Page 251 - Carbonate Platforms Facies, Sequences, and Evolution

in
has
236
There
gneiss
gneiss
ments,
surface
Wilson
eastern
attempt
Belcher,
(1200 Ma
in
been
American
influenced
wildflysch,
is
by
exist
Neovolcanic
to
ridge
have
Formations).
EARLY
et al.,
Carboniferous
Lopez-Ramos,
late
well
1979;
then
two
belt
Gonzales-Garcia,
NORTHEAST
In
and
major
been
age
strike-slip faulting.
( =
Quachita- Marathon
1972,
900 Ma)
geologists
1984).
Permo-Carboniferous
Sierra Madre,
made
the
Jurassic
southern Chihuahua.
1984;
AND
Mixon,
as
In
Huayacocotla
recorded
its
outcrop
to
PERMO-TRIASSIC
and
1981,
trend
moved
Laramide
attendant
Palaeozoic metasedimentary
by
this
well
MESOZOIC
and
by
1963;
Padilla
show
areas
as
facies and platform construction.
which
1982;
Perigrina
(Guacamaya
y
rocks,
of
paper
is
2000 km N-S).
how
eastward
CENTRAL
some
Mexican
anticlines.
and
Palaeozoic
the
and Cretaceous
Perigrina
OROGENY
the
It
RIFTING
This
outcrops brought
Canyon
and
Charleston,
(Alfonso-Zwanzigger,
reports of this gneiss in the Poza Rica area.
Sanchez,
DeCserna,
resulting from Laramide compressive folding.
against
Grenville
IN
to
Permo-Triassic
distributed
area
areas
AND
MEXICO
or­
metasedi­
fault blocks partly controlled late Jurassic and Cre­
metasediments of the same age (Granjeno schist).
in
gneisses have the same late Proterozoic age as those
1970;
These
Canyons
1981;
sub-surface
It is conjectured that this
consists of early Mesozoic fault blocks which transect
To the north in Coahuila 4000 m of fossiliferous
There exists scattered evidence of an important fold
volcanoclastic and calcareous sediments
1982;
ogeny and perhaps also by left-lateral early Jurassic
belt whose age of deformation and metamorphism is
1978;
clastic flyschoid sediments generally of Permian and
Plomosas
these
the
deformation lies west of and along the front of the
includes
of
Wolfcampian sediments are in tectonic contact with
central Mexico from Chihuahua to the Trans-Mexico
age
taceous facies as well as Tertiary structural patterns
This
one or more Palaeozoic orogenic belts. In turn these
It is generally considered that northeastern Mexico
Permo-Triassic
granite intrusions, and Mesozoic-rifted fault blocks
the
geological
history of this part of Mexico is briefly reviewed. An
carbonate
of
North
&
an
be
J.L. Wilson
ites
A
In
ward
of
are
jectured
INTRODUCTION
mentary
northern
orogenic
island
out
described
important
represents
later time.
better
Schmidt
trend south
of
Triassic
west-trending
and
arc
orogenic belt.
belt,
the
known
Mexico
the
to
orogenic
known
time,
It is
(1983),
pre-Huizachal
facies
Quachita-Marathon
roots
there
left-lateral
Big
of
late
belt
may
where,
Mojave-Sonora
now
south
terrigenous
exist
intrude
of
an
Bend
faulting,
and
have
to Pennsylvanian age inclusive.
after
the
Permian to middle Jurassic (Fig.
trend (Fig.
assumed that
island
clastic
exposed
central
Palaeozoic
region
east
2).
1),
Quachita-Marathon
megashear
extensive
as
arc.
of
of
central
have been intruded by Triassic granites.
of
100 km,
fold
including
displaced
a
belt
part
the
Mexico
(early Mesozoic) age.
curves
the
Texas
the
rocks are seen in outcrops or reached in wells.
of
this granitic
belt,
to
overlie metamorphic rocks reheated in Triassic
Wolfcampian­
anomaly indicates that it abruptly stops as if tran­
south­
The metasediments of the Lampazos­
The belt is conjec­
con­
granodiorites are closely interspersed with metasedi­
Sierra Madre but apart from these no Triassic gran­
Coahuila block basement (McKee eta/., 1988). They
the
Later,
Rhyolitic-
Pennsylvanian through to the Permian and represent
Delicias, Coahuila. They range in age from middle
with olistostromes, occur in an area west of Nueva
tured to underlie the Burro-Peyotes uplift and may
hundreds of kilometres to the north. Table 1 gives a
some
to two wells north of Tampico where
(low metamorphic grade schist) of Siluro-Devonian
its interior portion consists of clastic metasediments
summary of the pertinent localities where Palaeozoic
central
the
dates have been published. They are known only to
first
Anderson
Wolfcampian unmetamorphosed terrigenous clastics
southeast. Originally this may have connected to the
Picacho highs are like the above but no radiometric
or
sected by faulting (Handschy et al., 1987). In Mexico
massif and the more southerly Tezuitlan massif. The
gravity
block offshore of Tampico, the Golden Lane Tuxpan
the
and shallow-emplaced granitic rocks are known at a
into
The intrusives
granodiorite
intrusions whose K/ Ar and R/Sr dates range from
many wells along the Tamaulipas Arch, the Arenque
southeast to Vera Cruz. The granodiorite is seen in
stretch from the Coahuila block at Nueva Delicias,
Palaeozoic
few localities near the Laramide front of the eastern
Pennsylvanian rocks all along their trend. Rhyolites
belt