Spatial Predictive Models
Sometimes it is possible to predict the locations of cultural resources based on archaeological and geographic information already in hand. The predictive model at the left shows the high-probability areas (in green) for prehistoric sites in the Upper Clear Creek drainage system in central Ohio. The physical attributes of known prehistoric sites were used as the parameters in an algorithm that incorporated LiDAR-based complex terrain analysis and hydrological analysis to determine the areas of high-probability. By using the physical attributes of known sites (distance to water, relative elevation, slope, etc.), the predictive model is unique to the topographic setting, and gives the algorithm the flexibility to adjust its parameters to create a predictive model for any unique topographic setting. The predictive model is draped over a LiDAR-based digital elevation model.
Zonal Distance Viewshed
On some projects it is important to know what cultural resources are visible from/to a new construction. The example at left depicts the viewshed of a hypothetical tower in Pike County, Ohio. A LiDAR-based digital surface model, which includes trees and above ground structures, was used as the basis for the viewshed. The viewshed was further analyzed in zonal distances from the tower. The application of a viewshed can include multiple structures and encompass large areas that can be subdivided into multiple zones to determine the visual effects on historic properties. This would be important for characterizing the indirect effect on a cultural resource.
3D Surface Imagery
Producing life-like views of landscape features from the air is a useful tool for discovering important features and helping others better visualize what they look like. The 3D image provided here (left) of the Dungan Works (a small square earthwork with rounded corners) was created using an aerial photo draped over a digital surface model created with LiDAR data. The earthwork is located on a hilltop overlooking Jackson, Ohio. 3D surface imagery is a great way to show how geographic features fit into the landscape.
3D Urban Viewshed
3D viewsheds combined with 3D Surface Imagery and viewshed analysis is an excellent way to more realistically show the visual impact of an object on the landscape. 3D viewsheds are most applicable in urban settings. The image here (left) is of downtown Cleveland, and the viewshed is originated from the top of the Wolstein Center at Cleveland State University. The bright green areas all can be seen from the top of the Wolstein Center.