AGGREGATE RESOURCE RECONNAISSANCE MAPPING IN THE COASTAL PLAIN OF VIRGINIA

Resilience refers to a community’s ability to adapt to changes from increased hazards due to natural and anthropogenic forcings. Initiatives to better prepare municipalities and establish protective measures are a key focus in the Virginia coastal zone as the region experiences one of the highest rates of sea level rise on the East Coast. The Virginia Department of Energy’s Geology and Mineral Resources Program conducted a study of potential sand, gravel, and clay aggregate resources in a portion of the Coastal Plain. This one-year effort was funded in part by the Virginia Coastal Zone Management Program through a grant provided by the U.S. National Oceanic and Atmospheric Administration. The focus for this pilot phase of assessment is Virginia’s Middle Peninsula, which encompasses almost 900 thousand acres, with over a 1,000 miles of shoreline. Other efforts in states with significant glaciofluvial deposits guided our study; however, the geologic deposits in this region of the Coastal Plain are fluvial, estuarine, and marine in origin. We conducted a multiparameter geospatial analysis including the comparison of topographic, geologic, and soil maps, borehole data, occurrences of mine sites, textural data, and the presence of sensitive habitat such as wetlands. The majority of potential sand and gravel resources identified in study are within Pleistocene fluvial-estuarine terraces, extending into older Pliocene units. Clay resources are typically limited to Miocene lower Chesapeake Group marine units. These data can support resilience initiatives that were identified in the 2021 Virginia Coastal Resilience Master Plan, which include efforts to mitigate widespread habitat loss, impacts to critical infrastructure, and potential residential displacement due to increased coastal flooding. Planners and contractors who are interested in materials for elevating roads, shoring up existing structures, providing shoreline protection, and restoring wetland habitats can utilize the data to understand where potential resources may occur. The final products include a 1:100,000-scale aggregate resource potential map, geodatabase, and report for the Middle Peninsula which are available to the public. Additional efforts to expand to other coastal regions are ongoing.