Page:Field Notes of Junius Henderson, Notebook 2.pdf/62



Left at 8 p.m. and reached  at 8:30, put up at. Got team at ((left blank)) stable and drove up  thence up  to plot the Arkins fold. West limb of anticline, “Dakota” sandstone and Niobrara dips SW 70˚ to 75˚. W limb of syncline much more gentle as also E limb of anticline. The Dakota forms a high narrow dyke of the hard sandstone. The Fountain is in escarpment. The valley west of granite intrusion is covered, mostly. The upper Lyons is hard, light colored, exactly as in the quarries NW of at. I have not made copious notes on the Arkins anticline and syncline, because they are normal en echelon folds and the map gives about all the data. At the northern end of