El Paso daily herald. (El Paso, Tex.) 1881-1901, 1900-01-13

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of which it is the commercial center.
The valley of the Rio Grande. in which
Ell Paso is situated, is some 5000 feet
below the exceptional mountain peaks,
and about 200 feet lower than the So
called stmesas" >or basins between
the mountain peaks and ranges.
Hence, if the structural and
rainfall conditions prove favor
able no topographic difficulty will
prevent securing water at Ell Paso.
That the amount of rainfall is suf-
| fciept to supply artesian water for the
proportion of habitable country upon
which it falls will be shown later; this
leaves the possibility of procuring ar
tesian water dependent upon structur-
| al conditions.
THE GEOLOGIC STRUCTURE OF Ell
| PASO AND VICINITY.
While apparently complicated and
replete with problems of scientific in
terest, irrelevant to the purpose OF
this region may be classified under
three distinct and familiar classes,
mountains, basins, Tor mesas), and rlv-
err valley. Each is radically different
from the others in origin, structure
and water imbibing and transmitting
capacities and q ill be discussed sepa-
rately.
There Is large mass of rock ip the
trans-Pecos region of Texas, New
Mexico and in Mexico which stands
sharply above the general plain of tae
country il mountain ranges or isolated
blocks which are very suggestive OF
vast receiving and storage area for an
artesian supply. In the immediate
vicinity of Ell Paso there are (U, the
Franklin mountains beginning in the
nd rd
into New Mexico, as part of the
Organ system: (2), the Juarez noun
tains southwest of the city in Mexico
and New Mexico. Situated in sight of
the city but from 30 to 100 miles dist
ant are the Huecos, and to the east,
with its prominent peaks the Sierra
Alta. To the southeast are numerous
unnamed mountain blocks or peaks
rising from the common plain; while
Mexico another north and south line
of mountains.
None of these more remote noun
tains can have 8 direct structural
bearing upon the Ell Paso artesisn sup
ply, although in the case of the Sierra
Hueco there may be an Indirect con-
tribution through the mesa. The more
distant mountains can not transmit
their waters to this vicinity because In
no case do their rocks-even If OF suffi-
cient porosity to imbibe and trausmit
mOisture-dip or extend beneath Ell
PasO, but they are broken, discOnnect-
ed and torn apart by the great strains
to which they have been subjected, and.
in most cases, their strata incline away
from the Rio Graude valley; the same
reason removes the small mountainous
possible supply. These facts being
admitted the noun tains Immediately
ad jacent to the city remain the only
sources of mountain investigation.
These mountains are Q) the Franklin
mountain northeast Of the city; ~ a
lower, more rounded, and unnamed
outline Immediately west of Mt. Frank
a series of sharp, jagged, granitic hills
north of Fort Bliss; az Monument
mountain Immediately west of the
river at its section with the New Mex
leo line.
The rocks of the eastern slope of
Monument mountain, and the Little
Mesa north of it, dip southesstward
toward Ell Psso. but cas- of the smelter
their continuity is broken by the in
trusion of the immense mass of granite
(syenite) sheet which composes the
Fort Bliss hills. This syenite, as
shown by Mr.. Detweiler's' experiment,
is more than 700 feet thick IN the
northwest city limits, and is an insur-
noun table barrier against procuring
artesian water at q reasonable cost, if
at all, and / would not advise another
experiment in it. But If any think
water can be obtained beneath it, the
cheapest test would be to continue the
present Detweiler we'll not more than
500 feet.
Mt. Franklin and its western foot
hill now remain the only mountain
areas to be discussed. 1 have carefully
examined their structure including the
clination, and capacity for absorbing
and transmitting the rain that falls
upon them.
With the exception of a small area
near McKelligon's house, the soutbaeSR
half OF the mountain is composed Of
massive, impervious limestoneot greas |
age and hardness, resting upon 100 feet |
of equally hard aud impervious quart
zite, or metamorphosed sandstone as |
exposed ON the southeastern slope. |
Beneath the latter is mass of gran
lite rock, probably an intrusive sheet,
and beneath this the structure is con-
cesled by the mesa formation. These
rocks incline towards Ell Paso. The
northern half of the mountain consists
OF equally bard quartzites and shsIes
more than 10 900 feet in thickness, csp-
ped and underla'd by igneous rocks,
granite and basalt. The northern sys-
tenn of rocks rests unconformably upon
the older or southern half and dips
north of westward or away from Ell
Paso.
It is a remarkable fact that all these
rocks are so impervious that they are
incapable of mbibinE, except through
issures, more than a small per cent Of
;he rainfall upon them, and their capa-
,ity for inhibition may be estimated at
The minimum. The total superficial