How to generate a contour plot from a set of lines of a 3d plot?

I want to display the plot shown below with a contour plot. I understand that to do this I need to have a 3d surface. How can I create the surface these lines form? I basically need to join the lines with a 3d surface and then plot its contour. The command used for the 3d plot is:

    plot3(x1,y1,z1,x2,y2,z2,x3,y3,z3,x4,y4,z4,x5,y5,z5,x6,y6,z6,x7,y7,z7,x8,y8,z8,x9,y9,z9,x10,y10,z10);

where x1,y1,z1,...,x10,y10,z10 are vectors with discrete data.