Cost of 1:12,000-scale geologic map; $500,000: cost of 3D data, priceless

In the Seattle, Washington area (Figure 1), new derivative maps are facilitating planning, engineering, research, and outreach to a greater user population than ever before. This resurgence is due in part to a more informed user base and in part to having more useful map products. Multi-agency collaboration and funding have supported the building of a database of subsurface geologic data, the preparation of new digital geologic maps, and many new derivative maps. Geologic maps and borehole data are available to partners on agency intranets via interactive programs, to the public over the Internet using ArcIMS, and to onsite visitors using GeoMapNW’s computer lab. The new maps and geodatabase provide information such as regional geologic context for subsequent site-specific investigations, extent of fill, thickness of geologic layers, rapid scanning for specific geologic settings, and depth to groundwater, and they also enable quick cross section construction.