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Site content related to keyword: "Delaware"

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.

OFR1 A Preliminary Report on Nitrate Contamination of Shallow Ground Waters in Delaware

OFR1 A Preliminary Report on Nitrate Contamination of Shallow Ground Waters in Delaware

Inspection of water analyses on file at the Delaware Geological Survey revealed that 25 percent of the shallow wells yield water with nitrate concentrations approaching or in excess of the Delaware State Board of Health and U. S. Public Health Service limit of 45 parts per million (ppm). Nitrate concentrations greater than 45 ppm seem to be detrimental to the health of infants during their first few months of life; adults drinking the same water are not affected but breast-fed infants of mothers drinking such water may become ill. The illness ("blue baby sickness" or methemoglobinemia) results from the conversion of nitrate to nitrite by nitrite-forming bacteria in the upper part of the digestive tract of some infants and the further conversion of hemoglobin to methemoglobin which is incapable of transporting oxygen; the result is oxygen starvation. Little is known about the low level effect of undetected methemoglobinemia on infants.

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RI39 Earthquakes in Delaware and Nearby Areas, June 1973 - June 1984

RI39 Earthquakes in Delaware and Nearby Areas, June 1973 - June 1984

Earthquakes in Delaware and surrounding areas have been well documented historically since about the early 1700’s and since 1972 by instrumental records. Most of the Delaware events have occurred in the Wilmington area immediately adjacent to or within rocks of the Wilmington Complex. Since the compilation of earthquakes by Jordan and others (1974) which lists events through May 1974, six felt earthquakes have occurred in northern Delaware and about 20 additional events in Delaware have been recorded on seismographs of the Delaware Geological Survey. Four of the felt events took place from November 1983 through February 1984 and ranged from a magnitude 1.5 to 2.9. The highest intensity for this series of earthquakes was a possible V (Modified Mercalli). Epicenters were generally in the north Wilmington area as determined both instrumentally and by felt reports.

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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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OFR30 Evaluation of Remote Sensing and Surface Geophysical Methods for Locating Underground Storage Tanks

OFR30 Evaluation of Remote Sensing and Surface Geophysical Methods for Locating Underground Storage Tanks

Delaware Code, Title 7, Chapter 74, Section 7415 states in part: "The Delaware Geological Survey shall investigate the feasibility of utilizing aerial photographs and other new advanced techniques for locating abandoned tanks." In response to this charge, the Delaware Geological Survey has completed a survey of currently available remote sensing and geophysical tools to determine which methods may be utilized to locate underground storage tanks. Limited preliminary field testing has been performed.

OFR28 Potential for Ground-Water Recharge in the Coastal Plain of Northern New Castle County, Delaware

OFR28 Potential for Ground-Water Recharge in the Coastal Plain of Northern New Castle County, Delaware

This map was constructed primarily to indicate the possibilities for artificial recharge into both the surficial sediments of Quaternary age (exclusive of soils) and the older, immediately underlying sediments. However it can also be used to determine where natural recharge might be entering the ground most readily in those areas relatively free from impermeable cover. The surficial sediments include micaceous sands and gravels in the vicinity of the Fall Line derived from underlying crystalline rocks, Holocene marsh deposits, Delaware River sediments, and the Columbia Formation of Pleistocene age. The Columbia Formation is composed of poorly sorted sands with some gravels, silts and occasional clays. The unit is one of the most important ground-water reservoirs in New Castle County.

B5 Sedimentary Petrology of the Cretaceous Sediments of Northern Delaware in Relation to Paleogeographic Problems

B5 Sedimentary Petrology of the Cretaceous Sediments of Northern Delaware in Relation to Paleogeographic Problems

The non-marine Cretaceous sediments of northern Delaware older than the Magothy formation cannot be divided accurately into formations or mappable geologic units because their lithologic characteristics are very similar. However, two heavy mineral zones can be distinguished in these deposits: a lower staurolite-kyanite-tourmaline-zircon zone, and an upper tourmaline-zircon-rutile zone with abundant alterites. They have been named the Patuxent zone and the Patapsco-Raritan zone respectively. The Magothy formation is characterized by abundant staurolite and also contains significant amounts of tourmaline. The marine Upper Cretaceous deposits have a greater variety of heavy minerals than the underlying non-marine sediments. They contain abundant epidote; chloritoid, first appearing at the base of the Merchantville formation, is persistently present. Garnet is found in the Merchantville and the Mount Laurel-Navesink formations. The heavy mineral composition of the Cretaceous sediments is shown in table IV.

RI30 Ground-Water Levels in Delaware July, 1966 - December, 1977

RI30 Ground-Water Levels in Delaware July, 1966 - December, 1977

Water-level records from 13 observation wells in Delaware for the period July, 1966 - December, 1977 provide the bases for the analyses of water-level fluctuations. Water levels in shallow water-table wells generally rise from November to March, when recharge exceeds discharge, and decline during the warm growing season from May through September. Although water-levels in individual wells changed by as much as 11.17 feet during the 11.5 year period studied, the water-table system remained in a state of dynamic equilibrium and exhibited no permanent changes in aquifer storage. However, the water levels in three artesian observation wells have declined during the same 11.5 year period in response to high demands for ground water while levels in the other two artesian wells have risen slightly due to a reduction in ground-water discharge, or increase in ground-water recharge, or both. Nevertheless during the past several decades, water levels have declined, cones of depression have enlarged, and reductions in aquifer storage, have occurred in the Potomac aquifer in central and southeastern New Castle County, and the Piney Point and Cheswold aquifers in the Dover-Dover Air Force Base area. Therefore, future groundwater development in the artesian aquifers must be carefully planned and managed.

SP23 Earthquake Basics

SP23 Earthquake Basics

This report provides a brief overview of the causes of earthquakes, how earthquakes are measured, and a glossary of earthquake terminology.

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SP17 The Delaware Geological Survey: The Formative Years, 1951-1969

SP17 The Delaware Geological Survey: The Formative Years, 1951-1969

Emphasis is placed herein on the years of Dr. Groot's leadership of the Survey. The remarkable work of James C. Booth in the last century is acknowledged but has elsewhere been entered in history. Some continuing activities of the Survey after 1969 are noted together with comments of an experienced observer; this current period may someday receive the attention of a recorder having the enhanced perspective of time.

SP8 Memoir of the Geological Survey of the State of Delaware

SP8 Memoir of the Geological Survey of the State of Delaware

The following report of the geological survey of the state of Delaware, conducted in the years 1837 and 1838, embraces all the observations and examinations which were made during the continuance of the survey, including those contained in the first and second annual reports, already laid before the legislature.

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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Introduction to the Hydrogeology of Delaware

Brandywine Creek

Delaware’s water, both ground and surface, is one of its most important natural resources. As Delaware’s lead earth science agency, the Delaware Geological Survey provides information to inform and educate resource managers and the public to better understand and manage our water resources.

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.

Delaware State Fossil - The Belemnite

Delaware State Fossil (Belemnitella <i>americana</i>)

On July 2, 1996, Belemnitella americana was named as the official fossil of Delaware. The Martin Luther King, Jr. Elementary School (Wilmington) third grade Quest students of Kathy Tidball suggested honoring the ancient and noble belemnite as our State fossil.(Delaware Code Title 29 § 314)

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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.

The Delaware DataMIL

The Delaware DataMIL

The Delaware DataMIL collects, maps, and serves Delaware's Spatial Data Framework, or basic map datasets, on which state agencies, local and county governments, academic GIS users, and the private sector can use for their own needs. DataMIL also provides access for Delaware topographic maps that replace the old USGS 7.5-minute topographic maps for the State.

Rapid infiltration basin systems -- research introduction

A. Scott Andres, senior scientist with the Delaware Geological Survey, presented "Rapid Infiltration Basin Systems -- Research Introduction" to the Delaware Clean Water Advisory Council on June 24 in Dover, Del.

DGS Staff Directory

DGS staff directory lists all full-time science and administrative personnel. It includes interactive areas of interest and a comprehensive listing of each staff members' projects, publications, and activities.