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Site content related to keyword: "sea level"

Regional partners to focus on sea-level rise in Delaware

A new partnership of scientists and federal officials from Delaware to Virginia will take a regional look at sea-level rise and how best to prepare for the impacts, including shoreline loss and increased flooding from storms.

Protecting tidal wetlands - UD scientists study tidal flow, sediment movement in Kent salt marsh

Three University of Delaware scientists are studying tidal water flow and sediment movement in a Kent County salt marsh to better understand changes to the marsh ecosystem due to a rising sea level.

Critical tide monitors face full shutdown

Caught in a federal-state funding standoff that one Delaware official said could put lives at risk, widely used public tide and weather monitors at more than 10 Delaware River and Bay sites face shutdown by September.

The National Oceanic and Atmospheric Administration posted the shutdown notice with little fanfare for its local Physical Oceanographic Real-Time System (PORTS) sites. Few outside of river and bay maritime interests were aware of the threat on Thursday.

Losing ground - Can marshes keep pace with the rising tide?

Marshes reduce storm flooding, filter contaminants out of water and provide habitat for birds, fish and other wildlife. However, these environmentally critical areas have decreased in extent along the coast in recent decades, and UD researchers are working to better understand the factors that affect marsh stability—especially in the face of sea level rise.

Hurricane Sandy Q&A - Experts at UD aid state, National Weather Service during storm

4:37 p.m., Oct. 31, 2012--The Office of the State Climatologist and the Delaware Geological Survey (DGS), both based at the University of Delaware, provided the Delaware Emergency Management Agency (DEMA) and the National Weather Service with weather, coastal flooding and stream flooding information for Delaware during Hurricane Sandy.

Gauging sea-level rise in marshes

Gauging sea-level rise in marshes

Global sea-level rise and sinking land are combining to cause water levels near Bowers Beach, Del., to climb at a rate faster than anywhere else on the Atlantic coast. Surrounding wetlands may change into mudflats if wetland elevation cannot keep pace with rising sea level. Sea Grant researchers Jack Puleo and Thomas McKenna are conducting field research in Kent County to increase our understanding of how marshes respond to sea-level rise. The work could help natural resource managers monitor marsh stability and predict future changes.

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

DGS Geologic Map No. 16 (Fairmont Rehoboth Beach Quadrangles) Dataset

This vector data set contains the rock unit polygons for the surficial geology in the Delaware Coastal Plain covered by DGS Geologic Map No. 16 (Fairmount and Rehoboth Beach quadrangles). The geologic history of the surficial units of the Fairmount and Rehoboth Beach quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

To facilitate the GIS community of Delaware and to release the geologic map of the Fairmount and Rehoboth Beach quadrangles with all cartographic elements (including geologic symbology, text, etc.) in a form usable in a GIS, we have released this digital coverage of DGS Geological Map 16. The update of earlier work and mapping of new units is important not only to geologists, but also to hydrologists who wish to understand the distribution of water resources, to engineers who need bedrock information during construction of roads and buildings, to government officials and agencies who are planning for residential and commercial growth, and to citizens who are curious about the bedrock under their homes. Formal names are assigned to all rock units according to the guidelines of the 1983 North American Stratigraphic Code (NACSN, 1983).

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

GM16 Geologic Map of the Fairmount and Rehoboth Beach Quadrangles, Delaware

The geologic history of the surficial units of the Fairmount and Rehoboth Beach quadrangles is that of deposition of the Beaverdam Formation and its subsequent modification by erosion and deposition related to sea-level fluctuations during the Pleistocene. The geology reflects this complex history both onshore, in Rehoboth Bay, and offshore. Erosion during the late Pleistocene sea-level low stand and ongoing deposition offshore and in Rehoboth Bay during the Holocene rise in sea level represent the last of several cycles of erosion and deposition.

B10 Salinity of the Delaware Estuary

B10 Salinity of the Delaware Estuary

The purpose of this investigation was to obtain data on and study the factors affecting the salinity of the Delaware River from Philadelphia, Pa., to the Appoquinimink River, Del. The general chemical quality of water in the estuary is described, including changes in salinity in the river cross section and profile, diurnal and seasonal changes, and the effects of rainfall, sea level, and winds on salinity. Relationships are established of the concentrations of chloride and dissolved solids to specific conductance. In addition to chloride profiles and isochlor plots, time series are plotted for salinity or some quantity representing salinity, fresh-water discharge, mean river level, and mean sea level. The two major variables which appear to have the greatest effect on the salinity of the estuary are the fresh-water flow of the river and sea level. The most favorable combination of these variables for salt-water encroachment occurs from August to early October and the least favorable combination occurs between December and May.

Geologic History of the Delaware Coastal Plain

In Delaware, the oldest unit of the Atlantic Coastal Plain is the Potomac Formation. Sediment eroded from the Appalachian Mountains was deposited in rivers and swamps in a tropical climate along the margins of the forming ocean during the latter part of Early Cretaceous time, about 120 million years ago.