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Computer-Based Data Acquisition and Visualization Systems in Field Geology

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Computer-Based Data Acquisition and Visualization Systems in Field Geology Computer-based data acquisition and visualization systems in fi eld geology: Results from 12 years of experimentation and future potential Terry L. Pavlis, Richard Langford, Jose Hurtado, and Laura Serpa Department of Geological Sciences, University of Texas at El Paso, El Paso, Texas 79968, USA ABSTRACT attributing is limited to critical information tem (GPS) receivers, digital cameras, recording with all objects carrying a special “note” fi eld compass inclinometers, compass-inclinometer Paper-based geologic mapping is now for input of nonstandard information. We devices that log data and position, and laser archaic, and it is essential that geologists suggest that when fi eld GIS systems become rangefi nders allow us to do things that were transition out of paper-based fi eld work and the norm, fi eld geology should enjoy a revo- impossible only a decade ago. This technology embrace new fi eld geographic information lution both in the attitude of the fi eld geolo- allows new approaches to obtaining, organizing, system (GIS) technology. Based on ~12 yr gist toward his or her data and the ability to and distributing data in all fi eld sciences. This of experience with using handheld comput- address problems using the fi eld information. technology will undoubtedly lead to major new ers and a variety of fi eld GIS software, we However, fi eld geologists will need to adjust advances in fi eld geology, and hopefully revital- have developed a working model for using to the changing technology, and many long- ize this foundation of the geosciences. fi eld GIS systems. Currently this system uses established fi eld paradigms should be reeval- In this paper we explore this issue of changing software products from ESRI (Environmen- uated. One example is the rule that all line- fi eld technology based on 12 yr of experience, tal Systems Research Institute, Inc.) (ArcGIS work on geologic maps needs to be perfected during which we have progressed from using and ArcPad), but the data model could be in the fi eld setting. Our experience suggests computerized fi eld notebooks to using a variety applied to any GIS system. This fi eld data that with modern high-resolution imag- of fi eld GIS systems for research and teaching model is aimed at simultaneously increas- ery (aerial photography and topographic applications. We describe the present state of ing the effi ciency of fi eld work while adding shaded reliefs) and digital elevation models, fi eld mapping technology from our experience, the attributing capability of GIS to develop fi eld work should evolve into an iterative and discuss the advantages and disadvantages fi eld data products that are more data rich process where map linework is roughed out of different approaches and technologies. Key than any paper map could ever achieve. We in the fi eld, refi ned during evening fi eld ses- to this discussion is a philosophical difference emphasize three basic rules in the develop- sions, then potentially revisited if problems in attitudes toward how data are collected and ment of this data structure. (1) A fi eld GIS arise. This procedure is particularly effi - organized. Finally, we provide some thoughts map should emphasize line and point objects, cient when three-dimensional visualization is on how we might proceed in the future. avoiding polygons, objects that can easily be added to the system, a feature that will soon One important lesson we have learned is that constructed outside of the fi eld environment. become the norm rather than the exception. no single system is perfect for all applications, (2) Keep it simple stupid (KISS) is a critical We note that using these systems is particu- and the worst systems are ones that seem logical rule for setting up data structures to avoid larly important for future developments in in the laboratory but are totally impractical in fi eld GIS systems that are less effi cient than metamorphic geology, sedimentary geology, a fi eld situation, or vice versa. We discuss how paper. (3) Data structures need to develop a and astrogeology, but other applications are these technologies can be applied to metamor- compromise between display and data entry, clearly also possible. For geoscience instruc- phic geology as well as economic geology, and with display always trumping data entry tors who teach fi eld geology classes, we note describe how further development of these tech- because geologic insight is the primary goal. that it is critical that these systems be incor- nologies will be crucial to future planetary geol- This paper contains two sample blank data- porated into all geoscience fi eld programs, ogy expeditions. We then consider the similarly bases that illustrate these approaches for two but research is needed on the best teaching revolutionary impact the technology can have applications: (1) generic bedrock geologic approaches in the use of the technology. on teaching fi eld geology. mapping, and (2) metamorphic geology map- ping multiple generations of fabrics. Key fea- INTRODUCTION HISTORY OF THE TECHNOLOGY tures in our approach are to use display as a fi rst-order attribute, sorting point objects Until recently, the tools of the fi eld geologist Until the mid-1990s, computer systems were into four basic types (station, orientation, have seen little change since the nineteenth cen- not practical in the fi eld for any application sample, photo) and lines into the four basic tury: a hammer, a hand lens, and a geologic com- other than simple data logging or for support of contact types (depositional contact, uncon- pass with inclinometer. We have now entered geophysical surveys, the latter typically associ- formity, intrusive contact, fault), plus other a new era in technology where rugged, light- ated with substantial logistical support (Table specialized data layers where needed. Indi- weight fi eld computers, geographic information 1). The problems with early portable computer vidual GIS objects are further attributed, but system (GIS) software, global positioning sys- systems were fourfold. Geosphere; June 2010; v. 6; no. 3; p. 275–294; doi: 10.1130/GES00503.1; 7 fi gures; 2 tables; 2 supplemental fi les. For permission to copy, contact [email protected] 275 © 2010 Geological Society of America Downloaded from http://pubs.geoscienceworld.org/gsa/geosphere/article-pdf/6/3/275/3339183/275.pdf by guest on 02 October 2021 Pavlis et al. 1. Power. The battery life of laptops of the resistant as is common with modern, rugge- With the introduction of the fi rst handheld time was far too short for a full day in the fi eld dized fi eld computers. computers in the early 1990s, many of these without large packs of spare batteries. More- 3. Displays. All of the early liquid crystal dis- issues were overcome with a device of man- over, the lead-acid and nickel-cadmium bat- plays (LCD) became unreadable in bright sunlight. ageable size and heft, a long battery life, and teries in common use at the time were heavy, 4. Processing and communication. Process- a satisfactory (initially monochrome), outdoor- bulky, and slow to recharge. ing power for early portable computers was readable display. That development led many to 2. Portability. Computers were too heavy insuffi cient to run even the modest GIS software consider using these devices by the mid-1990s and bulky to carry the large distances geolo- that was available. In addition, wireless commu- (Table 2). gists travel on foot. Furthermore, the hardware nication and GPS positioning technologies were With the present generation of devices was fragile and not impact, water, and dust not widely available. and software, computerized fi eld mapping is TABLE 1. HISTORY OF DEVELOPMENT OF MODERN FIELD SYSTEMS Year Hardware Software development Experiments by authors* Experiments by others development First reasonably priced GPS Software developers work in GIS used by many for offi ce 1990–1991 GIS and computer graphic None devices become map development available fi elds ESRI introduces Arcview GIS; MapInfo Introduction of fi rst and Intergraph GIS Limited use of GPS GIS becomes widespread 1992 pen computer alternatives; handwriting- handhelds and GIS as mapping tool, but no (GoPoint) recognition software software fi eld usage introduced with pen computers 1993 First PDA (Apple Continued developments No new experiences GIS usage continues Newton) in GIS Geological Survey of Pavlis writes “I have a Early pen-based Canada develops dream” essay on potential Geological Survey of 1994–1995 devices rejected in Fieldlog system; Penmap of technology for fi eld Canada begins fi eld mass market development for pen applications with Fieldlog computers applications Palm Pilot and Windows CE Initial testing of software and Initial experiments by 1996 PDAs introduced; Penmap initial developments hardware several groups Win95 pen tablets available Transfl ective J.D. Walker (UK) and B. Brimhall (UC Berkley) (sunlight) GIS software improves; First fi eld experiments with screens appear; ArcGIS 8 (1999) and begin fi eld experiments handheld devices using 1997–2000 pen computers ArcPad 5 (2000) Fieldlog and Penmap in with Arcview and Penmap, improve; digital introduced; GPS respectively; many groups cameras become incorporated into GIS Alaskan and Death Valley experiment with various affordable for software fi eld work dataloggers (e.g., Palm, routine fi eld work WinCE, Psion) Abandoned AutoCad-based UC Berkeley group ArcPad 6 together with Fieldlog applications in continues development Tablet PC for favor of ArcPad-ArcGIS of Geomapper; UK group Wintel (1992); ArcGIS 9
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