Kodiak Bear Vs Polar Bear

Kodiak Bear Vs Polar Bear

Although Kodiak and Polar bears are both bear species, they are different in many aspects. The Kodiak bear is a subspecies of the Brown Bear. In fact, it is the largest subspecies of them. Typically, they get much bigger than other Grizzlies, because they have an abundance of Pacific Salmon to consume. They are only found on Kodiak Island, which is off the southern coast of Alaska. They try to avoid any and all contact with humans.

The Polar Bear, on the other hand, is even larger than the Kodiak Bear. They are a direct descendant of the Brown Bear and are now classified as the largest bear on the entire planet. Although they are usually more slender, they are definitely longer and therefore, stand taller. Not only that, but they are now classified as a marine mammal because of the large amount of time that they spend in the water. In fact, they spend months and months of the year out at sea.

Polar bears are social animals. However, whenever they are hungry they will kill almost anything to have something to eat. The most common thing they attack and consume are seals. They have also been known to hunt walrus and beluga whales. They are mostly concentrated within the Arctic circle which encompasses the Arctic Ocean. They can also be found around surrounding land masses.

Kodiak bears are generally solitary animals and are more aggressive than Polar bears are. However, Polar bears are more experienced when it comes to killing extremely large prey. If you were ever to pit these massive species against each other, it could be a toss up as to who would win. They come from very distinct backgrounds, and therefore, they each have different advantages.

If they ever attacked each other, the polar bears would get the first hit. They have longer arms and a longer neck, so it would give them the first benefit. The Kodiaks are likely to avoid fatal injury, though, because they have many layers of fat. The Kodiak would then retaliate. They have a lot of experience in territorial fights with other big bears.

They also have lots of strength and weight to use to their advantage. More than likely, the Kodiak's would charge the Polar Bears and knock them down. It would not be likely that the Polar bear would ever be able to get back up. So, in the end, they would probably lose the fight.

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The Polar Bears

The Polar Bears

The polar bear (Ursus maritimus) is a bear native to the Arctic Ocean and its surrounding seas. The world's largest carnivore found on land, a title it shares with the Kodiak Bear, an adult male weighs around 400–680 kg (880–1,500 lb), while an adult female is about half that size. 

Although it is closely related to the brown bear, it has evolved to occupy a narrow ecological niche, with many body characteristics adapted for cold temperatures, for moving across snow, ice, and open water, and for hunting the seals which make up most of its diet. 

Although most polar bears are born on land, it spends most of its time at sea, hence its name meaning "maritime bear", and can hunt consistently only from sea ice, spending much of the year on the frozen sea.

The polar bear is classified as a vulnerable species, with 5 of the 19 polar bear subpopulations in decline. For decades, unrestricted hunting raised international concern for the future of the species; populations have rebounded after controls and quotas began to take effect. 

For thousands of years, the polar bear has been a key figure in the material, spiritual, and cultural life of Arctic indigenous peoples, and the hunting of polar bears remains important in their cultures.

The IUCN now lists global warming as the most significant threat to the polar bear, primarily because the melting of its sea ice habitat reduces its ability to find sufficient food. The IUCN states, "If climatic trends continue polar bears may become extirpated from most of their range within 100 years." On May 14, 2008, the United States Department of the Interior listed the polar bear as a threatened species under the Endangered Species Act.

source : wikipedia.org via Polar Bears

Polar Bear Cubs - The Start of A Polar Bear's Life

Polar Bear Cubs - The Start of A Polar Bear's Life 

Polar bear cubs start their lives as cute and cuddly youngsters.

This is in stark contrast to the majestic kings of the Arctic they will become if they survive to maturity.

Female polar bears have their first set of cubs between the ages of four and eight (usually at age five or six). Females in the Low Arctic wean their cubs as they approach their second birthday, while those in the High Arctic, where conditions are more a lot more harsh and demanding, care for their cubs an additional year

Polar bear cubs are most often born in pairs, but sometimes the litter contains three cubs and possibly only one cub. They're born between November through January in a den. These snow dens are known as "maternity dens" and are made to protect the newborn cubs from the freezing Arctic temperature extremes.

At birth, the cubs are 30 to 35 centimeters (12 to 14 inches) in length and weigh a little more than half a kilogram (about a pound) . Having no senses, during their first few vulnerable weeks of life, they nurse most of the time and stay as close as possible to their mother to keep themselves warm. The female has special crevices within which the cubs can get the warmth they need to survive.

Polar bear cubs are born small and helpless, with their eyes closed and their fur is very fine at birth, making the cubs look hairless. They get their first glimpses of their mothers after they open their eyes sometime during the first month.

The cubs grow very quickly while they're in the den, thanks to the calories in their mother's rich milk, which has a fat content of roughly 31% . Cubs often lie on there mothers belly to nurse while their mother sits back and puts her head back and seems to slightly move back and forth as if to rock the cubs. The cubs begin walking inside the den at roughly two months. During this time, the cubs still spend about 85% of their time in the den, sleeping there at night.

When she finally emerges with her cubs, most often in late March or April, she leads them to the sea ice so she can break her long fast by hunting seals. Cubs begin eating solid food at this time which is at approximately three to four months of age.

The cubs usually stay with their mother until they're 2 1/2 years old, although some bears in the Hudson Bay area wean their young at age 1 1/2 . When the cubs reach a point where they have suitable strength and coordination, and when they are able to walk well and respond to their mother's motion and sound commands such as stay or come, they are ready to leave their mother and the den.

During the time that the cubs are with their mother, they must learn how to hunt and survive in one of the Earth's harshest environments by watching their mother. A mother bear's success at hunting seals directly influences their well-being and determines whether or not the cubs will live or die once they are on their own. A mother will sometimes carry her cubs on her back through areas of deep snow or water if conditions are too hazardous for the youngster.

Once the cubs are weaned, either the mother bear or the male chases the cubs away so that they can begin life on their own.

Polar Bear Cubs and Environmental Issues

As you can see, Polar bear cubs are very vulnerable during their first few months. This period is the time during which most of the deaths from global warming and pollution take place.

Mother bears are feeding on polluted fish and seals. The pollution is stored in their massive body fat and when they have their offspring, they pass the pollution on to the young via there high-fat mother's milk. Often their cub's immune systems are too weak to fend off the toxins and the resulting complications, so they die.

Global climate change is shortening the time that bears have to breed and this means that they put off having their children until too far into the season. So, fewer bears are being born.

This double whammy is causing Polar bear populations to decrease dramatically.

One study estimated that only 43 percent of polar bear cubs in the southern Beaufort Sea survived their first year during the year 2000, compared to a 65 percent survival rate in the late 1980s and early 1990s.

Clearly, something must be done to maintain polar bear reproduction at a rate that ensures the survival of the species.

Article Source: EzineArticles.com via Polar Bears

How Do You Define Happiness

How Do You Define Happiness?

By: Doug Hart

Today’s topic is one that has been pondered for centuries, the true meaning of happiness. Aristotle said “Happiness is the meaning and the purpose of life, the whole aim and end of human existence”. Do you agree?

Ok, in the big picture of things nearly everything we do on a daily basis is in one way or another related to obtaining happiness, or at the very least avoiding pain (some people work to not have their car repossessed!).

But we all know there are different levels of happiness, many indeed. Some people may be happy because they were raised to be that way, having parents that always saw the best of any situation. Unfortunately, some people are miserable not matter how circumstances are treating them in life. Why?

I think there are several reasons for this, but mostly we are as happy as we make up our minds to be (Abraham Lincoln said that first, not me!) So why don’t we all just make up our minds to be happy? Great question – I’ll try to answer it.

It starts with our “version” of reality, our perceptions of what reality is to us as an individual. Now, depending on your circumstances growing up, you literally had millions of different events that influenced your reality, so every person has a different version.

The way you experience a trip to the beach may be totally different than my way, due to some incident that occurred to you as a child. Say you nearly were eaten by a shark once – that probably gave you “bad taste” in your mouth when trips to the beach are mentioned.

See what I mean? Yes! But I’m an adult now, I can believe anything I want to believe! True, but think about some of the things you believe in. What do you believe would make you happy? Do you have all of those things? If not, then why not?

Ah-hah! That’s what I thought – very few people actually have what they feel would make them happy! Do you even know, in great detail, what would make you happy? And don’t say a million dollars, because that by itself rarely makes people happy.

I know, at least you could try, right? Ok, make a list!Find out what you believe in your heart would make you happy…Ok, how about peace of mind? A totally perfect relationship with your spouse? A large home in the mountains with a beautiful view?

How about a career that really makes you want to go to work every day? What would it take to have all of the things on your list, if you don’t already have them?

You probably need to change yourself. But what if you have all of those things and more, but still aren’t happy? I believe many people achieve all they set out to achieve, yet true happiness still eludes them. First, find your passion in life.

Chances are if you haven’t found your true passion in life, then you aren’t happy. Or maybe you are “conditionally happy”, in other words if all is going well then your happy for the moment.

But I believe to be truly happy on very deep level on a daily basis, a happiness that is unbending and unwavering not matter what the circumstances, you must first find your passion in life. So what are you waiting for?

source : articledashboard.com via Happiness

Get Soft and Silky Hair Naturally

 

Get Soft and Silky Hair Naturally

By John Goh

Polynesian women are famed for their beautiful, soft and silky hair. Their hair is always in good condition despite the hot blistering sun of the tropics. The blowing of the ocean breeze every day does nothing to ruin or damage their hair. What is their secret? The secret is that they use coconut oil as a hair conditioner.

Coconut oil does a lot for hair. It makes hair soft and silky, easy to brush through and brings its condition back to touchable. It even smells nice and is great for a pampering session before a good night out. The small molecular structure of coconut oil allows for easy absorption, giving hair a smooth and soft texture.

Coconut oil is easy to use on hair. Put it on the hair, rub it in, relax for a minute or two, and wash out. The procedure is as simple as that. With perfect results you can feel the effect even before the hair dries.

To get better results, some people apply a couple of teaspoons of warm coconut oil at night and wash out the oil in the morning. To warm the oil, you can place the bottle in warm water. 

If you find that too troublesome, put the oil on and cover your head with a shower cap for about an hour. You can take a long relaxing bath in the meantime. Wash out the oil from your hair after that. Repeat this procedure every few days for luxurious hair.

Beauticians who are familiar with coconut oil swear by it. They claim that using coconut oil as a hair conditioner can be just as effective as an expensive hair salon treatment. It is much cheaper too and can be applied by yourself. Coconut oil softens the hair and conditions the scalp.

Another benefit of using coconut oil as a pre-wash conditioner is that it can rid a person of dandruff better than a medicated shampoo. In some cases, a single application of coconut oil on hair eliminates all dandruff problems. Coconut oil also does not have the harsh chemicals used in many medicated shampoos.

source : ezinearticles.com via Beauty Tips

How To Take Care Of Oily Hair

How To Take Care Of Oily Hair

Hair is probably the most beautiful feature that can make you look simply gorgeous. The strong and shiny hair, along with a nice hair style, can enhance your beauty and gives you a more appealing personality. For this it’s vital that you use the best hair products. For looking good, there should not be any kind of compromise in the selection of hair products. To look stunning get the best hair products and enhances the quality of hair.

Many hair shampoos promise results in help with oily scalps but few offer results. Oily scalp shampoos are guaranteed to help control excess sebum and greasiness offering shiny, clean, grease-free hair. Oily scalp shampoos are designed to be used between three to seven times per week and not only work well, but smell great. The hair shampoos can be used in addition to your favorite shampoo or as a stand-alone product. The choice is yours.

Oily scalp shampoo usually works on the glands that produce the oil. They may use nutrients like zinc to help even out the amount of oil you are producing. Oily scalp shampoo can also help break up the oil that is on the shaft of the hairs themselves and are often very effective.

There are a few differences between an oily scalp shampoo and one meant to help other hair problems. Oily scalp shampoos are designed to be less heavy in conditioners than other shampoos. If there is a higher percentage of detergent in the product you are using, it can be quite effective as an oily scalp shampoo.

Massage your hair and scalp while shampooing. With the finger balls massage the scalp gently. It is called ‘spider doing push-ups’ fashion. It is vital and critical in your hair care routine. It helps to loosening the sebaceous glands of your hair scalp and secrets the sebum, which is a natural form of essential fatty acids. It feels good and soothing and condition your hair and tone up your hair. There are lots of ways of massaging for different types of hair.

Products for natural hair care help in substantial growth of hair as they contain vitamins and useful minerals that facilitate in normal hair growth. The most widely used vitamins for natural hair care products are B12 and vitamin C. These are the tow vitamins that are used in almost every natural hair care product. Vitamin E is also used quite commonly.

The treatment which you use for oily hair will vary depending upon the severity of it. There are hair products especially designed for oily hair which are not as moisturized as some other products. You should also avoid over brushing your hair, and cleaning your hair brush every now and again is a great idea.

Brushing too often is also not a good idea as, although when you have healthy hair, brushing often makes it look nice and healthy, it does stimulate the oil glands. When oily hair is already producing too much oil, the last thing you want to do is stimulate the glands even more! So always avoid brushing too much.

Some problems which can be caused through severe oily hair include the hair falling out. This is particularly true in men over the age of thirty five. Oily hair can also lead to dandruff which again can cause all kinds of other problems.

By: Beauty and Health care

Article Source articledashboard.com via Beauty Tips

Big Beautiful Eyes With Make Up

Big Beautiful Eyes With Make Up

Eyes always articulate the truth which means even if you want to lie, your eyes, which happen to be the windows of your soul, will hardly allow you to do the misdeed. That is exactly why many a time man's eyes are referred to as god's own reflectors of the truth.

We often look into someone's eyes and reckon we are in love with him or her. It is right that such emotions which a man can sometimes not speak with his mouth are reflected with all the certainty with the help of his eyes. You can hardly keep anything from the people around you for your eyes will speak everything that you always wanted them to know. Eyes also aid us with the perfect ability to gauge different personalities which is also one of the major positives of the same.

Apart from the aforementioned and as far as women are concerned, there could be nothing better than helping them make their eyes look bigger and better with make-up which is in vogue nowadays. Every one wants to look beautiful which is why people all over the world have begun to depend a great deal up on the cosmetic industry, changing their external appearance and overall personalities too in the bargain.

They do not mind spending tons and tons of money in a bid to change the way they look at the end of the day for that is what they want. Especially since the beginning of the television industry every other woman wants to have eyes like the actresses on the big screen which is why they are splurging like maniacs each time they tend to visit the market place at their end.

But it definitely does your self-esteem a whole lot of good when you end up looking good. Eye make up is one of the most important aspects of make-up these days. The whole idea is to accentuate the eye area and keep the rest of the face nude which is why your eyes look bigger and better most of the time.

You could simply try the Smokey trick to give them the boost that they always required in a bid to look big and beautiful. For that all you need is a kohl pencil and some black eye shadow. Start with cleaning your face which also includes your eye area. Then dab dry after which you should go ahead and apply the shade of foundation that suits your skin and color both so that you don't look too made up at the end of the exercise.

Now, take the black eye shadow and apply is slowly on your upper eye lid merging it with your skin. Once you are done with applying the black eye shadow, curl your lashes and layer them up with mascara. This way they will look nice and long giving you a sensuous look that you probably always wanted.

Use the white pencil to outline the inner area of the lower lid so as to help enhance the eye area making your eyes look bigger in the deal. And at the end, just apply some kohl outside the lower lid or on the circumference of your lower lid so as to help your eyes look really hot and sultry, just as you wanted them to be.

Making your eyes look bigger is hardly a problem for all you need to have is a white liner pencil that will help enhance the eye area of your eyes making them look bigger too in the whole work out. After all, beauty lies in the eyes of the beholder and if your eyes are not big enough then how would they help you look beautiful?

Article Source: EzineArticles.com via Beauty Tips

A Few Make Up Techniques to Develop Natural Beauty

A Few Make Up Techniques to Develop Natural Beauty

By James Redwood

Start your make up with a clean face. In order to get great results you have to concentrate on your face while cleaning.

Problems may occur if you start make over on an oily face and it doesn't adhere nicely. So whenever you are ready to give some make over on your face, you have to start off with clean and fresh face by using a good facial cleanser.

Focus on good looking Part: This may seem like common sense but it is a must and to focus on your sexiest feature.

For example if you have broad eyes with long thin lashes, then try to add more flavor to your smoky eyes to get sexy look. And another example is your lips.

Almost they make temptation, if you keep your lips toned down. In other words you have to highlight the main focal point with other supporting features. Make sense? But finally, what you end up is to make yourself looking catchy, noticeable and of course sexy.

Less is best! Yes, this is right. You have to keep yourself fairly natural. Your particular make up style makes you to feel comfortable in any occasion.

Don't do any mistake like irregular over make up that 90% women are doing in this world. Watch the current trending cosmetics and choose the best color match that fits you. In other hand you can also get fair in natural methods by using mild soaps and minerals.

Try Mineral Make up Naturally:

Of course, some people have sensitive skin and have to be careful about using make up. If you are one among the crowd then I highly suggest you grab the advantage of mineral make up that is available at a low cost.

Because it is highly jam packed with natural organic ingredients and can find it in all local departmental stores, as well as online counters. But before stepping in, you can also ask for complementary samples from the vendors and this enables you to find right shade for your skin tone respectively.

source EzineArticles.com via Beauty Tips

Advantages Of Teaching With The Digital Microscope

Advantages Of Teaching With The Digital Microscope

Technology has been extensively used in the field of scientific research and much debate has been on for implementing it in the education system. The argument sighted in this regard is that introducing new technology at an early age would help students better understand the different aspect of subjects such as biology, chemistry, earth science and environmental science. Introduction of technology such as the digital microscope is now seen as an integral part of teaching rather than an add-on to the instructional methods already in place.

As stated by Kara Dawson,“We refer to our technology integration as a continuing evolution because each semester more faculty members are incorporating technology in their courses and more faculty members are experimenting with new forms of technology integration.” (Dawson, K. (2004). Illustrations of technology integration in the Unified Elementary Proteach program. Contemporary Issues in Technology and Teacher Education, 4(1), 64-72).

Use of the computer microscope such as the SmartScope has changed the way both teachers and students view seemingly difficult subjects such as science. Educators especially see the digital microscope as a potent, hands-on tool for the students to handle with minimal supervision. Introducing such a technology at an early age also ensures that students who desire to take up teaching as a profession in future also learn the advantages of using such instruments while teaching.

The digital microscope allows a more inclusive and interactive classroom technology rather than the teacher getting entangled in teaching how to operate an instrument. The intuitive design ensures that even students from elementary school are able to operate with ease.

Different aspects being taught in the subjects such as biology can be easily conveyed using a practical approach with the digital microscope. For instance, students can be instructed to make a continuous video or a time lapse video to learn different stages of plant growth.

For this purpose they can plant a seed and keep it under observation using the video feature of the digital microscope. Once the germination period is over, they can wait till the first leaves start appearing and again take a video till the leaves come out completely. These two videos can then be viewed together, showing stages of plant growth in one continuous stream.

The digital microscope is a useful educational tool, enabling the teachers to show the finer details of the object under study. For instance, while teaching cell structure, students can actually view a cell through the digital microscope. The instrument offers high resolution imaging of up to 1280 to 1024 and magnification ranging from 10x to 200x.

Apart from this, there are 6 LED lights enable clear view of the cell being studied. The image taken through the digital microscope can be easily viewed on a computer monitor or projected on a screen, allowing the entire class to view and discuss different parts of the cell.

Implementation of technology in the field of education has given the teachers an opportunity to enhance their teaching skills. They can now concentrate on teaching the finer aspects of the object under investigation. This also allows them to be more interactive with the class, enabling in-depth discussion of the subject.

By: David Walling

source articledashboard.com via Useful Article

Signs Of Skin Cancer

Signs Of Skin Cancer

A survey of the American Cancer Society says that three out of every four American families have at least one family member diagnosed with cancer. A cancer diagnosis affects not only the cancer patient, but also their family, friends & co-workers. Any kind of relationship with a cancer patient should provide them with some amount of support, proving you to be an understanding person, who is able to appreciate their situation.

A cancer diagnosis can be a real crisis; everything seems to going in a haphazard way. There is also a need to provide a superficial feeling of ‘the helping hand’, as you struggle to comprehend your own feelings. Escorting a cancer patient to navigate the maze of details like finding an oncologist, understanding their treatment options, furnishing health updates etc are a few of the important functions that you ought to perform.

Below are some tips to help you cope when someone you love is diagnosed with cancer:

• One way to keep the mind free from being vulnerable and besieged is to offer support. Taking things in a pragmatic way such as driving them to treatments or doctors’ appointments, running errands, baby-sitting, doing household work etc helps a lot. Ask them what they are most concerned about not being able to do.

• Some questions posed at the doctor if and when you accompany your loved one to their appointments will definitely not go amiss.

• Don’t get startled if any change occurs in their behavior and mood.

Cancer medications, sickness, and stress can cause your loved one to become arrogant or morose. For example: - Generally this kind of behavior is seen in skin cancer patients. So you need to maintain some amount of tolerance while dealing with a cancer patient.

• Keep them as active and independent as possible, which will help your loved one to regain a sense of confidence and control over their life.

• Be practical and realistic in terms of daily requirements. Get enough sleep, eat properly, and take some time off for yourself, because you will not be able to work in times of help or need if you are exhausted and sick.

Take care of yourself and your needs; it will be easier to meet the needs of your loved one.

• Ask other family members and friends to help. They will appreciate the opportunity to do so.

• Maintain a positive attitude.

• Accept that there are things that are beyond your control.

• Be assertive instead of aggressive. Assert your feelings, opinions, or beliefs instead of fuming, being belligerent or passive.

• Fight stress, learn to relax. Exercise regularly.

• Avoid confrontation; feel at ease with their answers.

Join a support group for friends and families of cancer patients.

Remember that you are not alone if someone you love is diagnosed with cancer. You are likely to experience a conflicting range of emotions, including disbelief, anger, relief, worry and even guilt. Fears of mortality, puzzling family roles, having your own needs met, and uncertainty about the future can surface when your loved one is diagnosed with cancer. These are customary feelings which may prove to be a problem. It will hence be beneficial to talk to others who are undergoing the same problems. These were some common points led down by American cancer society.

source articledashboard.com via Cancer Form

Mesothelioma Diagnosis Is Very Systematic

Mesothelioma Diagnosis Is Very Systematic

Mesothelioma is a very serious form of cancer that occurs on the mesothelium (a membrane that covers and protects most of the internal organs of the body.).

This rare cancer has only one known cause called asbestos which is a naturally occurring mineral. People, who become victims, are said to have frequently inhaled this mineral's dust either in the mines, factories or in construction works.

This disease might take years to materialize but when it does, patients will show different symptoms depending on the type and stage of infection.

Mesothelioma diagnosis is confirmed to be complicated by the doctors, because the symptoms might resemble those of similar conditions such as asbestosis.

When a patient consults the doctor for the first time, both of them have got no surety that the disease is mesothelioma. The diagnosis therefore starts:

Review of the patient's medical history

After the doctor listens to the number of symptoms given by the patient whom he does not know to start with, it becomes essential for him to inquire about his medical history.

He may ask question that tend to probe the patient's exposure to asbestos so he form the bases for diagnosis. If for sure, he worked in a plant that manufacture's asbestos products or is still working in a place that puts him in such a risk, then mesothelioma becomes a potential suspect.

Physical examination

A physical examination will enable the doctor to start the proper diagnosis process where a number of things will be done.

X- ray- the X-ray reveal pleural thickening usually seen after the asbestos exposure and raises more suspicion of mesothelioma.

CT or CAT scan

This represent a chain of comprehensive pictures of areas inside the body developed by a computer linked to an X-ray machine.

In an MRI, a powerful magnet linked to a computer is used to make thorough pictures of areas inside the body. These pictures are viewed on a monitor and can also be printed. These should show if there are malignant cells or not.

Biopsy

A biopsy is required to confirm a diagnosis that the doctor performs on mesothelioma. The surgeon or a medical oncologist, who specializes on cancer diagnosis and treatment, removes a sample of tissue for examination under the power of microscope by a pathologist. This can be done in diverse ways depending on where this cancer is suspected to be.

Thoracoscopy

Here the doctor uses a tool called a thorascope after making a small cut on the victim's chest, where it is inserted between the two ribs to obtain the tissue material.

Peritoneoscopy

If the doctor want to obtain tissue sample from the abdominal cavity, he performs this procedure using a peritoneoscope. This is inserted through a small hole that a doctor makes on the abdomen and is able to explore and grab some tissue samples.

If these procedures do not give up enough tissue, more widespread diagnostic surgery may be compulsory. If the diagnosis is mesothelioma however, the doctor will then want to find out how far the cancer has gone. 

To be able to do this (staging), more special test will be performed.

Localized

Mesothelioma that will only be found on the membrane surface where it originated.

Classified- this is mesothelioma cancer that has spread further than the original membrane surface to the rest of the body parts like the lymph nodes, chest wall, lungs and abdominal organs.

source : articledashboard.com via  Mesothelioma Cancer 

Garden Landscape Design - 7 Tips to Design a Beautiful Garden Landscape

Garden Landscape Design - 7 Tips to Design a Beautiful Garden Landscape 

The first question you need to ask yourself is 'Does the design on paper blend in with the house?'. This means that the texture, color and shape should reflect unity and uniformity. Having all kinds of shapes and colors no matter how expensive is a big no

When designing a garden landscaping plan remember to incorporate the basic art of simplicity. Just use a few colors for your garden. Having plants of different colors will just produce a 'clown' garden

Incorporating the art of balance is a big step towards a beautiful garden. Balance can be symmetrical meaning that you get to have a garden that has equally spaced matching plant heights and bed shapes. The second form is the asymmetrical design that is a bit complex. In simple terms, it means you have to be unbalanced while still maintaining some balance.

Color is another vital key to having an exquisite garden. It is important for you to study the basic colors and understand the kind of effect the chosen colors are bound to bring to your garden.

Garden Landscape 

Consider the use of natural transition. This would avoid sudden changes on the garden design. For instance, you can have a step effect on the flowers where some are taller than others, have the medium sizes and finally the bedding flowers.

One of the most overlooked factors is the issue of repetition. This is a close relative to balance and unity. One cannot experience unity without having repetitive designs. However, this has a limitation for too much repetition will cause monotony and boredom.

Always remember that the garden reflects your personality. It does not make sense to have a garden that you will not enjoy spending time in at the end of a long day's work.

Overall, it is important that you have a budget before you start your garden landscaping. Keep in mind that some forms of landscaping methods might be very expensive as compared to others. However, with the help of a good plan, then you will be able to have a good garden landscape within no time. 

Always learn from other people's experiences, this will help you minimize on the some of the costly mistakes. You can easily find advice on the Internet. Visit some of the forums, blogs, and websites that discuss landscaping and you will get good knowledge and experience that will help you in your quest to have a beautiful garden landscape.

Article Source: http://EzineArticles.com/?expert=Antony_N_Maina

Earthquake Information

Earthquake Information

From Wikipedia, the free encyclopedia

An earthquake (also known as a quake, tremor or temblor) is the result of a sudden release of energy in the Earth's crust that creates seismic waves. The seismicity, seismism or seismic activity of an area refers to the frequency, type and size of earthquakes experienced over a period of time. Earthquakes are measured using observations from seismometers. The moment magnitude is the most common scale on which earthquakes larger than approximately 5 are reported for the entire globe. The more numerous earthquakes smaller than magnitude 5 reported by national seismological observatories are measured mostly on the local magnitude scale, also referred to as the Richter scale.

These two scales are numerically similar over their range of validity. Magnitude 3 or lower earthquakes are mostly almost imperceptible and magnitude 7 and over potentially cause serious damage over large areas, depending on their depth. The largest earthquakes in historic times have been of magnitude slightly over 9, although there is no limit to the possible magnitude. The most recent large earthquake of magnitude 9.0 or larger was a 9.0 magnitude earthquake in Japan in 2011 (as of March 2011), and it was the largest Japanese earthquake since records began. Intensity of shaking is measured on the modified Mercalli scale. The shallower an earthquake, the more damage to structures it causes, all else being equal.[1]

At the Earth's surface, earthquakes manifest themselves by shaking and sometimes displacement of the ground. When the epicenter of a large earthquake is located offshore, the seabed may be displaced sufficiently to cause a tsunami. Earthquakes can also trigger landslides, and occasionally volcanic activity.

In its most general sense, the word earthquake is used to describe any seismic event — whether natural or caused by humans — that generates seismic waves. Earthquakes are caused mostly by rupture of geological faults, but also by other events such as volcanic activity, landslides, mine blasts, and nuclear tests. An earthquake's point of initial rupture is called its focus or hypocenter. The epicenter is the point at ground level directly above the hypocenter.

Naturally occurring earthquakes

Tectonic earthquakes occur anywhere in the earth where there is sufficient stored elastic strain energy to drive fracture propagation along a fault plane. The sides of a fault move past each other smoothly and aseismically only if there are no irregularities or asperities along the fault surface that increase the frictional resistance. Most fault surfaces do have such asperities and this leads to a form of stick-slip behaviour. Once the fault has locked, continued relative motion between the plates leads to increasing stress and therefore, stored strain energy in the volume around the fault surface. This continues until the stress has risen sufficiently to break through the asperity, suddenly allowing sliding over the locked portion of the fault, releasing the stored energy.

This energy is released as a combination of radiated elastic strain seismic waves, frictional heating of the fault surface, and cracking of the rock, thus causing an earthquake. This process of gradual build-up of strain and stress punctuated by occasional sudden earthquake failure is referred to as the elastic-rebound theory. It is estimated that only 10 percent or less of an earthquake's total energy is radiated as seismic energy. Most of the earthquake's energy is used to power the earthquake fracture growth or is converted into heat generated by friction. Therefore, earthquakes lower the Earth's available elastic potential energy and raise its temperature, though these changes are negligible compared to the conductive and convective flow of heat out from the Earth's deep interior.[2]

Earthquake fault types

There are three main types of fault that may cause an earthquake: normal, reverse (thrust) and strike-slip. Normal and reverse faulting are examples of dip-slip, where the displacement along the fault is in the direction of dip and movement on them involves a vertical component. Normal faults occur mainly in areas where the crust is being extended such as a divergent boundary. Reverse faults occur in areas where the crust is being shortened such as at a convergent boundary. Strike-slip faults are steep structures where the two sides of the fault slip horizontally past each other; transform boundaries are a particular type of strike-slip fault. Many earthquakes are caused by movement on faults that have components of both dip-slip and strike-slip; this is known as oblique slip.

Reverse faults, particularly those along convergent plate boundaries are associated with the most powerful earthquakes, including almost all of those of magnitude 8 or more. Strike-slip faults, particularly continental transforms can produce major earthquakes up to about magnitude 8. Earthquakes associated with normal faults are generally less than magnitude 7.

This is so because the energy released in an earthquake, and thus its magnitude, is proportional to the area of the fault that ruptures[3] and the stress drop. Therefore, the longer the length and the wider the width of the faulted area, the larger the resulting magnitude. The topmost, brittle part of the Earth’s crust, and the cool slabs of the tectonic plates that are descending down into the hot mantle, are the only parts of our planet which can store elastic energy and release it in fault ruptures.

Rocks hotter than about 300 degrees Celsius flow in response to stress; they do not rupture in earthquakes.[4][5] The maximum observed lengths of ruptures and mapped faults, which may break in one go are approximately 1000 km. Examples are the earthquakes in Chile, 1960; Alaska, 1957; Sumatra, 2004, all in subduction zones. The longest earthquake ruptures on strike-slip faults, like the San Andreas Fault (1857, 1906), the North Anatolian Fault in Turkey (1939) and the Denali Fault in Alaska (2002), are about half to one third as long as the lengths along subducting plate margins, and those along normal faults are even shorter.

The most important parameter controlling the maximum earthquake magnitude on a fault is however not the maximum available length, but the available width because the latter varies by a factor of 20. Along converging plate margins, the dip angle of the rupture plane is very shallow, typically about 10 degrees.[6] Thus the width of the plane within the top brittle crust of the Earth can become 50 to 100 km (Tohoku, 2011; Alaska, 1964), making the most powerful earthquakes possible.

Strike-slip faults tend to be oriented near vertically, resulting in an approximate width of 10 km within the brittle crust,[7] thus earthquakes with magnitudes much larger than 8 are not possible. Maximum magnitudes along many normal faults are even more limited because many of them are located along spreading centers, as in Iceland, where the thickness of the brittle layer is only about 6 km.[8][9]

In addition, there exists a hierarchy of stress level in the three fault types. Thrust faults are generated by the highest, strike slip by intermediate, and normal faults by the lowest stress levels.[10] This can easily be understood by considering the direction of the greatest principal stress, the direction of the force that ‘pushes’ the rock mass during the faulting. In the case of normal faults, the rock mass is pushed down in a vertical direction, thus the pushing force (greatest principal stress) equals the weight of the rock mass itself. In the case of thrusting, the rock mass ‘escapes’ in the direction of the least principal stress, namely upward, lifting the rock mass up, thus the overburden equals the least principal stress. Strike-slip faulting is intermediate between the other two types described above. This difference in stress regime in the three faulting environments can contribute to differences in stress drop during faulting, which contributes to differences in the radiated energy, regardless of fault dimensions.

Earthquakes away from plate boundaries

Where plate boundaries occur within continental lithosphere, deformation is spread out over a much larger area than the plate boundary itself. In the case of the San Andreas fault continental transform, many earthquakes occur away from the plate boundary and are related to strains developed within the broader zone of deformation caused by major irregularities in the fault trace (e.g., the "Big bend" region).

The Northridge earthquake was associated with movement on a blind thrust within such a zone. Another example is the strongly oblique convergent plate boundary between the Arabian and Eurasian plates where it runs through the northwestern part of the Zagros mountains. The deformation associated with this plate boundary is partitioned into nearly pure thrust sense movements perpendicular to the boundary over a wide zone to the southwest and nearly pure strike-slip motion along the Main Recent Fault close to the actual plate boundary itself. This is demonstrated by earthquake focal mechanisms.[11]

All tectonic plates have internal stress fields caused by their interactions with neighbouring plates and sedimentary loading or unloading (e.g. deglaciation[12]). These stresses may be sufficient to cause failure along existing fault planes, giving rise to intraplate earthquakes.[13]

Shallow-focus and deep-focus earthquakes

The majority of tectonic earthquakes originate at the ring of fire in depths not exceeding tens of kilometers. Earthquakes occurring at a depth of less than 70 km are classified as 'shallow-focus' earthquakes, while those with a focal-depth between 70 and 300 km are commonly termed 'mid-focus' or 'intermediate-depth' earthquakes. In subduction zones, where older and colder oceanic crust descends beneath another tectonic plate, deep-focus earthquakes may occur at much greater depths (ranging from 300 up to 700 kilometers).[14] These seismically active areas of subduction are known as Wadati-Benioff zones. Deep-focus earthquakes occur at a depth where the subducted lithosphere should no longer be brittle, due to the high temperature and pressure. A possible mechanism for the generation of deep-focus earthquakes is faulting caused by olivine undergoing a phase transition into a spinel structure.[15]

Earthquakes and volcanic activity

Earthquakes often occur in volcanic regions and are caused there, both by tectonic faults and the movement of magma in volcanoes. Such earthquakes can serve as an early warning of volcanic eruptions, as during the Mount St. Helens eruption of 1980.[16] Earthquake swarms can serve as markers for the location of the flowing magma throughout the volcanoes. These swarms can be recorded by seismometers and tiltmeters (a device that measures ground slope) and used as sensors to predict imminent or upcoming eruptions.[17]

Rupture dynamics

A tectonic earthquake begins by an initial rupture at a point on the fault surface, a process known as nucleation. The scale of the nucleation zone is uncertain, with some evidence, such as the rupture dimensions of the smallest earthquakes, suggesting that it is smaller than 100 m while other evidence, such as a slow component revealed by low-frequency spectra of some earthquakes, suggest that it is larger. The possibility that the nucleation involves some sort of preparation process is supported by the observation that about 40% of earthquakes are preceded by foreshocks. Once the rupture has initiated it begins to propagate along the fault surface. The mechanics of this process are poorly understood, partly because it is difficult to recreate the high sliding velocities in a laboratory. Also the effects of strong ground motion make it very difficult to record information close to a nucleation zone.[18]

Rupture propagation is generally modeled using a fracture mechanics approach, likening the rupture to a propagating mixed mode shear crack. The rupture velocity is a function of the fracture energy in the volume around the crack tip, increasing with decreasing fracture energy. The velocity of rupture propagation is orders of magnitude faster than the displacement velocity across the fault. Earthquake ruptures typically propagate at velocities that are in the range 70–90% of the S-wave velocity and this is independent of earthquake size. A small subset of earthquake ruptures appear to have propagated at speeds greater than the S-wave velocity. These supershear earthquakes have all been observed during large strike-slip events. The unusually wide zone of coseismic damage caused by the 2001 Kunlun earthquake has been attributed to the effects of the sonic boom developed in such earthquakes. Some earthquake ruptures travel at unusually low velocities and are referred to as slow earthquakes. A particularly dangerous form of slow earthquake is the tsunami earthquake, observed where the relatively low felt intensities, caused by the slow propagation speed of some great earthquakes, fail to alert the population of the neighbouring coast, as in the 1896 Meiji-Sanriku earthquake.[18]

Tidal forces

Research work has shown a robust correlation between small tidally induced forces and non-volcanic tremor activity.[19][20][21][22]

Earthquake clusters

Most earthquakes form part of a sequence, related to each other in terms of location and time.[23] Most earthquake clusters consist of small tremors that cause little to no damage, but there is a theory that earthquakes can recur in a regular pattern.[24]

Aftershocks

An aftershock is an earthquake that occurs after a previous earthquake, the mainshock. An aftershock is in the same region of the main shock but always of a smaller magnitude. If an aftershock is larger than the main shock, the aftershock is redesignated as the main shock and the original main shock is redesignated as a foreshock. Aftershocks are formed as the crust around the displaced fault plane adjusts to the effects of the main shock.[23]

Earthquake swarms

Earthquake swarms are sequences of earthquakes striking in a specific area within a short period of time. They are different from earthquakes followed by a series of aftershocks by the fact that no single earthquake in the sequence is obviously the main shock, therefore none have notable higher magnitudes than the other. An example of an earthquake swarm is the 2004 activity at Yellowstone National Park.[25]

Earthquake storms

Sometimes a series of earthquakes occur in a sort of earthquake storm, where the earthquakes strike a fault in clusters, each triggered by the shaking or stress redistribution of the previous earthquakes. Similar to aftershocks but on adjacent segments of fault, these storms occur over the course of years, and with some of the later earthquakes as damaging as the early ones. Such a pattern was observed in the sequence of about a dozen earthquakes that struck the North Anatolian Fault in Turkey in the 20th century and has been inferred for older anomalous clusters of large earthquakes in the Middle East.[26][27]

Size and frequency of occurrence

It is estimated that around 500,000 earthquakes occur each year, detectable with current instrumentation. About 100,000 of these can be felt.[28][29] Minor earthquakes occur nearly constantly around the world in places like California and Alaska in the U.S., as well as in Mexico, Guatemala, Chile, Peru, Indonesia, Iran, Pakistan, the Azores in Portugal, Turkey, New Zealand, Greece, Italy, and Japan, but earthquakes can occur almost anywhere, including New York City, London, and Australia.[30] Larger earthquakes occur less frequently, the relationship being exponential; for example, roughly ten times as many earthquakes larger than magnitude 4 occur in a particular time period than earthquakes larger than magnitude 5. In the (low seismicity) United Kingdom, for example, it has been calculated that the average recurrences are: an earthquake of 3.7–4.6 every year, an earthquake of 4.7–5.5 every 10 years, and an earthquake of 5.6 or larger every 100 years.[31] This is an example of the Gutenberg-Richter law.

The number of seismic stations has increased from about 350 in 1931 to many thousands today. As a result, many more earthquakes are reported than in the past, but this is because of the vast improvement in instrumentation, rather than an increase in the number of earthquakes. The United States Geological Survey estimates that, since 1900, there have been an average of 18 major earthquakes (magnitude 7.0–7.9) and one great earthquake (magnitude 8.0 or greater) per year, and that this average has been relatively stable.[33] In recent years, the number of major earthquakes per year has decreased, though this is probably a statistical fluctuation rather than a systematic trend.[citation needed] More detailed statistics on the size and frequency of earthquakes is available from the United States Geological Survey (USGS).[34] A recent increase in the number of major earthquakes has been noted, which could be explained by a cyclical pattern of periods of intense tectonic activity, interspersed with longer periods of low-intensity. However, accurate recordings of earthquakes only began in the early 1900s, so it is too early to categorically state that this is the case.[35]

Most of the world's earthquakes (90%, and 81% of the largest) take place in the 40,000 km long, horseshoe-shaped zone called the circum-Pacific seismic belt, known as the Pacific Ring of Fire, which for the most part bounds the Pacific Plate.[36][37] Massive earthquakes tend to occur along other plate boundaries, too, such as along the Himalayan Mountains.[38]

With the rapid growth of mega-cities such as Mexico City, Tokyo and Tehran, in areas of high seismic risk, some seismologists are warning that a single quake may claim the lives of up to 3 million people.[39]

Induced seismicity

While most earthquakes are caused by movement of the Earth's tectonic plates, human activity can also produce earthquakes. Four main activities contribute to this phenomenon: storing large amounts of water behind a dam (and possibly building an extremely heavy building), drilling and injecting liquid into wells, and by coal mining and oil drilling.[40] Perhaps the best known example is the 2008 Sichuan earthquake in China's Sichuan Province in May; this tremor resulted in 69,227 fatalities and is the 19th deadliest earthquake of all time. The Zipingpu Dam is believed to have fluctuated the pressure of the fault 1,650 feet (503 m) away; this pressure probably increased the power of the earthquake and accelerated the rate of movement for the fault.[41] The greatest earthquake in Australia's history is also claimed to be induced by humanity, through coal mining. The city of Newcastle was built over a large sector of coal mining areas. The earthquake has been reported to be spawned from a fault that reactivated due to the millions of tonnes of rock removed in the mining process.[42]

Measuring and locating earthquakes

Earthquakes can be recorded by seismometers up to great distances, because seismic waves travel through the whole Earth's interior. The absolute magnitude of a quake is conventionally reported by numbers on the Moment magnitude scale (formerly Richter scale, magnitude 7 causing serious damage over large areas), whereas the felt magnitude is reported using the modified Mercalli intensity scale (intensity II–XII).

Every tremor produces different types of seismic waves, which travel through rock with different velocities:

Longitudinal P-waves (shock- or pressure waves)

Transverse S-waves (both body waves)

Surface waves — (Rayleigh and Love waves)

Propagation velocity of the seismic waves ranges from approx. 3 km/s up to 13 km/s, depending on the density and elasticity of the medium. In the Earth's interior the shock- or P waves travel much faster than the S waves (approx. relation 1.7 : 1). The differences in travel time from the epicentre to the observatory are a measure of the distance and can be used to image both sources of quakes and structures within the Earth. Also the depth of the hypocenter can be computed roughly.

In solid rock P-waves travel at about 6 to 7 km per second; the velocity increases within the deep mantle to ~13 km/s. The velocity of S-waves ranges from 2–3 km/s in light sediments and 4–5 km/s in the Earth's crust up to 7 km/s in the deep mantle. As a consequence, the first waves of a distant earthquake arrive at an observatory via the Earth's mantle.

Rule of thumb: On the average, the kilometer distance to the earthquake is the number of seconds between the P and S wave times 8.[43] Slight deviations are caused by inhomogeneities of subsurface structure. By such analyses of seismograms the Earth's core was located in 1913 by Beno Gutenberg.

Earthquakes are not only categorized by their magnitude but also by the place where they occur. The world is divided into 754 Flinn-Engdahl regions (F-E regions), which are based on political and geographical boundaries as well as seismic activity. More active zones are divided into smaller F-E regions whereas less active zones belong to larger F-E regions.

Effects of earthquakes

Shaking and ground rupture

Shaking and ground rupture are the main effects created by earthquakes, principally resulting in more or less severe damage to buildings and other rigid structures. The severity of the local effects depends on the complex combination of the earthquake magnitude, the distance from the epicenter, and the local geological and geomorphological conditions, which may amplify or reduce wave propagation.[44] The ground-shaking is measured by ground acceleration.

Specific local geological, geomorphological, and geostructural features can induce high levels of shaking on the ground surface even from low-intensity earthquakes. This effect is called site or local amplification. It is principally due to the transfer of the seismic motion from hard deep soils to soft superficial soils and to effects of seismic energy focalization owing to typical geometrical setting of the deposits.

Ground rupture is a visible breaking and displacement of the Earth's surface along the trace of the fault, which may be of the order of several metres in the case of major earthquakes. Ground rupture is a major risk for large engineering structures such as dams, bridges and nuclear power stations and requires careful mapping of existing faults to identify any which are likely to break the ground surface within the life of the structure.[45]

Landslides and avalanches

Earthquakes, along with severe storms, volcanic activity, coastal wave attack, and wildfires, can produce slope instability leading to landslides, a major geological hazard. Landslide danger may persist while emergency personnel are attempting rescue.[46]

Fires

Earthquakes can cause fires by damaging electrical power or gas lines. In the event of water mains rupturing and a loss of pressure, it may also become difficult to stop the spread of a fire once it has started. For example, more deaths in the 1906 San Francisco earthquake were caused by fire than by the earthquake itself.[47]

Soil liquefaction

Soil liquefaction occurs when, because of the shaking, water-saturated granular material (such as sand) temporarily loses its strength and transforms from a solid to a liquid. Soil liquefaction may cause rigid structures, like buildings and bridges, to tilt or sink into the liquefied deposits. This can be a devastating effect of earthquakes. For example, in the 1964 Alaska earthquake, soil liquefaction caused many buildings to sink into the ground, eventually collapsing upon themselves.[48]

Tsunami

Tsunamis are long-wavelength, long-period sea waves produced by the sudden or abrupt movement of large volumes of water. In the open ocean the distance between wave crests can surpass 100 kilometers (62 mi), and the wave periods can vary from five minutes to one hour. Such tsunamis travel 600-800 kilometers per hour (373–497 miles per hour), depending on water depth. Large waves produced by an earthquake or a submarine landslide can overrun nearby coastal areas in a matter of minutes. Tsunamis can also travel thousands of kilometers across open ocean and wreak destruction on far shores hours after the earthquake that generated them.[49]

Ordinarily, subduction earthquakes under magnitude 7.5 on the Richter scale do not cause tsunamis, although some instances of this have been recorded. Most destructive tsunamis are caused by earthquakes of magnitude 7.5 or more.[49]

Floods

A flood is an overflow of any amount of water that reaches land.[50] Floods occur usually when the volume of water within a body of water, such as a river or lake, exceeds the total capacity of the formation, and as a result some of the water flows or sits outside of the normal perimeter of the body. However, floods may be secondary effects of earthquakes, if dams are damaged. Earthquakes may cause landslips to dam rivers, which collapse and cause floods.[51]

The terrain below the Sarez Lake in Tajikistan is in danger of catastrophic flood if the landslide dam formed by the earthquake, known as the Usoi Dam, were to fail during a future earthquake. Impact projections suggest the flood could affect roughly 5 million people.[52]

Human impacts

An earthquake may cause injury and loss of life, road and bridge damage, general property damage (which may or may not be covered by earthquake insurance), and collapse or destabilization (potentially leading to future collapse) of buildings. The aftermath may bring disease, lack of basic necessities, and higher insurance premiums.

Major earthquakes

One of the most devastating earthquakes in recorded history occurred on 23 January 1556 in the Shaanxi province, China, killing more than 830,000 people (see 1556 Shaanxi earthquake).[54] Most of the population in the area at the time lived in yaodongs, artificial caves in loess cliffs, many of which collapsed during the catastrophe with great loss of life. The 1976 Tangshan earthquake, with a death toll estimated to be between 240,000 to 655,000, is believed to be the largest earthquake of the 20th century by death toll.[55]

The 1960 Chilean Earthquake is the largest earthquake that has been measured on a seismograph, reaching 9.5 magnitude on 22 May 1960.[28][29] Its epicenter was near Cañete, Chile. The energy released was approximately twice that of the next most powerful earthquake, the Good Friday Earthquake, which was centered in Prince William Sound, Alaska.[56][57] The ten largest recorded earthquakes have all been megathrust earthquakes; however, of these ten, only the 2004 Indian Ocean earthquake is simultaneously one of the deadliest earthquakes in history.

Earthquakes that caused the greatest loss of life, while powerful, were deadly because of their proximity to either heavily populated areas or the ocean, where earthquakes often create tsunamis that can devastate communities thousands of kilometers away. Regions most at risk for great loss of life include those where earthquakes are relatively rare but powerful, and poor regions with lax, unenforced, or nonexistent seismic building codes.

Prediction

Many methods have been developed for predicting the time and place in which earthquakes will occur. Despite considerable research efforts by seismologists, scientifically reproducible predictions cannot yet be made to a specific day or month.[58] However, for well-understood faults the probability that a segment may rupture during the next few decades can be estimated.[59]

Earthquake warning systems have been developed that can provide regional notification of an earthquake in progress, but before the ground surface has begun to move, potentially allowing people within the system's range to seek shelter before the earthquake's impact is felt.

Preparedness

The objective of earthquake engineering is to foresee the impact of earthquakes on buildings and other structures and to design such structures to minimize the risk of damage. Existing structures can be modified by seismic retrofitting to improve their resistance to earthquakes. Earthquake insurance can provide building owners with financial protection against losses resulting from earthquakes.

Emergency management strategies can be employed by a government or organization to mitigate risks and prepare for consequences.

Historical Views

From the lifetime of the Greek philosopher Anaxagoras in the 5th century BCE to the 14th century CE, earthquakes were usually attributed to "air (vapors) in the cavities of the Earth."[60] Thales of Miletus, who lived from 625–547 (BCE) was the only documented person who believed that earthquakes were caused by tension between the earth and water.[60] Other theories existed, including the Greek philosopher Anaxamines' (585–526 BCE) beliefs that short incline episodes of dryness and wetness caused seismic activity. The Greek philosopher Democritus (460–371 BCE) blamed water in general for earthquakes.[60] Pliny the Elder called earthquakes "underground thunderstorms."[60]

Earthquakes in culture

Mythology and religion

In Norse mythology, earthquakes were explained as the violent struggling of the god Loki. When Loki, god of mischief and strife, murdered Baldr, god of beauty and light, he was punished by being bound in a cave with a poisonous serpent placed above his head dripping venom. Loki's wife Sigyn stood by him with a bowl to catch the poison, but whenever she had to empty the bowl the poison dripped on Loki's face, forcing him to jerk his head away and thrash against his bonds, which caused the earth to tremble.[61]

In Greek mythology, Poseidon was the cause and god of earthquakes. When he was in a bad mood, he struck the ground with a trident, causing earthquakes and other calamities. He also used earthquakes to punish and inflict fear upon people as revenge.[62]

In Japanese mythology, Namazu (鯰) is a giant catfish who causes earthquakes. Namazu lives in the mud beneath the earth, and is guarded by the god Kashima who restrains the fish with a stone. When Kashima lets his guard fall, Namazu thrashes about, causing violent earthquakes.

Popular culture

In modern popular culture, the portrayal of earthquakes is shaped by the memory of great cities laid waste, such as Kobe in 1995 or San Francisco in 1906.[63] Fictional earthquakes tend to strike suddenly and without warning.[63] For this reason, stories about earthquakes generally begin with the disaster and focus on its immediate aftermath, as in Short Walk to Daylight (1972), The Ragged Edge (1968) or Aftershock: Earthquake in New York (1998).[63] A notable example is Heinrich von Kleist's classic novella, The Earthquake in Chile, which describes the destruction of Santiago in 1647. Haruki Murakami's short fiction collection after the quake depicts the consequences of the Kobe earthquake of 1995.

The most popular single earthquake in fiction is the hypothetical "Big One" expected of California's San Andreas Fault someday, as depicted in the novels Richter 10 (1996) and Goodbye California (1977) among other works.[63] Jacob M. Appel's widely anthologized short story, A Comparative Seismology, features a con artist who convinces an elderly woman that an apocalyptic earthquake is imminent.[64] In Pleasure Boating in Lituya Bay, one of the stories in Jim Shepard's Like You'd Understand, Anyway, the "Big One" leads to an even more devastating tsunami.

In the film 2012 (2009), solar flares (geologically implausibly) affecting the Earth's core caused massive destabilization of the Earth's crust layers. This created destruction planet-wide with earthquakes and tsunamis, foreseen by the Mayan culture and myth surrounding the last year noted in the Mesoamerican calendar — 2012.

Contemporary depictions of earthquakes in film are variable in the manner in which they reflect human psychological reactions to the actual trauma that can be caused to directly afflicted families and their loved ones.[65] Disaster mental health response research emphasizes the need to be aware of the different roles of loss of family and key community members, loss of home and familiar surroundings, loss of essential supplies and services to maintain survival.[66][67] Particularly for children, the clear availability of caregiving adults who are able to protect, nourish, and clothe them in the aftermath of the earthquake, and to help them make sense of what has befallen them has been shown even more important to their emotional and physical health than the simple giving of provisions.[68] As was observed after other disasters involving destruction and loss of life and their media depictions, such as those of the 2001 World Trade Center Attacks or Hurricane Katrina—and has been recently observed in the 2010 Haiti earthquake, it is also important not to pathologize the reactions to loss and displacement or disruption of governmental administration and services, but rather to validate these reactions, to support constructive problem-solving and reflection as to how one might improve the conditions of those affected.[69]

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General references

 Donald Hyndman, David Hyndman (2009). "Chapter 3: Earthquakes and their causes". Natural Hazards and Disasters (2nd ed.). Brooks/Cole: Cengage Learning. ISBN 0-495-31667-9.

source : http://en.wikipedia.org/wiki/Earthquake