MOVING DIGITAL TERRAIN ANALYSIS TO THE FIELD: NATIVE APPS ON SMART PHONES AND TABLETS

The confluence of increasing technological capabilities and higher resolution digital data means that both scientists and hobbyists can perform sophisticated terrain analysis operations in the field on industry standard hardware. Choices for the architecture include: (1) running entirely within a web browser; (2) using web services to access data, and perform computations, and then manipulating them on a program on the local device; (3) running on a Windows tablet using the normal desktop software; and (4) storing data locally and processing it on a native program on the local device. Because the first two options require an internet connection, they could be prohibitively expensive or completely unavailable for many field locations. A Windows tablet, like the Microsoft Surface Pro 3, in many ways duplicates and could replace a laptop computer, but has two limitations: no GPS built in, and size significantly bigger than a tablet like the Nexus 7. Android tablets, and cell phones which can run the same software, easily fit the user’s hand or the pockets of a field vest. They have sufficiently data storage to download imagery, digital elevation models, lidar data, and vector overlays, and while processing is slower than on desktop or laptop systems, tablet performance is rapidly improving and a user in the field has limited alternatives. With development tools like Embarcadero’s Delphi, the same code can run on 4 operating systems: Windows and Mac desktops, and iOS and Android handhelds. The closed ecosystem of iOS handhelds complicates software development and deployment, but the cost of an Android tablet makes it affordable as a field tool. The base code for the MICRODEM freeware program now runs on all 4 systems, and the user interface is being adapted. We will demonstrate basic 2D and 3D map displays, computation of geomorphometric parameters, and applications particularly suited for field use such as projecting a plane’s outcrop pattern from a measured dip and strike. Doing terrain analysis in the field allows testing hypotheses and verifying relationships immediately, and can make field mapping more productive. Prototypes like Google Glass or Occulus Rift might find practical applications in the future, but with the right software current handheld devices can greatly improve the efficiency of field geologists.