Read MoreGoldman slashes 2015 oil forecast
He said OPEC may react if WTI reaches $75 or lower. "I think it would stabilize (prices), but the U.S. shale numbers are unbelievable. We're going to be pushing 10 million barrels next year. There's been the questions in the market about oil field depletion, etc. but now there's the realization that it's the real deal."
Goldman Sachs Sunday issued a new forecast for 2015 oil prices for WTI crude to fall to $75 a barrel and Brent to $85 a barrel in the first quarter of 2015, a reduction for both of $15 a barrel from its previous forecast.
WTI could fall as low as $70 in the second quarter and Brent as low as $80, when Goldman expects oversupply would be the most pronounced, before returning to first-quarter levels.
Read MoreThe bad news about below $80 oil
A combination of growing U.S. oil production, now at 8.9 million barrels a day, and weaker growth in global demand has created a supply glut in the Atlantic and plentiful supplies worldwide. Oil production in the U.S. has increased about 500,000 barrel a day, since the summer.
"Oil production is going up in the U.S. over the next year, and the dilemma for OPEC is given the demand forecast, the U.S. and Canada are able to supply the increase in 2015, eliminating the need for OPEC to produce more oil. The increase in demand is going to be met by increases in Canadian and U.S. production, which leaves OPEC on the sidelines," said Andrew Lipow, president of Lipow Oil Associates.
Read MoreSaudi Arabia threatens price war as oil enters bear market
Lipow said new, grassroots investment is affected in the U.S. at $80 to $90 a barrel. He said existing production would not be impacted by low prices until $35 to $40. Citigroup recently forecast that $50 is the level at which production growth would be stopped, and about a quarter of forecast production growth would be impacted at $70 a barrel.
Saudi Arabia, in cutting prices instead of production, was attempting to preserve its market share.
Break-even oil prices for Saudi Arabia, based on budget requirements are at $89 a barrel, but much higher for others like Iraq, which requires $114 a barrel or Iran, at $130 a barrel, according to Citigroup data.
"I actually do think these oil prices are going to force OPEC to act," said Lipow. "Even though Saudis and Kuwaitis could stand an extended period of low prices, they live in a difficult neighborhood and their neighbors cannot endure an extended period of low prices."
Some analysts believe Saudi Arabia, which produces at a much lower cost, could withstand much lower prices than the current break-even estimate. The Kuwait break-even is $44, and it is $71 for Qatar. But Venezuela is at $161 and Libya is at $185, according to Citigroup. Russia, not a member of OPEC, is at $105.