Page 192 - Whole Earth Geophysics An Introductory Textbook For Geologists And Geophysicists

cra-
Mountains
show
6.34).
from
commonly
hinterland, the décollement
in
where
accre-
the
(Lillie
the
6.36a), similar
bulge
strata,
al.,
Arc
the
suggest
175
1982)
flexure, active
the
transi-
and
offsetting continen-
mid-crust
may
molasse
the
Ouachita
develop-
6.35c,d;
Range
et
of
Near
in
across
by
continental
Banda
continents
(VanArsdale
interpreted
profiles
(Bachmann
al.,
flexural
6.33,
sediments
the
basins
India
décollement,
synorogenic
oceanic or
flexed
Settings
(Figs.
profiles
1983); undeformed
margin
et
Sulaiman
6.35a-c).
the
the
craton, as
growth
rocks
Ouachita
(Bachmann
(Figs.
6.37).
melts.
the
and
foreland
Seismic
in
km
(Fig.
lithospheric
is
Chapter 8). The
and
two
Tectonic
of the
Reflections
during passive
reflection
at
plate
also
collision,
Pakistan
crystalline
of.the Alps
wedge
15
thin
(Fig.
of partial
.molasse
the
strata
show
faults
et al., 1994; Fig.
collision
the
within
1987),
to
the
the
the
are
6.35c,d).
the
crust
downgoing
the
of
10
between
belt
6.33a, 6.34a).
the Alps
toward
of
of
faults
beneath
accretionary
strata
cover
front
normal
in
than
on
to
Seismic
of
Expression
in
normally
thicker
al.,
foreland
6.36b).
al., 1998).
et_al.,
the
of
synorogenic
fojd-and-thrust
ponding
front
foreland
due
incipient
still
thick
stages
1983; see
(Fig.
normal
et
in
Deformation
more
formed
and
Toward
synorogenic
pushed
collisions in
suturing
is
Lillie
as
reveal
thick
intact
in
vigid,
(Fig.
of the
6.35b}.
deposition
strata
km
(Tomek
basement
1991; Jadoon
interpreted
initial
the
is
Basin
(Figs.
the
to
Seismic
et
Himalayan
an
sheets. Flexural
faults
km
1982;
the
and Watts,
6.35b).
décollement
12
deepens
and
reflections
profiles
1994; Powers
Beneath
remain
the
by
buoyancy
of
of
basin
and
least
(Fig.
Molasse
zones
During
10
in
caused
deformed
foreland
zone
toe
al.,
because
the
advanced
Slovakia
older
strata.
least
the
foreland
(Fig.
thick, because
strata,
of foreland
margin
are
al.,
at
reflection
et
structures
the
basement
subduction
Only
the
the
offsetting
(Karner
(Nelson
Moho
are
at
from
continues, the
Faults
be
seismically
for the
et
faults
older
Strata
at
thrust
are
maintained
a
al.,
for
in
(Humayon
may
preorogenic
of thrust
are
as
strata
of
into
6.37b).
décollement
passive
the
strata
them
1987; Raiverman, et
km
strata
well
as
Normal
cutting
normal
and
strata
Mountains
mountains
of
thickness
Basin
zones
of Arkansas
thickness
and
the
faults
imaged, as well
evolves
of
at
be
5
flysch
top
distinguishing
1979), as
Arkansas, drilling
or
imaged
faults
Fig.
than
advance
margin
front,
strata
profiles
the.
can
Sedimentary
collision
Structures
collision
Foreland
Pakistan
the
is
young
downward,
normal
Flexural
1990;
of
basin
deformed
basement,
Jess
basin
wedge
km
the
the
where
normal
of the
deformation
be
Preorogenic
passive
crust
Carpathian
Mountains
(Montecci,
the
7
and
ment. The
refléction
limits
to
may
Schweig,
in
than
active
As
foreland
foreland
western
L.
2.
uonary
similar
during
be
results
6.36a).
weight
faults,
occurs
the
al.,
tional
1982)
steps
they
that
also
less
and
ton
tal
et
of
in
to
base the near is décollement thrust the If 1986). Yousuf, and (Lillie Himalayas and fault ramp- thrust buttress, causing a as act may fault normal of synorogenic strata, a ramping similar see 1988; Lillie, and 1988; Jaumé al., et 1987; Baker al., et (Lillie ing . 6.34a). wedge, Fig. accretiona

Melt
Profiles Ponded ’ Partial figure). advanced stage of
Reflection (Advanced) (previous figure). an at
Seismic (previous observed
Of Range structures =
Interpretation & 8 8 AN Mantle belt. and structures and prominent reflection sequences (b)
Tectonic Mountain Foreland Fold-ana- Belt strata. faults. fold-and-thrust strata reflections. melt.
And Thrust basin normal involved décollement.
Structural Section i 2 & Signature Foreland Foreland Underthrusted Basement zone reflections. Ponded partial Crustal scale cross section (a)
Flexural
Suture
Thrust
Moho
Chapter6 Coilisional Cross Flexural Bulge Reflection a . NS SF ON WO
.
174 Crustal 6.36 continental collision.
a) b) FIGURE