Stock market corrections usually occur in anticipation of recessions, says one local money manager and investment strategist. We're not there yet, but the present U.S. economy is entering middle age.

America's economic expansions "last longer than in the past, now stretching out five to eight years," said Glenmede's president and chief investment officer, Gordon Fowler.

"The unemployment rate has dropped, but it's not at a level where you begin to worry. What that tells us is the U.S. economy is still growing, earnings can continue to grow, and hence the stock market can grow," Fowler added.

One caveat: The quality of employment has not been as good as in past years, particularly with the rise in temporary workers.

The U.S. stock market "is slightly expensive, although not hugely overvalued," Fowler said, citing a normalized price-to-mid-cycle earnings ratio of 18, versus the long-term average of 15 times earnings.

"We view this as not outrageously expensive - as long as economic news remains good."

Glenmede is overweight in U.S. versus non-U.S. equities, because, Fowler says, "by our measures they're somewhat cheap. The economic news isn't as good but the valuations are attractive."

The drop in crude oil prices is amounting to "a massive tax cut for consumers, and the benefit outweighs the negative effects for our economy," Fowler said.

Those falling oil prices were largely responsible for a big drop in stocks on Friday and the week ending down.

Investors are looking to pick a bottom in oil stocks for some clients, mostly considering the major oil companies, said Chris Millard, of JPMorgan Private Bank in Philadelphia.

"We're avoiding highly levered companies that need a high break-even oil price," Millard added. "There's been enough selling across the market now that you don't need to stretch into the levered names."

For retail investors, the Energy Select Sector SPDR Fund (XLE) is one vehicle to investigate if you want to try to pick a bottom yourself. The exchange-traded fund has dropped from about $100 a share earlier this year to $74.

The fund's top 10 holdings include Exxon Mobil, Chevron, Schlumberger, Kinder Morgan, EOG Resources, ConocoPhillips, Occidental Petroleum, Anadarko Petroleum, Pioneer Natural Resources, and the Williams Cos.