  15th 
  

   August, 
  but 
  there 
  is 
  no 
  indication 
  of 
  their 
  being 
  markedly 
  more 
  

   numerous 
  at 
  one 
  place 
  than 
  another 
  in 
  an 
  east 
  or 
  westerly 
  

   direction. 
  

  

  To 
  the 
  west 
  of 
  the 
  Garo 
  Hills 
  earthquakes 
  are 
  also 
  relatively 
  

   numerous 
  and, 
  what 
  is 
  more 
  important, 
  there 
  is 
  a 
  strip 
  of 
  country 
  run- 
  

   ning 
  out 
  into 
  Bengal 
  where 
  the 
  conditions 
  are 
  very 
  like 
  those 
  of 
  the 
  

   central 
  tract. 
  This 
  is 
  well 
  shown 
  by 
  the 
  records 
  from 
  Rangpur, 
  which 
  

   appears 
  to 
  have 
  felt 
  quite 
  a 
  number 
  of 
  small 
  shocks 
  that 
  were 
  

   not 
  recorded 
  at 
  the 
  neighbouring 
  stations, 
  from 
  which 
  regular 
  returns 
  

   were 
  being 
  received. 
  

  

  An 
  examination 
  of 
  the 
  area 
  over 
  which 
  many 
  of 
  the 
  larger 
  shocks 
  

   were 
  felt, 
  shows 
  that 
  in 
  most 
  cases 
  the 
  shocks 
  that 
  were 
  felt 
  over 
  

   the 
  Assam 
  Valley 
  and 
  north-eastern 
  Bengal 
  did 
  not 
  penetrate 
  

   into 
  Sylhet 
  and 
  Cachar 
  or 
  were 
  only 
  slightly 
  felt 
  at 
  places 
  close 
  

   to 
  their 
  northern 
  boundary. 
  

  

  Taking 
  these 
  facts 
  into 
  consideration 
  we 
  see 
  that 
  the 
  centres 
  of 
  

   the 
  aftershocks, 
  in 
  the 
  period 
  shortly 
  following 
  the 
  main 
  shock, 
  were 
  

   not 
  symmetrically 
  situated 
  with 
  reference 
  to 
  the 
  axis 
  of 
  the 
  range 
  

   separating 
  the 
  Brahmaputra 
  and 
  Barak 
  Valleys, 
  but 
  that 
  they 
  lay 
  for 
  

   the 
  most 
  part 
  towards 
  the 
  northern 
  edge 
  of 
  these 
  hills 
  or 
  under 
  the 
  

   alluvium 
  to 
  the 
  north 
  over 
  an 
  area 
  which 
  extends 
  northwards 
  along 
  

   and 
  near 
  the 
  91st 
  meridian 
  of 
  East 
  Longitude. 
  

  

  ( 
  128 
  > 
  ' 
  

  

  

  