  The two dimensional BTW model of SOC, with probabilistically nonuniform
distribution of particles among the nearest neighbouring sites, is studied by
computer simulation. When the value of height variable of a particular site
reaches the critical value (z c = 4), the value of height variable of that site
is reduced by four units by distributing four particles among the four nearest
neighbouring sites. In this paper, it is considered that, two particles are
distributed equally among the two nearest neighbouring sites along X-axis.
However, the distribution of other two particles along Y- axis, is
probabilistically nonuniform. The variation of spatial average of the height
variable with time is studied. In the SOC state, the distribution of avalanche
sizes and durations is obtained. The total number of topplings occured during
the stipulated time of evolution is also calculated.
