C NORTON    SOURCE    CHAT      05/01/13    02:00:55     5004           
       SUBROUTINE NORTON(SIGEFF,EPSH,DT,CA,CN,CM,DEPSC)                         
      IMPLICIT INTEGER(I-N)
       IMPLICIT REAL *8 (A-H,O-Z)                                               
       T1  =CA*SIGEFF**CN
       DRT = ABS ( 1.D0 - CM)
       IF( DRT.LT.1.D-4) THEN
         DEPSC= ABS(T1)
       ELSE                                                       
        TIME=(EPSH/T1)**(1.0D0/CM)                                               
        IF(TIME.LT.DT) TIME = ABS(DT)
        IF( TIME.GT.1.D30) TIME = 1.D30                                           
        DEPSC= T1*CM*TIME**(CM-1.0D0)  
       ENDIF                                          
       RETURN                                                                   
       END