I'm trying to figure out how to calculate area under a transect line.  We have these cross-sections of the Delaware River derived from bathymetric surveys.  We are trying to figure out how to calculate the AREA beneath each line.  I had tried the 3D Analyst tools calculating the volume under a manually-created surface, but that did not give us the results we were looking for.  I have tried searching the Help pages and online forums, but no one seems to have a similar issue.  It seems like it should be a relatively simple solution, but we just aren't seeing it.  I am wondering if anyone can point me in the right direction as far as what tools are available to run this particular calculation.

Thank you, and apologies for multiple postings.

Phil Pierdomenico