Arizona weekly citizen., 1891-05-09
COAL FIELDS


Some time since the Citizen pub
llshed an editorial under the above cap
ton. Today the CITIZEN takes pleasure
in laying before its readers an accurate
description of the geological formation
Of the country in which this coal lies.
The report ia official.
The locality OF these deposits appears
| to be that 81 40 embraced between the
San Marcial mountains in the west the
Onavos mountains lying about twenty
miles east OF the Yaqul river, the Baco-
tete mountains on the south and the
Admino table lands rising about sixty
miles to the north, parallelogram
| about 60 miles square.
This great basin is supposed to have
been originally one compact field per-
| haps OF still greater extension. There
seem to have been tremf nduous erup-
tions and upheavals that formed the
San Marcial mountains on the west, the
Adinino high lands in the north and the
Bacotete range on the south. The gen.
eral slope OF the country being from the
back bone OF the Sierra Madre, from east
tc southwest, lake appears to have
| been formed, having as ramparts on the
| west and south the two ranges OF the
| San Marcial and Bacotete, while the de
nudatlon west and south of these noun
taIns continued to scrape the country
| westward and southwark until all that
may have been of the coal measures to-
| wards the sea was ground to dust and
| carried 10 the Gulf of California leaving
nothing but the granite and primitive
! formations which are now visible IN this
part Of western Sonora. Not so within
the enclosure made by the upheavals
of the Santa Marcial and Bacotete
mountains. There the rushing Of the
waters from the highlands OF the Sierra
Madre was arrested forming lake and
depositing on top Of the coal measures
a thick crust OF concrete of several hun
dred feet, which protected the easily
destroyed states and sandstones compos-
ing 1.-THE fields, leaving them in the con-
dition in which they are now found.
How deep or how extensive this lake
or lakes were, may ba copjectured by
following the concrete deposits which ex-
tend from river to river, and from north
to south, fully an area Of 30 to 60 miles
square. Besides the great upheavals
that form the ramparts Of the great
basin, there were also several other
OF much Lesser magnitude, which divide
the the coal basin into three fields
plainly disernible. There is the To
coripa or Vajitos mountains, a low chain
Of hills running parallel to the San
Marcial range, appearing and disappear
ing at intervals, but evidently being one
and the same volcanic eruption and ex-
tending for fully fifty miles north and
oh Isa
sin in two, forming on the west Of it the
OF this middle range there was another
upheaval east and west, from San
Xavier TO the south Of Tecoripa, plainly
marked by backbone of granite that
crosses the country and which pro
duces the two other coal basins of Te-
coripa the north Of it and the Suaqui on
it's southern side. All the mountains
that are formed within the great basin
show at their basin the head of coal
veins, while their cen.ers are invariably
basalt and granite.
Thee fields are located east OF the
Sonora railroad, and the village of San
Marcial which We may call tLeir western
boundary is within twenty miles OF the
Mareno station on the railroad. San
Marcial is sixty miles from Guaymays,
and the way TO reach it now
ia by the train at Ortiz, sta
ton thirty miles from Guaymas and
from there thirty miles more on a grad
ually rising plain of Is feet to the mile
brings you to the village in about six
hours by either horse or carriage. On
your way there the road leads through a
gap in the mountains at place called
Punta de Aqua, where you may yet see
the water line OF the old lake, which at
last cut its way through the solid rock,
dividing the San Marcial from the Ba-
catete mountains. This gap now serves
as an outlet to the Matape or San Mar
ciai river. This same phenomenon is
said to be visible at Buena Vista, where
the Yaqui river has cut its way down the
solid rock, making another outlet for
the imprisoned waters OF the ancient
lake that covered the coal measure.
All these coal lands, covering an area
OF $40 square leagues, are owned by a
Mexican company under Mexican con-
cession to work and extract the mineral
coal in them. For the last year the
company has been engaged in boring in
the San Marcial basin, which is plain
about 20 miles long by seven wide, with
ont counting the sloping of the noun
tains where the beds are tilted at various
angles and working on them would be
inoonvenient. The company is working
a 14 inch Bullock Diamond Drill. The
boring was done at short distance from
where the coal blossoms on the surface
on the slope OF the mountains.
CoMPANIA EXPLoTADoRA DE TERRENoS
CARBoNIFEROS EN- SONORA, MEXICO.
Details of borings made at al Salto"
valley of San Mdrcial: