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The Ozone Layer, 2002.
A discussion of the different causes and their detrimental effects on the ozone layer.
1,884 words (approx. 7.5 pages), 7 sources, MLA, $ 60.95
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Abstract
This paper examines data on the effects of aircraft emissions on stratospheric ozone since the 1960s discovery that the emission of nitrous oxides and water vapor in the engine exhaust from supersonic transport planes may be destructive to the ozone layer. The ozone layer is the layer which keeps much of the sun's biologically harmful ultra-violet radiation from reaching the Earth's surface stratospheric ozone. It also analyzes how the continual destruction and production of ozone and the complex reactions between aerosols and exhaust emissions makes it difficult to assess the extent of the problem with currently available data.
From the Paper
"In 1971, Crutzen's theory was used to block the plan for the development of a fleet of high-speed supersonic aircraft (SSTs). It was believed that the nitrogen oxides in the exhaust from these planes would pose a serious threat to the ozone layer. As a result, the U. S. SST plan was abandoned. It is paradoxical that, while the environmental consequences of increasing the number of high-speed aircraft are viewed as being a serious threat to the ozone layer, air travel continues to increase annually (7). The demand for faster aircraft for travel to more distant destinations is spurring atmospheric chemists to research the effects of emissions from SSTs, and to develop ways to make engines whose exhaust is less damaging to the ozone layer."
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Earthquakes and Hurricanes, 2002.
A discussion of recent phenomena of earthquakes and hurricanes and their effects.
1,573 words (approx. 6.3 pages), 6 sources, MLA, $ 51.95
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Abstract
This paper examines the damage recently caused by the natural phenomena of earthquakes and hurricanes and measures that can be taken to to predict their arrival in order to prepare for them. In particular it looks at Hurricane Dennis, which menaced the coast of North Carolina and Hurricane Floyd, which led to a huge evacuation of people from Florida, Georgia and South Carolina. It also discusses the devastating effects of the two earthquakes that hit Turkey in 1999.
From the Paper
"The other major natural disaster in the fall of 1999 has been earthquakes, of which there have been several considered major in impact. Indeed, Turkey has been hit twice in different regions of the country. The earthquake in August left a death toll originally estimated to be about 500. This was a quake of magnitude 7.8 on the old Richter scale, making it almost as powerful as the 7.9 in San Francisco in 1906, which killed 700 people. The earthquake in Turkey struck at 3 am. Dozens of buildings collapsed. It is often noted in American cities when there is an earthquake at that hour that the death toll would have been much higher in the daytime when people were out on the street, but it is not clear that this would be true in areas like Turkey where buildings are not as well-constructed and where most of those killed were sleeping in their own beds when the house collapsed about them."
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A Look at the Big Bang Theory, 2002.
A study of the sources that support and question the Big Bang Theory of the beginning of the universe.
1,439 words (approx. 5.8 pages), 4 sources, MLA, $ 47.95
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Abstract
The writer gives a background of the Big Bang Theory and explores the theory as an explanation of the beginning of the universe. However, since the 1940s and the introduction of this theory, scientists have raised questions as to the validity of the explanation and continue to research other ways in which the universe might have been created. The paper traces some of this research.
From the Paper
"One such area of research has been the model for the expansion of the universe and so for the Big Bang. One theory offered to explain this is the inflationary model, and over the last two decades what has happened to this model shows some of the ways scientific truth is pursued and fine-tuned. Alan Guth developed the idea in 1979 and wrote it in his notebook. Inflation was the name for the mechanism Guth proposed for igniting cosmic expansion and which might have operated for as little as 10-35 seconds. Still, it would have whipped up all the matter and energy in the universe and laid the seeds for galaxies and galaxy clusters in that brief time, and in that time the universe would have blossomed exponentially from as small as 10-24 centimeters across to perhaps the size of a pumpkin. Michael Turner of the University of Chicago describes inflation as "the most important idea in cosmology since that of the big bang itself.""
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Loma Prieta Earthquake, 2002.
An analysis of the October 1989 Northern California earthquake.
900 words (approx. 3.6 pages), 2 sources, $ 31.95
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Abstract
Analysis of the October 1989 Northern California earthquake. Creation of the 7.1 magnifude quake by a slip in the San Andreas fault line. Depth of the quake. Occurrence of aftershocks and their magnitude. Areas of devastation; why some areas suffered greater damage than others. Landslides. Probability of a repeat high magnitude earthquake.
From the Paper
"1989 Loma Prieta Earthquake
The 1989 Loma Prieta Earthquake occurred at 5:04 PM on Tuesday, October 17, 1989. It was measured as a magnitude 7.1 on the Richter scale, a device utilized for measuring earthquake strength. It lasted about 20 seconds and was centered approximately 60 miles south of San Francisco. The tremor could be felt as far south as San Diego and as far east as Western Nevada. This earthquake was pinpointed along the San Andreas Fault line, long considered one of the most dangerous and active portions of the fault.
The famed San Andreas fault line runs along a northwesterly direction about 800 miles from the Gulf of California up to Cape Mendocino just north of San Francisco. This particular fault has been the source of many large quakes, including the 7.0 1838 quake on the..."
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Northridge Earthquake, 2002.
An analysis of the January 1994 Southern California earthquake.
900 words (approx. 3.6 pages), 1 source, $ 31.95
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Abstract
Analysis of January 1994 Southern California earthquake. Focal depth of 6.7 magnitude quake. Blind thrust type quake. The fault involved (Oak Ridge system, Pico thrust). Types of damage from the quake (liquefacation, lateral spreading, landslides, differential compaction). Greter damage to Santa Monica. Comparison to 1971 Sylmar earthquake. Retrofitting & engineering codes.
From the Paper
"1994 Northridge Earthquake
The 1994 Northridge Earthquake occurred at 4:30:55 AM PST on January 17, 1994. It was measured as a magnitude 6.7 on the Richter scale. This quake occurred along the Northridge Thrust, a fault that is also known as the Pico Thrust. It was centered about 20 miles northwest of Los Angeles and approximately 1 mile south?southwest of Northridge. This quake was a blind thrust type quake.
This particular fault dips to the south at an almost 45 degree angle. As a result, quakes along this fault and similar thrust faults falsely appear far removed from the surface trace. This particular fault forms the ridge slightly to the south of its trace, paralleled by the Santa Clara River and California Sate Highway 126. It begins near the town of Piru in the east and ends just..."
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Hermit Crabs, 2002.
Discusses different kinds of Hermit Crabs, their habitats and their characteristics.
1,125 words (approx. 4.5 pages), 4 sources, $ 39.95
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Abstract
Discusses different kinds of Hermit Crabs, their habitats and their characteristics. Usefullness in research. Series of activities of Hermit Crabs value for research into decision-making. Importance of shells and skill selection behavior. Ability of researchers to observe the assessment procedure of the crabs. Variouis experiments on Hermit Crabs in reference to animal behavior; response to stimuli.
From the Paper
"Hermit crabs usually are found in empty gastropod shells, seeking protection from predators, desiccation, and other hermit crabs. The hermit crab does not seem to select a place to stay at random but rather appears to have a selection process. Precisely what this process is and how the crab makes a decision as to what shell to select and what shell to reject is the subject of much research.
Hermit crabs are crustaceans that live in the wild in the western Atlantic. They mate on land near the sea, and once the eggs develop, the female carries the eggs on her abdomen to the sea and leaves them on wet sand or a wet rock for the tide to carry out to sea. There are usually 1,000 to 50,000 eggs at a time. At sea, the crabs are small larvae that molt several times in order to grow to adulthood. At the adult larvae stage..."
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Mount St. Helen?s, 2002.
A discussion of the volcanic Mount St. Helen's, its history, eruption process and aftermath.
1,621 words (approx. 6.5 pages), 9 sources, MLA, $ 52.95
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Abstract
This paper begins by providing a brief geological history of the mountain, seperating it into nine different periods. It then examines various lava types found in the area. The paper moves to modern day when the first actual threat was realized for eruption. It discusses the process of eruption and the different types of blast - lateral blast (direct blast zone, channelized blast zone, seared zone); vertical blast and pyroclastic flows. It concludes with an analysis of the aftermath and its effect on wildlife in the area.
From the Paper
"On May 18, 1980, Mount St. Helen?s in southwestern Washington erupted with a massive explosion. Leading up to this day was increasingly intense earthquake activity. There were also lots of relatively weak eruptions and many locations of minuet gas discharge. The devastating impact of the suddenly unleashed volcanic energy caused the worst volcanic and geological disaster in the recorded history of the United States."
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Radioactive Dating, 2002.
An introduction to the history and methods of the various types of radio carbon dating.
1,842 words (approx. 7.4 pages), 9 sources, MLA, $ 59.95
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Abstract
Radioactive dating is the process of determining the age of rocks and other specimens from the decay of their radioactive elements. By applying this information, geologists are able to decipher the 4.6-billion-year history of the earth. The paper introduces the history of this type of dating in chronological order. It discusses other issues related to radioactive dating such as Carbon-14 dating, fission track dating, Potassium Argon Dating, the Rubidium-Strontium method, lead-alpha age and debated ideas of radioactive dating.
From the Paper
"Cosmic rays from the sun strike nitrogen 14 atoms in the earth?s atmosphere and cause nitrogen atoms to lose a proton making it a carbon isotope this then turns into radioactive carbon 14, which combines with oxygen to form radioactive carbon dioxide. All living things are in equilibrium with the atmosphere, and the radioactive carbon dioxide is absorbed from the air and used by green plants. Then the radioactive carbon dioxide gets passed on through the plants into the food chain and the carbon cycle. All living things contain a constant ratio of Carbon 14 to Carbon 12 of about 1 in a trillion. The amount of carbon 14 lost in a species is continually replenished as long as it still takes in food and oxygen. At death, the exchange of carbon 14 ceases and any that is left in the tissues of the organism begins to decay to Nitrogen 14, this is not replenished by any new C-14. The change in the Carbon 14 to Carbon 12 ratio is the basis for dating this dating technique. The half-life is so short (5730 years) that this method can only be used on materials less than 70,000 years old. A lot of archaeological dating uses this method. It is also very useful in attempting to date remnants of the ice ages (Pleistocene epoch.)"
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Ozone Layer Depletion, 1995.
Examines causes and environmental effects, history, CFMs, statistics, ultraviolet radiation, U.S. and global corrective measures and the future.
1,350 words (approx. 5.4 pages), 10 sources, $ 47.95
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From the Paper
"OZONE LAYER DEPLETION AND ITS EFFECTS
Introduction
The ozone (O3) layer of the Earth's upper atmosphere exists from 50,000 to 120,000 feet (10:2127). Ozone at this level of the earth's atmosphere is generated by the absorption of ultraviolet radiation by oxygen (O2). In forming ozone, ultraviolet radiation of wavelengths between 290 and 320 manometers is absorbed and thus not allowed to reach the surface of the Earth. Concentrations of ozone are a few parts per million, variously estimated between 5 and 10 ppm (10:2127). Unstable ozone molecules are also constantly being created and destroyed by complex natural forces involving solar radiation and interactions with very minute quantities of other gases. Ozone concentrations fluctuate naturally on a daily, seasonal, and ..."
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Natural Disasters, 1995.
Discusses these in general and gives examples (the 1993 Midwest floods and the 1994 Southern California earthquake). Examines the impact on community infrastructure, basic services and insurance companies.
2,025 words (approx. 8.1 pages), 9 sources, $ 71.95
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From the Paper
"Introduction
Natural disasters come in many forms: floods, fires, earthquakes, tornadoes, volcanic eruptions and landslides are but a few of the calamities that people endure. It is when nature comes into conflict with humans that catastrophe results. The response to these natural disasters has been to invest in early warning systems in order to protect lives and property, and to offer residents and businessmen advice on how best to survive the types of disasters that any one area is prone to. Fortunately, not all parts of the world are subject to every type of disaster, which means that people in any one area have to prepare only for those disasters which are likely to occur in their area. Such preparation can take the form of developing evacuation programs and finding ways to minimize damage both to people, livestock and ..."
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Northridge Earthquake, 1995.
Examines the geological causes and effects of the 1994 California quake and its impact on structures.
3,150 words (approx. 12.6 pages), 18 sources, $ 111.95
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From the Paper
"The Northridge Earthquake
For most Americans, January 17, 1994 was a holiday. The date marked the anniversary of Martin Luther King, Jr.'s birthday. Government offices were closed and observance ceremonies were attended. For the residents of Los Angeles, however, January 17 was be spent quite differently. On that particular Monday morning, the city awoke to natural disaster. The temblor struck at 4:31 a.m. local time. It had been roughly six decades since a major earthquake had occurred directly under an urban area in the United States. The event resulted in the loss of life, thousands of injuries, and enormous damage. Indeed, the Northridge earthquake eventually proved to be the costliest natural disaster in the nation's history.
California earthquakes are tectonic in nature. They result ..."
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Continental Drift, 1995.
This paper analyzes 18th -19th Century German scientist Alfred Wegener's ideas of continental drift, which led to the plate tectonic theory.
2,250 words (approx. 9.0 pages), 7 sources, $ 79.95
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From the Paper
"During the past century, considerable advances have been made in the field of geology. The discovery of plate tectonics has provided researchers with a unifying theory that explains many fundamental earth processes. Of the various hypotheses that led to plate tectonic theory, the most important was proposed by Alfred Wegener. Wegener's ideas on continental drift were supported by much evidence. However, perhaps because of its overwhelming implications, the theory was met with considerable resistance. Only in recent decades has scientific investigation collected sufficient evidence to definitively establish the validity of the continental drift hypothesis.
The theory of plate tectonics describes a lithosphere consisting of approximately the Earth's outer 100 kilometers.... "
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General Circulation Models, 1995.
This paper discusses the use and evaluation of General Circulation Models as climatic simulations in environmental science: Definition, significance, development, problems, approximations, form and function. Abstract.
3,825 words (approx. 15.3 pages), 18 sources, $ 135.95
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From the Paper
"General circulation models (GCM) are used to evaluate past, present, and future climatic phenomena. Climate consists of a region's prevailing weather. Variations in climate are primarily determined by the combined influences of the atmosphere, the continents, and the oceans. Such effects can both foster and hinder human activities. Consequently, considerable effort has been devoted to climate modeling.
In recent years, GCMs have been the primary tool used for climate simulation. These numerical representations describe climatic change in three-dimensions. The models involve numerous data inputs. In addition, they also require various ... "
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Erosion of the Long Island Shoreline, 1994.
This paper discusses the erosion of the Long Island shoreline: Geology, rate, causes and effects, role of humans, stabilization and management.
1,350 words (approx. 5.4 pages), 17 sources, $ 47.95
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From the Paper
"In the United States, extensive barrier.beach systems occur along major portions of the Atlantic and Gulf coasts. These fragile coast lines are in a continual state of flux. Beach erosion and accretion can result from both natural and man.made causes. Sea level change, storms, and development may all significantly impact these environments. On Long Island, New York, beach stabilization has repeatedly been attempted. Such efforts typically meet with varied success. In fact, many believe that the island's past stabilization projects have actually contributed to its current erosion problems. Geologically, Long Island consists of moraine sediments deposited by glacial drift. This mixture of crystalline gravel and boulders was scraped up in New England, carried several ... "
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California Earthquakes, 1994.
This paper discusses primarily California earthquakes: Major faults, research, geology, potential for disaster, safety measures and Midwest quake dangers.
1,575 words (approx. 6.3 pages), 4 sources, $ 55.95
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From the Paper
"For decades, Californians have lived with the knowledge that the San Andreas Fault could produce a magnitude eight earthquake. However, California's most recent earthquake, in early 1994, measuring 6.6 on the moment-magnitude scale--a measure of earthquake energy that has largely replaced the Richter scale--did not come from the San Andreas Fault. It was caused by a smaller fault in the San Fernando Valley that lay hidden deep underground, some nine miles down. While this was not considered the Big One, it still caused widespread damage: collapsed buildings and freeway bridges, fires, deaths and injuries, utility outages, and damage to property.
Soon after the first tremor, seismologists began trying to map out the newly revealed fault to determine how it is connected to other fissures in the region. To complete this task, the ... "
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Landslides in Southern California, 1994.
A look at the causes, examples, geologic process, types, materials, climate, vegetation, liability and remedies.
2,250 words (approx. 9.0 pages), 13 sources, $ 79.95
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From the Paper
"Mass Wasting in Southern California
More mass movement occurs in southern California than in any other region of the United States. Multiple factors contribute to this slope instability. Some of these include the area's steep hillsides, weak bedrock materials, adverse geologic structures, and heavy episodic precipitation. Recent landslides in Pacific Palisades, Palos Verdes, San Clemente, and Anaheim Hills have caused millions of dollars in damage. Moreover, as development continues to expand, southern California's landslide problem is only expected to worsen.
Mass earth movements are highly variable. Typically, they occur within the following spectrum: e.g., from movements which are dependent upon some fluid, to those which are not. In subaerial environments, this spectrum comprises falls, slides..."
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Plate Tectonics on Venus, 1993.
A look at the discoveries relating to Venus' geology with the Earth's crust including plates, rifts, etc.
2,475 words (approx. 9.9 pages), 14 sources, $ 87.95
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From the Paper
"Plate Tectonics on Venus?
The plate tectonic theory is now widely accepted as a unifying basis for the physical geology of the earth as a whole. Not only does it explain most of the tectonic phenomena on Earth, but a number of key points have been well substantiated by paleomagnetic and seismologic studies (4). Venus, Earth's nearest neighbor, and similar in size, density, and age (8) might be expected to have similar tectonic activity. Indeed Soviet and U.S. explorations of Venus during the 60's and 70's revealed several features that could be interpreted as past or ongoing tectonism (Fig. 1). These included large calderas and arachnoids suggesting volcanism, dome uplifts, low ridge belts on planes, high mountain belts, heavily deformed areas called tesserae, and the circular coronae unique to Venus (9). Now that the..."
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Playas, 1993.
An analysis of these bodies of water in the desert including characteristics, human uses, hydrology, types, salts, mounds and wind.
2,250 words (approx. 9.0 pages), 10 sources, $ 79.95
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From the Paper
"Inland Playas
Many terms have been used to describe playas. In general, a playa is a closed body of water which occurs in a desert environment Playa salinity ranges from high to solute saturated--some lakes being completely ephemeral. In all playas evaporation will usually exceed input. These lakes are distinguished according to the presence or absence of groundwater influx. Dry playas are periodically flooded by surface waters and tend to be floored by silt and clay. When groundwater lies between 1 and 3 meters from the playa crust, capillary movement may form a puffy surface. When groundwater discharges into a basin it creates a moist playa. Moist playas are characterized by salt crystallization that tends to be deposited in outer carbonate zones, middle sulphate zones, and inner chloride zones. Present..."
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Coastal Processes of the Great Lakes, 1993.
A look at the causes and effects of coastal processes of the Great Lakes, including water levels, human influences, erosion, waves, currents, shorelines and storm surges.
1,575 words (approx. 6.3 pages), 13 sources, $ 55.95
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From the Paper
"Coastal Process of the Great Lakes
The Great Lakes are a series of giant tubs linked by rivers and smaller lakes (Gorrie, 1988, p. 20). The flow starts in Lake Superior (the largest and deepest of the chain) and then passes through the St. Mary's River to Lake Huron and Lake Michigan (Gorrie, 1988, p. 20). Because these two are joined by the broad Straits of Mackinac, they behave as a single sea (Gorrie, 1988, p. 20). Their waters are connected to Lake Erie by the St. Clair River, Lake St. Clair and the Detroit River; the Niagara River connects Lake Erie with Lake Ontario (Gorrie, 1988, p. 20). Eventually, much of the Great Lakes' water egresses to the Atlantic Ocean through the St. Lawrence River (Gorrie, 1988, p. 20). In recent years, this system of waterways has attained some of the highest water levels recorded this century (Cobb, 1987 ...."
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