Definitely not-for-the-squeamish Delta Air Line's (DAL) stock has plunged in bear-hug fashion during the winter to $9.80 from $14.70, and is now dangerously close to the sell/stop loss at $8.

Delta Air Lines, first discussed here on July 19, 2010, at a price of $10.73, would likely have been a leader of a rejuvenated airline sector until Middle East unrest, including the ongoing civil war in Libya, sent oil prices above $105 per barrel. That crude surge has pushed jet fuel prices -- typically the second biggest or biggest expense for an airline -- substantially higher.

I first wrote about Schlumberger (SLB) here on May 6, 2009, at a price of $56.09. Shares of oil and natural gas servicer have jet-streamed toward major, psychological resistance at $100, easily clearing $90 on the way. It goes without saying that if you haven't already, now would be a good time to consider taking some profits off the table.

However, those investors who can tolerate the risk can maintain their full position and go for an even bigger gain, as SLB will likely continue to head north.

Further, I'd raise the sell/stop loss to $68 from $63.

The U.S. dollar is coming under increasing pressure on several fronts. First and foremost is oil. Oil closed at $102 per barrel Wednesday for the first time in over two years. Oil has been driven upwards by the turmoil in the Middle East. The Libyan situation is getting worse with both sides vowing to fight on. There is unrest throughout the Arab region. The great fear for the West is that oil flows may be disrupted. The U.S. dollar usually moves inversely to oil. Today the March futures closed at 76.689, down .394

The turmoil in the Middle East is spreading as protests surge throughout the Arab world. This is not a one country phenomenon -- and it won't go away any time soon.

The great fear for the West is that the unrest will spread to other oil-producing countries. Half of Libya's oil production is shut down. Protests in Iran -- the second largest oil producer in OPEC -- are growing. Saudi Arabia's King Abdullah is giving away $36 billion to his people in the hope of warding off further unrest.

The most recent datapoint of significance for investors has to be the U.S. Federal Reserve's revised summary of economic projections.

The Fed now sees a stronger U.S. economy in 2011, with the world's largest and most technologically advanced economy expected to grow 3.4% to 3.9%, up from the 3.0% to 3.6% November projection.

The Fed also expects the U.S. economy to grow 3.5% to 4.4% in 2012 and 3.7% to 4.6% in 2013, compared to the November estimates of 3.6% to 4.5% and 3.5% to 4.6%, respectively.

The turmoil in the Middle East is getting worse by the day. Protesters now control a good portion of Libya. The panic is spreading to Saudi Arabia where King Abdullah is handing out $36 billion in housing support and funding to offset inflation, according to the Wall Street Journal.

So the number crunchers are putting together possible "what-if" scenarios for the oil market. One such possibility is: What if Algeria joins Libya in revolt. Both countries produce 4 million barrels of oil per day. If such events develop, oil could surge to $220 per barrel, according to Nomura Securities in the Wall Street Journal.

Chevron (CVX) is one of the largest energy companies in the world and engages in several businesses like exploration and production of oil and natural gas, refining, transportation, trading and chemicals. The company competes with other established oil producers like Exxon Mobil (XOM), ConocoPhillips (COP), BP (BP) and Anadarko (APC). Our price estimate at Trefis for Chevron stands at $102, which is about 5% ahead of the market price.

When it comes to the biggest threat to world economies, oil scarcity is second only to nuclear war. What started in Tunisia, then spread to Egypt has now spreading to Bahrain and Iran, where protesters are clashing with police. In Iran, lawmakers are threatening death to protesters.

The fear of chaos spreading across the Middle East has sent the oil market into overdrive. Brent crude traded at $104 per barrel Tuesday.

After a torrid year, the commodities markets showed some weakness is January. For example, gold fell by about 6%.

So is this a correction or finally a bear market?

Well, legendary investor, Jim Rogers, still thinks that commodities are the best place for your investment dollars (according to an interview on CNBC). No doubt, he has lots of credibility. When others snickered, Rogers started to invest in commodities in the late 1990s. He even wrote a book on the topic.