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Site content related to keyword: "minerals"

Delaware Geological Survey welcomes new director Wunsch

David R. Wunsch, Ph.D., P.G.

David R. Wunsch is the new Director and State Geologist at the Delaware Geological Survey.

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.

RI56 The Setters Formation in the Pleasant Hill Valley, Delaware: Metamorphism and Structure

RI56 The Setters Formation in the Pleasant Hill Valley, Delaware: Metamorphism and Structure

The Setters Formation, identified on the southeast side of Pleasant Hill valley in well Cb13-16, contains the prograde mineral assemblages (1) microcline, biotite, and sillimanite +/- garnet, and (2) microcline, biotite, sillimanite, and muscovite +/- garnet. These pelitic assemblages allow us to infer peak metamorphic conditions between 620° and 680°C and 4 to 6 kilobars pressure, if PH20/Pfluid is > 0.5. There is some evidence in the drill cuttings to indicate that partial melting accompanied the formation of sillimanite, thus constraining peak temperature to > 640°C.

SP10 Selected Papers on the Geology of Delaware

SP10 Selected Papers on the Geology of Delaware

The Delaware Academy of Science has been instrumental in informing Delaware citizens about science and utilization of local resources. Since 1970 the annual meeting of the Delaware Academy of Science has been used as a time for presentation of ongoing research in various areas of science in the Delaware region. The proceedings of these meetings have resulted in publication of transactions of the Delaware Academy of Science. The 1976 annual meeting focused on aspects of the geology of Delaware. Members of the Delaware Geological Survey and the Geology Department at the University of Delaware contributed papers in their specific disciplines. This volume presents an overview of studies of geological features and processes of evolution of the geology of Delaware. Although this collection of papers does not represent an all-inclusive study of the subject, the selections included in this volume highlight past, present, and future trends in the study of Delaware's geology. It is hoped that the combined bibliographies of all the papers will provide a comprehensive view of the literature for further investigation into the geology of Delaware.

Glauconite (Greensand)

Glauconite (Greensand)

Greensand is composed primarily of the mineral glauconite -- a potassium, iron, aluminum silicate. In some Delaware greensands, the glauconite content exceeds 90%. The remaining 10% is mainly quartz. In the past, greensand was used in Delaware as an inexpensive fertilizer. The only active greensand mine in the U.S. today is in New Jersey. Once mined, greensand is dried and used as a soil conditioner. Greensand is also used in water softeners primarily to remove iron from the water. Recent research has shown that greensand has the potential for use as a filter of heavy metals from industrial waste water and landfill leachates.

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Sand and Gravel

Locations of Sand and Gravel Producers in Delaware

Sand and gravel are essential for supporting and maintaining economic development throughout Delaware. These natural resources are used primarily for aggregate in the productions of concrete for residential, commercial, and industrial buildings, bridge and highway construction, fill for road beds and foundations, water and wastewater treatment facilities, and for replenishment of our Atlantic and Delaware Bay beaches.

Woodlawn Quarry: A GeoAdventure in the Delaware Piedmont

Woodlawn Quarry: A GeoAdventure in the Delaware Piedmont

A visit to Woodlawn Quarry is suitable for ages 10 to adults and provides an interesting opportunity to observe common mineral specimens, identify the quarry as an early mining site, appreciate the physical work necessary to quarry rock with hand tools, and discuss the economic importance of the minerals found in the quarry. The minerals that can be readily found and identified in the quarry are feldspar, quartz and mica.

OFR5 Removal of Metallic Contaminants from Industrial Waste Waters by the Use of Greensands, A Preliminary Report

OFR5 Removal of Metallic Contaminants from Industrial Waste Waters by the Use of Greensands, A Preliminary Report

The Delaware Geological Survey, in cooperation with the U. S. Bureau of Mines, has investigated glauconite-bearing greensand deposits in Delaware for several years. The purpose of this effort is to find possible practical uses for this potentially important mineral resource. This report briefly describes the preliminary results of one phase of the study: application of greensands to the purification of industrial waste waters.

RI40 Sodium Concentrations in Water from the Piney Point Formation, Dover Area, Delaware

RI40 Sodium Concentrations in Water from the Piney Point Formation, Dover Area, Delaware

In the greater Dover area sodium concentrations in ground water from the glauconitic Piney Point Formation commonly exceed 100 parts per million. Investigation of chemical characteristics of the water, and statistical analyses of the results, show that these high concentrations are due to a natural ion-exchange process. Calcium in water replaces sodium in the mineral glauconite and causes the sodium enrichment in ground water.

RI32 Removal of Metals from Laboratory Solutions and Landfill Leachate by Greensand Filters

RI32 Removal of Metals from Laboratory Solutions and Landfill Leachate by Greensand Filters

Distilled water spiked with heavy metal cations was passed at a rate of 2-4 ml/min through a filter composed of greensand containing about 80 percent glauconite. The capability of the greensand to trap metal cations is increased by prolonging the contact time between the leachate and the greensand. Flushing the charged greensand filter with water does not cause significant release of cations back into solution, suggesting that polluted greensand might be disposed in landfills without adding pollutants to either ground or surface water in the vicinity.

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B13 Geology, Hydrology, and Geophysics of Columbia Sediments in the Middletown-Odessa Area, Delaware

B13 Geology, Hydrology, and Geophysics of Columbia Sediments in the Middletown-Odessa Area, Delaware

Columbia sediments in the Middletown-Odessa area are composed of boulders, gravels, sands, silts and clays. These sediments are exposed in four gravel pits where their structures and textures were studied. Subsurface geology was interpreted on the basis of the well-log data from 40 holes drilled in the area of study. Columbia sediments were laid upon a surface made up of the greensands of the Rancocas Formation (Paleocene – Eocene age). The contact between the Rancocas and Columbia Formations is an erosional unconformity.

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.

SP19 Delaware: Its Rocks, Minerals, and Fossils

SP19 Delaware: Its Rocks, Minerals, and Fossils

Minerals are naturally occurring, inorganic substances with characteristic physical and chemical properties. Common examples found in Delaware are quartz (hard, glassy luster), mica (cellophane like pieces), and feldspar (waxy or pearly luster, cleavage). In nature minerals are usually found in mixtures with other minerals. A natural specimen containing several minerals is called "a rock." A common example is granite, which is a mixture of quartz, feldspar, mica, and usually other dark minerals. Fossils are any evidence, direct or indirect, of a pre-existing plant or animal in the rock record. The most popular area for collecting fossils in Delaware is the Chesapeake and Delaware Canal area.

Minerals in Delaware

Minerals in Delaware

The description and identification of minerals in Delaware dates from the first quarter of the nineteenth century. During this time, both geologists and amateur mineral collectors have published on the minerals of Delaware including George Carpenter, Issac Lea, James Booth, and Henry duPont.

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Delaware State Mineral - Sillimanite

Sillimanite - Delaware State Mineral

In 1977, the Delaware General Assembly, acting on a proposal by the Delaware Mineralogical Society, established sillimanite as the Delaware State Mineral. This act recognizes the geological and mineralogical significance of the large masses of this mineral found as boulders at Brandywine Springs, an occurrence that was recognized as important in the 6th (1892) edition of Dana's System of Mineralogy. The Brandywine Springs boulders are remarkable for their size and purity. The sillimanite has a fibrous texture reminiscent of wood and could potentially be cut into cabochon gems showing a chatoyant ("cat's eye") effect. Sillimanite is not mined as an ore or raw material in Delaware.