OF-99-386: Present and Future Issues of a Mapping Program

Digital Mapping Techniques '99 -- Workshop Proceedings
U.S. Geological Survey Open-File Report 99-386

Present and Future Issues of a Mapping Program

By Frank Ganley

Alaska Division of Geological and Geophysical Surveys
794 University Avenue, Suite 200
Fairbanks, Alaska 99709
Telephone: (907) 451-5005
Fax: (907) 451-5050
e-mail: frank@dnr.state.ak.us

INTRODUCTION

At the 1998 Digital Mapping Techniques Workshop, Gail Davidson of the Division of Geologicaland Geophysical Surveys presented some of the experiences and problems that the Survey has encountered during the development of a digital mapping database (Davidson, 1998). The result of this presentation was a flood of good advice from the workshop participants. Since the '98 workshop we have been putting some of those ideas to work.

WHERE WE HAVE BEEN

One suggestion offered, during the workshop last year, was the incorporation of ArcView into our mapping program. Participants from other surveys pointed out the ease of on-screen-digitizing with this software. This was seen as an attractive tool to get project and field geologists more involved in entering and processing their data. The ease with which existing data sets could be viewed and analyzed also was also seen as a useful addition to our system.

Since last year we have added ArcView to our Unix system and several of our staff now have it installed on their PC's. The result of this seems to be increased interest in data entry and manipulation by formerly "non-GIS" people. The ease with which the existing data sets can be accessed and combined offers exciting possibilities. In the past, combining old geology and new, geophysics and geochemistry, or remotely sensed data and geophysics, was something that only the "computer guys" could do on the Unix workstation. Now, the possibility exists for any geologist to manipulate the data themselves on their own PCs. Many informational maps for reports, and topographic bases for mapping purposes have been produced. ArcView will be in the field, on laptop computers, during at least one project in the 1999 field season. It is our hope that this new excitement over GIS will get our people to look at their data not only as map-specific information, but also as data that can be used in the future for analytical purposes.

While this new found enthusiasm for GIS is encouraging because of the increased efficiency in production that it can bring, it also carries with it a new set of concerns. Although ArcView is fairly user friendly and the basics can be learned very quickly, proficiency takes some time. Part of being proficient in any GIS system is an awareness of the structure of the database and how the data being generated fits into that structure. Some control has to be maintained over the way existing data is handled and where new data is stored and maintained. For instance, ensuring that data sets that are sitting on someone's PC eventually make it into the agency's server will take both discipline and training. This is not an insurmountable problem, however it is an issue that has to be addressed. Along with the overall organization of the database is the concern over the differences in formats between Arc/Info coverages and ArcView shapefiles. It isn't clear to us yet whether the difference in formats will limit what we produce in ArcView. Our existing data is in Arc/Info coverage format. Although ArcView shapefiles can be converted into coverages, it doesn't seem to be an entirely straightforward process. Can we produce polygon shapefiles and convert them to coverages without losing accuracy? Can we take coverages and convert them to shapefiles for editing purposes and convert them back to coverages all the while maintaining the integrity of the data? Before we start generating large shapefiles for use with existing data, we need answers to these kinds of questions.

Another way that we have gotten geologists in closer contact with their data is by upgrading our plotter technology. Until about 18 months ago all of our plotting was done on a Versatec plotter. This plotter was available only through the Unix system and as a result plotting jobs had to be performed by a select few people. We are in the process of phasing out the Versatec. We presently are using two HP 2500's in addition to the Versatec and by July 1 will be using the HPs exclusively. These two plotters are available through all of the PCs. Geologists are now able to plot their own test plots, informational maps, and posters directly from their desks. Because they no longer need to go through someone that knows the Sun system, it has encouraged more experimentation with data than we had seen before.

WHERE WE ARE GOING (WE THINK!)

The hot topics of conversation in the GIS/Geology world of late seem to be interactive maps and 3-D mapping. We are currently looking into putting three-dimensional views of some of the Aleutian volcanoes on the Alaska Volcano Observatory web page (http://www.avo.alaska.edu/). We have also had some discussion of 3-D geologic mapping as a part of our future plans. It is difficult to try to envision exactly what these new technologies will mean to our business but one thing is certain. The trend is away from the traditional two-dimensional paper map product in favor of data packaged in digital format. Whether this means digital data on compact disks, maps served over the Web, or a combination of these and other, yet to be conceived, delivery systems, remains to be seen.

The question now is - what's the next step? We've made some headway in the past year. We are confident that many of the questions asked in this paper will be dealt with in the near future. Many of the goals we set and discussed after the workshop last year are still valid and some are becoming a reality, but what is next? What should we realistically look at as the next level in building our database and mapping program? We face some very real limitations in the future due to an oil-price driven state budget crisis. It is more important than it has been in over a decade that we are as efficient as possible and that we make that efficiency apparent to the people that we serve. The dilemma becomes how to do this and still keep abreast of the advances in technology.

REFERENCES

Davidson, Gail, 1998, Can We Get There From Here? Experiences of the Alaska Division of Geological and Geophysical Surveys, in D.R. Soller, ed., Digital Mapping Techniques '98 - Workshop Proceedings: U.S. Geological Survey Open-File Report 98-487, p. 13-14 https://pubs.usgs.gov/openfile/of98-487/davidson.html.