How to calculate the volume of bathymetry

Hi,

I have just plotted a bathymetry using my xyz data. Now, I need to find the volume of the bathymetry plotted. Anyone has any ideas how can I do that?

Thanks,

Eve

Answer 1

[Chad Greene]

Is your x,y,z data set gridded? If not, grid it, perhaps with gridfit. With your gridded data set (I'll distinguish with capital letters), you'll have some regular grid of Z values corresponding to X and Y values. If X and Y are at, say 100 meter spacing, the area of each grid box is 100x100 meters = 10,000 square meters. A matrix of volume of water in each grid box is then given by

VolumeMap = (SurfaceElevation - Z)*(100*100).

And total volume of water in cubic meters is given by

sum(VolumeMap(:))

[eevee]

Hi Chad,

Thanks. Yes, my xyz has been gridded. But I have included my land data in the volume calculation and now my lecturer gave me the xyz files of the land data. I was asked to use the land data in my matlab script to tell matlab not to included the land data into the calculation. So, now I do not know how to tell matlab about that. Any ideas?

Thanks,

Eve