But is the move in these stocks over, or is there more to come?
Hints come from the American Association of Railroads' weekly traffic reports. The AAR reports numbers not just on U.S. railroads, but on those in Canada and Mexico as well.
Petroleum, metal and stone traffic rose 3.6% from a year ago at the end of June, the AAR, said, and total traffic is up 4.5% from this time in 2013. Much of the metal and stone being shipped is aimed at oil production.
Intermodal units, rail cars that become truck loads at their destination, are also up almost 6%, indicating a growing economy. This provides further lift to the rail sector.
According to the AAR, Canadian rail traffic is up only 2.4% against a year ago, while total traffic within the U.S. is up 4.5%. Mexico traffic is up only 2.2% so far this year, against a year ago.
It is the U.S. rail market that is powering ahead most rapidly.
We've seen oil tied to rail traffic before, a long time ago. Back in the 1870s, before the Tidewater pipeline was able to move product from the west Pennsylvania oil fields to coastal refineries, rail was the main way oil went to market.
Many new fields today are far beyond the reach of current pipelines, which can cost many years to approve and build. So rail is being relied upon again.
Much of Union Pacific's value to the play lies in north-south routes that can take crude to Gulf Coast refineries, and oilfield equipment, north. But some of those operations are vulnerable to pipeline competition -- the Seaway pipeline from Oklahoma to Houston was reversed in 2012 and its capacity is now being doubled by construction of a twin line. This will provide competition to Union Pacific in that part of its network.