Building National Spatial Data Infrastructures

A Window to the National Geologic Map Database (NGMDB) Map Catalog via ArcGIS Image Server

—Christopher Garrity, US Geological Survey

The AASG-USGS National Geologic Map Database, through its Geoscience Map Catalog, provides access to >89,000 maps and reports by >630 publishers. More than 23,000 of these publications are geologic maps. Access to these geologic maps and other types of geoscience reports is provided via the Catalog's Product Description Pages (PDPs) and its links to sales offices, libraries, and web servers where the products can be downloaded. Through the Catalog's ImageViewer, which is linked from the PDP, scanned copies of maps can be viewed quickly and directly in the user's Web browser (based on Lizard-Tech's ExpressServer and MrSID images). When the ImageViewer application was initiated in 2003, a prototype was developed for displaying all of the available geologic maps on a Web map, with a query function to identify the map and link to the PDP (Soller and Berg, 2003; Wardwell and others, 2003). At that time, the technology was not sufficient to provide the service that users expected, and so it was temporarily set aside. The prototype shown here is a renewal of that general concept, using the ArcGIS Server Image Extension by ESRI. The extension is used to provide access to geologic maps for:

1. users of ArcGIS, who can directly link to our Web Service; and
2. the general public, who will gain access via a map viewer in the NGMDB Map Catalog web pages.

This summer, production work begins on this initiative, refining the workflow, georeferencing maps, managing the map images within the Catalog's Oracle database, and preparing the website for public access to the REST service. This work has been accomplished in collaboration with the Wyoming Geological Survey and ESRI.