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Site content related to keyword: "Red Clay Creek"

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.

Common Rocks and Minerals of the Delaware Piedmont

The Red Clay Creek has flowed through the rolling hills of northern Delaware for many thousands of years, cutting a deep valley into the old deformed rocks of the Appalachian Piedmont. The Red Clay valley contains many of the common rocks found throughout the Delaware Piedmont.

Stream Station: Red Clay Creek near Stanton

USGS 01480015 RED CLAY CREEK NEAR STANTON, DE

Station Type: 
Stream
Period of Record: 
1988 to Present
Frequency: 
Monthly
Map County: 
New Castle County
Map Location: 
39.71575,-75.639944

Stream Station: Red Clay Creek at Wooddale

USGS 01480000 RED CLAY CREEK AT WOODDALE, DE

Station Type: 
Stream
Period of Record: 
1943 to Present
Frequency: 
Monthly
Map County: 
New Castle County
Map Location: 
39.762805,-75.6365

Outcrop Cc12-c: The Red Clay Creek Edge

Rock Outcrop Cc12-c: The Red Clay Creek Edge

Along the edge of the Red Clay Creek exists a large outcrop that extends out into the stream. This rock is part of the Wissahickon Formation, with pelitic facies, ½" elongated sillimanite nodules, and disharmonic folds. The compositional layering of this rock is 1/8 – ½" of biotite rich layers alternated with fine-grained psammitic layers (not quartz-feldspar layers). Some of these layers are sheared (shear zones). The sillimanite nodules, pegmatite pods, and shear zones in this rock are all parallel to fold axes. The axial plane of these folds is 20 degrees east of north, plunges 42 degrees northeast, and dips 90 degrees. Within this large outcrop are several 2-3' layers of “rock that rings” (when hit) and are folded with petitic gneiss. This pelitic gneiss shows more intense folding while the rest of the rock is gently folded. The “rock that rings” is also peppered with small lavender garnets.

B2 Geology and Ground-Water Resources of the Newark Area, Delaware with a Section on the Surface Water Resources

Geology and Ground-Water Resources of the Newark Area, Delaware with a Section on the Surface Water Resources

This report describes the geological and lithological conditions in the Newark area, and the occurrence, quantity, and quality of the available ground-water supply. Newark is located on the Fall Line, the boundary between the rolling hills of the Piedmont on the north and the gentle slopes of the Coastal Plain on the south. Because the Piedmont is underlain by dense crystalline rocks and their weathered clayey soils, which are of low water-bearing capacity in contrast to the more permeable silts and sands of the Coastal Plain, the exploration for ground water was confined to the Coastal Plain south and southeast of Newark.

SP20 Delaware Piedmont Geology

SP20 Delaware Piedmont Geology

The Red Clay Creek Valley traverses geologic features that have long been recognized as important to science, industry, and history. The reader will note that within the text “Piedmont,” and “Atlantic Coastal Plain” are capitalized. This is because these are formal geologic provinces. The “Fall Line” or “fall zone” is also an important geologic area. The Fall Line is the contact where the hard crystalline rocks of the Piedmont dip under and disappear beneath the sediments of the Coastal Plain. The fall zone is a narrow zone that parallels the Fall Line where rapids and waterfalls are common. The landscape and rock types shown in northern Delaware are classical examples of the larger geologic features that dominate the geology of eastern North America.