Reports
Metadata creation for the Maryland Geological Survey's collection of aerial photographs, Part 1 (2011-2012)
2012,Hennessee, E.L.; Shelton, D.
File Reports, Coastal and Estuarine Geology, FR 2012-07
Abstract
The Maryland Geological Survey (MGS or “the Survey”) shares the concerns of other agencies and organizations engaged in geological research – that geoscience collections and data are valuable in their own right, beyond the lifetime of the projects during which they are collected or acquired, and that special efforts are required to preserve them and ensure their accessibility.
In this, its fourth year as a recipient of a National Geological and Geophysical Data Preservation Program (NGGDPP) grant, MGS created metadata for three components of its collection of aerial photographs and associated index maps: (1) aerial photographs from the two earliest “eras” in its holdings, 1936-1938 and 1951-1953, (2) the second and final subset of enlarged (2’ x 2’) aerial photos flown in the 1950s and 1960s over the State’s barrier islands, and (3) the entire collection of index maps. The Survey supplied the metadata to the U.S. Geological Survey’s (USGS) ScienceBase Catalog, adding a total of approximately 7,600 new records.
Aerial photographs depict land use and land cover at particular points in time. A time-series of such photographs can reveal detectable, measurable changes in those patterns. Such photography is irreplaceable – once the flight date has passed, ground conditions on that date cannot be replicated or reconstructed. The Survey’s collection of aerial photographs will only grow in usefulness, as land use continues to change, and as a broad range of researchers and managers attempts to reconstruct past usage from these snapshots in time.
Aside from the inherent value of aerial photography, MGS selected the collection for documentation because: (a) it is one of the Survey’s most frequently used collections, (b) it is a permanent holding for which metadata are incomplete, (c) documenting the collection is the first of several steps that will eventually lead to the photos being scanned, uploaded to the Internet, and permanently preserved, (d) members of the Survey’s Data Preservation Advisory Panel unanimously recommended that this collection be the next one documented, (e) the project supports a statewide effort to create an electronic archive of historical aerial photographs, and (f) the existence of complete metadata may strengthen future proposals requesting funding for digitizing the photographs.
In the course of creating metadata for the collection, MGS found that (a) again, each collection is unique and poses its own set of issues to be resolved, in this case, how to group the collection components, (b) collaboration with other agencies, while fruitful, particularly in terms of avoiding duplication of effort, places additional demands on the cooperators, and (c) anticipating the end of the metadata-creation phase of data preservation, the Survey must begin directing its attention to collection accessibility.
MGS has now completed a collections inventory and created metadata for about one-third of its collections – the initial steps in building what it hopes will become a first-rate repository that effectively serves the larger geoscience community in Maryland and beyond.
