There is always a reason for a price move like this along with a pick up in volume. This appears to have started yesterday. My guess is some major institutional fund is adding a position. When they add in a "short" period of time this will move the stock price up. Of course it could be many players adding. Why now? Maybe a rumor of a hit in the exploration wells in the Black Warrior Basin. There is a 6 month blackout period between a strike and when it is made public. But Chesapeake is dilling also and that stock has not moved. Anyone's guess. GRock
There is no fundamental reason for the increase though. The way the stock is acting it almost looks like there is a buyout on the way. Other possibilities might be a stock split combined with a dividend increase and/or stock buyback. There must be something behind this unusual increase.