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Site content related to keyword: "sea level rise"

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.

Finding faults - Delaware Geological Survey discovers evidence of past earthquakes

Delaware Geological Survey scientists found slickensides in core samples indicating faults in northern Delaware.

Delaware Geological Survey (DGS) scientists have uncovered hard proof of faults in northern Delaware, indicating the occurrence of earthquakes millions of years ago.

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.

DGS Participates in the Delaware Estuary Conference

Partnership for the Delaware Estuary

DGS researchers Tom McKenna and John Callahan presented some of their work at the Delaware Estuary Science and Environmental Summit at Cape May, NJ, and hosted by the Partnership for the Delaware Estuary.

A Coastal Flood Monitoring System for Delaware

Flooding at Kitts Hummock after the Mother's Day Storm 2008
Project Contact(s):

During the last two decades, storms such as Hurricanes Katrina and Ike along the Gulf of Mexico and Floyd and Hugo along the Atlantic Coast of the United States have resulted in significant loss of life, injuries, and property damages exceeding well over 100 billion dollars. Much of the damage associated with these and other tropical and extra-tropical weather systems is associated with severe coastal flooding. The purpose of this project is to develop a real-time coastal flood monitoring and warning system for the coastal communities in Kent County, Delaware. This system will serve as a prototype for similar early-warning systems, which may then be applied along the entire Delaware coast.

RI76 Stratigraphy, Correlation, and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware

RI76 Stratigraphy, Correlation, and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware

Rising and highstands of sea level during the middle to late Pleistocene deposited swamp to nearshore sediments along the margins of an ancestral Delaware Bay, Atlantic coastline, and tributaries to an ancestral Chesapeake Bay. These deposits are divided into three lithostratigraphic groups: the Delaware Bay Group, the Assawoman Bay Group (named herein), and the Nanticoke River Group (named herein). The Delaware Bay Group, mapped along the margins of Delaware Bay, is subdivided into the Lynch Heights Formation and the Scotts Corners Formation. The Assawoman Bay Group, recognized inland of Delaware’s Atlantic Coast, is subdivided into the Omar Formation, the Ironshire Formation, and the Sinepuxent Formation. The Nanticoke River Group, found along the margins of the Nanticoke River and its tributaries, is subdivided into the Turtle Branch Formation (named herein) and the Kent Island Formation.

Delaware Bay Group deposits consist of bay-margin coarse sand and gravel that fine upward to silt and silty sand. Beds of organic-rich mud were deposited in tidal marshes. Near the present Atlantic Coast, the Delaware Bay Group includes organic-rich muds and shelly muds deposited in lagoonal environments.

Assawoman Bay Group deposits range from very fine, silty sands to silty clays with shells deposited in back-barrier lagoons, to fine to coarse, well-sorted sands deposited in barriers and spits.

Nanticoke River Group deposits consist of coarse sand and gravel that fine upward to silty clays. Oyster shells are found associated with the clays in the Turtle Branch Formation. Organic-rich clayey silts were deposited in swamps and estuaries. Well-sorted fine sands to gravelly sands were deposited on beaches and tidal flats on the flanks of the ancestral Nanticoke River and its tributaries.

The Lynch Heights, Omar, and Turtle Branch Formations are age-equivalent units associated with highstands of sea level,which occurred at approximately 400,000 and 325,000 yrs B.P. (MIS 11 and 9, respectively). The Scotts Corners, Ironshire, Sinepuxent, and Kent Island Formations are age-equivalent units associated with highstands of sea level, which occurred between 120,000 and 80,000 yrs B.P. (MIS 5e and 5a, respectively).

DGS issues report on the surficial geology of southern Delaware

Report of Investigation 76

The Delaware Geological Survey (DGS) has released a new technical report entitled Stratigraphy, Correlation, and Depositional Environments of the Middle to Late Pleistocene Interglacial Deposits of Southern Delaware.

Delaware Geological Survey Radiocarbon Database

Delaware Geological Survey Radiocarbon Database

Radiocarbon dates from 231 geologic samples from the offshore, coastal, and upland regions of Delaware have been compiled along with their corresponding locations and other supporting data. These data now form the Delaware Geological Survey Radiocarbon Database. The dates range from a few hundred years to approximately 40,000 yrs (40 ka) BP (before present). All dates younger than about 18,000 yrs have been calibrated using the method of Stuiver and Reimer (1993). A plot of the dates versus the elevations of the samples shows four distinct groupings: those associated with the rise of sea level during the Holocene, those from the uplands, those in modem stream valleys, and those older than the detectable range of present radiocarbon techniques. A fifth group of samples in the 20-38 ka range and from below present sea level are ambiguous and were previously used as evidence for a mid-Wisconsinan high sea stand (Milliman and Emery, 1968).

RI54 Radiocarbon Dates from Delaware: A Compilation

RI54 Radiocarbon Dates from Delaware: A Compilation

Radiocarbon dates from 231 geologic samples from the offshore, coastal, and upland regions of Delaware have been compiled along with their corresponding locations and other supporting data. These data now form the Delaware Geological Survey Radiocarbon Database.

Natural Hazards in Delaware

Hurricane Floyd - 1999

Natural hazards are those events in the physical environment that present risks to human life or property. The DGS identifies and investigates natural hazards to help understand the earth systems that present the hazards and determine strategies to prepare for or mitigate the risks. We are active in advising emergency management agencies on natural hazards, and are included in the Delaware Emergency Operations Plan as an agency having a vital role in dealing with floods, northeaster/extratropical storms, droughts, earthquakes, sinkholes, and dam failures.

OFR17 A Guide to Information on Benchmarks in Delaware

OFR17 A Guide to Information on Benchmarks in Delaware

To conduct an elevation survey, a surveyor needs a starting point for which the exact elevation above mean sea level is known. These starting points are called benchmarks. State and federal agencies install benchmarks throughout every State, creating a network of elevation points which covers the entire continental United States. These benchmarks are considered to be permanent, and usually consist of a brass, bronze, or aluminum disc about 4 inches in diameter mounted in a cement post or in a drill hole in a permanent foundation. Each benchmark also has the installing agency's name and an identification number stamped into it. In December of 1980 the Federal Emergency Management Agency (FEMA) allotted the State of Delaware funds to determine the number and condition of federal benchmarks and other elevation reference control points. The National Flood Insurance Program (NFIP), contained within FEMA, requires accurate flood surveys of property in flood-prone areas. An extensive and accurate benchmark network throughout the State is needed to help meet these needs.

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.