The following nested loops run correctly if I compile with the OpenMP directives disabled and run sequential. However if I enable OpenMP I get invalid results running either single or multi-threaded. All the arrays are dimensioned the same and the j,i loops run the full range of their dimensions.

```
!$OMP PARALLEL PRIVATE(j,i,duxdx,duzdz,duxdz,duzdx,dtx,dtz) &
!$OMP shared(a1,a2,a3,a4,a5)
!$OMP do
do j=-ntaper+1,mx+ntaper
do i=ntaper_z0,mz+ntaper
duxdx = a1*(sxx(i,j+1)- sxx(i,j))+ &
& a2*(sxx(i,j+2)-sxx(i,j-1))+ &
& a3*(sxx(i,j+3)-sxx(i,j-2))+ &
& a4*(sxx(i,j+4)-sxx(i,j-3))+ &
& a5*(sxx(i,j+5)-sxx(i,j-4))
duxdz = a1*(sxz(i+1,j)-sxz(i,j)) + &
& a2*(sxz(i+2,j)-sxz(i-1,j))+ &
& a3*(sxz(i+3,j)-sxz(i-2,j))+ &
& a4*(sxz(i+4,j)-sxz(i-3,j))+ &
& a5*(sxz(i+5,j)-sxz(i-4,j))
duzdz = a1*(szz(i,j)- szz(i-1,j))+ &
& a2*(szz(i+1,j)-szz(i-2,j))+ &
& a3*(szz(i+2,j)-szz(i-3,j))+ &
& a4*(szz(i+3,j)-szz(i-4,j))+ &
& a5*(szz(i+4,j)-szz(i-5,j))
duzdx = a1*(sxz(i,j) - sxz(i,j-1))+ &
& a2*(sxz(i,j+1)-sxz(i,j-2))+ &
& a3*(sxz(i,j+2)-sxz(i,j-3))+ &
& a4*(sxz(i,j+3)-sxz(i,j-4))+ &
& a5*(sxz(i,j+4)-sxz(i,j-5))
ux(i,j)=ux(i,j)+ (dtx*duxdx + dtz*duxdz) * rho(i,j)
uz(i,j) = uz(i,j)+(dtx*duzdx + dtz*duzdz) * rho(i,j)
end do
end do
!$OMP end do
!$OMP END PARALLEL
```

This is the first time I have tried to run OpenMP in Fortran 90. Usually my code is in Fortran 77.

Do you have any suggestions?