The people, science and technology behind discovery

Mobile GIS

Lighter mobile devices that can run GIS are improving the integration of field and office-based software

By Virginia Heffernan

There are reasons why field geologists have been slow to embrace digital mapping techniques. Laptops are heavy to carry on long traverses and vulnerable to the elements and dying batteries. Smaller devises are often not powerful enough to run sophisticated GIS software. And in most cases, geologists require a hard copy version of the field map regardless of whether they digitize their findings or not.

Yet the lure of being able to store thousands of field measurements and overlay several images on a small PC is convincing many to go digital. Suppliers are responding by introducing lighter mobile devices, designing smartphone applications that can run GIS, and improving the integration of field and office-based software.

“We believe the explorationist of tomorrow will have access to anything from his corporate archive at his vocal command, anywhere, anytime,” says Geoff Wade, ESRI’s team lead for the natural resource industries. “Something with the versatility of the Star Trek Tricorder would seem about right.”

But we are not there yet. The main complaint about the current tools available for digital fieldwork is that memory is often sacrificed at the alter of  greater mobility. To address this problem, geologists are devising a range of data collection techniques that will suit their individual needs and budgets until something better and/or more affordable comes along.

Oregon-based geological consultant Carrie Beveridge, for instance, uses a handheld Trimble GPS unit with sub-meter accuracy that is connected via Bluetooth to a field computer that is powerful enough to run ESRI’s ArcGIS.

“My experience with loading RAM intensive imagery, such as aerial photos, onto a handheld GPS is that the GPS operating system struggled to refresh and would occasionally crash,” she says.

At the Geological Survey of Queensland in Australia, geologists carry full-sized tablet PCs running Windows XP despite their bulk and weight because they  “make it possible to take the office into the field” and the more screen real estate the better,  says Mal Jones, a senior geologist at the survey. 

The survey uses ArcPAD to enter data in the field. For one major project, Jones added a Bluetooth GPS velcro-mounted on the car dashboard to provide cordless linkage to the tablet.  The team logged over 5,500 locations and travelled over 35,000 km and each time they returned to the office, their data was instantly compatible with the office environment.

A similar method devised by researchers at James Madison and Old Dominion Universities in Virginia uses either a Trimble GeoXM pocket PC or xPlore Technologies’ ruggedized tablet PC pre-loaded with bit-mapped scans of topographic maps and aerial photos. The geoscientists reproject the images within ArcGIS, then download them to ArcPAD along with shapefiles that incorporate lithology, orientation measurements and other outcrop data recorded on location. 

While in the field, they use ArcPAD to draw lithologic unit polygons and linear features such as faults and contacts. Back at the office, they upload the data and field interpretations to ArcGIS. When the final map is ready, the ArcGIS shapefiles are exported to KML files for use in Google Earth or other virtual globes.

“We still record data in a field book as a back up because battery power or GPS signals can be lost prematurely,” say Steven Whitmeyer, Jerry Nicoletti and Declan De Paor, co-authors of The Digital Revolution in Digital Mapping published in the April/May edition of GSA Today. The authors concede that the redundancy of plotting a hard copy version may make some geologists question the logic of going digital at all, but insist the extra effort is worth it.

For MapInfo Professional users such as Caroline Hilton, managing director of UK-based Pelican GeoGraphics Ltd, there is Discover Mobile, a GPS-enabled handheld that can be used for field data capture, sample logging, mapping and navigation.

“It is set up to talk directly to a GPS and to enter structural as well as observational data, so is very geologically-friendly,” says Hilton.  “We have a number of clients using this in the field.”

Meanwhile, ESRI is completing the first iteration of their next-generation mobile platform called ArcGIS Mobile. The new application integrates with ArcGIS Server to provide central management and deployment of mobile GIS data, maps, tasks, and projects and can be configured and customized to fit field project workflows.

In addition, a new SDK from ESRI allows iPhone users to embed ArcGIS maps and tasks into their iPhone applications. The API is designed to display maps, execute sophisticated geoprocessing tasks, and record locations.

 “We are confident that once we release the iPhone API there will be a cadre of entrepreneurial developers building mining specific functionality to assist with things like working remotely for an extended amount of time, a strike-slip app and interface capability for geological symbology, etc.,” says Wade “I don't believe the iPhone or iPad will replace the ruggedized laptop or versatile integrated GPS device—I have one of those too—but I'll use one in the field during the day, and the other will never leave my side.”

Regardless of the tools, the ability to assemble draft versions of maps that can be continually evaluated and changed in the field is the main advantage of digital fieldwork, say Whitmeyer, Nicoletti and De Paor. And since all professional geology maps are now created using computer-based graphics programs, geologists can simplify and streamline the process by using compatible hardware and software right from the field collection stage through to final map preparation.

“What I find most remarkable is the workflow convenience of larger memory, a bigger screen size, ruggedized nature and, perhaps most useful, the bewildering connectivity to GPS, 3G telecom networks, wireless—you name it,” concurs Wade.