Earthquakes and tsunamis, such as the powerful quake that occurred today in the South Pacific and wave it generated, can often go hand-in-hand.

Tsunamis, which can travel over the ocean surface from many hundreds of miles, can be generated when chunks of the planet's crust separate under the seafloor, causing an earthquake. Today's temblor was put at magnitude 8.0 by the U.S. Geological Survey. The potential height of the tsunami is not yet known.

Here's what happens: One slab of lifting crust essentially rapidly acts as a giant paddle, transferring its energy to the water.

Tsunamis can also be caused by volcanic eruptions, underwater detonations and even landslides.

Exactly what caused today's tsunami is not yet clear. And officials have been scrambling to issue watches and warnings and estimate what might occur.

The resulting waves are hard to predict for several reasons. Nobody knows how a quake has affected the seafloor until hours, days or even months after the event. And a tsunami is almost imperceptible on the open ocean, rising to full ferocity only as it nears the shore.

While more tsunami-sensing buoys cover the ocean than before the devastating 2004 Indian Ocean tsunami, these waves can still be missed.

Not all seafloor earthquakes will generate a tsunami - if the friction between the crustal plates occurs very deep below the ocean floor or move in a way that causes a minimal paddle effect, a tsunami isn't as likely to form.

The 2004 quake just off the coast of Sumatra, Indonesia, was colossal, eventually put at magnitude 9.3. But an 8.7-magnitude earthquake in 2005 that originated at the same location, while large enough to generate a devastating tsunami, scientists say, did not do so. The exact reasons remain mysterious.

The 2004 tsunami, and those spurred by the 9.2-magnitude Great Alaska Earthquake in 1964, were examples of teletsunamis, which can cross entire oceans.

Several devastating tsunamis have occurred throughout recorded history, including one that leveled Lisbon, Portugal in 1755 and one generated by the explosion of Krakatoa in Indonesia that drowned an estimated 36,000 people.

Except for the largest tsunamis, such as the 2004 Indian Ocean event, most tsunamis do not result in giant breaking waves; instead they come in much like very strong and fast-moving tides, according to the U.S. Geological Survey. As a tsunami nears the shoreline, the rising seafloor forces a wave that might have been just inches tall into a monster that can be several feet high.

The Pacific Ocean basin is particularly prone to tsunamis; a study earlier this year found that the tsunami risk to the west coast of the United States was higher than previously thought.

Video - Recreating an Ancient Tsunami
Tsunamis: The Grave, Global and Unpredictable Threat
West Coast Tsunami Risk Higher Than Thought
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WASHINGTON (Reuters) –
The U.S. Federal Reserve on Tuesday proposed tough new credit card rules to protect consumers from potentially costly practices by lenders and moved to implement legislation enacted in May.

"This proposal is another step forward in the Federal Reserve's efforts to ensure that consumers who rely on credit cards are treated fairly," said Fed Board Governor Elizabeth Duke said in a statement.

The proposals, issued for public comment, represent part of the Fed's implementation of the Credit Card Act, which was signed into law by President Barack Obama in May.

The Fed adopted final rules prohibiting unfair credit card practices in December 2008. The proposals released on Tuesday amend those regulations to incorporate provisions in the new credit card law.

"The rule bans several harmful practices and requires greater transparency in the disclosure of the terms and conditions of credit card accounts," Duke said.

They would protect consumers from unexpected increases in credit card interest rates by generally prohibiting a rate rise in the first year after an account is opened, and increases in a rate that applies to an existing car balance.

They would also prohibit creditors issuing a card to anyone under the age of 21 unless the borrower has either the ability to make the required payment, or has the signature of a parent or other co-signer who has the means to do so.

In addition, the proposed rules would mean a consumer's consent would be needed before creditors could charge fees for transactions that exceed the credit limit, and curb fees linked to subprime cards for consumers with risky credit.

They would also ban "two-cycle" billing methods, where a creditor raises an interest rate and charges the higher rate for a customers' previous borrowing.

NEW YORK – President Obama's decision to travel to Copenhagen to boost Chicago's chances of winning the 2016 Olympics has drawn criticism from some Republicans, who call it a boondoggle for Obama's hometown allies and evidence the president has blurred his priorities.
Republican National Committee Chairman Michael Steele denounced the visit on a conference call with reporters Tuesday. Calling it "noble for the president to pitch his home city, Chi-town," before the International Olympic Committee Friday, Steele said it nonetheless was a distraction from more pressing issues such as health care, job creation and other urgent demands on Obama's time.
However, Mitt Romney, the former Massachusetts governor and 2008 Republican presidential contender, said Obama was right to make an appearance.
"In the current environment, the presence of a head of state is important to get the Games," Romney, who headed the 2002 Olympics in Salt Lake City, Utah, said, noting that former British Prime Minister Tony Blair had set a new standard by personally lobbying for his country's succesful 2012 Olympic bid.
Steele said it raised questions about Obama's priorities.
"Where is the focus?" Steele asked. "At a time of war, at a time of recession ... I think this trip is nice but not necessary for the president. The goal should be creating job opportunities not seven years from now, but job opportunities today."
White House spokesman Robert Gibbs laughed when told of Steele's criticism of Obama's trip.
"Who's he rooting for?" Robert Gibbs said. "Is he hoping to hop a plane to Brazil and catch the Olympics in Rio? I don't know. Maybe it's Madrid."
Steele's comments echoed those of Rep. Peter Hoekstra of Michigan, the ranking GOP member of the House Intelligence Committee, who told reporters Obama should focus on the escalating conflict in Afghanistan.
Just last week Obama said he wouldn't make the trip to Copenhagen, citing his need to press for health care reform legislation instead. White House officials mentioned the economic benefits the U.S. would receive from a winning Olympics bid in explaining the president's sudden change of heart.
First Lady Michelle Obama was originally slated to represent Chicago before the IOC but will now share the duties with her husband.
The city's bid is competing with bids from Rio de Janeiro, Madrid, Spain and Tokyo, and the heads of state from Brazil, Spain and Japan are appearing in person to make their countries' pitch.
Indeed, Curt Hamakawa, director of the Center for International Sport Business at Western New England College in Massachusetts, said Chicago would likely lose the bid if Obama had chosen not to go.
"For the president not to attend would send a signal, and it would not be helpful to Chicago's bid. Almost certainly it would result in Chicago not having a chance," Hamakawa said, adding that if Obama had stayed home and Chicago wasn't selected, "Republicans would have been crabbing that he didn't do enough."
GOP strategist John Feehery said it was important for Republicans to pick their battles in deciding how and when to criticize Obama.
But Feehery, a Chicago native who said he is rooting for the city to win the Games, said GOP complaints about Obama's trip were well-founded.
"He's taking a bunch of Chicago cronies on an all expense paid trip to Copenhagen for just one reason, to get the Olympics," Feehery said. "For me it makes him seem unserious and look slightly desperate."
Grumbling about Obama's trip began to bubble up on conservative blogs and Web sites soon after the White House announced Obama's trip Monday.

"It's not like the president doesn't have anything to do, nothing important on his plate at the moment, right?" the blog Rightwing Nuthouse.com asked, while the conservative Drudge Report posted a television news story about a Chicago teen beaten and murdered in gang warfare there last week.

"Olympic Spirit," the Drudge Report declared in a headline.

NEW YORK (Reuters) –
Sarah Palin, last year's Republican vice-presidential candidate who became a figure of global fascination, is to release her memoir just four months after her book deal was announced.

Publisher HarperCollins said Palin's memoir, titled "Going Rogue: An American Life", would be published on November 17 after originally being scheduled for release in spring 2010.

The book will have a large first printing of 1.5 million copies, according to a statement from HarperCollins, a unit of Rupert Murdoch's News Corp.

Senator Edward Kennedy's memoir "True Compass", published soon after his August 25 death, also had an initial print run of 1.5 million hardcover copies.

Palin, 45, the brash and deeply conservative former governor of Alaska, burst onto the U.S. and international scene last year when Republican presidential nominee Senator John McCain picked her as his running mate in the 2008 election campaign.

She has not disclosed how much she would be paid by the publisher for her memoir.

At the time the book deal was announced, Palin said in a interview published in Alaska's Anchorage Daily News that it would be good to have an "unfiltered forum" as "there have been so many things written and said through mainstream media that have not been accurate."

During the electoral campaign she was criticized for being inexperienced and for describing herself as a "hockey mom", joking that the difference between a hockey mom and a pitbull was lipstick.

The former beauty queen was ridiculed for saying her foreign policy experience was bolstered by Alaska's proximity to Russia across the Bering Strait. Her family also came under scrutiny when her 18-year-old unwed daughter Bristol had a baby.

Palin abruptly resigned as Alaska's governor in July, citing a variety of reasons for quitting - the burden of fighting nearly two dozen ethic charges which she had dismissed as "frivolous", her desire to avoid being perceived as a powerless "lame-duck" governor, and a "higher calling", among others.

(Writing by Belinda Goldsmith, Editing by Miral Fahmy)