I think the trader who's making the book for MTR is just very cautious and maybe a little greedy. the volume in very very low recently. I bought 700 shares on Tuesday mid morning and drove the price up 1.25. So look at the daily chart against volume and you'll see he (trader) is just really watching out for himself - as he should. More volume and the market will steady up.
I think it must be a combination of a cautious, perhaps greedy trader, and several investors who are just sick of the position. I recall seeing a sell order for 20,000 shares execute last week. If not for unhappy investors, I can't think what would cause MTR to drop 3.5% on a day like today with O&G at these levels.