Your data describe an outline in a plane. If you want to see it as a volume, duplicate the x and y values, add an offset to the second z value, and use the surf function or similar functions to visualise it.
Example:
x = [1 2 3 4 4 4 5 6 6 5 5 3 1];
y = [4 6 8 9 9 8 7 6 5 4 5 4 4];
z = ones(size(x));
figure
plot3(x, y, z)
grid on
xlim([0 8])
ylim([2 10])
figure
surf([x; x], [y; y], [z; z+5])
grid on
xlim([0 8])
ylim([2 10])
shading('interp')
I do not have your data, so I created my own.
Experiment to get the result you want.
