The geology and hydrology of the area between Wrangle Hill and Delaware City, Delaware, have been the focus of numerous studies since the 1950s because of the importance of the local groundwater supply and the potential environmental impact of industrial activity. In this report, 490 boreholes from six decades of drilling provide dense coverage, allowing detailed characterization of the subsurface geologic framework that controls groundwater occurrence and flow.
Delaware Geologic Research Symposium 2013
The Delaware Geological Survey is hosting a research symposium consisting of presentations related to geologic programs and research in Delaware. This meeting is targeting geoscience professionals as well as planners, engineers, and others that use geologic data. Documentation for PG or other applicable continuing education credits will be made available for those attending.
Our symposium will feature talks by the DGS staff on recent and ongoing research. Topics include modeling the impacts of wastewater irrigation on groundwater quality, new techniques for determining submarine discharge of groundwater and sea level issues, stratigraphy of the Potomac Formation, and geologic mapping in Sussex County.
Hurricane Sandy was a major storm event for the tidal areas of Delaware. As a part of the mission of the Delaware Geological Survey, we have compiled preliminary data related to Delaware tide and stream levels related to the Hurricane Sandy and compared them with previous flooding records.
The United States Geoscience Information Network (USGIN) initiative is the product of a partnership between the Association of American State Geologists (AASG) and the United States Geological Survey (USGS) created to facilitate discovery of, and access to, geoscience information provided by state and federal geological surveys of the United States. DGS has entered into a partnership with the Arizona Geological Survey (AZGS) to participate in USGIN by establishing a metadata clearinghouse node for Delaware.
Delaware and surrounding areas experienced an earthquake event on the afternoon of Tuesday, August 23, 2011. According to the US Geological Survey, a magnitude 5.8 earthquake struck at 1:51 p.m. in central Virginia, in an area referred to as “the Central Virginia Seismic Zone” because of its relatively active earthquake activity for the region. The epicenter was located five miles south-southwest of Mineral, Virginia, with the quake was focused at a depth of 6 km (3.7 miles) below the surface (http://earthquake.usgs.gov/earthquakes/recenteqsww/Quakes/se082311a.html). The Virginia Geological Survey reports that this is the largest Virginia earthquake known in historic times. A few small aftershocks have occurred in the hours afterward.
The Delaware Geological Survey (DGS) currently monitors groundwater levels in a network of 68 wells in Delaware. Long time-series of water levels in major aquifers serve as critical baseline data for resource management and analyses of aquifer response to pumping, climatic variability, drought hazards, seawater intrusion, and interaction with streams and their ecosystems.