The
Santos
basin
pre-salt
fields
are
located
300
kilometres
offshore,
in
waters
of
about
2300
metres
and
at
depths
of
between
5000
and
7000
metres.
The
logistical
and
field
development
challenges
are
still
formidable
but,
with
a
handful
of
ultradeepwater
rigs
and
a
little
help
from
one
or
two
international
oil
companies,
Petrobras
has
virtually
proven
that
the
Brazilian
pre-salt
harbours
at
least
30
billion
barrels
of
recoverable
crude,
and
has
the
potential
to
yield
much
more.
As
the
rig
fleet
grows
and
drilling
steps
up,
conservative
estimates
now
point
to
between
30…
