!copyright (C) 2001  MSC-RPN COMM  %%%RPNPHY%%%
*     DZMIN is the minimum thickness (in metres) between
*     2 adjacent layers. NKSURF is the index of the lowest
*     level seen by the sedimentation (the layers below it
*     are combined to increase timestep).
*
      integer nksurf
      real dzmin
      common /dzcond/ dzmin, nksurf