Birch Resources Mows Dean Sandstone for 6.5 MMbbl in 15 Months / Latest / By mark Birch Resources has averaged 7 MMboe, 92% oil, from just 16 wells in the northern Midland Basin’s Dean Formation in an average of 15 months each, according to new Texas Railroad Commission data. Share this: Click to share on Facebook (Opens in new window) Facebook Click to share on X (Opens in new window) X Related