HUNTINGTON AND GOLDTHWAIT: THE HURRICANE FAULT. 213 
of variegated shales in which Ward (p. 407) has found numerous remains 
of terrestrial vertebrates. These too “‘are found stratified between the 
sandstones by the transformation of certain shales into marls. If these 
beds are carefully traced a short distance in the direction of the dip, 
they will be seen to thicken very rapidly and soon to take on the char- 
acter of true variegated marls” (p. 409). They start beneath a bed of 
sandstone which thins out to nothing when followed horizontally, while 
at the same time the marl beds thicken greatly and overlap upon beds of 
conglomerate. In brief the Shinarump here consists of beds of very 
varying coarseness which merge into one another, thicken rapidly, or die 
out with the greatest irregularity. In addition to this many layers 
consist of cross-bedded sandstone, others are marly, and still others con- 
tain irregular trains or layers of pebbles. Lastly, the whole formation 
is full of petrified wood, and part contains the fossil remains of land 
animals. All these conditions are unlike those of ordinary marine 
deposition, but are exactly what we should expect in continental deposits 
laid down by streams or in occasional lakes. 
The thin Shinarump deposits near Toquerville and the thick formation 
which occupies a corresponding position near the Little Colorado river 
both show a rapid thinning of the strata toward the great central plateau 
region, This is what would naturally be expected if the deposits were 
subaerial. In the central region, however, to judge from the reports of 
Dutton and others, the Shinarump seems to have a uniform thickness 
over a large area. Such uniformity is characteristic of marine deposits, 
and it may be that part of the Shinarump is marine. It is possible, 
however, that part of the formation was laid down by a retreating or 
oscillating sea, or that the strata were laid down in a shallow basin 
the centre of which was so far from the source of supply that 
the streams could not bring to it more than a few feet of sediment, 
which they distributed with considerable uniformity. As yet we have 
not sufficient evidence to justify us in saying that the Shinarump as 
a whole is either marine or non-marine. It is an open question, but 
the weight of evidence seems to indicate that in part at least it is 
non-marine. 
THE PainteD Desert Pertop. Although the Painted Desert strata 
which succeed those of this doubtful land period contain no fossils, they 
ave supposed to be the result of marine deposition. They are evenly 
' stratified and continue unchanged for long distances. They consist of 
soft sandstones, thin in our area, but nine hundred feet thick along 
the Little Colorado river, 
VOL. XLII. — NO. 5 2 
