Sizing Up the Rocks – GigaPan Imagery in the Geology Classroom

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[This is a guest post by Professor Chuck Bailey of W&M's Geology Department.]

The rocky crust of the Earth provides a tangible puzzle for geologists to solve. I teach a second-level geology course entitled Earth Structure & Dynamics and one goal of the class is to develop students’ skills at reading the rock record. To that end, we go to the field and practice doing geology when we can, but we also have new tools that allow us to examine outcrops from the comfort of the classroom. One of these new tools is GigaPan, a website that hosts user-produced ultra high resolution “gigapixel” panorama images, as well as the software and information you would need to make your own GigaPans.

What Is a GigaPan?

GigaPans are digital panoramas composed of millions to billions (thus the “giga” prefix) of pixels.  To create a GigaPan, a camera on a motorized mount takes overlapping high-resolution pictures while it drives over a pre-defined grid. Individual images are then stitched together to create the GigaPan scene.  Photographers use this technology to capture spectacularly detailed images.

Earth scientists are taking GigaPan panoramas of hand samples, outcrops, and landscapes, and in the process creating new opportunities for students to observe and interpret the earth. In January I took a number of GigaPans during my research trip to Oman with the idea of rolling these panoramas out as practice for my students back in Williamsburg.

Above is one of the GigaPans I created.  To get an idea of the detail and scale of the image, be sure to use the zoom feature and take a look in fullscreen mode (via the button directly below “view all”).

My Experience with GigaPan in the Classroom

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William & Mary geology students savoring their first GigaPan geology experience.

Last Friday I served up a panorama from a road cut along an expressway in northern Oman that exposes tilted Mesozoic strata and asked my Earth Structure & Dynamics students to investigate the outcrop. On their laptops students could zoom in and examine the outcrop in glorious detail. A quick glance at the image is enough to work out that the multicolored strata are moderately inclined, but a closer look reveals that reddish mudstones are overlain by a sequence of interlayered blue-gray carbonates and beige shaley carbonates. There’s also a menagerie of geologic structures, such as folds, conjugate faults, and thrust faults throughout the scene.

Students worked in small groups and annotated a printed image of the outcrop while they zoomed in and out of the digital scene.  In many respects this is similar to what a geologist would do in the field, inspecting the outcrop from a distance to work out the macro-scale geometry and then taking a detailed look at individual layers and geologic structures.

Our first foray with GigaPan imagery was not without a few hiccups. As a member of the GigaPan community I can add ‘snapshots’ to a panorama (check them out in the embedded scene above) and had hoped my students could do the same — crowd sourcing the interesting bits. Yet, they needed to be registered as GigaPan community members to contribute. That said, my students teased out many of the exciting structures visible only by close inspection of the detailed images and we had a rollicking group discussion about the geologic history of this far-away outcrop in the Oman desert.

Some Final Thoughts

This technology seems well suited for other academic endeavors where synoptic to detailed views are needed to properly interpret a scene or space (e.g. a landscape, a historic building, large artwork, etc.). The scalable viewing of a scene works equally well for the macro-scale (such as a cityscape) as the micro-scale (such as a scanning electron microscope image).

Detail of the lower right corner from the GigaPan scene (above) with annotated version of the detailed scene to the left.  Thrust fault (thick red line) cuts through strata, repeating layers a and b. The thrust fault tips out and the layers above the fault (layer c) are deflected, but not faulted.

Detail of the lower right corner from the GigaPan scene (above) with annotated version of the detailed scene to the left. Thrust fault (thick red line) cuts through strata, repeating layers a and b. The thrust fault tips out and the layers above the fault (layer c) are deflected, but not faulted.

I’d like to be able to annotate the imagery using the GigaPan software and have my students try their hand at it as well, but that is not possible using the interface through which the imagery is served up on the GigaPan website. To create the figure above, I exported the high-resolution scene into Adobe Photoshop then cropped out a detailed area and finally annotated the scene in Adobe Illustrator — not very streamlined. Unfortunately, GigaPan is also struggling financially — the company released many staffers recently and the last November the CEO resigned — we shall see what the future holds.

GigaPan imagery won’t replace field experiences for W&M geology students, but the medium has much promise for 1) preparing students to do geologic fieldwork and 2) illustrating the geology of places and scenes not accessible during our semester-long course.