The Lisbon Valley uranium projects in the Lisbon Valley Mining District -
approximately 35 miles south of the town of Moab in San Juan County, Utah.
The Lisbon Valley Mining District is a world class uranium -
mining district with past production of over -
85 million pounds of uranium oxide (U3O8).
The prime target is based upon the concept that uranium
deposits occur on the down dropped, northeast block of
the Lisbon Valley fault.
Of the 85 million pounds of U3O8 produced in the District,
63 million pounds were produced from 15 mines that occur
along a mineralized trend that is ½ mile wide and
16 miles long.
This mineralized trend is on the southwestern flank of
a faulted anticline and is primarily hosted by
the Moss Back member of the Triassic Chinle sandstone.
During the 1960's, miners and geologists working in
the district observed this trend and postulated a
genetic relationship between the uranium deposits and
the anticline and determined that more mines might occur
on the northeastern side of the faulted anticline in a
similar pattern as the southwestern flank.
With this geologic framework in mind exploration efforts
focused on the northeastern side of the anticline in
the hopes of discovering what could be the other half of
the District.
The exploration concept was validated in 1968 when a series
of wildcat drill holes intercepted uranium ore on
the northeast side of the anticline.
Drilling defined a massive tabular ore body
roughly ½ mile wide by 1 mile long containing 3 million
tons at a grade of 0.4% for a total of 22 million pounds
of U3O8 produced.
The size and high grade of the deposit justified the
sinking of two 2,300 foot shafts and the construction
of a 700 ton per day mill which produced yellowcake
(uranium oxide - U3O8) in a period when U3O8 prices
averaged $21.00 per pound, the current price is
$138.00 per pound (June, 2007).
The mine was operated by Rio Algom between 1972 and 1988.
The decline of uranium mining in the late 20th century
brought a halt to further exploration until now.
Until the actual targets on the Property are tested they
must be considered conceptual.
Geology
The dominant geologic feature of the Lisbon Valley
is the Lisbon Valley anticline, a salt anticline typical
of the Paradox Basin.
Subsequent to doming the anticline was faulted by
the Lisbon Valley fault, a northwest trending normal
fault along the longitudinal axis of the anticline,
with maximum displacement of over 3,000 feet at
the crest and approximately 2,500 feet at the northwestern
and southeastern ends.
Horst and graben blocks are common along the fault and
are most prevalent at each end of the anticline.
The total stratigraphic section within
the Lisbon Valley anticline measures over 11,000 feet
in thickness.
Sedimentary rocks deposited during Pennsylvanian,
Permian, Triassic, Jurassic, Cretaceous and Quaternary
time are exposed in the Lisbon Valley anticline area.
Uranium deposits are known to occur in three formations
located in the Lisbon Valley.
(1) The Moss Back member of the Chinle Formation
is the most significant in terms of past production and
future targets on the east side of the Lisbon Valley Fault.
(2) Morrison Formation (Salt Wash member), and
(3) the Cutler Formation.
All three formations underlie the
projects primary target areas.
History
Uranium exploration in the Lisbon Valley is entering its
third era of activity.
The previous 2 periods of exploration resulted in a series
of mines stretching for 16 miles forming an actuate belt
of deposits around the Lisbon Valley anticline known as
the Lisbon Valley Mining District.
The earliest reported uranium-vanadium ore discovery was
made in 1913, at the south end of Lisbon Valley anticline
in outcrops of basal Chinle sandstone.
Later in 1948 low-grade uranium was discovered and mined
in the upper Cutler sandstone in the center of
the southwest flank of the anticline.
Prompted by the high demand for uranium and incentive
rewards from the United States Atomic Energy Commission
(AEC), exploration activity in
the Lisbon Valley area increased rapidly.
The host target for the early deposits was
the Permian Cutler formation.
In 1952 while targeting the Cutler Formation,
geologist Charlie Steen drilled into 13 feet
of U3O8 ore (uraninite) in the basal Chinle formation
approximately 100 feet above his planned depth into
the underlying Cutler formation.
Mr. Steen began producing from the Mi Vida mine in 1953.
The discovery of uranium in the basal Chinle Formation
resulted in a new wave of exploration activity.
Following Steen's discovery a dozen companies began
exploring and developing mines in both the Cutler and
the Chinle Formations and shipping the ore to
Salt Lake City and later to Moab.
Imo. Tia.
God Bless
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