In 1910 Arnold and Johnson published a report on this field, showing a low-angle overthrust fault as the controlling structural feature. Their description has been widely quoted in subsequent literature, and this structure will continue to be referred to as one of the few oil-bearing structures of that type. It therefore seems desirable to have some fresh word on the subject, and particularly whether the last twenty years have brought forth facts which make the original description inaccurate or misleading. Detailed areal mapping by the writer indicates that there is a low-angle overthrust fault present, but that it is complicated by many minor thrusts, and by a series of steep hade strike faults. The latter, rather than the overthrust, determine the position and structur l relationship of the productive sand bodies, though the overthrust shale does at some places form a roof over the productive sands.