We issued a complete kit to each student about a month before leaving for summer field, explaining the basic concept and going over some of the setup in a one-hour meeting. This was then followed by a half-day field excursion to give the students the opportunity to create a simplified geologic map (we chose to keep this an ungraded exercise). One of the first exercises we did was to go to a large, dipping bedding plane, have each person in the class take a strike-and-dip of bedding using their Brunton compasses (which I recorded in my field notebook), and then had each person in the class take the same measurement using their iPad (again I recorded). This was a good confidence boosting exercise for both the instructor and class, as a shotgun-blast of compass-collected data (attributed to student measuring error not the compass directly) shrunk to a +/- 2 degree iPad-collected data cluster.

We reissued the iPad kits to the students about 1.5 weeks into the Summer Field course, after they completed a large traditional mapping project (Eastern California's classic Poleta Folds). The focus of this project was mapping the bedrock geology in a structural and stratigraphically challenging setting with very well-exposed outcrop. The first digital exercise assigned to the students was a 0.5 mi x 1.5 mi region immediately south of the area they had just mapped.

The students had a half day to interpret the geology remotely from the field classroom (drawing faults, folds and unit contacts from aerial and lidar imagery), one full day in the field to map as much as they could, and then an evening to refine their map before submission. By having their first digital project in a geological environment they were well acquainted with (climate, terrain, geology), the students could focus on learning to use the iPads effectively. This was a unique and effective exercise in several ways: (1) the students learned they could efficiently map the geology of an area remotely from high quality imagery if they were equipped with local experience and background knowledge of what they could expect to find, (2) the students were exposed to the real world scenario of not having as much time on a project as you would ideally like, and (3) the students could form a more direct comparison of the advantages and disadvantages of traditional field mapping methods compared to current digital mapping methods since they were mapping a new region but with familiar stratigraphy and structures (they found that they could take more measurements and cover more ground in less time, but found screen glare and glitches to be new challenges).

Although three or more field days could have easily been spent mapping this region, both I and the students were impressed with what they were able to map in 1.5 days. Student feedback suggested this project served as an effective bridge into the digital field mapping world.

• A 2-day project focusing on mapping metamorphic rocks and their relationships to a pluton in an alpine setting (Crooked Creek, White Mountains, CA)

• A 1-day project focusing on mapping glacial geomorphic features of multiple ages (Convict Lake, Long Valley, CA).

• A 2-day project focusing on mapping multiply-deformed metamorphic roof pendant rocks and their relationships to intrusive rocks in a forested setting (Gull Lake, Eastern Sierras, CA).

• A 2-day project focusing on mapping volcanic lithofacies, vent locations, and former lake shores on an emergent subaqueous-subaerial Surtseyan volcanic edifice (Black Point, Mono Lake, CA).

• A 1-day project focusing on analyzing rock slope stability of blasted roadcuts along a gated access road (Owens River Gorge, CA). The iPads were used to efficiently take structural measurements but not really for mapping.

For simplicity we had the Summer Field students make all their finishing touches within FieldMove (or Google Earth if they preferred), then export their project as a KMZ, which was shared to a Google Drive folder by the deadline. I then created a folder in Google Earth on my PC, which allowed me to easily order the student projects from best to worst. By layering several at a time it was very easy to check for cheating.

If you wanted to take the projects further (e.g. have more time available in a classroom setting) you could have the students examine their field data in Move and use it to create balanced cross sections, or take their data to ArcGIS or Adobe Illustrator to do a final "published map style" draft.

This digital field mapping system is well suited for teaching students to map in a quadrangle-style where groups of 2-3 students map a rectangular region which abuts regions other students in the course must map. To do this you can pre-load the different "quadrangle" boundaries onto a basemap or have the students draw it on later. At the end of the project the students must submit a final detailed map of their sub-region, and a smaller scale map where they aggregate the entire class' tiled data (made available in a shared Google Drive folder) into a "seamless" (and inevitably simplified) map covering the entire student mapped area. This will teach them about how many professional geologic maps are made, how different geologists place different emphasis on the features they see and map, the challenges in compiling maps from different sources, and how large-scale field mapping is often simplified for clarity on small-scale final maps.

A variation on this exercise would be to give students a geologic map with a region extracted as a basemap, and task the students to map the extracted region in the same style of the existing geologic map. Be sure it is not a map they could easily find though!

The tablets enable collection of structural data at considerably greater efficiency and accuracy than students are capable of with a Brunton compass. This allows them to accumulate a vast dataset in a very short time in the field and then pool their data back in the classroom (strike-and-dips, fault kinematic data, paleocurrent data, etc). Ideally in the future the AirDrop functionality would allow direct import into different devices' FieldMove program.

In contrast to paper maps which must always have a fixed scale, the ability to instantly pinch your way between any scales (say 1:500 and 1:24,000) on a digital map means that you can readily teach students about the importance of scale in digital mapping. If you select a field area that has patchy outcrop overall but some very revealing mappable outcrops, you can emphasize the importance of mapping these outcrops in detail to better understand and map the less exposed regional geology. This works well in structural scenarios where small features mimic large (e.g. parasitic folds to a regional fold, secondary faults to a larger fault). The students had to learn this technique to some extent in our Black Point exercise where relationships between volcanic lithofacies were exposed in a few key cliff sections.

The field mapping exercise could be taken further (and expanded in duration) by teaching students how to use UAV (a.k.a. drone) photographs and structure from motion (SfM) photogrammetry techniques to create their own basemaps (high-resolution orthophotographs, hillshades, and contours). The exact details are beyond the scope of this website but essentially this would require (1) one (or more) field sessions to collect the photos and GPS control points, (2) a lab session to process the data in SfM/GIS programs (e.g., AgiSoft PhotoScan, ArcGIS) and export products to the iPads, (3) one (or more) field sessions mapping on the basemaps in FieldMove, and (4) potentially another lab session (or several) to export and manipulate the data. This is a workflow likely to become much more prevalent in industry and research due to the relatively low cost and ease of use. This concept was demonstrated successfully over a two-day field trip in my Fall 2016 graduate-level Modern Field and Visualization Techniques course (to the delightfully unvegetated and wonderfully exposed Rainbow Basin in the Mojave Desert). Exporting orthomosaics as MBTiles in PhotoScan (with or without contours) can easily be uploaded to the GeoPads in the field to allow students to map on it immediately. If you are really organized, willing to submit to the positional accuracy of the UAV's GPS (~3-4 m), and bring a laptop in the field for processing, it is possible to be able to go through this whole workflow with the students in less than an hour! The resolution of the data was considerably better than the ~5 pts/m2 point density in the 2007 EarthScope airborne lidar data collected for the same area. This greatly impressed the students!