Paleoceanography and Paleoclimatology,
Год журнала:
2024,
Номер
39(9)
Опубликована: Авг. 31, 2024
Abstract
The
change
in
vegetation
at
the
margins
of
East
Asian
summer
monsoon
(EASM)
during
Miocene
Climatic
Optimum
(MCO)
remains
poorly
understood.
Here,
we
present
a
high‐resolution
terrestrial
sequence,
paleomagnetically
dated
to
18.2–13.5
Ma,
from
Tongxin
Basin
midwestern
China.
Our
multi‐indicator
analysis,
encompassing
pollen,
δ
13
C
TOC
,
18
O
carb
‐δ
carb,
and
magnetic
susceptibility,
reveals
that
regional
climate
had
two
distinct
stages
MCO,
manifesting
as
stable
arid
steppe
17.0
16.0
woodland
with
six
forested
environments
14.0
Ma.
Together
other
adjacent
records,
this
supports
EASM
main
control
on
vegetation.
Further
comparisons
marine‐terrestrial
data
time
series
analysis
suggest
late
oceanic
carbon
reservoir
(OCR)
experienced
strong
perturbations
(mainly
max
events)
accompanied
by
multiple
oscillations.
instability
signals
likely
impacted
were
amplified
rapid
shifts
forest‐steppe
via
EASM.
study
highlights
regulation
inland
ecologically
vulnerable
areas
low‐latitude
forcing
greenhouse
world.
Geological Society London Special Publications,
Год журнала:
2024,
Номер
549(1)
Опубликована: Май 22, 2024
Within
the
ongoing
controversy
regarding
orogeny
of
Tibetan
Plateau
region,
two
directly
conflicting
endmember
frameworks
have
emerged
in
which
either:
(1)
a
high
central
‘proto-plateau’
existed
before
onset
India–Asia
continental
collision;
or
(2)
early
Paleogene
Tibet
comprised
wide
east–west-oriented
lowland
c.
1–2
km
above
sea-level,
bounded
by
(>4.5
km)
mountain
systems.
Reconstructing
development
plateau
correctly
is
fundamental
to
running
realistic
Earth
system
models
that
explore
monsoon
and
biodiversity
evolution
understanding
interplay
between
dynamics,
landscape
critical
for
future
resource
management.
We
strengths
weaknesses
different
palaeoaltimetric
methodologies
as
applied
across
region.
Combining
methodologies,
appreciating
vulnerabilities
arising
from
their
underlying
assumptions
testing
them
using
numerical
climate
produces
consilience
(agreement),
allowing
further
refinement
both
proxies.
argue
an
Central
Valley
was
cradle
conduit
thermophilic
biota,
seeding
modern
regional
biodiversity.
The
rise
eastern
intensified
rainfall
erosion,
increased
topographic
relief
biodiversification.
Gradual
reflected
evolving
topography,
but
modern-like
Asian
monsoons
developed
only
after
formed
Miocene.
Abstract
The
Cenozoic
growth
history
of
the
northeast
(NE)
Tibetan
Plateau
has
been
strongly
debated
in
past
few
years
with
three
deformation
models
being
proposed:
progressive
northeastward
propagation,
out‐of‐sequence
deformation,
and
episodic
deformation.
Reconstruction
long‐term
exhumation
different
blocks
can
help
elucidate
pattern
tectonic
processes
involved
formation
Plateau.
Both
Qaidam
Jiuquan
basins—the
two
largest
basins
NE
Plateau—contain
continuous
well‐exposed
successions
synorogenic
sediments
that
span
entire
Cenozoic.
We
used
apatite
fission‐track
thermochronology,
sedimentary
facies,
structural
provenance
analyses
these
to
determine
Five
distinct
fast
events
were
recognized
dated:
65–54,
43–39,
34–29,
24–21,
16–15
Ma.
Comparison
existing
morphotectonic
information
enabled
us
reconstruct
a
multiple‐stage
scenario
for
context
surface
uplift
phases
across
Himalayan‐Tibetan
orogen
during
Overall,
our
findings
support
model
emphasizes
current
relief
is
largely
derived
from
five
stage
exhumation.
Journal of Geophysical Research Atmospheres,
Год журнала:
2025,
Номер
130(4)
Опубликована: Фев. 12, 2025
Abstract
The
response
of
the
East
Asian
summer
monsoon
(EASM)
precipitation
to
Pleistocene
global
cooling
is
crucial
for
understanding
Earth's
climate
and
hydrological
cycles.
long‐term
trend
EASM
during
remains
hotly
debated
with
two
main
hypotheses:
one
suggesting
a
gradually
weakening
driven
by
cooling,
whereas
other
proposing
intensifying
influenced
uplift
Tibetan
Plateau
or
strengthening
Pacific
Walker
Circulation.
primary
challenge
in
resolving
this
debate
lies
disentangling
temperature
effects
from
existing
proxies,
which
complicates
interpretation
past
records.
Here,
we
present
new
record
change
North
China,
based
on
soil
dolomite
calcite
contents
that
are
independent
temperature.
Our
results
indicate
increased
interglacial
but
near‐constant
glacial
trend.
This
finding
challenges
conventional
view
weakened
precipitation.
We
propose
evolution
controlled
competition
between
monsoon‐weakening
monsoon‐enhancing
Circulation,
even
could
strengthen
hold
profound
implications
assessing
complex
relationship
hydroclimatic
cycles
temperatures
late
Cenozoic.
Journal of Systematics and Evolution,
Год журнала:
2025,
Номер
63(1), С. 25 - 38
Опубликована: Янв. 1, 2025
Abstract
The
formation
of
the
Qinghai–Tibet
Plateau
has
long
been
debated,
despite
various
proxies
used
to
estimate
its
paleoelevation.
Here,
we
introduce
a
novel
method
calibrate
paleoelevation
by
comparing
fossil
and
extant
plant
communities
in
Plateau.
Our
estimation
confirms
that
uplift
plateau
was
an
episodic
heterochronous
process.
Specifically,
Lhasa
Terrane
already
elevated
1
km
before
initial
India–Asia
collision.
During
first
orogenic
stage,
Qiangtang
rose
faster
than
Terrane,
attaining
3
late
Eocene.
In
second
underwent
rapid
uplift,
reaching
Oligocene.
By
Middle
Miocene,
both
terranes
had
achieved
elevation
4
km.
Himalaya
at
least
2
after
Pliocene.
biological
knowledge‐based
findings
contradict
previous
geological
evidence‐based
reports,
which
posited
reached
4–5
during
We
provide
new
perspective
on
plateau′s
history
based
evidence,
potential
reconcile
confusion
arising
from
contradictory
proxies.
The Innovation Geoscience,
Год журнала:
2023,
Номер
1(2), С. 100020 - 100020
Опубликована: Янв. 1, 2023
<p>Asia
has
a
unique
set
of
landscapes,
notably
characterized
by
the
highest
plateau
in
world,
strongest
monsoon
circulation,
and
an
immense
arid
region.
When
how
this
landscape
was
formed
have
long
been
investigated,
but
explanations
remain
elusive.
In
paper,
through
synthesis
both
terrestrial
marginal
marine
sedimentary
records
numerical
simulation
analyses,
we
propose
that
tectonic
uplift/deformation
global
cooling
during
Cenozoic
controlled
evolution
Asian
topography
climate,
respectively,
and,
landscape.
The
undergone
three
main
stages
evolution,
<i>viz</i>:
development
low-relief
warm-dry
climate
Eocene
(~50-34
Ma);
emergence
high
relief
southwest,
along
with
diverse
range
landforms
elsewhere,
associated
warm
monsoon-arid
coupling
system
Oligocene
to
early
Pliocene
(34-3.0
typical
summer
winter
circulation
present
since
late
Pliocene,
accompanied
significant
cooling.
Our
analyses
reveal
distribution
river
catchments,
flora,
fauna
soils
are
palaeoclimate
changes.
Stepwise
~50
Ma
driven
deformation
temperature
changes,
each
which
may
play
different
role(s)
evolution.
For
instance,
India-Asia
collision
played
vital
role
formation
topographic
configuration
middle
Eocene,
generated
regional
atmospheric
circulation.
On
other
hand,
important
generating
modern-like
including
rapid
accumulation
loess
deposits,
strengthening
modern
topography.
To
summarize,
broadly
three-stage
history
Asia
Cenozoic.
detailed
processes
specific
roles
tectonism
controlling
landscapes
need
be
further
investigated.</p>
