The video below shows a work process example of the Import Boring Logs command, how to read and interpret Site Investigation Reports and create a Boring Logs File that can be used with the RPS Import Boring Logs command.
It reviews a few issues that you may want to consider when it comes to interpreting strata
- Whether to use Elevation or Depth Models for the strata surfaces
- Limiting the Original Ground to just the area of the Site Investigation (or at least not much larger than the area covered by boring logs
- How to group and select the critical material layers in the strata and to determine whether or not they are important for your calculations
Hope the video helps - I revised the model to add a Site Boundary to restrict the OG and the related strata after the video was recorded - this limits the extents of the strata and removes the ambiguity outside of the site limits.
If you are looking for tips and guidance on whether to use Elevation or Depth models for the strata - you have to look at the strata materials. Sand, Gravel, Clays, Cobbles etc. are typically laid down by water or glacial action (Rivers, Lakes, Oceans) and will typically be laid down on the existing surface in layers. However any irregularities in the existing surface will typically get filled with sediment pockets etc. so when you create surfaces for these materials they are more likely to follow the existing ground, the depth from the ground will vary by the depth of materials in the boring logs, but between boring logs they will more likely follow the terrain rather than be determined by the elevations of the strata in the boring logs.
Igneous and Metamorphic rocks are created by intrusion or by heat and pressure modified strata so they tend to be more determined by Elevation because they do not follow the terrain (except for lava flows / mud flows, pyroclastic fall outs that do get laid down on the terrain in somewhat parallel layers (Depth Based again).
In this example the strata layers while somewhat stratified based on the naming provided, most can be considered alluvial or glacial materials (Clays, Sands, Gravels with or without cobbles) and therefore I would pick Depth Method to compute them most likely.
Note also that man made features like roads or buildings etc. that may form the Existing terrain model do not represent the ground in those areas that would have existed when the geology was created - it can help your model if you remove those features from the Existing Ground Surface for the purposes of computing your strata surfaces, and then add them back for the purposes of Volume Calculations - note that doing this may mean that you have strata layers above original ground so you typically have some editing to do to make it all work - if there are few or no man made features in the OG then of course there is no need to do this. Be aware of the affects of Man Made Features on Geology surfaces - they are not ideal but in the grand scheme of things may not influence the strata cut quantities that much (and they are a best guess based on limited boring log data anyhow).