How low can we go? Picking the price of oil

Trying to pick the bottom of oil's surprise price plunge may be tougher this time around, with analysts turning to non-traditional indicators to make predictions.

"Normally, when you have a collapse in a commodity price, it's in response to some supply demand shock," Mark Keenan, a cross-commodity strategist at Societe Generale, told CNBC. "[But] you've actually had a change in the supply and demand curve so you can't really apply traditional shock dynamics."

Like many analysts, he expects oil will fall further, citing a host of bearish supply news, such as expectations the U.S. will export more of its oil and record production levels from Iraq and Russia.

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Just this week, global oil prices have dropped almost 10 percent amid mounting worries about a supply glut. The price of Brent crude for February delivery temporarily fell below $50 per barrel on Wednesday morning for the first time since May 2009. U.S. crude was trading at $47.17 on Wednesday morning.

Alternative tools

One tool Keenan is watching is trade in put options -- or contracts giving the buyer the option to sell assets at a particular price by a set date.

"In the wake of this recent price fall, they've been quite accurate lead indicators of where prices are going to go," he said, noting many puts are being bought on Brent at $40.

The oil storage depot at Indonesian oil company Pertamina in Jakarta
Beawiharta | Reuters
The oil storage depot at Indonesian oil company Pertamina in Jakarta

"Option positions established in Brent tend to be more purposeful and done by quite sophisticated investors because its slightly less liquid and so quite revealing sometimes of where we're going to go," he said.

Beyond that, he's looking to less obvious indicators, such as U.S. employment data, broken down into sectors such as pipeline production, oil extraction and oil services.

"If we start to see changes in these profiles, that would be suggestive certainly that these companies are looking to rein in production and production growth is going to slow," he said.

Keenan's also looking to U.S. railcar traffic, as shale oil tends to be produced in land-locked regions, away from main pipelines and is often transported by rail. He also is looking to oil-drilling rig counts and production per rig.

Misleading?

But some note looking at rigs and production spending might not yield expected results.

Read MoreAs oil breaks $50, Wall Street getting more bearish

Despite expectations North American oil exploration and production (E&P) companies could cut capital spending by as much as 40 percent if oil remains below $60 a barrel, "most E&P companies have high growth profiles, and can cut capital significantly without trimming their current production," Moody's said in a note Tuesday. It cited data from the U.S. Energy Information Administration estimating U.S. oil production will increase by 700,000 barrels a day this year compared with 2014. Moody's only expects a pronounced impact from lower capital spending will emerge in 2016.

Moody's also cited another factor that may limit the readability of rig counts for oil prices: what it called "a tidal wave" of new rig deliveries.

"Many of the existing rigs, particularly jackups, will have to renew contracts in 2015 at significantly lower rates," Moody's said. It expects even larger oil-service companies will need to grant price concessions to customers in upcoming contract renewals to maintain customer relationships and take market share.

Those declining rig costs could persuade oil producers to maintain rig counts and continue producing despite lower oil prices.

—By CNBC.Com's Leslie Shaffer; Follow her on Twitter @LeslieShaffer1