HUNTINGTON AND GOLDTHWAIT: THE HURRICANE FAULT. 219 
ping toward the east. The most western of these folds is the broad 
gentle syncline in which lies the lava of the Pine Valley mountains. In 
the neighborhood of the mountains the dip is everywhere gentle, and 
the flat bottom of the trough is several miles wide. Toward the south- 
west this syncline almost vanishes, but the western limb seems to persist | 
as an eastward dipping monocline whose lower limit is now the Grand 
Wash fault (Marvine, p. 196). 
The next fold to the east isa remarkable anticline which runs north- 
east eighteen miles from Price City south of St. George to Leeds, where 
it bends more to the north for ten miles, until it is lost under alluvium 
and lava a short distance north of Bellevue. When what seems to be 
the same fold reappears at Kanarra it has again bent somewhat to the 
northeast. Although near St. George this fold is finely exposed as a 
typical breached anticline, that portion fades into insignificance when 
compared with the extraordinarily diagrammatic portion near Harrisburg 
and Leeds. Here erosion has removed all the strata as far as the Shina- 
rump, which at Leeds forms a great rounded nose pitching toward the 
north and shaped like the decked front of a round-topped canoe (Plate 
25). As the anticline rises toward the south, the deck of the nose 
gains a greater elevation, until, halfway from Leeds to Harrisburg, the 
centre is broken open where it has been undermined by the wearing 
away of the soft Moencopie shales. A few miles farther south a five 
minutes’ walk from the road southwest of Harrisburg brings one to the 
top of the Shinarump cliffs on the northwest side of the anticline. 
Under the observer’s feet is the hard Shinarump formation dipping to 
the northwest at an angle of forty degrees. On its resistant surface 
erosion proceeds very slowly, and for many miles this edge of the anti- 
cline forms a ridge. In front ot the observer a precipitous cliff fifty or 
sixty feet high bounds abruptly a perfect anticlinal trough, a mile or 
more wide, a sort of hand specimen or model showing at a glance a dia- 
grammatic type not only of an anticlinal trough, but also of an anticlinal 
ridge. Under the Shinarump cliffs lie the bright-colored Moencopie 
shales, red, gray, and brown, the edges of which are truncated like those 
of the overlying sandstone and conglomerate although at a lesser angle. 
At the very centre lies a little rounded ridge where erosion has laid bare 
the harder underlying Aubrey limestone, which rises as an anticlinal core 
in the midst of an anticlinal trough. Beyond the ridge the naked parti- 
colored shales again rise gradually in brilliant bands to a Shinarump 
' cliff exactly like that on which we are standing, except that it faces in 
the opposite direction and dips to the southeast. 
