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Jump to UMass Department of Geosciences Home PageABSTRACT Dynamic Digital Map-Springerville Volcanic Field (DDM-SVF) is a stand-alone "presentation manager" program that contains and displays four thematic geologic maps of the Springerville volcanic field, Arizona, on the Macintosh computer. It is essentially a complete "geologic map on disk" (CD-ROM). Because of its digital format, the program contains far more data than even the most complete analog maps. This digital map offers several advantages over hard-copy maps in that it simplifies finding samples (or units), makes information on map features and associated digital photos instantly available, and allows sequential changes in thematic map type. The maps can be printed out in color on desktop printers, or saved as separate files, and all data can be saved from the program to tab-delimited ASCII format, making the data easily accessible and accurately transferable to other workers. Maps of this type offer a venue for producing high quality color maps and associated data quickly and efficiently, and can be distributed electronically (for example by Internet) or on disk (either diskettes or CD-ROMs). (Figure 1 - DDM Overview) (Figure 2 - Detailed Area Map) (Figure 3 - Aerial Photograph) INTRODUCTION Desktop computers today offer a new meduim for presenting geologic maps, brought on by the development of "hypermedia" programming languages (or "environments"). One such program is SuperCard, which has been used to produce DDM-SVF, a prototype geologic map on disk now available on CD-ROM from the Geological Society of America (Condit, 1994). Hypermedia environments provide an efficient way write software to link maps, data or digital photos into an interactive framework providing the geologist immediate access to both the map and its associated information. An example of such a link: a geologist looks at a map on the screen, sees a symbol for a chemical analysis or a map unit and, using a mouse, clicks on the symbol, immediately bringing up a window containing the chemical analysis or unit description. Maps and data can be easily inserted into such a program; an example is SuperMap7/23/92 (Condit and Neutra, 1992), which is included on a CD-ROM. In essence, these programs present a geologic map in a digital format that stresses ease of use and accessibility. This article describes DDM-SVF, a prototype dynamic digital map, developed by the author for use on the Macintosh computer (a Windows driver should be available from Allegiant, who publish SuperCard, early in 1995 for use on DOS computers). DDM-SVF displays four thematic geologic maps of the Springerville volcanic field, a late Miocene to Pleistocene volcanic field in east-central Arizona; a hard-copy version of these maps will soon be published as a U.S. Geological Survey Miscellaneous Investigation Series Map (Condit and others, in press). DDM-SVF is a major expansion of both SuperMap7/23/92, which included only a small part of the field, and of the four hard-copy thematic maps, by including a large petrologic data base and digital photographs. I hope this article points the way toward what is possible in the development of digital maps and inspires others to produce such maps; DDM-SVF barely scratches the surface. A demonstration version DDM-SVFDemo-v.xx.xx.94 can be obtained by anonymous FTP from eclogite.geo.umass.edu (IP address 128.119.45.20), in the directory "ccondit". The hardware needed to run DDM-SVF is a Macintosh with eight megabytes of random access memory, an eight-bit (256) color 13" monitor, a hard disk, and/or a CD-ROM reader. If a color printer is available, most figures and all maps can be printed in color. ATTRIBUTES OF DDM-SVF What DDM-SVF is and is not Several attributes differentiate DDM-SVF from map-making systems on desktop computers (for example, the Macintosh-based MiniCad-maps developed by the Canadian Geologic Survey (Peterson and Hanmer, 1992) and the DOS-based systems including GSMAP (Selner and Taylor, 1991) and those of Ambroziak and Cook, 1993.) First, it is a stand-alone application, that is, one needing no other software to run. Second, it was designed by a geologist with the intent of making the map and data as intuitively and easily accessible as possible; all maps, images, text, and data can be viewed, saved, or accessed by simple click or click-and-drag commands with the mouse. Third, this is not a map-making system. It is a map "presentation-manager," that is, a program designed to take already completed digital maps, and, with a minimum of reformatting, put them in a package that maximizes their accessibility to the user. The DDM-SVF program vesus the data in the program A clear distinction between what is the program that contains and presents the map (written using a hypermedia programming language) and what is the map and data within the program may perhaps best be made by analogy. A casual reference to the hard-copy (read "paper") map on which DDM-SVF is based (I-2431) probably refers to all four map sheets, including the maps, text and data found on the paper within the brown envelop into which the "whole map" is inserted. To be a purest, the actual map is the colored "cartoon", complete with contacts, unit and sample labels, that is overlaid on the topographic base. The rest is accomanying figures, tables and text. In this analogy, the program, created with SuperCard, is the "paper background" on which the digital map is "printed". For example, the programmer may create a card within a window into which she decides to put a map. In this case, the map has been created outside the SuperCard program using a computer aided drafting program (for example, Canvas). The programmer then pastes this map into the appropriate card in the SuperCard program. Likewise the programmer may create a another card and window into which he decides to insert a figure or another card into which he inserts the map's introductory text. From here the distinction between what is the program and what is inserted into the program blurs, because the SuperCard program, instead of being a "dumb" white piece of paper onto which the map pieces simply sit inert, can provide these pieces with an interactive link to other parts of the digital map. The programmer, anticipating that the geologist might want to know what the map symbol Qbb2 stands for, gives that symbol a script that says, in effect "when clicked on, go find your unit description (stored elsewhere in the program) and display it on the screen". Similar "hypermedia" links are provided throughout the program to map labels, text and tables after they are inserted into the SuperCard framework; many are also programmed into the framework (that is, the windows and cards of the program). Because scripts for a type of map label (for example map unit symbols) can be identical, and are easily assigned to each label, building such links is efficient, once each label has been assigned an identity (that for the map unit above is simply assigned the name "Qbb2"). Windows Within DDM-SVF DDM-SVF is a presentation-manager program that provides a series of windows, each containing some component of the map. The program allows the geologist to navigate between and within these windows. The first window (Fig. 1) is the hub, which is always displayed by default on the screen; it contains an "Index Map." To see a part of the detailed map, the user points and clicks at the appropriate place on the Index Map, which closes the Index Map window, and opens another window (the "Map Window") containing the designated segment of the map (Fig. 2). The user can scroll around the map within the window, a feature common to all windows in the program in which the information in the window might exceed the window's size. When done, the user closes the Map Window by clicking a "close box" on the window, causing the Index Map to reappear. The Map Window actually contains 24 cards, each containing one map segment, but displays only one card at a time. The reason for dividing the original map into overlapping segments is to accommodate computers with only 8 megabytes of random-access memory, because loading too big a map segment would cause "out-of- memory" problems. Menus and the Introductory Text window The program has Menus that enable the user to access additional windows not directly associated with the map proper. For example, one Menu entitled "Correlation of Map Units" presents the user with a list which opens a window containing any one of the map's 23 Correlation of Map Units charts. Another Menu, "Geologic-Summary," also provides the user with a list of selections. The selection "Introductory Text" opens a window containing the equivalent to a hard-copy map's summary text. Figures and tables can be called up by clicking on bold-faced words in the text (e.g. table.1). The Introductory Text window, as in any word-processor program, has "Search and Find" capabilities, and its text can be saved to an ASCII disk file. As the preceding suggests, DDM-SVF contains all information normally associated with a hard-copy color map, including the explanation of map symbols, correlation diagrams, summary text (including associated figures and tables), unit descriptions, and more. The Map Window The hypermedia programming built into the maps of the Map Window simplifies finding samples (or units), makes information on a map feature instantly available, and allows sequential changes in thematic map type. Finding sample locations and map units There are two methods for locating a map label denoting a sample location or map unit (equivalent to the "search-and-find" in a word processor program). Using the first method, the user clicks on a "Find" button displayed on a floating palette window, and types in the desired label (Fig. 2). The program then centers the map segment on that label; a circle surrounds the feature, and the label blinks. The second method for finding labels is provided from the Access-Windows Menu, using the "Show Access to Units/Samples All Areas" selection. This activates a pop-up window with buttons which display a list of labels (sample lists include major-element chemistry, paleomagnetic data and K-Ar data). A click on the wanted label in this "click-list" causes the program to locate the feature on the map. The order of samples on a list can be changed "on the fly," by clicking a "sort" button to sort the list alpha-numerically either by sample number or by associated map unit. Similar "click-lists" are available for displaying less comprehensive data sets, such as isotope, trace-element or mineral chemistry. Displaying unit descriptions and analytical data When a map segment is displayed, all map labels shown in bold print serve as "buttons." Clicking on any of them extracts the associated data from a hidden data field and displays it in a small pop-up window. A click on a unit symbol immediately displays that unit's description; likewise, a click on a sample label shows its major- element chemical analysis. These windows can be dragged around the screen to better see the map. This type of information can also be called to screen by clicking on a "Get" button, superposed on the map in a floating palette window, and typing the wanted label into the pop-up window called up by the "Get" button. Additional links allow one to display major-element chemistry by clicking on the sample identification as listed in the unit description's pop-up window (also a floating palette) or by clicking on the "Get Chem" button in that same unit window to display all chemistry for a given unit. Displaying digital photographs Additional "buttons" on map segments give access to digital photographs of geologic features of interest (Fig. 2). These buttons are small purple circles with the photo number, and an arrow showing the direction of view (41 and 42 on Figure 2), which can be displayed or hidden by a control from the Access-Windows Menu. A click on one of these buttons closes the map window and opens a "Photograph" window with the photo (Fig. 3). Photos include a caption and labels, which can be hidden to view the photo without clutter. A button on the photos allows each to be saved to disk. Where several photos exist for a given feature (e.g., an oblique aerial and a ground- based photo), a button embedded in each photo calls up the associated photo (after closing the previous one), and buttons on that photo allow return to the original photo. A "Digital Photograph Index Map," accompanied by "click-list" describing all photos, can be called up from the Geologic-Summary Menu to provide alternative access to the photos. Photomicrographs of each lithologic classification (and four xenoliths) can be accessed through the "click-list" associated with the Digital Photograph Index Map, from figures describing the lithologic types, or from any map segment where a round gray button similar to those for photos indicates a photomicrograph exists for a sample. Changing thematic map types One of the most useful features of DDM-SVF is its ability to depict thematic attributes while viewing a map segment by simply clicking a button in a floating palette. The Springerville thematic maps consist of four types (Fig. 4): a lithologic map, wherein all 409 volcanic units are assigned (and color coded) to one of 13 lithologies, based on mineral type and abundance; a geochemical map, wherein units are assigned to one of nine geochemical classes; an age map, in which volcanic units are assigned to one of five age groups; and a magnetopolarity map, wherein volcanic units are assigned to one of three polarity groups. Appropriate thematic map keys can be displayed for each map type. When changing map type, an additional change takes place: samples appropriate to the new thematic map type are made visible, and samples that were relevant to the previous map type are hidden. For example, when changing from a lithologic or chemical map (where chemical sites are plotted), to a paleomagnetic map (where paleomagnetic sample sites are plotted) the chemical sites disappear, and the paleomagnetic sample sites appear. Saving Data From DDM-SVF To ASCII Files One of the most important facets of this program is that all data can be made accessible outside the program itself for further use. A wealth of data exists in this program, all of which can be saved to disk file: unit descriptions for 409 units; over 600 major-element analyses; 215 XRF and DCP trace-element analyses; 103 neutron activation analyses; 57 Sr, 21 Nd and 33 Pb isotopic analyses; 41 K-Ar analyses, and data for over 180 paleomagnetic sites. All chemical and paleomagnetic data are saved in tab-delimited ASCII files, which can be directly imported into spread-sheet or word- processing programs for modeling and further use. All map segments and correlation charts for each segment can be saved as Pict format files, which can be opened by most CAD programs. Because these Pict files preserve all vector and raster file formats, and most CAD programs can convert them to DXF files, they be imported into geographic information systems (GIS) such as Arc/Info. In addition all map segments can be printed in color; this capability has been tested with HP Deskwriter C and HP Paintjet XL300 printers. The DDM-SVF Overview - A Built in Tutorial Although care has been taken to lay out the program in a logical format, equal importance has been attached to familiarizing the user with the program. This encapsulated look at the program can be found in the "DDM Overview" window, accessed through the Apple Menu, using the "DDM Overview" selection. This Overview gives step-by-step instructions to the user about how the eight different major window types are activated (figure 1 is the first page of this window), and delineates what is available in each. A click on any of the eight parts of this first page brings up an associated page with more detailed information on that topic. PROGRAM VERSIONS The CD-ROM contains three different versions of DDM-SVF to meet different users' needs; all are stand-alone applications, needing no other software to run. The first is the full-blown 35 megabyte program; this includes all the features described above. The second version includes no digital photos; its size is 12 megabytes. The last version is a "demonstration" program of 7 megabytes size; it contains all features the other programs do, but includes only three of the 24 map segments (and their associated unit descriptions, chemical data, and correlation charts), and seven photos. The "demo" program can be archived and stored on three 1.4-MB diskettes. CONCLUSIONS Dynamic digital maps can include a far broader range of material than can hard-copy maps, thus enhancing their scientific usefulness. And, because of the ease of access such hypermedia programs afford, a wide range of audiences can be reached in one package. For example, a "hard-core" petrologic modeler or Petrology 320 class may want to examine and extract the isotopic and trace-element data only, and have no interest whatsoever in the aerial photos. An interested layman, beginning geology student or geomorphologist on the other hand, might find them extremely interesting. Each can pick what to look at - with CD-ROM disk space, program size is no object (yet...) - and programs can be structured to make wading through unwanted information avoidable. Those interested in "rolling their own" DDM should examine the "Digital Map Making" section found in the DDM-SVF program - the bottom line is that with a little knowledge of SuperCard, most people should be able to make such a program. An examination of the script in these programs should help; because SuperCard runs in an interpreted mode, all code and parts of any stand-alone program can be loaded into the SuperCard editor, examined, and the process stepped through, and modified. It is hoped that making maps of this type will be of special interest to graduate students who have produced high quality, data -intensive map-based research which they find difficult to distribute, and to workers in multi-discipline research projects who need to make their data available to their colleagues. This type of program should not be viewed as a substitute for map-making systems, GIS, nor for hard-copy maps, each of which has its own valuable place in geologic research. The maps and data in this "presentation-manager" program can, however, be printed out on desktop printers, and all data saved from the program to tab-delimited ASCII format for other use. Future maps of this type offer a venue for workers who find it difficult to publish high-quality color maps and associated data quickly and efficiently. They also can be distributed electronically (for example by Internet), or on disk (either diskettes or CD-ROMs). Because of the digital format, one can include a large quantity of data with the map, something difficult to do with even the most complete analog maps. Further, because of the ability to save data from programs of this type into ASCII format files, these data need never be typed into digital form again, making the data easily accessible and accurately transferable to other workers. ACKNOWLEDGMENTS Much of the work on this paper and the associated programs was carried out while I was working for the U.S. Geological Survey's Branch of Astrogeology in Flagstaff Arizona. I appreciate very much the support of Larry Soderblom in "fronting" for me on this project. I also thank Glenn Bennett, a former USGS employee, with whom I shared many a dwebe-crazed evening kibitzing on how to make the program more robust and usable. George Drake of the Biology Department at the University of Massachusetts also supplied insights and encouragement in this work. Matt Neutra and I taught each other object-oriented programming as we generated SuperMap7/23/92 at UMass (one hell of a senior research project, Matt!). George Ulrich provided key encouragement in his enthusiasm for this project, and many useful suggestions and editing. Reviews by Dave Schleicher, Laurie Brown and Karen Mullaney were appreciated. REFERENCES CITED Ambroziak, R.A., Cook, C.A., 1993, Data, software and applications for educational and research in geology, U.S. Geological Survey Open File Report 93-231, CD- ROM. Condit, C.D., in review, DDM-SVF: Prototype color digital maps with ancillary data for the Macintosh computer (including lithologic, age-group, magnetopolarity and geochemical maps of the Springerville volcanic field, east-central Arizona and all major- and trace-element chemical and Sr, Nd and Pb isotopic and paleomagnetic data and 74 digital photographs), CD ROM; v. 8.23.94 size: 35 megabytes. Condit, C.D., and Neutra, Matthew, 1992, SuperMap7/23/92: A prototype dynamic digital map, in U.S. Geological Survey Open File Report 92-416, compiled by Dave Trout, Christine Cook, and Gregory Coats, Joint Education Initiative Sampler, CD ROM, 2.6 megabytes. Condit, C.D., Crumpler, L.S., and Aubele, J.C., in press, Lithologic, age, geochemical and paleomagnetic maps of the Springerville Volcanic Field, east-central Arizona, U.S. Geological Survey Miscellaneous Investigation Series Map, I-2431, 4 sheets. Peterson, T.D., Hanmer, S., 1992, Digital cartography with the Macintosh computer, in and out of the field, Current Research, Part E, Geological Survey of Canada, Paper 92-1E, p. 1-12. Selner, G.I, Taylor, R.B., 1991, GSMAP system VII, Geological Survey Open File Report 91-1.
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