Thursday, August 7, 2014

[Old fashioned] surveying using an electronic total station: a ~20 year old paper reminds me of the power of detailed 3D mapping

I recall as a graduate student how revolutionary the electronic total station was. I became completely obsessed, and wrote a user manual (after some spectacular failures in the field with my advisor who I think was ready to send me home...). While the original version was written in 1993, I did not put it online until 1999 or so: Total station manual. Koji Okumura also put together a nice guide about the same time: Koji's Digital Mapping Homepage.

I was really interested in both the technical aspects of the measurements, but also the power that they provided in mapping topography and structures for example. I recently reread this nice paper from others who shared my enthusiasm at about the same time: Philpotts, et al., The electronic total station--a versatile, revolutionary new geological mapping tool, Journal of Geoscience Education, v. 45, p. 38-45, 1997.. I wanted to write a similar paper.... Along with a nice review of the basic operations and applications, this paper has a bit of vector analysis that is handy to remember for the processing of any x y z data. I tackled a bunch of that material, especially applied to faults and stress in the Advanced Structural Geology class (week 13).

Time passed and what would take a day to do with the total station (1000 shots) can be done in far less than a second with LiDAR (see the vast holdings and our educational efforts at OpenTopography or Structure from Motion (see for example these SfM posts) topography, but the principles are similar.

Here are a few old images and projects:

Topographic map from the Kule Sayi area along the Altyn Tagh fault (Washburn, et al., 1999).

Topographic map from the Liwiqiming area along the Altyn Tagh fault (Cowgill, et al., 2000).

Topographic map from the Hog Lake site along the San Jacinto Fault (project lead by Tom Rockwell). This site has a lot of nice maps and photos.

Black Canyon City landslid repeat surveys: site.

3D view from surveys at the Montroig Golf Course along the El Camp Fault in southern Spain (from Field training course in paleoseismology Cambrils, Spain, Februrary 2-11, 2001). This site has a lot of nice maps and photos.

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