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Site content related to keyword: "coastal geology"

OFR37 Summary Report: The Coastal Storm of December 10-14, 1992, Delaware and Maryland

OFR37 Summary Report: The Coastal Storm of December 10-14, 1992, Delaware and Maryland

On December 10, a low pressure system moved rapidly north-northwest from eastern North Carolina and Virginia, up the Chesapeake Bay to a position just west of Chestertown in Kent County, Maryland by 0700 on December 11. The system then moved irregularly to the southeast, stalled for several hours over Georgetown, Delaware, and proceeded offshore early on December 12. Approximate locations of the storm's track are shown on Figure 1. The storm had associated rain that contributed to some local stream flooding and high winds that created strong surf and waves. The waves were compounded by an astronomical high tide (full moon) to produce coastal flooding along Delaware Bay and some breaching of the dunes along the Atlantic coast. The position of the storm offshore blew north-northeast winds onto the coast and abnormally high tides continued through December 15.

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OFR36 Summary Report: The Storm of January 4, 1992

OFR36 Summary Report: The Storm of January 4, 1992

On January 4, 1992 an intense storm moved from the east across the Delmarva Peninsula and the Chesapeake Bay. Its track was the result of the low pressure being pulled westward by a strong cold-cored upper low moving across Georgia and South Carolina. The storm exhibited tropical/subtropical characteristics on radar. Satellite photos indicate that an "eye" to the storm formed just prior to landfall. Landfall occurred over the southern Delmarva Peninsula just prior to the time of high tide (0648 at Ocean City, Md). The storm weakened rapidly as it moved over land areas with a secondary area redeveloping farther out to sea later in the day on the 4th. Approximate locations of the storm's track are given on Figure 1. As the storm moved across the Delmarva Peninsula perpendicular to the coast, Delaware was in the right-foreward quadrant to the north of the "eye" of the storm. This position typically produces the highest winds associated with a tropical storm. These winds created high waves that in conjunction with an astronomical high tide (new moon) produced strong surf and abnormally high tides along the shore. Rainfall from the storm in Delaware was not heavy enough to cause flooding of streams. Coastal flooding of marshes and low-lying areas did occur along the Inland Bays and along Delaware Bay.

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SP26 Historical Coastline Changes of Cape Henlopen, Delaware

SP26 Historical Coastline Changes of Cape Henlopen, Delaware

Coastlines are not static features. They are shaped by the daily effects of wind, current, and wave activity. Over time, a coastline may move landward due to relative sea-level rise or low sediment supply, or seaward due to relative sea-level fall or an overabundance of sediment. Perhaps the most striking example of shoreline movement in Delaware is at Cape Henlopen which has grown northward approximately one mile in the last 160 years. Maps and aerial photographs show these changes.

Coastal Plain Rock Units (Stratigraphic Chart)

The geology of Delaware includes parts of two geologic provinces: the Appalachian Piedmont Province and the Atlantic Coastal Plain Province. The Piedmont occurs in the hilly northernmost part of the state and is composed of crystalline metamorphic and igneous rocks. This chart summarizes the age and distribution of the geologic units that are recognized in the state by the Delaware Geological Survey.

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.

The Geology of Delaware

The Geology of Delaware is an online resource for information about the geology and hydrogeology of Delaware. Information on these pages is explained in general terms although common geologic terminology is used. This book covers the major important factors in Delaware geology as well as latest research. Additional information is provided at the bottom of some pages and on the last page of the book, More Information.

RI17 Ground-Water Geology of the Delaware Atlantic Seashore

RI17 Ground-Water Geology of the Delaware Atlantic Seashore

The need for locating additional sources of ground water for the Delaware Atlantic seashore, a predominantly recreation-oriented area, is indicated by an expanding population in the belt between Philadelphia, Pennsylvania and Washington, D.C., combined with increasing leisure time. Present water use in the shore area is approximately 4 million gallons per day and will reach 9.3 million gallons per day by the year 2000. A new geologic interpretation of the occurrence of deep aquifers in the Delaware Atlantic seashore area is presented. Recent data from deep wells has enabled the construction of a more accurate geologic framework upon which the hydrologic data are superimposed. Correlation of Miocene sands concludes that the Manokin aquifer lies at greater depths in southeastern Delaware than previously thought.

EPSCoR seed grants awarded to environmental researchers

Tom McKenna measuring subsurface temperature along the shoreline of Indian River in Sussex County, Delaware. Photo by Doug Miller

With a focus on environmental issues important to the state, the Delaware National Science Foundation Experimental Program to Stimulate Competitive Research (NSF EPSCoR) office has awarded five seed grants to investigators whose projects aim to solve environmental problems in Delaware.

DGS Publications

The core of much DGS work culminates in the release of data and findings in official DGS publications, including Open File Reports, Reports of Investigations, Geologic Maps, Hydrologic Maps, and Bulletins.

DGS issues report on the geology of Bethany Beach

RI75 Stratigraphy And Correlation Of The Oligocene To Pleistocene Section At Bethany Beach, Delaware

The Delaware Geological Survey (DGS) at the University of Delaware released a report that provides new insights into the underground geology and hydrology of southeastern Sussex County, Delaware. The report, "Stratigraphy and Correlation of the Oligocene to Pleistocene Section at Bethany Beach, Delaware," summarizes the results of geological investigations conducted on a 1,470-foot-deep research borehole drilled at Bethany Beach, Del.