eCheat.com RSS Feedhttps://www.echeat.com/ How earth quakes are caused How Earthquakes Are Caused Author’s name Institutional affiliation How Earthquakes Are Caused An earthquake is the shaking of the surface of the earth when so much energy is submitted to the ground. According to (Pakiser & Shedlock, 2014), “the earth is made up of four major layers including crust, mantle, outer core and, the inner core while the crust and the upper part of the mantle make up a thin layer on the surface of the earth consisting of many pieces, tectonic plates”. On the other hand, the 2017-06-10T09:44:27.997-04:00 http://75.150.148.189/free-essay/How-earth-quakes-are-caused-45340.aspx chinese civilisation Student’s Name Professor’s Name Course Date Chinese Civilization The distribution of natural physical features and their location has a direct influence on population and the culture of a group of people. Such differences determine the unity and the duration of a civilization’s existence. China is a country whose ancient cultural practices and unique traditions have remained intact for many generations due to its geography. Its size and topography were the principal contributor to the country’s unique features, preventing invasions and foreign cultural influences. Like Mesopotamia and Egypt, the Chinese civilization is one of the most ancient ones on Earth. The peculiar location and a unique way of life have been one of the nation’s features since the establishment of the Han Dynasty more than two millennia ago (National Geographic n.p.). Thus, the country’s topography is the leading cause of differences in distribution and population in China, with more than ninety million people living in Shandong province characterized by mild coastal climate, while less than three million people inhabit Tibet due to its harsh mountainous weather (National Geographic n.p.). Such a disparity has caused certain differences in economic and social development. China’s distribution of natural physical features isolated it from any neighboring cultural influences. Thus, the country’s geography isolated it from surrounding civilizations and made it mostly dependent on its own capability (Bartsch n.d.). The rough terrain did not only isolate China from the outside world, but also posed an economic problem because most of the Chinese could not access essential commodities. Thus, the country remained separated from the outside world until the establishment of the “Silk Road” during the rise of the Han Dynasty (Bartsch n.p.). Apart from opening China to foreign influence, the Silk Road connected various part of the country, which paved the way for regional dissemination of different cultures and economic activities. Nonetheless, the Chinese people preserved the integrity of their traditions despite the interactions with the outside world. In fact, the new rout of trading did not encourage foreigners to venture into the interior of the country. For instance, one could travel through rainforests of grasslands and then encounter a desert or a mountain range. In addition, the early Chinese civilization lacked knowledge of the existence of influential Western countries. Thus, it made the Chinese people self-reliant in finding solutions to their problems. For instance, many innovations were made to improve agriculture; moreover, the discovery of loadstones, the invention of chariots and 2016-02-05T00:28:42.957-05:00 http://75.150.148.189/free-essay/chinese-civilisation-35167.aspx Rocks Introduction What is a rock’s favorite ice-cream? ROCKY road! What is a rock’s favorite song? We Will, We Will, ROCK You! Ok, ok, all jokes aside. Would you like to learn more about rocks and minerals? If you do, come along on my fascinating journey. (In an airplane.)There are many things to see and learn about on this trip. So, pack your bag and socks because we are going to learn more about rocks! We are turning on the oldies…Haha Minerals are natural compounds or elements of inorganic nature. There are 92 naturally occurring elements that have specific physical properties, definite chemical composition, and characteristic atomic structure. You can also find between 2,000 to 2,500 minerals in the earth’s crust. Minerals are formed in a positive response to their environment, most of them too deep for an observer. Environments in which minerals are formed far beneath the earth’s surface are plutonic igneous, pegmatitic, hot temperature vein, moderate temp. Vein, low temp. Vein and a metamorphic environment. Environments in which minerals form near the earth’s surface are groundwater, weathering, and sedimentary. Minerals are divided into groups on the basis of their composition. About one third of all mineral belong to the group silicates. Other groups are carbonates they includes calcite, oxide which includes magnetite, sulfides which includes pyrite, halides which includes halite, sulfates which includes gypsum, and phosphateswhich eapalite the mineral belongs to. The last group is every mineral that is a chemical element and is found their uncombined state. The elements include copper, silver, gold, and so on. The Rock Cycle describes the process the earth uses to recycle rocks. Yes, even rocks are recycled. There are three basic types of rocks: igneous, metamorphic, and sedimentary. The interesting part of knowing these names is that any one of the three types of rock can be changed into one of the other types. The names of the rock types refer to the way the rocks are formed. Igneous rocks are formed from fiery molten magma. Metamorphic rocks form under intense heat and pressure. Sedimentary rocks form by weathering. Get ready for a very rocky flight….Haha Igneous Rocks Igneous rocks are formed of magma, the molten form of the earth’s mantle layer. Igneous rocks can form above ground as lava spewing from volcanoes. But igneous rocks can also form below the surface. Pockets of magma get stuck in layers of the earth. As they get closer and closer to the surface, the magma slowly cools. Granite is an igneous rock that formed from a 2013-04-02T20:14:26.757-04:00 http://75.150.148.189/free-essay/Rocks-34842.aspx deforestration Deforestation is the clearing the land of forest or trees and it is increasing as a global concern. In recent years deforestation has risen to dangerous levels. This reason is mainly due to the fact that most people have no idea what deforestation is. Forests play a pivotal role in the 2012-05-18T03:25:44.453-04:00 http://75.150.148.189/free-essay/deforestration-34567.aspx Global Warming Global warming is a “heated” topic in modern society. It is a constant struggle to stop the unstoppable. Climate change has always happened, is happening, and will persist to happen until the end of the earth. The constant flux is due to the earth’s irregular motion around the sun. Fortunately for the rest of you, I have devised the plan of action that we 2008-12-27T20:38:35-05:00 http://75.150.148.189/free-essay/Global-Warming--33928.aspx The Importance of Coral Reefs The Importance of Coral Reefs Coral Reefs are one of the world’s most beautiful habitats. They are often called the “rainforests of the ocean,” because they support such a diversity of life. They are massive underwater structures formed by the limestone skeletons of tiny invertebrate animals. These beautiful underwater structures are the largest and most diverse biological structures on earth, take thousands to years to form, yet they are being destroyed at an alarming rate. Coral Reefs are built by accumulated skeletons of tiny animals which are mostly corals and plants. These plants are mostly coralline algae. They are built near the surface in tropical seas. When sunlight reaches the appropriate area, corals will start to grow. Over the years coral builds a reef that fringes the shoreline. This is called a fringing reef. Fringing reefs are separated from the land only by shallow water. If a reef grows farther from land, it is a barrier reef. These reefs are separated from the land by a larger lagoon. The Great Barrier Reef is the largest biological structure on earth covering over 2000 kilometers on the east coast of Australia. Atolls, on the other hand, are formed far offshore and they make a ring-shaped reef that close a circular lagoon. Occasionally a coral reef is lifted from the water making it a coral island. The corals are made up of tiny organisms called polyps that grow together to produce the skeletons. Polyps are made up of two cell layers, the epidermis and the gastrodermis. They contain mesentery filaments to capture food, a pharynx and the columella which is found below the mouth. It is surrounded by a ring of tentacles which it uses to catch food floating in the water. Corals also get their food from single-celled plants called symbiotic algae which makes food from sunlight. The skeletal wall that surrounds the polyp is called a theca. There are two types of coral. The perforate have porous skeletons with connections between the polyps and the imperforate have solid skeletons. Corals have branches and looks just like plants and grow very slowly. If they are broken or killed by pollution, it will take the reef many years to recover. Algae is the plant that makes most of 2007-04-25T19:35:39-04:00 http://75.150.148.189/free-essay/The-Importance-of-Coral-Reefs-33130.aspx Bronfernbrenner's Ecological Systems Theory Bronfernbrenner's Ecological Systems Theory The prevalence of violent crime in North America, including Canada, can be attributed to a deadly combination of cultural values, economic conditions, and biological and environmental factors. These factors are part of Bronfenbrenner’s Ecological Systems Theory, which explains how the interaction of different parts of an individual’s life can shape and form who they are and how they act (text p7). Violent crime, specifically homicide, suicide and accidental death by a gun, are more prevalent among young men between the ages of 15 and 35, than by older men or women of any age (text p. 483-484). The combination of Bronfenbrenner’s micro system (family, peer group, etc.), exosystem (community, education, etc.) and perhaps most of all the macro system (cultural values, economics, etc.) can explain why young men are more susceptible to commit and be a victim of violent crime (text p. 483). Young men are usually brought up in a North American home believing they have to prove themselves as a “man’. The cultural idea of what a “man” should be includes strong, dependable, a protector for the family, etc. This pressure leads many young men to think they need to use their aggressiveness to prove they are a “man”. This could include drive by shootings on rival gangs, fist fights with another young man who resembles an “enemy” to prove their worthiness of the title. These pressures inhibit young men from developing self-restraint, self-respect, and respect for others’ opinions and beliefs (text p. 486). This pressure of the macro system on the micro system explains the never-ending cycle. One man raised by parents influenced by cultural norms, to raise their son to fit the socially constructed form of a man. Then the boy grows up to raise his son(s) in the same socially constructed way, creating violent young men in every generation. One of the more prominent concerns today is the debate around gun control and its relatedness to violent crime. By comparing Canadian and American statistics the different effects of the micro system (family) and exosystem (community) can be seen. In the United States is more accepted by the family, community, and government for civilians to posses a gun for personal and property protection. The Canadian laws prevent citizens from owning handguns unless they belong to a 2007-04-23T03:34:12-04:00 http://75.150.148.189/free-essay/Bronfernbrenner-s-Ecological-Systems-Theory-33083.aspx The Future of Planet Earth The Future of Planet Earth Americans have increasingly divulged themselves in over-consumption. This escalating desire for physical goods is initiating the depletion of our resources and the destruction of our environment. The people of the United States, in their quest for material products, are causing catastrophes, such as the greenhouse effect, hazardous wastes, and a growing number of landfills. This in turn pollutes the planet and catalyzes global warming. Greenhouse effect has been reeking havoc with the natural balance of the planet. The major agents contributing to the greenhouse effect are the product modern society has created for our pleasure. In reality, these products are causing the United States, as well as, the rest of the world, major difficulties. AAA is one company that is using ‘affluenza’ to its benefit. AAA was against the 1990 Clean Air Act, one of the most important environmental laws of the decade. A press release from its government and public affairs headquarters in Washington, D.C., claimed that the bill would “threaten the personal mobility of millions of Americans and jeopardize needed funds for new highway construction and safety improvement” (Rivlin 14). Instead of promoting legislation that would improve the quality of our environment for everyone, AAA would rather build more highways so more people will purchase automobiles and insurance and therefore further pollute our air supply. In addition, the effects of the greenhouse gases in the atmosphere have caused the depletion of the polar ice caps. The greenhouse effect causes the planet to warm, increasing the climate of the Arctic region and causing the glaciers to melt. The main cause for the rapid warming of the Earth is industrial pollution. The United Nations Intergovernmental Panel on Climate Change has warned the world of the consequences of pollution such as: the melting of glaciers and polar ice caps, leading to rising sea levels. It predicts more extreme droughts, floods and storms and significant changes in the functioning of critical ecological systems such as coral reefs and forests. Warmer and wetter conditions would increase the spread of infectious diseases such as malaria and yellow fever. And the inundation of low-lying islands and coastal areas could lead to the displacement of hundreds of millions of people. The climate panel’s report says that sea-level rise could cause the disappearance of vast 2007-04-23T03:27:37-04:00 http://75.150.148.189/free-essay/The-Future-of-Planet-Earth--33080.aspx Morality And The Environment Case Study Morality And The Environment Case Study 1.1) Immediate: The immediate issue in this case study is whether or nor Erica Mann who is the coordinator for the western division of the Federal Wildlife Agency and the chairperson for the International Herpetological Society should endorse an artificial habitat proposed for the relocation of the endangered Sonoran Desert Snake. The reason that snake would have to be relocated is because a proposal to build a damn that would ruin the snake’s habitat is being considered. The dam is needed to support Arizona’s agriculture and mining industries. This dam would flood the snakes habitat and eventually force it into extinction. At the same time Erica is aware of the fact that the new environment proposed for the snakes would not necessarily guarantee their survival. In fact the report by the IHS contradicted the report from the FWA and stated that the new habitat would be sufficient for the snake’s survival. Erica is aware of the fact that this report only exists because of political pressures and that it is not entirely accurate or truthful. In fact, Erica herself is being pressured to back the report which she knows is inaccurate. She must decide whether or not she should give in to the political pressure or instead do what she feels is right and save the snake. 1.2) Basic: Can you justify destroying a particular species of animal in the interest of human progress or advancement? Personal Experience 2.1) Personal Narrative: My personal narrative has less to do with the issue of Endangered Species than it does with situation that faces Erica. There is a line in the case study where Erica’s superior encourages her to fight the battles she can win. This is what my personal narrative has to do with. As I have grown up and matured towards adulthood these last eight or so years, I have learned some important life lessons. One particular lesson is that I need to pick my battles. Although I have often been adamant about many different issues, I have learned that I can’t always get what I want and that many times I only waste my own time fighting a battle that can’t be won. Throughout my teenage years I consistently butted heads with my parents over many different things. 2007-04-23T03:15:17-04:00 http://75.150.148.189/free-essay/Morality-And-The-Environment-Case-Study-33076.aspx Deforestation Issues in Brazil Deforestation Issues in Brazil In recent years one of the biggest threats the world as a whole faces is the destruction of our environment. The destruction of the Brazilian rainforest is probably the most important issue that should be taken into consideration because it is the cause of other major ecological problems we are facing such as: global warming, the depletion of our ozone layer, and noticeable climate changes around the world. Brazil's deforestation problem has turned into earth’s deforestation problem. Experts say that not too long ago 14 % of the earth was covered with rainforests. Today only 6% remains and everybody focuses their attention on Brazil because 30% of the remaining rainforests are found in that country (Rain-tree). Deforestation is so dangerous because much of the carbon dioxide that all countries produce is turned into oxygen in the rainforest through the process of photosynthesis. Experts say that 20% of the earth’s oxygen is produced in the Brazilian rainforest. It is estimated that 90% of all animal and plant species live in the Brazilian rainforest so extinction is another major issue (Rain-tree). The money that deforestation brings to the Brazilian government is a huge motivator since it is a developing country. There are several ways and reasons for which rainforests are destroyed. The major cause of deforestation is logging. The forest is most valuable for its timber so its preservation would cost a lot of money. Commercial loggers destroy huge parts of the forest to reach the trees they want. Trees are brought down and along with them their vines and lianas, which are connected to other trees. When these come down, along come large canopies of green formed above the ground by these vines and lianas. The removal of the trunks cause extra damage since they are carelessly pulled out of the rainforest, destroying and damaging anything in their path. The large machinery compacts the fragile soil with their large tracts, making it very difficult to regenerate. Noise pollution and the destruction of the zone frighten animals living in the area, making them flee to other parts. Commercial loggers make roads to reach other parts of the forest easier. A road connecting point A to point B will disrupt plant and animal life anywhere near it. The roads are then used continuously and animals are forced elsewhere. What most hurts the forest about logging is local people without land 2007-01-11T04:06:04-05:00 http://75.150.148.189/free-essay/Deforestation-Issues-in-Brazil-32343.aspx The Geology of Mt. Kilauea The Geology of Mt. Kilauea Mt. Kilauea is one of the world’s most active volcanoes. The Hawaiian name “Kilauea” means spewing or much spreading. Located on the big island of Hawaii, it has had 61 major eruptions in its huge lifetime. Mt. Kilauea has an elevation of 4,200 feet and has an area that consists of 552 square miles. Common questions asked about Kilauea are: What kinds of forces cause Mt. Kilauea erupt constantly over a long period of time, and why don’t any other volcanoes do this? In response, the answers to these questions are both tied together with the volcanoes ‘hot spot’. A hot spot for this Hawaiian volcano is located beneath the island and provides magma for eruptions. This hot spot carries constant and steady supplies of magma for the mountain to spew. Not much is known about these “hot spots” beneath the surfaces of these volcanoes. Since 1983, Mt. Kilauea has been a continuous lava-spitting volcano. Kilauea is approximately 23,000 years old and is considered to be a shield volcano, a composite eruption with basaltic magma. Hundreds of earthquakes happen beneath the volcano and island’s surface. These earthquakes are defined as volcanic activity earthquakes. Some of these quakes have been large enough to send and generate tsunamis or tidal waves. The largest earthquake’s magnitude was measured at a 7.9. This quake made a 15-meter tsunami on April 2nd, 1968 and killed 81 people. Volcanoes have formed the basic landscape of the Hawaiian Islands. The volcanoes have built this state up to 4,200 feet in elevation! The lava flows generated by Mt. Kilauea have caused mass destruction to Hawaii by burning down houses, cars, and villages. Eruptions, spitting up lava that can exceed 1,ooo degrees, burn anything in its path. This fiery nature-made substance boils into lakes and streams, killing many fish and incinerating wildlife. Sometimes Kilauea’s lava spouts can get up to 200-300 meters high. Often Kilauea’s lava spouts cause huge rocks to fall from the sky. This happens by the lava flying and hardening in mid-air and finally falling to the ground. One of these “flying rocks” has been found up to 3 meters in diameter. Researchers and scientists find Kilauea to be one of 2006-12-29T15:16:38-05:00 http://75.150.148.189/free-essay/The-Geology-of-Mt_-Kilauea--32149.aspx Earthquakes Volcanoes and Mountain Ranges Earthquakes, Volcanoes and Mountain Ranges Volcanoes, earthquakes and many of the great, in size, mountains (the Himalayas, Rockies, Urals, Alps, and the Appalachians) will all be marked on my map at some point in this project. Now just let me tell you some interesting facts about some of these topics. Since recorded history, 550 volcanoes have erupted on the earth’s surface, but even far more have erupted unobserved on the ocean floor. The enormous Himalayas and many other great mountains are known to be young Fold Mountains. Young, because these have been formed relatively recently in the earth’s history, compared to other mountain ranges like the Aravallis in India and the Appalachian in the USA. These are known as fold mountains because they extend for 2500 km in length in a series of parallel ridges or folds. This information has been found using a theory that took place in 1912, by a German meteorologist, named Alfred Wegener. This theory is the Theory of Continental Drift. In the real ocean, plenty of natural disasters can trigger a similar event. Caused by a paddle-effect of an earthquake, underwater volcano or even an asteroid, sunamis are enormously dangerous stealth waves that travel vast distances across the ocean. Is there a pattern or repetitiveness in certain areas on earth where volcano’s, earthquakes and mountain ranges commonly appear? a) Earthquakes are most likely to occur where tectonic plates meet or hit each other. b) Volcanoes are most likely to occur where tectonic plates split apart or separate from each other, allowing magma to come up through the cracks. c) Mountain ranges are most likely to occur where one plate slips under another allowing the magma to come up or collide and push up on each other. The materials that were used during this project were Science and Technology, The Complete Atlas of the World, the computer, the Internet, pens and pencils. The different steps I took at conjuring up information to apply to the work that has been assigned, was to: Step 1) Check in my science textbook, to find the longitude and latitude for each of the huge volcanoes and earthquakes that have happened in history and mark them on my map. Step 2) Check in my atlas, to find the huge mountain ranges that still stand today and mark them on my map. Step 3) 2006-11-02T15:52:38-04:00 http://75.150.148.189/free-essay/Earthquakes-Volcanoes-and-Mountain-Ranges-31674.aspx Precipitation Levels in California Caused my El Nino Problem The El Nino and La Nina storms bring up very serious and harmful effects of the planet. What happens is that there are major temperature changes in the East Pacific Ocean. Once the temperature starts to change rapidly, there is more warm water than cold water increasing water levels in areas of the world. It causes an un-normal amount of water in certain places in the pacific. During El Nino a mass of water lands on western South America, Mexico, and Western United States. This extra amount of water kills animal’s habitats, loss of crops for local farmers, loss of fish, mud slides, and flooding. All these are dangerous to humans and animals alike. Hypothesis During El Nino, there is an un-normal amount of water pushing on to land. This also creates large amounts of rain. Using my data chart of info on precipitation levels in North-West California through 1969-1979 I will be guessing which years have had El Nino years. My guesses are; December 1969, Late January 1975, and December 1978. I took my three highest points of the graph and looked down to the month and year then guessed that time period. Methods During this project I was looking for either California or South American precipitation levels for about 10 or 20 years. I searched for some data in those areas and from 1970-1980. I found that data and graphed it using a computer program. I ran into some difficulties entering in the dates because it was not the right type of method. I had to redo it using their methods of charting Month and Year. After that I read searched info on wikipedia.com, an online encyclopedia; I found some great info about La Nina and El Nino. Data The info that I found in the raw data was very similar in most years but also rose dramatically in others. At first I was interested in yearly totals. Through those ten years I found that the most precipitation through 1969- 1979 in California was 78.55 inches in 1974. The average amount of rainfall from 1969-1979 was 55.24 inches. The most amount of rainfall in a month was in January 1978 with 20.83 inches of rain. So the 1976-1977 El Nino might have carried over into the New Year. These are the 2006-09-05T21:22:46-04:00 http://75.150.148.189/free-essay/Precipitation-Levels-in-California-Caused-my-El-Nino-31432.aspx I am the Mekong River I am the Mekong River From my humble beginnings in an ice cave high in the Tibetan Himalayans, I wind 2,600 miles through remarkable years of history. I am known by Asian peoples as the “holy river.” I have seen war and hunger. I will now tell of who I am and who I know. I am the tenth largest river in the world. My course runs through China, Laos, Thailand, Cambodia, Vietnam, and on to the South China Sea. I provide life-giving resources for countless people and wildlife. My history is long and diverse. Early man inhabited my banks using my waters for nourishment. From the fifth to the eight-century primarily the Tai inhabited me. By the 13th century the Tai people occupied most of the my valley and grew from my waters with their staple food of rice. The Tai eventually formed a country, Thailand. As for foreign explorers, I was not “discovered” (by western standards) until 1886. It was difficult to navigate my waters because of my pesky Knong Waterfalls. In 1886 six Frenchmen were trying to establish a trade route. Finally they realized my falls were unbearable so they built a railway across the falls. During the 10th century, however, the Vietnamese began noticing how well the Kingdom of Champa was doing with my rich waters and soils. After all, I am considered to be one of the world’s richest rivers in terms of mineral laden sediments. I give all the water for irrigation not only the rice fields along my course, but also many fruits and vegetables. Currently I provide well over half of all the rice grown in Vietnam. Sediments from me provide food for one of the worlds most diverse fisheries. So it is no wonder that Vietnam began to want a piece of me. Here is where the years of anguish started. I would no longer be the carefree peaceful waters I was in past history. Humans began to complicate everything. The Vietnamese captured the Champa capitol, and destroyed the magnificent capitol over the Mekong delta. This was only the beginning of many wars and violence I would be witness to. In 1953 the French battled with Vietnam to take control of my middle and Lower River. In 1957 the U.N. started development to control flooding. Flooding my natural life cycle…they had no idea what they had put in motion. They meant well, 2006-08-06T21:49:26-04:00 http://75.150.148.189/free-essay/I-am-the-Mekong-River-31084.aspx Understanding Characteristics of Earthquakes Understanding Characteristics of Earthquakes Earthquakes are happening almost everyday all over the world. Most of the time earthquakes are not strong enough to be felt by people, but the shaking caused by an earthquake is recorded by a seismogram. These are located all over the world at different points. Only occasionally will a larger magnitude earthquake strike and cause damage to the region. Around the world there are many faults, depending where these faults are plays a major factor in determining where an earthquake will happen. It is these faults that are the reason for earthquakes. The type of fault will also determine how often an earthquake will happen. A mid-ocean ridge occurs under the sea at a divergent boundary. This is where two plates are been pulled apart because of tension. This then allows new oceanic crust to be made in the divergent boundary, as magma rises and eventually sets on the sea floor. If the plates on either side of the divergent boundary continue to spread then the ocean slowly becomes larger in width, a process called seafloor spreading. Mid-ocean ridges are characterized by a crack like valley at the divergent boundary. This crack like valley is caused by the tension pulling the plates apart, causing normal faulting to occur a number of times in the divergent boundary. It is these normal faults that are the cause and therefore the origin of earthquakes at divergent boundaries. When the tension pulling apart the two plates becomes too much then the oceanic crust will fracture. This fracturing is caused by many normal faults happening as shown in the diagram. The normal faults happen because the crust is been extended. When the tension becomes too much the faults slip vertically. They move a large distance in a relatively short space of time, this is the cause of the earthquakes at divergent boundaries. Divergent boundaries mostly occur on the sea floor and therefore the earthquakes that happen at these boundaries are distributed along the boundary. This means that the distributions of earthquakes at divergent boundaries are at shallow depths, where the crust is been pulled apart. The earthquakes happen at shallow depths because the normal faulting occurs near the sea floor, as a result of the tension. The normal faults are the cause of the earthquakes at these divergent boundaries. The seafloor sees the most intense tectonic 2006-08-01T19:07:21-04:00 http://75.150.148.189/free-essay/Understanding-Characteristics-of-Earthquakes-30964.aspx Theory Of The Earth from The Edinburgh Review, January 1814 Theory Of The Earth from The Edinburgh Review, January 1814 In giving to the treatise here announced the name of an Essay on the Theory of the Earth, the Editor has taken a liberty that is certainly not warranted by the original. The title of the French work makes no mention whatever of the theory of the earth. The fact is, that M. CUVIER having published, in the Annales de Museum, a succession of memoirs on the fossil remains of animals found in the strata around Paris, (of which an account was given in the 20th vol. of this Journal), was very naturally led to extend an inquiry, that became ever moment more interesting, to the fossil remains of land animals, wherever they had been found. His subject being thus enlarged, he has united the parts of a most ingenious and laborious investigation, in one work, comprehending four volumes in quarto, under the title of Recherches sur les Ossemens Fossiles des Quadrupedes. To this valuable and interesting book he has prefixed a Dissertation, (Discours Preliminaire), the same that appears here as an Essay on the Theory of the Earth. We are not sure that the author himself will be very thankful for this change of appellation. The preliminary discourse is a general view of the conclusions derived from certain animal remains, compared with the mineral beds in which they are contained, and with the principles of comparative anatomy. This subject, though of great importance, and of no small extent, is yet of too limited a nature to be regarded as a theory of the earth. A name that would have more exactly described the work, without departing from the conciseness essential to a title-page, might easily have been devised. Considerations, for instance, on the Fossil Remains of Quadrupeds, would have been a title much more appropriate. This translation has been made with singular expedition. The work was received about the middle of last summer; and the translation made its appearance in the beginning of winter. It seems, notwithstanding this haste, to be executed not only with fidelity, but with some degree of elegance; and the editor, Professor Jameson, has added notes, besides giving a very distinct and concise view of Cuvier's principal geological discoveries, which cannot fail to be very acceptable to those who have not an opportunity of perusing the large work and which will be found very 2006-07-25T12:50:26-04:00 http://75.150.148.189/free-essay/Theory-Of-The-Earth-from-The-Edinburgh-Review,-January-1814-30632.aspx Understanding the Sky to Predict the Weather Understanding the Sky to Predict the Weather If you know where and when to look, you can treat yourself to a colourful display of atmospheric haloes, spots and pillars. These images can tell you something about the clouds overhead and possible changes in the weather. All of these images are created by light shining through cirrostratus clouds. These clouds occur at an altitude of 6,000-12,000 metres. They appear as a thin sheet or layer (strata) that is pure white. The layer of cloud is so thin (only 100-450 metres) that is doesn't obscure the sun or moon, so you should be able to see your shadow. Cirrostratus is made of many types of ice crystals. However, four crystal shapes are responsible for producing most of the commonly see haloes-plate crystals, columns, capped columns and bullets. The most obvious halo is found around the sun. If the layer of cirrostratus is extensive, you'll see an entire ring. Within the layer of cloud, sunlight is striking and passing through the sides of randomly-oriented ice crystals. As the sunlight passes through each crystal, the light changes direction, or refracts. The radius of the hale depends on the amount of change in the direction of the sun's light. Usually this is 22 degrees. Since the sun is 1/2 of a degree across, the radius of the halo is 44 sun-widths. Occasionally you may see a second halo at 46 degrees from the sun (that is, with a radius of 92 sun-widths). This is produced by sunlight passing through both the side and bottom of each crystal. Moonlight will also produce a halo, around the moon, with the proper layer of cirrostatus. Another common optical effect is known as "mock suns" or "sun dogs" or "parhelia" (Greek for "with the sun"). These bright spots on either side of the sun, outside of the halo, occur when sunlight passes through the sides of capped columns, bullets and plate crystals, when these crystals are arranged with their sides vertical. The crystals wobble, diffusing and smearing the colours of the mock sun. You can see haloes and mock suns more clearly if you block out your view of the real sun by holding your hand in front of it at arm's length. Another spectactular optical effect is the 2006-06-12T18:45:39-04:00 http://75.150.148.189/free-essay/Understanding-the-Sky-to-Predict-the-Weather-29346.aspx The Importance of Celebrating the Environment on Earth Day The Importance of Celebrating the Environment on Earth Day Earth Day is something you should know more about and be more involved in because of its intriguing history, its wonderful purpose, and the many things you can do to help. It is simply nothing short of amazing that earth day is still making an impact on the United States today. I feel that Earth Day was a wonderful thing to start and I think that it has helped the USA stay a cleaner place on this earth. It is amazing that a day for cleaning our country that originated thirty years ago with hippies and it is still around today. Earth Day has a very interesting history that everyone should know about. Senator Gaylord Nelson was the founder of earth day. Earth Day’s main idea was conceived over seven years starting in 1962. President Kennedy tried to stop the anti-Vietnam War “teach-ins” and use some hippie power to a good cause by starting Earth Day. The President went around the country talking of how to keep our nation clean while congress accepted the idea of an “earth day”. The plan was now starting to work; now people had a new subject to talk about and now it was cleaner rivers and air, not Vietnam. The first Earth Day was celebrated on March 21st 1970. The very interesting history of Earth Day is something that everyone should know about. The purpose of Earth Day is to help to keep our grass green and our skies blue with more trees and less pollution. Earth Day was made for another reason, to focus the nation on its ecological problems and not its ones with Vietnam. Earth Day has lost its first reason of Vietnam and now it is out there so that people are more aware of what they are actually doing when they throw a candy wrapper out the window, or leave their Styrofoam cup sitting on the sidewalk. People need to use their streets and sidewalks and we cannot have them to be operating with massive amounts of trash on them. Keeping our national parks clean is another concern of Earth Day, volunteers go out to clean national parks such as Yellow Stone on Earth Day so that foreigners don’t think that all Americans are pigs. Most of all, Earth Day is a way to restore patriotism in American Citizen’s hearts; throwing a cup 2006-06-11T20:14:54-04:00 http://75.150.148.189/free-essay/The-Importance-of-Celebrating-the-Environment-on-Earth-Day-29240.aspx Disruption of the Food Chain as a Result of O-Zone Depletion Disruption of the Food Chain as a Result of O-Zone Depletion Ozone is a form of oxygen that is a human-made pollutant in the troposphere but a naturally produced, essential component in the stratosphere, which encircles our planet some 6 to 28 miles above the surface. The stratosphere contains a layer of ozone that shields the surface from much of the ultraviolet radiation coming from the sun. If ozone was to disappear from the stratosphere Earth would be uninhabitable for most organisms. The primary cause for this substantial ozone loss is a group of compounds called chlorofluorocarbons (CFCs). CFCs have been used in aerosol cans as propellants, as coolants in air conditioners, and refrigerators, as foam blowing agents for insulation as well as packaging like styrofoam. Other compounds that may attack the ozone include: halons, methyl bromide, methyl chloroform, and carbon tetrachloride. As CFC’s drift up into the atmosphere the UV radiation breaks them down, releasing chlorine. Bromine is released by the breakdown of halons and methyl bromide in the atmosphere. Under certain conditions in the stratosphere, chlorine and bromide are capable of attacking ozone and converting it to oxygen. UV radiation has the potential to penetrate tens of feet into clear ocean water. As we know, the entire marine food chain is based on phytoplankton, which float on or near the top of water bodies. Phytoplankton are the producers, they are on the first trophic level in the aquatic food chain. Phytoplankton is extremely sensitive to UV levels; scientists have found that phytoplankton decreases mobility, changes in photosynthesis and enzymatic reactions under UV radiation. Studies in Antarctica, directly under the ozone hole, found the rates of phytoplankton production to be depressed relative to similar areas. With a decrease of Phytoplankton in the water other fish will have to rely on other food sources, or they too will begin to decline. Higher levels of ultraviolet radiation could also reduce global plant coverage, thus enhancing climatic change. Plants have shown direct effects of UV are on photosynthesis and growth. More subtle changes related to UV are a delay in flowering, shift in distribution of leaves, changes in leaf structure, or a change in plant metabolism. The effects of this are wide spread; shifts in plant population and bio-diversity could be dramatically changed. 2006-06-11T19:18:39-04:00 http://75.150.148.189/free-essay/Disruption-of-the-Food-Chain-as-a-Result-of-O-Zone-Depletion-29211.aspx Broad Analysis of Igneous Rocks in Earth's Geology Broad Analysis of Igneous Rocks in Earth's Geology Out of the three different types of rocks, 2006-06-06T14:39:20-04:00 http://75.150.148.189/free-essay/Broad-Analysis-of-Igneous-Rocks-in-Earth-s-Geology-29064.aspx Crude Oil Crude Oil Petroleum also known as crude oil, naturally occurring oily is a bituminous liquid composed of organic chemicals. Petroleum means rock oil, from the Greek petros (rock) and oleum (oil). It occurs in the earth in liquid, gaseous or solid forms. The term is usually restricted to the liquid form, commonly called crude oil but as a technical term it also includes natural gas and the viscous or solid form known as bitumen. Petroleum is a complex mixture of organic liquids consisting of hydrocarbons (compounds composed mainly of hydrogen and carbon with some nitrogen, sulphur and oxygen). Petroleum is formed under the earth’s surface by the decomposition of marine organisms. The remains of tiny organisms that live in the sea, that are carried down to the sea in rivers and of plants that grow on the ocean bottom are enmeshed with the fine sands and silts and settle to the bottom in quiet sea basins. Such deposits that are rich in organic materials become the source rocks for the generation of crude oil. The process began millions of years ago and still goes on today. Trapped in fine-grained sediments, the remains are cooked by the heat of the earth to produce oil and gas. Once the petroleum forms, it flows upwards in the earth’s crust because it has a lower density than the constituents of the earth’s crust. When petroleum is trapped, a reservoir of petroleum is formed. Exploration is probably one of the most important steps of producing oil. In order to find oil underground geologists, geophysicists and exploration engineers attempt to search for it so that petroleum-producing companies can drill for it. They must search for a sedimentary basin in which shales rich in organic material have been buried for a sufficient long time for petroleum to form. The petroleum must also have had an opportunity to migrate into porous traps that are capable of holding large amounts of fluid. The occurrence of crude oil in the earth’s crust is limited both by these conditions, which must be met simultaneously, and by the time of span of tens of millions to a hundred millions years required for the oil’s formation. These people have many tools at their disposal such as Jack Ups, Semi-submersibles and Drill ships to assist in identifying potential areas for drilling. Exploration mostly involves luck, with one out of ten drilling becoming commercial successes. When crude oil is 2006-02-12T21:39:19-05:00 http://75.150.148.189/free-essay/Crude-Oil--28481.aspx Acid Rain Pollution Acid Rain Pollution Acid rain pollution comes in various forms. Whether it’s toxic waste, CFC’s, or sewage, they are all hazardous to the earth. These can deplete the earth and it’s inhabitants of resources, causing a harmful change. A product of pollution is acid rain. We shall see that acidification is harmful to all forms of life. Acid rain is any form of precipitation that is polluted by sulphur dioxide (SO2), and nitrogen oxides (NOX). This acid precipitation can be in the form of rain, snow, sleet, fog, or cloud vapors. The acidity of substances dissolved in water are measured by their pH levels. Normal precipitation pH levels fall between 5.0-5.6.2 When levels fall below these numbers, then the precipitation is said to be acidic. There are two ways in which acid deposition can form. The first way occurs when nitrogen oxides and sulphur dioxide land on the Earth’s surface, and interact with frost or dew. The second way takes place due to the oxidation of nitrogen oxides or sulphur dioxide gases that are released into the air.3 Since it may take up to several days for the gases to be altered into their acid counter-parts, the pollutants can travel miles away from their original source. Emissions of (SO2) are responsible for the majority of the acid deposition, which falls to Earth. When we burn coal, we are releasing (SO2), into the air, since coal is slight made up of sulphur. Volcanic eruptions can add a great deal of sulphur into the atmosphere. Everyday organic decay adds sulphur into the air as well. (SO2) can hit the Earth’s surface in dry forms or wet forms, by undergoing the following reactions: (SO2 + H20 *** H2SO3) (SO2 + ½O2 *** SO3 + H2SO4)2. Human activity is the major cause for nitrogen oxides’ presence in our atmosphere, such as forest fires and the combustion of oil, coal, and gas. The other causes are due to nature. Lightning, volcanic action, and bacteria in soil are just to name a few. The following chemical reactions show how acids of nitrogen form: (NO2 + ½O2 *** NO2) (2NO2 + H2O *** HNO2 + HNO3) (NO2 + OH *** HNO3)2. Acid rain can affect plant life directly when the surface of leaves and needles come into contact with acid vapor or fog. This causes a reduction in the tree’s ability to withstand the cold. A direct result 2005-12-26T03:43:51-05:00 http://75.150.148.189/free-essay/Acid-Rain-Pollution-28260.aspx The Forest Resources of Canada The Forest Resources of Canada The topic that we have been assigned is chapter twenty-three, The Forest Resources of Canada. This extensive chapter covers the many facts of Canadian forests, the types of trees and areas, the necessity of this industry and the methods of harvesting trees. This topic also includes, the different types of mills, the many threats to the forests, changes in the industry and three very controversial topics. The dangers and value of the forests are unknown to many, but are subjects of significant importance. Forests cover forty-two percent of Canada’s total area, which is 4 187 820 squared kilometres. Canada, along with Brazil and Russia, has more forests than any other country in the world. Canada’s forests consist mainly of two types of trees: coniferous and deciduous. Sixty-three percent of the forests contain coniferous trees, which are trees with cones and needles such as the pine and spruce. Deciduous trees lose their leaves each year and are mainly poplar and white birch. They cover twenty-two percent of Canada’s trees. The rest of the forests are made up of a variety of different species, which covers fifteen percent. There are two areas of trees: commercial and non-commercial. Commercial forests are found in warm, wet areas where trees commonly grow rapidly. These areas are close to methods of transportation and are easily accessible by roads. They contain trees that are usually harvested unlike non-commercial forests. Commercial forests have been divided up into five forest regions, which are: boreal, taiga, west coast, montane and mixed. Non-commercial forests are unlikely to be cut down because they are unreachable since they are located in the northern parts of Canada. They often grow slowly and do not achieve their maximum growth because of low temperatures and low precipitation levels. To harvest them would be impractical, for the costs of travelling to remote areas would be expensive and a profit would not be earned for the trees may not be mature. The forest industry is greatly relied on, by many Canadians. Approximately one in every sixteen jobs depend on it and it provides three hundred and sixty thousand direct jobs. If these forests were to ever vanish many Canadians 2005-11-05T22:34:47-04:00 http://75.150.148.189/free-essay/The-Forest-Resources-of-Canada-28090.aspx Coastal Erosion Geology Research Report Coastal Erosion Geology Research Report The topic that I chose to do my geology extra credit paper on is coastal erosion. There are many different types of coastal erosion and are all very important. There has been a lot of research done on coastal erosion and all have been very helpful in understanding it clearly. The first attempts to stop coastal erosion were to build sea defenses, and this has been going on for many decades now. Researchers first thought the attempts were successful, but after several years it was understood that the power of the sea was too powerful for any kind of human defense. Huge costs were involved, but the only thing that produced was protection. Many methods around the British Isles have taken place in the last fifty years only to occur in many different failures. It is very rare to find a coastline with a decrease in the rate of erosion after many years after defenses have been put into place. The fact that the erosion process actually speeds up in the different places that these defenses have been set up comes from different research. Coastal erosion is the natural process of erosion, transportation, and deposition. Interfering with these natural processes could be the blame for the rise in erosion on the coasts of some areas. One way that has been helpful in the management of coastal erosion is the building of groins. Groins have been built out to sea in many areas of the British coastline. The reason for doing this is to trap material and thus slow down the rate of longshore drift. The downside to these groins is that they have been blamed for the rise in erosion rates further down the coast. People are complaining that the erosion occurs more rapidly after these groins have been made. One of the only ways to stop this is to just start building more groins. There is a coastline in Humberside where erosion is taking place about two meters per year. There is a strong action of longshore drift taking place along this coastline. Over many many years, this has caused a spit to form on the southern tip of Holderness, which is called the Spurn Head spit. The spit is over four kilometers long and 100 meters wide. 2005-08-28T06:30:47-04:00 http://75.150.148.189/free-essay/Coastal-Erosion-Geology-Research-Report-27798.aspx The History of Glass Glass The history of glass is an old, mysterious story. Natural glass has existed since the beginning of time. Obsidian is a natural black volcanic glass that was used by primitive people for tools, knives, arrowheads, and decoration. It is uncertain when and where man discovered combining enough heat with the right materials could make glass. Archeologists have dated the oldest man-made glass to about 7000 B.C. Glass’s natural properties are what create its sparkling brightness and often-translucent form. Glass’s history has many uncertainties. The New Book of Knowledge states that according to the Roman natural historian Pliny (A.D. 23-79) glass was discovered along the coast of Syria. According to this account, some seamen stumbled upon glass when cooking there dinner. Since they could not find big enough rocks to place their cooking pots on, they used blocks of niter, a form of soda. After their fires died down, they found that the niter had fused the sand underneath into a glassy substance (“Glass”). After this discovery the craft was born. Early glass articles consisted mainly of small beads and charms. Glass was considered as a gem, valued equally as a precious stone. Not until the discovery of the blowpipe was glass changed from a luxury product into something that lower class people could afford and enjoy (“Glass”). Glass is one of a few products that can be made from inexpensive raw materials. According to The New Book of Knowledge glass has a base of pure silica sand, which is composed of the mineral quartz, a compound of elements silicon and oxygen (“Glass”). In order to allow the sand (former) to melt more readily at a lower temperature of about 2600 degrees Fahrenheit, fluxing agents need to be added, like Soda ash, potash, and lithium carbonate. Fluxes however, make the glass chemically unstable, making it liable to dissolve in water or form unwanted crystals. Therefore stabilizers are also needed to make the glass uniform and keep its special structure intact. These include limestone, litharge, magnesia, barium carbonate, strontium carbonate, and zinc oxide (The Glassy State In-Brief Par 6-8). Other substances can be added to adapt glass for special purposes. Because of the iron present in all sand, glass naturally has a greenish cast. In order to decolorize the glass selenium (a non-metallic element somewhat like sulfur) needs to be added. This 2005-08-15T00:43:48-04:00 http://75.150.148.189/free-essay/The-History-of-Glass-27644.aspx Environmental Report: Hurricanes and their Tendencies Environmental Report: Hurricanes and their Tendencies According to the National Hurricane Center, a hurricane releases heat energy at a rate of 50 trillion to 200 trillion watts, which is equivalent to the energy from exploding 10 megaton bombs every 20 minutes. With such strength, it is no wonder why these natural disasters have such large destructive impacts on the environment. Furthermore, hurricanes are of extreme importance to Florida, since they have historically overwhelmed the state, especially in 1992 with Hurricane Andrew. Since it is certain that hurricanes will hit Florida and equally certain that biological populations (including people) will exist in Florida, there is a need for researching methods to coexist with these monstrous storms. First, to be able to create solutions to hurricane damage, experts must understand the physical manner in which hurricanes actually cause damage. Roger Pielke, in his hurricane book, The Hurricane, identifies four impacts of a hurricane: storm surge, extreme winds, tornadoes, and rainfall. These impacts are not completely separate from each other; they interact, but are different in scope. Storm surge refers to the rapid rise of sea level as a storm approaches a coastline. This is the biggest impact of a hurricane and accounts for 90% of hurricane deaths (Pielke 1990). Storm surges are caused by three factors. First, the overlying atmosphere pressure drops. Second, strong onshore winds cause a piling up of water at the coast. Third, the decreasing sea depth as the ocean approaches the coast causes the surge to get steeper. A storm surge of 15 feet corresponds to a level 5 hurricane, and a surge greater than 5 feet can cause major damage and loss of life. Since surges reduce as they move inland, surges are mostly destructive to beaches. Extreme winds, which carry a lot of kinetic energy, can cause significant structural damage and even endanger life with dangerous wreckage. The damage of winds is relative to the kinetic flow, which is exponential. For example, a wind of 50 ms-1 is four times greater than winds of 25 ms-1. In addition, winds are not restricted to the coasts; extreme winds appear and are destructive far inland. Tornadoes are connected with extreme winds. Although hurricane induced tornadoes are not as strong as the “normal” ones that appear in the Midwest, they still cause a lot of damage and are dangerous to life. Tornadoes are mysterious, but there are theories on their 2005-08-14T01:15:11-04:00 http://75.150.148.189/free-essay/Environmental-Report-Hurricanes-and-their-Tendencies-27624.aspx Essay on Acid Rain Discussion of Acid Rain: How does it occur? "Acid rain" is a broad term used to describe several ways that acids fall out of the atmosphere. A more precise term is acid deposition, which has two parts: wet and dry. Wet deposition refers to acidic rain, fog, and snow. As this acidic water flows over and through the ground, it affects a variety of plants and animals. The strength of the effects depend on many factors, including how acidic the water is, the chemistry and buffering capacity of the soils involved, and the types of fish, trees, and other living things that rely on the water. Dry deposition refers to acidic gases and particles. About half of the acidity in the atmosphere falls back to earth through dry deposition. The wind blows these acidic particles and gases onto buildings, cars, homes, and trees. Dry deposited gases and particles can also be washed from trees and other surfaces by rainstorms. When that happens, the runoff water adds those acids to the acid rain, making the combination more acidic than the falling rain alone. Prevailing winds blow the compounds that cause both wet and dry acid deposition across state and national borders, and sometimes over hundreds of miles. Scientists discovered, and have confirmed, that sulfur dioxide (SO2) and nitrogen oxides (NOx) are the primary causes of acid rain. In the US, About 2/3 of all SO2 and 1/4 of all NOx comes from electric power generation that relies on burning fossil fuels like coal. Acid rain occurs when these gases react in the atmosphere with water, oxygen, and other chemicals to form various acidic compounds. Sunlight increases the rate of most of these reactions. The result is a mild solution of sulfuric acid and nitric acid. How Do We Measure Acid Rain? Acid rain is measured using a scale called "pH." The lower a substance's pH, the more acidic it is. See the pH page for more information. Pure water has a pH of 7.0. Normal rain is slightly acidic because carbon dioxide dissolves into it, so it has a pH of about 5.5. As of the year 2000, the most acidic rain falling in the US has a pH of about 4.3. Acid rain's pH, and the chemicals that cause acid rain, are monitored by two networks, both supported by EPA. The National Atmospheric Deposition Program measures wet deposition, and its Web site features maps of rainfall 2005-08-13T05:49:11-04:00 http://75.150.148.189/free-essay/Essay-on-Acid-Rain-27604.aspx Cloud Research Paper Cloud Research Paper Cloud formations have always been observed by people, many centuries before our time. People were always fond of clouds. They always wondered why some clouds were dark and others were white and fluffy, and why some clouds are so up high and others were so low that they looked reachable by the human hands. The most recent classification of clouds was accomplished by the World Meteorological Organization in 1956. This organization lists 10 basic kinds of clouds that are subdivided into species according to their outer shape and inner structure. In addition, cloud varieties are discussed according to arrangement and transparency. There is a height classification which are called high, middle, and low altitudes. The different kinds of clouds are found in these three divisions according to the clouds' altitude. First, we have the high clouds that range in altitude from 16,500 to 45,000 feet. In this division we have the cirrus, cirrocumulus, and cirrostratus clouds. A cirrus cloud appears in delicate, feather-like bands that are not attached to each other, and is usually white with no shading. Cirrocumulus clouds appear like very small round balls or flakes. The cirrocumulus clouds sometimes form a pattern of a buttermilk sky. The cirrostratus clouds sometimes form tangled webs or thin whitish sheets. A large ring or halo is sometimes seen around the sun or moon when the cirrostratus covers the sky. The middle layer of clouds range in altitude from 6,500 to 23,000 feet. The altocumulus, altostratus, and nimbostratus clouds are found in the middle division. The altocumulus clouds are more rounded and puffier than the cirrocumulus clouds. When people stare at the altocumulus clouds, they usually see a shape of an animal, usually an elephant. Altostratus clouds cover the sky with a grayish veil through which the sun or moon may shine as a spot of pale light. The nimbostratus clouds are the clouds that we can identify the fastest. These are the clouds that ruin our day. Nimbostratus clouds are thick, dark, and shapeless and that brings rain or snow. The last height classification is the low altitude. These low clouds range in altitude from ground level to 6,500 feet. This division includes the last four kinds of clouds, which are: stratocumulus, stratus, cumulus, 2005-06-30T05:14:40-04:00 http://75.150.148.189/free-essay/Cloud-Research-Paper--27206.aspx Facts on Acid Rain! Formation of acid rain. Acid deposition, more commonly known as acid rain, occurs when emissions of sulfur dioxide (SO2) and nitrogen oxides (NOx) react in the atmosphere with water, oxygen, and oxidants to form acidic compounds. This mixture forms a mild solution of sulfuric and nitric acid which then falls to the earth in either wet (rain, snow, sleet or fog) or dry (gas and particles) form. Approximately one-half of the atmosphere's acidity falls back to earth through dry deposition in the form of particles and gases, and are then spread hundreds of miles by winds where they settle on surfaces of buildings, cars, homes, and trees. When acid rain falls, the dry deposited gases and particles are sometimes washed from buildings, trees and other surfaces making the runoff water combine with the acid rain more acidic than the falling acid rain alone. This new combination is referred to as acid deposition. The runoff water is then transported by strong prevailing winds and public sewer systems into lakes and streams. Although some natural sources such as volcanic eruptions, fire and lightening contribute to the emissions of sulfur dioxide and nitrogen oxides in the atmosphere, more than 90% is the result of human activities such as coal burning, smelting of metals such as zinc, nickel and copper, and the burning of oil, coal and gas in power plants and automobiles. When does rain become acidic? Scientists determine whether rain or lake water is acidic by measuring its pH (the measure of acidity or alkalinity of a solution on a scale of 0 to 14). A value of 7 is considered neutral, whereas values less than 7 are acidic and values over 7 are alkaline or basic. A change of one unit on the pH scale represents a factor of ten in acidity; for example, a solution with a pH of five is ten times as acid as one with a pH of six . Normal or clean rainfall--without pollutants--is slightly acidic due to carbon dioxide, a natural gas in the air that dissolves in water to form weak carbonic acid. But rain, snow, or other moisture is not called "acid rain" until it has a pH value below 5.6 . Rainfall in eastern North America is often acidic with a pH of 4 to 5. Why is North America greatly at risk? Acid rain is more common in the Eastern U.S. and Canada than in 2005-06-29T04:25:28-04:00 http://75.150.148.189/free-essay/Facts-on-Acid-Rain--27181.aspx Martian Rocks Commentary on Recent Discoveries from Mars Martian Rocks: Commentary on the Recent Discoveries from Mars H. G. Wells wrote in his book, "War of the Worlds", about Martian invasion toward earth. He mentioned, "No one would have believed, in the last years of the nineteenth century that this world was being watched keenly and closely by intelligences greater than man's and yet as mortal as his own; that as men busied themselves about their various concerns they were scrutinized and studied, perhaps almost as narrowly as man with a microscope might scrutinize the transient creatures that swarm and multiply in a drop of water." Since then it has now been about 100 years Wells based his well-known story of human's first contact with extraterrestrial life. Now, in the 20th century scientists are starting to believe what was once a fictional story by writers now actually could be real, becoming the stuff of science. In 1994 scientists discovered fragments of meteorites which may in fact prove that signs of early life existed on Mars. Many of these meteorites are found in the Antarctica, extremely cold weathers aid in preserving and fossilizing the fallen meteorites for millions of years. In order for scientists to conclude that the meteorites are from Mars and contain signs of fossilized life or traces of it they must provide sufficient evidence to support their theory. Today, a meteorite from Mars is being closely scrutinized by earthly intelligences. The famous meteorite to bare significant signs of life is the Allan Hills 84001 (ALH84001), classified as one of the meteorites thought to come from Mars. Due to the atmospheric data taken by the Viking Lander spacecraft sent to Mars in the 1970s. The data make it possible to know that gases trapped inside the rock is identical to the Martian atmosphere. "It is one of only 12 meteorites identified so far that match the unique Martian chemistry measured by the Viking spacecraft that landed on Mars in 1976" Scientist believed that the ALH84001 blasted off from the surface of Mars about 16 million years ago by a comet or asteroid. The rock orbited in the solar system for a few million years and finally reached Earth about 13, 000 years ago. Investigation into the ALH84001 and the possibilities for containing remains of ancient Martian life was assigned to a team of NASA scientists. Dr. David McKay, Dr. Everett Gibson and Kathie Thomas-Kerpta of Lockhead Martin co-led the team 2005-06-21T22:22:15-04:00 http://75.150.148.189/free-essay/Martian-Rocks-Commentary-on-Recent-Discoveries-from-Mars-27110.aspx How is there Water in the Ground? How do you suppose there is water in the ground? We know that water comes down in dew and in rain (and snow), that it flows along in rivers and streams, and that there is water in lakes, oceans, and any 2004-08-27T06:40:50-04:00 http://75.150.148.189/free-essay/How-is-there-Water-in-the-Ground-25561.aspx The Ocean's Minerals How does the ocean happen to have so many minerals? Let's see if we can duplicate a small part of the answer to this question. Wash some aquarium sand several times, then set the sand out to dry. When it is dry, mix a teaspoonful of table salt with each 4 cups of dry sand. Make a simulated inclined river bed with aluminum foil, and pour the sand and salt mixture into the river bed. Place a bowl at one end to catch the river water. Pour some rain water or distilled water at the top of the river bed. Taste the collected water to see if it contains salt, or set the collected water out to evaporate. You will realize that in a similar way rain water dissolves salts in rocks and soil, carries them from the land 2004-08-27T06:37:33-04:00 http://75.150.148.189/free-essay/The-Ocean-s-Minerals-25560.aspx Background Info on Geology Geology, study of the planet earth, its rocky exterior, its history, and the processes that act upon it. Geology is also referred to as earth science and geoscience. The word geology comes from the Greek geo, “earth,” and logia, “the study of.” Geologists seek to understand how the earth formed and evolved into what it is today, as well as what made the earth capable of supporting life. Geologists study the changes that the earth has undergone as its physical, chemical, and biological systems have interacted during its 4.5 billion year history. Geology is an important way of understanding the world around us, and it enables scientists to predict how our planet will behave. Scientists and others use geology to understand how geological events and earth’s geological history affect people, for example, in terms of living with natural disasters and using the earth’s natural resources. As the human population grows, more and more people live in areas exposed to natural geologic hazards, such as floods, earthquakes, tsunamis, volcanoes, and landslides. Some geologists use their knowledge to try to understand these natural hazards and forecast potential geologic events, such as volcanic eruptions or earthquakes. They study the history of these events as recorded in rocks and try to determine when the next eruption or earthquake will occur. They also study the geologic record of climate change in order to help predict future changes. As human population grows, geologists’ ability to locate fossil and mineral resources, such as oil, coal, iron, and aluminum, becomes more important. Finding and maintaining a clean water supply, and disposing safely of waste products, requires understanding the earth’s systems through which they cycle. The field of geology includes subfields that examine all of the earth's systems, from the deep interior core to the outer atmosphere, including the hydrosphere (the waters of the earth) and the biosphere (the living component of earth). Generally, these subfields are divided into the two major categories of physical and historical geology. Geologists also examine events such as asteroid impacts, mass extinctions, and ice ages. Geologic history shows that the processes that shaped the earth are still acting on it and that change is normal. Many other scientific fields overlap extensively with geology, including oceanography, atmospheric sciences, physics, chemistry, botany, zoology, and microbiology. Geology is also used to study other planets and moons in our solar system. Specialized fields of extraterrestrial geology include lunar geology, the 2004-08-27T06:34:52-04:00 http://75.150.148.189/free-essay/Background-Info-on-Geology--25559.aspx