Blank faces in surface plot

Hi,

I have non-uniformly spaced data and am using meshgrid, griddata & surf to obtain a surface plot. Since my data has discontinuities, I would like to have the plot show an empty face corresponding to those coordinates. Is there a way to do that? My current code is as below:

 xlin = linspace(min(x),max(x),300);
 ylin = linspace(min(y),max(y),150);
 [X,Y] = meshgrid(xlin,ylin);
 Z = griddata(x,y,z,X,Y,'cubic');
 figure;
 surf(X,Y,Z);

Discontinuities in my function values (z) are represented by NaN. For eg. at x = 1650, y = 150, z is set as NaN to represent a discontinuity.

Thanks!