Adjust LiDAR to ground control points question

WetlandGuy

We had lidar flown of a 9,000-acre dry lakebed that is approximately 5-miles long at its longest point and 2.5-miles wide at its widest point. It was discovered that significant ground subsidence occurred after the lidar was flown. Subsequent ground truthing RTK surveys show anywhere from 6-inches to two-feet of subsidence. The lake has now been re-filled, with no way to drain it, making resurveying it very difficult and expensive. 

 

If we could obtain a “grid” of ground truthing points across the lake, would Globalmapper be able to “fit” our existing lidar surface to the grid of points using the “Lidar QC/Compare/Adjust” function? What would be an appropriate grid size for the software to use ( would 1,000-feet x 1,000-feet be sufficient)? I have V25Pro and noticed that version 26 there are a couple more options (Fixed Z Shift and Best Fit Plane). Any suggestions would be helpful. Thanks.