LIDAR AND LANDSCAPES: EXAMPLES AND STRATEGIES APPLIED FOR GEOLOGIC MAPPING INVESTIGATIONS IN NEW YORK STATE

Like many states in the Great Lakes Region that have experienced multiple glaciations New York State has a diverse and complex landscape composed of unconsolidated landforms and deposits draped over an equally complex and variable bedrock surface. Over the last four years the New York Geological Survey has been actively implementing LIDAR data for mapping and geologic investigations. While the primary focus has been utilization on surficial geologic mapping and geomorphology, many other applications have manifested themselves.

The unprecedented resolution of terrain models constructed from LIDAR data has aided significantly in the identification of subtle Late Pleistocene landforms. These include many features that may only have as little as one meter of relief on the landscape such as ice marginal positions, ice walled lake plains, meltwater flow paths, shoreline and near shore deposits. In other locations the high resolution data allows for comparative geomorphic analyses of landscapes and paleo-ice flow reconstructions or isostatic corrections.

Similarly high resolution data provides an increased efficiency in identification of geologically sensitive terrains that include features associated with karst, landslides and solifluction. Recent hurricanes resulted in extreme flooding and landslide activity in numerous NY communities. Civic leaders are increasingly recognizing the need for detailed geologic maps to identify problematic locations and guide planning practices. LIDAR data sets coupled with detailed geologic maps provide a blue print to address geologic hazards.

LIDAR provides the resolution to develop tailored research strategies to address specific geologic questions. Familiarity with LIDAR and newly recognized glacial landforms has allowed the development of our “first trap hypothesis” to guide the detection and sampling strategies for determining coring locations with higher likelihood of having preserved datable materials to improve age constraints. Similar strategies have been developed to recognize potential locations for aggregate extraction operations. LIDAR data has revolutionized and greatly improved efficiency and geomorphic interpretation of geologic mapping in NY.