Mesa free press., 1898-06-03

parently 1000 feet thick, in massive
beds dipping gently westward at an
angle of about70 deg. / refer this
sandstone to the Middle Secondary, q
Trias. The same formation appears
to he developed CONTINUOUSLY west-
ward along the north side Of the val
ley as fer as Tempe and beyond and
with about the same dip, but actual
observations along this line of uplift-
ed strata are essential before any
sreci6c description of localities where
artesian water may be looked for with
strong probability of success. 1t can
oply be stated that the stratigraphic
conditions along this line east and
Yest. and north of the Salt River,
gie favorable for artesian, wells. The III
led is tilted up; they are porous and
yater-eearing no doubt, and there
are presumably interstratified imper-
moable layers calculated to retain un-
derlying water. But so far as can be
seen the conditions Of the supply Of
water under the requisite head or
pressure are not favorable TO arteslan
water or flowing wells of any great
volume. We are, however, unable to
state what the undergrocnd sources
Of water are, and we mast not forget
that in this region ut 1T. Verde, or
near there, and close beside the river,
a soldier with few make shift appli-
ances managed to bore we'll to the
depth of 500 feet and obtained mod
crate flow OF artesian water. Whether
this water came from the sandstone
bed or from the deep layers Of river
gravel has not been ascertained. The
records of this boring are very desir-
able as also Of any other bore-holss in
the valley, particularly of horings at
Phoenix which would throw some
light upon the nature of the old river
illusions.
GEOLOGY OF. VIE TUPERsTITIoN HTs.
The Superstition Mountains, rising
about 90 miles east of Mesa and lying
between the Gila and Salt Rivers, are
not as usually shown, one continuous
range extending north and south. The
name should be restricted to the east
and west line Of tables topped hills
extending along she road from Mesa
to Pinal. Instead of continuous
range beyond these hills on the north
there is broad open basin like valley
to which the name Goldfields has been
given. 1t is all open space between
mountains on each side and has the
gsneral elevation of 2300 feet---or
1000 feet above Mesa City. The hills
on the north side of this valley rise
from 500 to 1000 feet higher and are
formed of volcanic tufas and shyolitic
lavas laid down upon granite foun-
datio1.. So also ara the submits Cf
theshills OH the south side volcanic in
origin but are harder and morn por-
phyritic and bilsait,c. The general
dip of all these beds If rlutonic origin
is to the eastward. The floor or foun-
dation of the whole region isa coarse
grained and porphyri.ic granitr. The
distinct fsldspar crystals are generally
from half. All inch TO an inch In diam
-ter. The mica IL. biolise in tine, If
regular scales and evenly spread. The
rock weathers freely end ooes net
appear in bold ridges Of % rugged
aspect but the surface is smooth and
rounded. II is the ancient foundation
arch and appears to extend north
ward to and beyond the, Salt River,
for. the same kind of rock is found at
the head of the Consolidated Irriga-
tion Canal, where the Salt River
comes through the mountains. 1t
there forms the two sides OF the arch
QUITTING through which the water of
the canal is taken out This granite
has at least two interesting peculiar
tiles. II is water-bearing TO al un-
nsual degree, in the Gold6eld region.
and is also auriferous to an unusual
degree. Il bears both water and gold,
two substances much desired in the
Salt River valley.