Abstract This paper examines lead and its many uses. It gives an historical overview of leaded products, such as leaded gasoline and leaded paint and how they were used. It details Detroit specifically and how it has already begun fighting its lead problem. It concludes that the elimination of lead poisoning everywhere, and in Detroit specifically, will result in more educated people, less crime and therefore a better city of Detroit.
From the Paper "One of the most pressing problems in American cities is the danger of lead levels in its suburbs. Excess exposure and contact with lead can result in lead poisoning. Throughout the 1900s, Detroit, in particular, used enormous amounts of leaded gasoline in automobiles and lead-based paint in Detroit housing. Unfortunately for Detroit citizens, lead is a poisonous substance that does not break down over time. Lead poisoning results in an array of physical and psychological defects, but poisoning can be prevented if the lead hazard is detected and if appropriate measures are taken to remove or contain the hazard. Detroit must take action to eliminate its lead poisoning problem."
Abstract This paper gives a detailed first person account of the earthquake in Santa Clarita, California from the eyes of a public information officer. It describes the policies such as: activating the Emergency Alert System, restoring power and more. It details the responses that were received by disaster relief personnel and how several organizations of emergency workers were able to deal with this crisis.
From the Paper "On Thursday the 15th of last month, at 7:31 a.m., an earthquake of 5.9 Moment Magnitude struck Southern California. The epicenter was near Santa Clarita, a small suburban community about twenty miles north of Los Angeles along the I-5 freeway. I am the Public Information Officer for the Emergency Response Office for the City of Santa Clarita. The following is an account of the five days following that earthquake."
The following paper discusses the climate of the U.S.A. and Canada, with respect to the climate classifications, its effects on farming and other activities.
Abstract This essay discusses how climate governs the entire ecological structure of the planet earth. The author examines how climate, in relation to the topography and latitudinal location, determines the vegetative types, the hydrology, soil, agriculture, and various human activities.
From the Paper "Climate represents a long term average of various weather features such as temperature and precipitation. The World Meteorological Organization uses 30-year averages to define climatological "normals" for these various features. Climate determines how resources such as water and vegetation are distributed and, until the onset of technology, climate also determined where people lived and worked. Many factors, such as topography, proximity to large bodies of water, and latitude affect a particular location's long-term climate. It is important to note that because a region's climatology is a 30-year average, significant year to year variability is likely. For example, a particular location may have a dry, warm winter one year and a record snowfall the next year"
Abstract A paper which explains the beginning of radioactive dating - a process which can give scientists the age of rocks and other materials and help us to identify when Earth began. The paper explores the progression of this method and its uses today, as well as discusses different methods that are used, other than carbon-12, such as potassium or argon dating.
From the Paper "Many view radioactivity as the end of the world in the event of a nuclear war. With its astonishing power, radioactivity could perhaps destroy and thus end the world. What many don't know about radioactivity is that is has the potential to tell scientists the age - or the beginning - of the Earth. Quite ironically, radioactivity could very well be responsible for both showing the beginning and the ending of Earth. A process called radiometric dating can give scientists the age of rocks and other materials and help us to identify when Earth began."
Abstract There are many techniques for dating within the field of archaeology, one of these methods is the The K-Ar (Potassium-Argon) method which has been a vast success within the field of geology. This paper examines how it works and what methods are used to glean the date from archaeological artifacts and remains.
From the Paper "It is possible to date rocks with a low potassium content such as basalts in this way. Sadly the dates are not always secure due to the behaviour of the geochemicals of the parent and daughter elements as they are likely to being disturbed by geological events such as weathering or reheating that normally take place during the formation of a rock. Potassium argon dating allows scientists to date volcanic rocks between two billion and 100,000 years old."
Abstract The following paper discusses acoustics signals that detect the presence and location of commercially useful fish, map the ocean floor to establish the safest paths for supertankers, explore the earth's geological formations and discover oil deposits in the ocean floor.
From the Paper "At a bottom of the permanent thermocline or below it, water temperature is uniform. Here, the pressure of the water column due to the depth takes over. The sound speeds then increase on account of increase in pressure. (Pacific) The deep sound channel axis is between 600 and 1,200 m below the sea surface at low and middle latitudes. This is deepest in the subtropics and come to the surface in high latitudes, where sound propagates in the surface layer. (Pacific)
Sound waves can be "trapped" in the deep sound channel and propagate in long distances. This is because these waves go through little attenuation beyond that, and this is due to geometric scattering or spread as well as minor volume scattering in water."
Abstract The main focus of this paper is the establishment of the thesis that the first known inhabitants of America were the PaleoIndians of the Ice Age time period. This thesis is supported by studies and secondary sources that support this claim. In addition to the geological evidence found, the lifestyle, culture and tools of the PaleoIndians is discussed.
From the Paper "The Clovis point is a piece of tool that was first found in Siberia. Several pieces of the same kind of tool was found in the U.S. states of New Mexico, Montana, and Colorado (Rose 1997). The tool was discovered after geologists studied the layering of soil, part of a study that might help lead to the discovery of an important artifact or preserved fossil resulting in evidence of the first inhabitants of America. The Clovis point was a crudely shaped hunting tool made of stone, often referred to as a ?spearpoint.? This tool became the key to the discovery of various information about the culture of the PaleoIndians."
Reviews typical earthquake characteristics. Describes the on in Kobe in 1/17/95. Assesses environmental impact of quake. Analyzes mitigation & repair efforts.
2,700 words (approx. 10.8 pages), 9 sources, 1996, $ 95.95
From the Paper "A simple definition of an earthquake would be the shaking of the Earth caused by a sudden movement of rock beneath its surface (USGS, 1996a). A more definitive explanation of earthquakes would focus on the passage of seismic waves which in turn create the violent shaking or vibrating motion of the ground. These motions are termed tremors. Seismic waves are caused by the release of energy from a sudden movement along a fault. A fault is a fracture in the Earth's crust where there has been a displacement of rock (Marsh, 1987, 292).
The movement of air and water is easy to accept because we experience these things everyday. In truth, the physics behind..."
From the Paper "Each year, portions of the United States are battered by the high winds and rains of hurricanes. These storms can cause massive damage depending on the speed of the winds and the precise areas of land where the storms come ashore. These storms are carefully tacked by various scientific and governmental entities which measure the speed of the wind, the direction of the storm, and the course of the devastation wrought by them. During the hurricane season, there are likely to be a succession of such storms which fortunately do not usually assault the same locales and which may also miss the land altogether or dissipate before reaching land. An analysis of three recent storms will show the sort of devastation they can bring.
Probably the major storm of 1992 was Hurricane Andrew, which left behind considerable devastation in Florida and other regions so ..."
From the Paper "In Time's Arrow, Time's Cycle, Stephen Jay Gould discusses the evolution of geologists' understanding of the concept of deep time. Gould studied texts by Thomas Burnet, James Hutton, and Charles Lyell--three scientific writers who approached this question in the seventeenth, eighteenth, and nineteenth centuries. Traditionally, readings of these three writers tended to focus on the degree to which each man employed the scientific method in investigating the question of the Earth's age. The greater the scientist's dependence on scientific method, the historians reasoned, the closer he came to the truth. Thus, these scientists have often been ranked, and understood, on the basis of their adherence to standards that are familiar to the twentieth century, but were still evolving when they wrote. In the course of his repeated close readings of the texts, in which.."
Examines role of sandstone in identification of geological properties in western Miditerranean, Massachusetts/Connecticut, eastern Australia, and California/Oregon.
2,025 words (approx. 8.1 pages), 6 sources, 1997, $ 71.95
From the Paper "INTRODUCTION
Different landscapes are associated with the underlying bedrock on which they are found, and the relationship involves various evolutionary and developmental processes by which certain underlying strata influence the evolution of the landscape above. Research on this issue has postulated a number of processes to explain the landscape that has been associated with sandstone bedrock. This research has examined different regions of the world and traced the evolution of the region through different geologic eras. The nature of the sedimentary deposition has been examined in several parts of the world, along with the tectonic forces that helped shape the terrain. The nature of the landscape seems to depend in part on the specific locale with relationship to the interaction of continental plates, which.."
From the Paper "Ophiolite
Introduction
This research examines ophiolite, an igneous rock formation [1]. Descriptive information on ophiolite is included in this examination, and both the formation of ophiolite and the significance of ophiolite to the study of geology are addressed in this examination.
Definition and Description
Ophiolite is igneous rock material that has formed into slabs from the lithosphere that have been deposited at continental margins [2]. Ophiolite formations are known to have volumes as large as 50,000km2 [3]. Ophiolite formations, however, are thin-depths less than 20km. Ophiolite formations also are dense-3,000-to-3,300kg m-3 [3].
Character of..."
From the Paper "The Sea Floor
The birth and death of oceans is a continuous process. As an example, one ocean may be growing by sea-floor spreading from a mid-ocean ridge while another ocean is closing because of the continents forcing the ocean floor down at the trenches. Some oceans, thus, are young and growing, while other oceans have reached maturity, and still others may be disappearing with the joining of the continental masses [1:1-7].
The theory of plate tectonics envisages the crust of the earth together with the upper part of the mantle, which form the lithosphere, as consisting of rigid slabs, or plates, that are continuously moving their position in relation to one another. Below the lithosphere is the asthenosphere, which is thought to be plastic [2:1-11].
The plates are..."
Abstract This paper is divided into two parts. The first part distinguishes between glacial erosion and weathering and the second part discusses the varying influence of the factors affecting the rate and type of glacial erosion. The paper shows that the main type of glacial erosion is abrasion and the characteristics of both the bedrock and the abrasive rock have a large influence on abrasion rates.
From the Paper "The concept of glacial erosion can be considered using the "systems approach", with the factors that influence the erosion as the inputs, the type and rate of the erosion itself as the processes, and the resultant landforms and characteristics as the outputs. The type of erosion that has the largest effect on the landscape is abrasion. Abrasion is the process by which entrained, subglacial debris grinds against the bedrock as the glacier moves, and wears the bedrock away as a result. There are three factors that are essential for abrasion to occur."
Tags: geography, glacier, meltwater, Pressure, Melting, Point
Abstract The paper shows that according to recent research, the earth's magnetic field has shown signs that it is ready to shift. If this occurs, the magnetic north will point south and the magnetic south will point north and have disasterous effects on Earth. The paper discusses how scientists measure the magnetic field by tracking its history from a gigantic crack in the middle of the Atlantic Ocean that oozes lava. As the lava solidifies into rock, it records the Earth's magnetic polarity at various times. According to these records, the Earth is overdue for another reversal. The paper shows that prior to a magnetic field reversal, the magnetic field typically grows weaker and weaker until it almost disappears. As a result, the poles flip and strong magnetism starts up again. The paper explains how magnetism levels in ancient pottery indicate that over the past 4,000 years, the magnetic field has weakened by about half. In this century alone, it has decreased by five percent. The paper explores theories put forth by scientists that the Earth's magnetic field could disappear in the next few hundred or thousand years.
Table of Contents
Abstract
Introduction
Origin of the Earth's Magnetic Field
Paleomagnetism
Field Reversals
Theories of Magnetic Pole Reversals
Earth's Magnetic Field
The Main Field
Secondary Field
Remanent Magnetization
Electromagnetic Dynamo Effect
Magnetization of Rocks
Curie Point
Processes of Magnetization in Rocks
Magnetic Anomalies
Paleomagnetic Data
Morphology of Reversals
Field Direction and Field Intensity
Field Reversals
What Drives Reversals?
Core-Mantle Boundary Processes
Bibliography
From the Paper "Over the past three-and-a-half million years, the Earth's magnetic poles have shifted approximately nine times. This estimate has been found through sampling of the magnetic records formed by rocks in the ocean beds and in ancient lava formations.
Scientists do not know how or why the magnetic poles reverse for sure, nor do they know exactly what effect this will have on life, as we know it. Many believe that the magnetic poles of the Earth reverse an average of every 200,000 years, but the time between reversals has varied widely. The Sun reverses its magnetic poles fairly routinely: essentially every 11 years."
