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DATE: Dec. 16, 2005


NAME: Recording geographic coordinates in the MARC 21 Authority Format

SOURCE: George A. Smathers Libraries (University of Florida) and ALA/MAGERT Cataloging and Classification Committee.

SUMMARY: This paper suggests adding field 034 to authority records for geographic coordinates associated with places. This field would eventually form the basis for coordinates-based retrieval of all cataloged records containing those geographic terms.

KEYWORDS: Field 034; Coded Cartographic Mathematical Data; Geographic Coordinates, GIS



12/16/2005 - Made available to the MARC 21 community for discussion.

01/22/06 - Results of the MARC Advisory Committee discussion - Participants agreed that a proposal to define field 034 in the authority format will be presented at the next meeting with the following:

Discussion Paper 2006-DP01 : Recording geographic coordinates


Geographic Information Systems (GIS) may represent a new way of looking at information (to librarians, not necessarily geographers). Such systems integrate computer hardware, software, data, and the human mind to bring new perspectives to creative problem solving. As an emerging technology for libraries, GIS raises a host of issues. It can be costly, it can have a very steep learning curve, and it takes up a lot of computer space. At the same time, it is a very attractive technology that most proponents claim has revolutionized the way we look at the world and the way we can solve the issues of switching from print to digitization technology.

To solve problems using GIS, you must have information or data geo-referenced that can be layered with more data. Libraries are a significant source of such information, and the effectiveness with which libraries supply that information can do much to aid or hinder those attempting to solve problems using GIS.

"The traditional library has relied on author, title, and subject as the keys to its catalog. Although one might imagine using geographic location as a key, the technical difficulties associated with doing so in a traditional library are profound. But they are comparatively trivial in a digital library, and several WWW sites now support search of their information archives using geographic location as a primary key. A geolibrary is defined as a digital library that is searchable by geographic location, returning maps, images, reports, photographs, and even pieces of music identified with a particular location." Michael F. Goodchild, Professor of Geography at the University of California, Santa Barbara.

Spatial analysis can allow for geographical searches of library materials. Open systems architecture, application programming, and capability to support integration with other software allow application development to go with the greater demand placed on librarians to provide information. Geospatial information systems are entering the curricula of many school programs and it is well established as a subject of study at the college level. In academic library settings patrons from a variety of fields are coming together in their usage of GIS as a tool and in their need for the library to supply better access to information relevant to these many fields. Hence there is a need to use the new GIS technology effectively but not without the traditional skills of librarianship.

The library professional must: evaluate user needs, select data, prepare and catalog data for users, and design, serve and manage public services. GIS requires collaboration in the library and partnerships with outside entities, specifically geographers. An essential component of indexing digitized materials is geographic or spatial data coupled with geographic processing functions. GIS is trying to address the requirements of digital libraries, but also incorporate strategies for geographic and other database collaborative work besides library catalogs and including data mining. GIS will allow applications to exchange information and process retrievals. Spatial data will allow for viewing results in an informative and well-indexed manner. As libraries continue to digitize their collections and continue to find more and more things to digitize, they keep leaving a wealth of spatial information hidden due to limitations of current catalog and authorities systems. The challenge lies in using GIS to provide access to these materials/information. The ability to use GIS continues to grow for accessing static information and to interact with and manipulate data online. Librarians must work with geographers to take on more managerial roles in the design and provision of GIS services, perhaps leaving the technical aspects to specially trained geographers or "geolibrarians."

In library catalog records for maps and other cartographic materials, a pair of MARC fields, field 034 (Coded Cartographic Mathematical Data) and field 255 (Cartographic Mathematical Data), have long been used to unambiguously identify the location of a coverage area with geographic coordinates. In recent years online catalogs of some libraries have become able to use this data as a retrieval point for patrons. Generally these fields have seen very limited use in that they were used only when the coordinates actually appear on the cartographic item being cataloged and thus never on other formats of materials which may have significant value for layering of GIS data.


There are often difficulties in full and precise retrieval of relevant geospatial resources by patrons searching in library catalogs due to the limited ways that subject access for places has been provided. The inclusion of geographic coordinates on bibliographic records for cartographic materials is a valuable way of defining specific coverage, but this data is frequently omitted since it is not required by cataloging rules and since many maps do not display them.

Searching by geographic coordinates is offered as a mode of access by only a few library catalog systems vendors at this time, although it may be offered more frequently in the future. A document from the Functional Requirements for Bibliographic Records (FRBR) initiatives "Mapping MARC data elements to user tasks" lists the bibliographic 034 field coordinates subfields d-g as relevant to the user tasks of resource discovery of search, identify and select as well as the resource use task select. Coordinates in the field 255 subfield c are listed for the same resource discovery tasks. Inclusion of geographic coordinates will be helpful to eliminate ambiguity for non-unique place names such as "Big Creek" which must sometimes deviate from the normal state or country qualifier and use county. Use of coordinates can also help to clarify extent of large regions of continents, especially when the terms may appear inconsistently such as "Africa, North" and "Africa, Southern". It would also help when coverage area of a term such as "Southern Cone of South America" may not be popularly known. Use of language-neutral geographic coordinates can be a strong asset for international sharing of bibliographic information as well

2.1 Coordinates in Authority Records

In authority records for places, geographic coordinates have frequently been included in note fields (field 670) cited from authoritative sources to document the place name. However, because the data is recorded in a textual form and is not isolated, it would be difficult to utilize the information for a coordinates-based search in the context of the note. Repetition of the coordinates in a specific data field amenable to machine retrieval and compatible with other geographic database searching systems would offer the potential for patrons to better retrieve items concerning a subject place.

It would be appropriate to include coordinates in authority records, because it is important information about the entity described in the authority record. Since this is information about the place for which the authority record is made, one could argue that it belongs in the authority record, rather than in every bibliographic record that relates to that place. To use the data systems would need to be programmed to utilize such information by linking between bibliographic and authority records.

In the context of the bibliographic record these subfields record the specific coordinates given on the map or other geospatial resource; in the authority format the coordinates apply to the entity described and would be taken from a reliable source such as the USGS Geographic Names Information System (GNIS) record for the place or from a gazetteer.

In bibliographic records, coordinates also appear in textual form in subfield $c of the field 255. Typically a cataloger would transcribe the coordinates from a map being cataloged into field 255 subfield $c of the map record and then code the same data into the 034 field of the same record. The recording of the coordinates in these two fields differs in several ways. In the 255 field there are symbols for degrees, minutes and seconds which do not appear in the 034 field. The data in the 034 field is formatted and may be given either as decimal degrees, or as degrees, minutes and seconds with the presence of the decimal indicating which is used. The west, east, north and south hemispheres are indicated either with the first letter of the direction or by plus or minus. Coordinates in 255 field reflect the information as it is given on the item being described.

2.2 Possible Solutions

2.2.1. Field 034 in Authority Format. The MARC 21 Authority Format should be expanded to include coordinates and the likely field would be 034, already defined in the bibliographic format. Use of the coded field 034 is more desirable than the textual form in field 255 to record coordinates data associated with places because it is in a form more usable for coordinates-based machine retrieval.

The field should be repeatable and derived from authoritative sources, i.e. the U.S. Board on Geographic Names, which often gives lists of coordinates for places.

The current definition of bibliographic field 034 is as follows:

034 Coded Cartographic Mathematical Data (R)

      First - Type of scale
         0 - Scale indeterminable/No scale recorded
         1 - Single scale
         3 - Range of scales
      Second - Type of ring
         # - Not applicable
         0 - Outer ring
         1 - Exclusion ring
   Subfield Codes
      $a - Category of scale (NR)
         a - Linear scale 
         b - Angular scale
         z - Other type of scale
      $b - Constant ratio linear horizontal scale (R)
      $c - Constant ratio linear vertical scale (R)
      $d - Coordinates--westernmost longitude (NR)
      $e - Coordinates--easternmost longitude (NR)
      $f - Coordinates--northernmost latitude (NR)
      $g - Coordinates--southernmost latitude (NR)
      $h - Angular scale (R)
      $j - Declination--northern limit (NR)
      $k - Declination--southern limit (NR)
      $m - Right ascension--eastern limit (NR)
      $n - Right ascension--western limit (NR)
      $p - Equinox (NR)
      $s - G-ring latitude (R)
      $t - G-ring longitude (R)
      $6 - Linkage (NR)
      $8 - Field link and sequence number (R)

2.2.2. Appropriate subfields for authority record. Relevant data elements from field 034 in the MARC 21 Bibliographic Format include four subfields that define a bounding box (subfields $d, $e, $f, and $g). These are generally adequate for expressing the westernmost, easternmost, northernmost and southernmost extent of coverage of a map. Two more subfields ($s and $t) for G-ring latitude and longitude may also be used. The rest of the information included in field 034 applies to the manifestation (i.e. the resource described in the bibliographic record). The indicator values are also relevant only to the bibliographic record. In addition there may be a need for a date indicating the time period in which the coordinates are applicable (because geographic places may change boundaries over time) and an indication of the source of the information.

It is suggested that field 034 be repeatable in authority records either to indicate different geographic areas applicable to different periods of time or to record coordinates from different sources and possibly in different formats.

2.2.3. Application of field 034. Types of authority records that may benefit from the addition of coordinate data are records for place names, geographic features, and some subject headings such as battles, buildings, etc. It is clear that addition of this data in authority records would be a major undertaking, and it would need to be a cooperative project between the library and geospatial communities. It may be possible to extract the data from reliable sources.


Coordinate data taken from Minnesota Geographic Data Clearinghouse

Authority record for Minnesota: n 79021675

     035 -- ‡a (OCoLC)oca00255473
     040 -- ‡a DLC ‡b eng ‡c DLC ‡d DLC ‡d WaU
     043 -- ‡a n-us-mn
     151 -- ‡a Minnesota
     667 -- ‡a AACR 1 form: Minnesota.
     781 -0 ‡z Minnesota
     034 for the bounding box would be:
     034 -- ‡d W0975000 ‡e W0890000 ‡f N0495000 ‡g N0430000

Authority record for Todd County, Minn.: 81093353
     035 -- ‡a (OCoLC)oca00638538
     040 -- ‡a DLC ‡b eng ‡c DLC ‡d WaU
     043 -- ‡a n-us-mn
     151 -- ‡a Todd County (Minn.)
     451 -- ‡w nnaa ‡a Todd Co., Minn.
     781 -0 ‡z Minnesota ‡z Todd County
     034 for the bounding box would be:
     034 -- ‡d W0951400 ‡e W0946500 ‡f N0463800 ‡g N0457600


It is clear that there will be advantages to adding geographic coordinates in a specific data field to authority records for places. There are some issues that need to be discussed further regarding the addition of this data in authority records. These have emerged during discussion with MAGERT Cataloging and Classification Committee during the past year and on the SUBCOOR discussion list hosted at the Library of Congress. (For more about the Subject Coordinates Discussion List see:

While some of these issues may be resolved later by the bodies which govern choices of content of authority records, some should be determined before the usage of the data field becomes an option in the MARC 21 Authority Format in order to provide all the field options that may later be useful.

According to the Mapping Science Committee of the National Research Council in its 1994 report Promoting the National Spatial Data Infrastructure Through Partnerships, "The twenty-first century will see geographic information transported from remote nodes using computer networks to support decision making throughout the nation. ... Timely use of these data would be difficult due to ill-defined format, quality, and accuracy. National or regional decision making would be severely impaired because most data sets are not adequately characterized." Enhancing the power of authority records to better partner with the problem-solvers who use GIS to solve our problems is a worthwhile endeavor.

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