Has
The
Rincon
de
la
Vieja
Awakened?
It
has
been
14
years
since
the
last
eruptive
period
for
Rincón
de
la
Vieja
in
Costa
Rica,
but
it
looks
like
the
volcano
might
be
awakening
from
its
break.
An undated image of Rincón
de la Vieja in Costa Rica.
The active crater is seen in
the foreground with a small
crater lake. The lake
between the active crater
and the forested crater is
Los Jilgueros. Santa Maria
volcano is seen in the far
background. Image: Eliecer
Duarte (OVSICORI-UNA) |
Last
Thursday
(Feb.
22),
the
volcano
experienced
two
small
explosions
in
the
early
morning.
Seismic
records
suggest
the
volcano
also
had
small
explosions
on
Feb.
19
and
20,
according
to
the
OVSICORI
report
for
Feb.
25.
None
of
the
explosions
caused
any
damage
to
anything
near
the
volcano
and
there
are
no
reports
of
ash
fall
other
than
in
the
crater
itself.
These
explosions
are
very
similar
in
style
to
the
September
2011
explosions
that
were
like
phreatic
in
nature
—
that
is,
not
new
magma
but
superheated
water
generated
the
explosions.
Of
course,
it
is
likely
that
new
magma
intruding
the
volcano
is
the
heat
source
for
the
water,
but
these
explosions
could
precede
a
new
magmatic
eruption
by
months
or
years
(or
lead
to
nothing
at
all).
The
volcano
sits
within
a
national
park
in
Costa
Rica
and
after
these
explosions,
the
National
Emergency
Commission
has
declared
the
crater
area
off-limits
to
visitors.
The
last
major
eruption
from
Rincón
de
la
Vieja
was
in
1966,
when
it
produced
at
VEI
3
event
that
generated
pyroclastic
flows.
All
the
way
back
in
circa
1820
B.C.,
the
volcano
produced
the
Río
Blanco
tephra
from
a
larger
VEI
4
eruption.
The
summit
of
the
volcano
hosts
a
small
crater
lake
(see
above),
which
could
potentially
add
to
the
initial
explosivity
of
any
eruption
as
the
water
interacts
with
erupting
magma.
There
are
also
abundant
mudpots
and
springs
within
the
national
park
as
well,
attesting
to
the
persistent
geothermal
activity
in
the
area.
This
geothermal
activity
is
the
reason
why
the
Costa
Rican
government
is
looking
to
build
a
200
MW
geothermal
energy
plant
in
the
National
Park
as
well.
By
Erik
Klemetti,
Wired.com