GIS Tools For Digital Field Geology: from paper to PDA

Dr. Ben Crosby, ISU, Department of Geosciences

Traditional Geologic Mapping

Traditional Analog Tools Are:

•Durable•Light weight•Easy and fast to learn/teach•No batteries (easier field logistics)•Inexpensive (to obtain or replace)

Digital Geologic Mapping: given the benefits of traditional methods, why go

digital?

•Increasing demand for space exploration tools (read: funding)

•Technology is ready to be applied, active development

•Visualization of multiple layers of data in the field = better mapping:

•Multi-band satellite imagery•High resolution aerial photos•Climate or vegetation data•Geophysical data

•Gravity or magnetometer•Seismic data

•Previous geologic maps

•Demand from employers/industry

Digital Geologic Mapping: given the benefits of traditional methods, why go

digital?

•Integrate data in single source (sensors) (photos, laser rangefinder, chemical) •Rapid transition from data collection to map production (past hurdle) (no data entry or digitizing)

•Accurate location using GPS

•Real-time visualization of collected data

Idaho State University!Bowling Green State University University of California at BerkeleyMassachusetts Institute of TechnologyTexas A&MArizona State UniversityUniversity of KansasUniversity of Wisconsin, Eau Claireand MANY, MANY others

Who’s on the bandwagon?

Some words of caution:•mixing students with immature/buggy technology detracts from learning geology•equipment is expensive, heavy and easily broken•compared to paper, screens are small and often difficult to read in sunlight•batteries run out, computers crash and data is lost

BUT, there is huge potential for the future (this is the future)

So what’s the potential?

•Full integration of all (modern and traditional) tools for collecting geologic field data•digital compass•digital camera•sensors for chemical composition•distance measurement devices•hardward gets better every month (smaller, lighter, more durable and readable)

•wireless communication with base camp and other geologists(base station and rover concept: observe other maps evolve)

What are the tools available?•Right now, not a lot

•Straight-up ArcPad•Custom scripts running within ArcPad•Custom Scripts running within ArcGIS•Independent software

An Example: Mapsmith (MIT)An ArcPad extension with a suite of editing and text tools that integrate with GPS for the collection of point data.

(Essentially a Digital Field book with some coarse mapping tools)

Digital Field Surveying Tools for Geomorphology

•Wireless GPS Receiver•GIS-Enabled Handheld Computer •Compass-Equipped Laser Rangefinder

= collect and visualize 3D data in real-time!

Ash Deposits

Terrace Gravels

Bedrock

Channel and Valley WidthChannel DepthTerrace Heights, Fill thicknessesSediment Size, Character, LithologyBedrock Orientation, etc…

Yellow dots are stations from laser surveys of channel profiles from 2005.

17 km of the mainstem and ~18 km of tributaries (n = 13)were surveyed in the Waihuka

Yellow dots are stations from laser surveys of channel profiles from 2005.

17 km of the mainstem and ~18 km of tributaries (n = 13)were surveyed in the Waihuka

Perihohonu fan.Perihohonu fan.

-320

-270

-220

-170

-120

-70

-20

0 2000 4000 6000 8000 10000 12000 14000 16000 18000

mainstemT15T16eT16wT17T18T08-09T07T19T06T20T21.5T02T22T25lsT19terT1-fillT1-strathT2-fillT2-strathT3-fillT3-strath

Waihuka Mainstem and Tributaries

Perihohonu fan.

KnickpointAsh DepositsTerrace Gravels

Bedrock

(m)

(m)

Everyone else is doing it, so why can’t we?

There are a number of shortfalls/difficulties/technical reasons why

What resources are there?http://geopad.org/ http://serc.carleton.edu/research_education/geopad/index.html

McGuire et al., 2005