Bruce Douglas: Using Analyzing High Resolution Topography with TLS and SfM in G429: Field Geology in the Rocky Mountains at Indiana University

About this Course

This is an upper division summer field camp program for later-stage geoscience majors. Although Indiana University (IU) is a PhD-granting university, students come from many different types of schools around the USA. In a typical summer 30-40 different schools are represented.

students (max 22)

~4 days of intense field time and evenings
spent working on field instrument deployment and data collection; data processing; and analysis of the geological problem that has been the focus for that day.

Summer field camp

Syllabus (Acrobat (PDF) 540kB Nov2 16)

I first integrated TLS into Indiana University field camp in 2010. It was an experiment as we were not aware of any other undergraduate programs, including both instrument courses or summer field courses, teaching TLS at the time. As always with teaching new topics, there were some challenges in figuring out how to best engage the students and keep them actively involved in the field and how to get data and software to individuals' computers. However their overall enthusiasm for the geophysics learning and their clear progress over just a few days – moving from basic survey design to applying it to different geologic research questions – has been truly satisfying. Since then we have gradually expanded the teaching materials to include more geologic applications and have added a computer cluster to our facilities which has addressed the problems of data uploading via a server and software already loaded and available. TLS has become a mainstay elective for students at the field camp – repeated every year since its start.

It can be a challenge to keep a dozen students involved and occupied when there is only one scanner, which only a few students can be operating at a time. These teaching materials fold in many years of experience in making sure that students experience all the different observations and activities needed to really understand how TLS works and the supporting data that needs to be collected. In addition to scanner operation students set up other equipment such as targets and GPS antennae, complete scan parameter worksheets to optimize the scan for the available time and research needs, and make traditional field observations and sketches. Thus TLS scanning becomes a tool that extends how they can observe Earth processes but is clearly still tied to fundamental field skills and math.

The annual student evaluations are uniformly positive with comments about how pleased the students were to have learned about this new and powerful geodetic tool. I have even had a student report back that learning TLS method and applications while at field camp influenced her ultimate path in graduate school.

My Experience Teaching with GETSI Materials

I have used all the units in the module except Unit 4: Change detection. The versions of Units 2 and 3 assignments were somewhat modified to fit the specific problems chosen in a given year and the associated field sites near the Indiana University Geologic Field Station.

Relationship of GETSI Materials to my Course

The summer field program, G429: Field Geology in the Rocky Mountains, is 7.5 weeks long. At the outset students learn fundamental field observation and mapping skills in a more supported environment with more faculty interaction. As the summer goes on students work increasingly independently from instructors and fellow students. Around the fifth week, they have the option to choose from four electives, including geophysics (TLS surveying).

I have always worked with a UNAVCO field engineer for the technical side of running the Riegl scanner and managing the data. UNAVCO has a process for requesting field geodesy education support. One of the particular challenges for using TLS in the intense IU field camp setting is the short turn around time between data collection (daytime) and analysis (evening). Students write up all their work individually even though they work in teams for data collection.


Unit 5 is the summative assessment for the module. On the fourth day of TLS surveying, students are introduced to a new field site with a geologic research question and asked to work in their teams to design an appropriate survey. Each team then makes a presentation presenting their primary scientific objective/s, their plan, and their rationale for what they are proposing. As there is only one scanner, the different teams then need to negotiate between themselves the best elements of the different suggestions to reach a final plan. With very little instructor support, the students divide up the survey tasks and execute the survey. The groups are expected to be able to run all aspects of the surveys completely independently. The sites used for the summative assessment have varied over the years ranging from portions of the IU Field Station to other sites with the potential for several problems to be identified. Students turn in the write-ups individually, which are due later that evening. This includes the scanning procedure documentation and equipment check list.


My original goal for introducing TLS was for students to learn a valuable field method for obtaining high-resolution topographic data. As time has gone on, I have increased the emphasis on the geologic research questions that can be addressed with the data. I have found that the majority of students accomplish the learning goals and gain significant confidence on using a method that initially appears daunting and complicated.