Seismic stratigraphy of the Plio-Pleistocene Giant Foresets, Western Platform, Taranaki Basin


Beggs, J.M.

4th New Zealand Oil Exploration Conference 1: 201-207

1991


Rapid uplift along the Alpine/Hikurangi plate boundary since the Miocene has resulted in an abundant supply of clastic sediment to adjacent basins. Within Taranaki Basin, the southern graben was filled by the end of the Miocene, since when the continental shelf has prograded westward across the Western Platform. The northern West Coast of South Island has been the primary source of sediment for the Plio-Pleistocene construction of the continental shelf on the Western Platform. Sedimentation at the shelf margin has been largely confined to sea-level lowstands, whereas highstands are characterised by shelf aggradation. The Pliocene and Pleistocene section on the Western Platform is up to 2.2 km thick and comprises a spectacular seismic-stratigraphic unit, the Giant Foresets. Seismic character and stratal patterns in the Giant Foresets define the following facies: Topset: subparallel continuous reflectors; Progradational foresets: coherent offlapping moderate amplitude reflectors; Degradational foresets: chaotic offlapping low-amplitude reflectors; Bottomset: moderate amplitude, variable continuity subhorizontal reflectors. Typical transects include varying proportions of these facies, depending mainly on antecedent physiography. The Giant Foresets comprise over half the stratigraphic thickness of much of the Western Platform and the attending loading must exert a critical impact on the thermal history of the underlying sequence. Additionally, an understanding of the Plio-Pleistocene depositional style can be applied to similar units, mainly of Miocene and younger age, in several New Zealand basins.

SEISMIC
STRATIGRAPHY
OF
THE
PLIO-PLEISTOCENE
GIANT
FORESETS,
WESTERN
PLATFORM,
TARANAKI
BASIN
J
M
Beggs
New
Zealand
Geological
Survey
..
..
. .
Rapid
uplift
along
the
Alpine/Hikinangi
Plate
boundary
since
the
Miocene
has
resulted
in
an
abundant
supply
of
claStie
.
sediment
to
adjacent
basins;:
Within..
Taranaki
Basin,
the
southern
graben
was
filled
by
the
end
of
the
Miocene;
since
when
the
continental
shelf
has
Prograded
westward
abross
the
Western
Platform.
The
northern
West.
Coast
of
South
Island
has
been
the
primary
source
of
sediment
for
the
Plio-Pleistocene
ecinstructiOn
of
the
continental
shelf
on
the
Western
Platform
Sedimentation
at:the
shelf
margin
has
been
largely
Confined
lowstands,
whereaS
highstands
are
charaeterised
by
Shelf
aggradation.
The
Pliocene
-
and
Pleistocene
section
on
the
Western
Platform
is
up
to
2.2
km
thick
and
comprises'
a
spectacular
seismicstratigraphic
unit,
the
GiantForesets.
-
.
Seismic
character
and
stratal
patterns'in
the
Giant
Foresets
define
the
following
facies
Topset:
subparallel
continuous
reflectors
Progradational
foreset:
coherent
offlapping
moderate
amplitude
reflector
.
.
Degradational
foreset:
chaotic
offlapping
low-amplitude
reflectors
Bottornset:
moderate
amplitude,
variable
continuity
subhorizontal
reflectors
Typical
transects
include
varying
proportions
of
these
facies,
depending
mainly'on
antecedent
physiography..
The
Giant
Foresets
comprise
over
half
the
stratigraphic
thickness
of
much
of
the
Western
Platform
and
the
attendant
loading
must
exert
a
critical
impact
on
the
thermal
history
of
the
underlying
sequence.
Additionally,
an
understanding
of
the
Plio-Pleistocene
depositional
style
can
be
applied
to
similar
units,
mainly
of
Miocene
and
younger'age,
in
several
New
Zealand
basins.
INTRODUCTION
The
term
Giant
Foresets
was
first
used
in
a
stratigraphic
context
in
Taranaki
Basin
by
Shell
BP
Todd
(1977)
for
a
stratigraphic
unit
that
is
best
defined
with
reference
to
its
seismic
expression
(Fig.
1).
It
is
actually
the
thickest
unit
in
the
stratigraphic
section
over
much
of
the
Western
Platform,
in
spite
of
encompassing
no
more
than
5
million
years
in
a
total
sedimentary
record
exceeding
60
million
years.
The
distinctive
clinoform
seismic
character
of
the
Giant
Foresets
records
the
westward
and
northward
growth
of
the
continental
shelf,
a
process
which
really
began
in
the
early
Miocene
with
the
initiation
of
mountain-building
following
the
development
of
the
convergent/transform
plate
bound-
ary
(Alpine
Fault-Hikurangi
Subduction
Zone)
(Walcott,
1978).
This
paper
examines
the
extent
and
internal
characteristics
of
the
Giant
Foresets,
the
processes
responsible
for
its
formation,
and
some
of
the
implications
for
possible
petro-
leum
generation
and
entrapment
on
the
Western
Platform
of
the
Taranaki
Basin.
DISTRIBUTION
Thrasher
and
Cahill
(1989)
have
mapped
the
thickness
of
the
Giant
Foresets
on
the
Western
Platform
using
seismic
data.
The
unit's
shape
is
essentially
sigmoidal,
as
are
its
internal
components.
The
structure
(and
antecedent
geology)
of
the
base
of
the
Pliocene
on
the
Western
Platform
is
shown
by
Fig.
2
(from
Thrasher
and
Cahill,
1989).
The
main
elements
are:
(a)
The
pre-existing
west-dipping
foreset
slope
of
the
upper-
most
Miocene
(the
southern
Taranaki
Graben
having
been
filled
by
similar
offlapping
facies
during
the
Miocene:
see
Fig.
28
of
Hayward,
1987).
(b)
The
bathyal
head
of
the
New
Caledonia
Basin
to
the
northwest,
fed
by
an
extensive
submarine
canyon
system
with
up-dip
terminations
on
the
slope.
(c)
An
area
of
erosional
relief
into
Miocene
and
older
rocks
in
the
south
of
Taranaki
Basin,
extending
north
across
the
Maui
Field
region
to
the
west
of
Cape
Egmont.
The
Southern
Alps
and
possibly
also
the
axial
ranges
of
the
North
Island
were
undergoing
uplift
and
shedding
a
substan-
tial
volume
of
sediments
into
the
adjacent
basins.
The
broad,
shallow
Wanganui
Basin
was
beginning
to
subside
after
a
pulse
of
folding
and
compressional
faulting
extending
into
the
southern
Taranaki
Basin
at
the
very
end
of
the
Miocene.
SEISMIC
FACIES
On
the
basis
of
seismic
character,
four
seismic
facies
(Fig.
3)
are
recognised
within
the
Giant
Foresets:
201
TWT(s)
31-NNI
-
207
Fig.
1:
Example
seismic
line
showing
the
clinoform
nature
of
the
Giant
Foresets
on
the
Western
Platform.
Topset
(Fig.
3a,
3b):
subparallel,
subhorizontal,
moderately
continuous
moderate-high
amplitude
reflectors.
Well
pene-
trations
reveal
cyclic
lithologic
sequences
including
sand-
stone,
muddy
siltstone,
and
shellbeds.
Faunal
assemblages
indicate
neritic
bathymetric
conditions.
Sedimentation
rates
are
essentially
equal
to
subsidence
rates.
Progradational
Foreset
(Fig.
3a):
offlapping,
moderately
continuous,
coherent
moderate
amplitude
reflectors
dipping
basinward
at
1-3°.
Wells
indicate
that
this
facies
comprises
monotonous
mudstones
and
muddy
siltstones.
Faunal
as-
semblages
typically
reflect
rapid
shallowing
through
this
facies
from
bathyal
to
neritic
conditions;
sedimentation
rates
exceed
subsidence
rate
(Hayward,
1987).
Degradational
Foreset
(Fig.
3b,
3c):
offlapping,
discon-
tinuous,
variable
amplitude
reflectors
with
set
boundaries
dipping
basinward
at
up
to
10°.
Wells
through
this
facies
reveal
heterogeneous
lithologies,
dominated
by
mudstone
but
with
sporadic
sandstone
and
conglomerate
beds.
Faunal
content
is
similar
to
the
progradational
foreset
facies.
Bottomset
(Fig.
3b,
c):
variable
continuity,
generally
mod-
erate
to
low
amplitude,
subhorizontal
to
slightly
inclined
reflectors.
Lithological
content
in
wells
is
variable,
includ-
ing
sandstones
and
mudstones.
Faunal
content
indicates
bathyal
environments,
and
variable
depositional
rates.
Interpretation
Combination
of
the
seismic
and
geological
evidence
sug-
gests
that
these
seismic
facies
form
in
response
to
different
depositional
circumstances.
Of
particular
importance
is
the
configuration
of
the
shelf
margin
and
slope
at
the
time
of
sedimentation.
When
sediment
supply
exceeds
the
space
available
on
the
shelf
(the
width
of
which
varies
according
to
relative
sea
level,
as
discussed
further
below),
excess
sediment
is
delivered
across
the
shelf
margin
onto
the
slope.
Where
the
slope
is
smooth
and
gently
dipping,
the
resulting
deposit
is
of
the
progradational
foreset
facies,
but
since
each
wedge
of
sediment
tends
to
be
incrementally
thicker
at
its
up-slope
end,
the
upper
slope
is
gradually
steepened.
Be-
yond
a
critical
angle,
empirically
determined
in
this
study
to
be
about
3°,
slope
instability
leads
to
mass
failures
and
secondary
down-slope
movement
of
sediment,
resulting
in
formation
of
the
degradational
facies
on
the
slope
and
also
in
aggradation
at
the
base
of
the
slope
of
the
bottom
set
facies,
essentially
submarine
fan
deposits.
This
model
for
shelf
margin
progradation
and
the
development
of
the
observed
seismic
facies
is
illustrated
in
Fig.
4.
Formation
of
the
foreset
and
bottomset
facies is
largely
confined
to
sea-level
lowstands,
since
during
highstands,
higher
sea
levels
create
additional
sediment
accommodation
within
shelf
depths.
In
the
offshore
Taranaki
area,
this
probably
includes
entry
of
western
South
Island
sediment
into
the
southern
Taranaki
Graben,
the
Golden
Bay/Tasman
Bay
area,
and
possibly
the
South
Wanganui
Basin.
During
these
sea
level
highstands,
the
topset
facies
is
deposited,
often
to
be
partly
eroded
during
subsequent
lowstands.
High-resolution
seismic
records
on
the
modern
shelf
reveal
that
the
topset
facies
includes
thin
sets
of
basinward-dipping
reflectors,
indicating
progradation
in
conditions
where
the
shoreline
does
not
drop
below
the
pre-existing
shelf
margin
(interpretation
of
unpublished
data
provided
by
G.P.
Thrasher).
CONTROLS
ON
SHELF
MARGIN
PROGRADATION
The
position
of
the
main
locus
of
sediment
deposition
on
a
transect
across
a
basin
margin
varies
according
to
the
inter-
play
between
three
variables:
subsidence,
eustasy,
and
sedi-
ment
supply
(e.g.
Vail,
1987).
These
parameters
are
exam-
ined
with
reference
to
the
Western
Platform
of
Taranaki
Basin
to
evaluate
their
contributions
to
the
content
and
distribution
of
the
Giant
Foresets.
Subsidence
Late
Cenozoic
subsidence
on
the
Western
Platform
and
elsewhere
in
the
Taranaki
Basin
has
been
crudely
quantified
based
on
biostratigraphic
data
from
wells,
by
Hayward
(1987)
and
Hayward
and
Wood
(1989).
Fig.
5
compiles
subsidence
curves
from
Kiwa-1
and
Witiora-1
wells,
as
examples.
Compared
to
the
adjacent
Taranaki
Graben,
the
tectonic
history
of
the
Western
Platform
is
relatively
simple,
with
localised
rifting
and
associated
rapid
subsidence
in
the
late
Cretaceous,
followed
by
waning
subsidence
during
the
early
Tertiary passive
margin
tectonic
phase
(see
also
King,
this
volume).
Renewed
rapid
subsidence
in
the
Oligocene
can
be
related
to
the
inception
of
compressive
plate
bound-
ary
stresses.
Whereas
these
late
Cretaceous
to
mid-Tertiary
subsidence
episodes
were
driven
by
tectonic
forces,
the
late
Tertiary
subsidence
of
the
Western
Platform
can
be ac-
counted
for,
within
the
limitations
of
the
method
by
which
it
has
been
derived,
by
sediment
loading
alone.
This
is
confirmed
by
the
near-horizontal
gradients
on
the
dashed
tectonic
curve
over
the
last
five
million
years
for
the
wells
in
Fig.
5.
Eustasy
The
relatively
high-frequency
oscillations
of sea
level
dur-
ing
the
Pliocene
and
Pleistocene
have
exerted
both
direct
and
indirect
control
on
rates
and
styles
of
deposition
in
the
Giant
Foresets.
Since
significant
rates
of
sediment
accumu-
lation
are
largely
restricted
to
a
narrow
belt
within
a
few
kilometres
of
the
shoreline,
shelf-margin
sedimentation
is
characteristic
of
sea-level
low
stand
intervals
when
the
shore-
line
is
close
to
the
shelf
margin.
Individual
stratal
sets
are
inferred
to
be
products
of
simple
or
closely
related
lowstand
periods.
Set
boundaries
are
usually
characterised
by
rela-
tively
high
seismic
amplitude,
which
is
believed
to
reflect
incipient
lithification
during
depositional
hiatuses
associ-
5km
202
172'
174°
173'
2500
0
SLOPE
CHANNEL
SCALE
50
0
1
KM
C)
O
2000
50
1500
0
-39°
--39'
10,00
1500
2
000
500
so
1000
1500
1000
--40
-40°
5
00
l
'so
o
.‘o
-41°-
17
1
3"
174°
172°
Fig.
2:
Structure
and
subcrop
geology
of
the
base
of
the
Pliocene
over
the
Western
Platform
(generalised
from
Thrasher
and
Cahill,
1989).
ated
with
highstands.
This
occurs
during
sedimentation
of
the
topset
facies
as
the
shoreline
progrades
across
the
previ-
ously-constructed
shelf.
In
Taranaki
Basin,
flooding
of
the
shallow,
southern
part
of
the
basin
and
the
adjacent
Wan-
ganui
Basin
during
highstands
removes
the
shoreline
200
km
or
more
from
its
lowstand
position
at
the
shelf
margin
(see
Fig.
6).
203
Sediment
supply
The
large
area
reclaimed
from
bathyal
to
shelf
depths
by
the
deposition
of
the
Giant
Foresets
is
directly
due
to
the
supply
of
a
large
volume
of
clastic
sediment.
Consideration
of
modem
rates
of
sediment
supply
to
the
continental
shelf
around
New
Zealand,
and
to
the
marine
sediment
dispersal
system
(e.g.
Carter
and
Heath,
1975;
Gibb,
1979;
Griffiths
and
Glasby,
1985)
show
that
the
west
coast
of
the
South
Island
is
the
major
source
area
for
sediments
being
deposited
into
the
southern
and
western
Taranaki
Basin
today;
it
is
likely
to
have
been
so
throughout
the
late
Cenozoic.
About
130
million
tonnes
of
suspended
sediment
is
delivered
to
the
West
Coast
shelf,
north
of
Jackson
Bay,
every
year.
This
is
an
order
of
magnitude
more
sediment
than
is
supplied
to
the
N
sea
floor
n
ra
topset
fades
progradational
foreset
facies
bottomset
fades
N
-
sea
floor
topset
fades
sea
floor
-
shelf
across
the
west
coast
of
the
North
Island
(Griffiths
and
Glasby,
1985).
The
predominance
of
waves
driven
by
west-
erly
weather
systems
onto
the
NE-SW
coastline
produces
an
effective
longshore
drift
system
which
moves
sand-grade
material
up
the
coast
at
rates
as
high
as
4500
cubic
metres
per
year
(Gibb,
1979).
Under
the
present
highstand
conditions,
that
sediment
is
dumped
into
Golden
Bay,
and
has
generated
Farewell
Spit
since
the
last
glacial
period.
However,
assum-
ing
an
analogous
drift
system
existed
during
lowstand
peri-
ods,
it
would
have
carried
the
sediment
further
north
along
the
present
outer
shelf
to
depositional
sites
across
the
shelf
margin,
producing
shelf
margin
progradation.
The
exact
locus
of
progradation
has
fluctuated
considerably,
but
upper
slope
morphology
can
be
used
to
infer
the
age
of
most
recent
progradation
(Fig.
6).
Therefore,
the
most
recent
sector
to
prograde
appears
to
be
north
of
Tangaroa-1,
where
the
upper
slope
is
smooth
(suggesting
progradational
facies
develop-
ment).
The
sector
from
about
Tangaroa-1
south
to
about
40
km
beyond
Tane-1
has
a
steep,
highly
dissected
morphol-
ogy
suggesting
active
degradation
following
a
pulse
of
pro-
gradation,
while
the
Egmont
Terrace
margin
south
and
west
of
Tane-1
has
a
gentler,
more
smoothly
dissected
character
and
may
have
been
away
from
active
deposition
for
a
longer
period.
A
3.5
kHz
seismic
profile
near
Kiwa-1
(G.P.
Thrasher,
unpublished
data)
confirms
that
at
least
during
the
last
lowstand,
the
shoreline
was
well
to
the
east
of
the
shelf
margin
in
this
area,
and
deposits
were
confined
to
the
shelf.
It
is
likely
that
fluctuations
in
degree
of
flooding
of
the
shallow
southern
Taranaki
Basin
area
and
Wanganui
Basin
have
at
least
partly
controlled
the
amount
of
sediment
delivered
to
the
shelf
margin.
For
example,
sedimentation
rates
calculated
for
the
Giant
Foresets
in
Western
Platform
wells
(averaged
over
biostratigraphic
stages)
are
as
high
as
10
cm/century
in
foreset
facies
during
the
mid-Pliocene
(late
Opoitian-Waipipian)
and
early
Pleistocene
(Nukumaruan),
but
generally
only
2-3cm/century
during
the
intervening
Mangapanean
Stage
(see
Fig.
7).
Persistence
of
marine
mudstone
facies
(Mangaweka
Mudstone)
without
interven-
ing
unconformities
in
the
central
Wanganui
Basin
(e.g.
Fleming,
1953)
indicates
that
the
basin
remained
flooded
throughout
relative
lowstands
during
the
Mangapanian,
and
N
-
sea
floor
-
_
degradational
foreset
facies
'
bottomset
facies
topset
facies
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.
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,
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:
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-;:-'.--..-E.
degradational
foreset
fades
bottomset
fad(
-
Figs
3a,
b,
c:
Characteristic
seismic
expressions
of
the
seismic
facies
defined
in
the
text.
204
x
(A)
X'
(B)
z
(C)
x'
(D)
MAP
VIEW.
X'
Topset
x
x
.
Progradational
Foreset
Slops
Failures
Bottomset
Degradational
Foreset
Fig.
4:
Model
for
the
development
of
different
seismic
facies.
the
existence
of
that
additional
sink
for
sediment
is
inferred
to
have
reduced
the
supply
to
the
Western
Platform.
In
con-
trast,
the
Wanganui
Basin
fill
is
cyclothemic
in
the
Nuku-
maruan,
for
example,
indicating
that
during
sea
level
low-
stands
the
basin
was
entirely
exposed,
providing
no
accom-
modation
for
sediments
except
during
highstand
periods.
SIGNIFICANCE
OF
GIANT
FORESETS
STUDY
FOR
PETROLEUM
EXPLORATION
This study
is
relevant
to
petroleum
exploration
for
two
reasons.
Firstly,
the
Giant
Foresets
unit
makes
up
more
than
AGE
(MY)
half
the
total
sedimentary
section
over
much
of
the
Western
Platform
area.
This
has
obviously
had
a
profound
effect
on
the
thermal
regime,
potentially
pushing
source
rocks
into
generative
conditions
in
the
last
few
million
years.
Van
der
Lingen
and
Smale
(1989)
suggest
that
this
late
loading
may
also
be
a
factor
in
porosity
preservation
in
the
Cretaceous
marine
sandstone
in
Tane-1.
Secondly,
the
depositional
style
described
in
this
paper
is
very
similar
to
that
of
the
Miocene
section
in
Taranaki,
and
to
the
thick
late
Cenozoic
sequences
in
several
other
New
Zealand
basins.
The
relationship
between
seismic
facies
and
lithology
which
can
be
documented
in
these
young
and
tectonically
undisrupted
sediments
on
the
Western
Plat-
form,
can
be
applied
to
more
complex
settings
such
as
the
Moki
Formation
(Miocene)
of
the
Taranaki
Basin,
to
better
understand
the
distribution
of
potential
reservoir
sands.
ACKNOWLEDGEMENTS
I
am
particularly
grateful
to
Glenn
Thrasher
and
June
Cahill
for
sharing
the
results
of
seismic
mapping
on
the
Western
Platform
and
elsewhere
in
Taranaki
Basin.
The
paper
has
benefitted
from
discussions
with
Bruce
Morris,
Peter
King,
Glenn
Thrasher
and
Chris
Uruski,
and
reviews
by
Brad
Field,
Chris
Uruski,
and
John
Begg.
Gael
Cuttress
drafted
most
of
the
figures.
REFERENCES
CARTER,
L.
AND
HEATH,
R.A.
1975:
Role
of
mean
circulation,
tides
and
waves
in
the
transport
of
bottom
sediment
on
the
New
Zealand
continental
shelf.
New
Zea-
land
journal
of
marine
andfreshwater
research
9:
423-448.
FLEMING,
C.A.
1953:
The
geology
of
Wanganui
Subdi-
vision.
New
Zealand
Geological
Survey
bulletin
ns
52:
362p.
GIBB,
J.
1979:
Aspects
of
beach
sediments
and
their
trans-
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along
the
New
Zealand
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-
Physical
aspects
of
coastal
problems,
Hamilton.
60
50
40
30
20
10
80
70
60
AGE
(MY)
50
40
30
20
10
L
P
S
T
0.00
A
P
S
T
W
-
-
_
0.00
\
-
-
1.00
1.00
O
ti
O
2.00
\
\\.
Paleo
sea
level
\\
Paleo
sea
level
-
2.00
Paleo
sea
bottom
Paleo
sea
bottom
-•-•--
Unit
subsidence
3.00
-
-•-
Unit
subsidence
Total
subsidence
.•
.....
•••
•••
Total
subsidence
3.00
-
Tectonic
curve
Tectonic
curve
4.00
WITIORA-1
KIWA-1
Fig.
5:
Subsidence
and
tectonic
curves
for
Kiwa-1
and
Witiora-1,
from
Hayward
and
Wood
(1989).
205
38°S-
—38°S
zs
—39°S
39°S
+Taimana-1
+Witiora-1
Tane-1
NEW
PLYMOUTH
NORTH
—41°S
ac
0
172°E
173°E
174°E
175°E
50
0
1
0
M
Tua
Tua-1
y
O
/
Tangaroa
Ariki-1
-
TASMAN
300
SEA
Kora-1
050
500
0
ISLAND
Maui-A
EGMONT
TERRACE
K
wa-
40°S
450
00
Maui-4
Te
Whatu
2
2
0
1
5
0
Cook-1
O
O
rj
.0
4
,,beb
ISLAND
(,‘
((‘
N
°
t
e
S~
e'
/
SOUTH
SOUTH
172°E 173°E
I/
NELSON
ISLAND
Fig.
6:
Modern
bathymetry
of
offshore
Taranaki,
approximate
position
of
the
west
-facing
shoreline
during
late
Quaternary
sea-level
low
stands,
and
(inset)
aspects
of
the
sediment
supply
and
distribution
systems
inferred
to
have
operated
during
low
stand
intervals.
206
Age
(millions
of
years)
30
20
We
Wq
Age
(millions
of
years)
5.0
d
i
))
30
2.0
rrk
eWo
IWo
Wp
Wm
eWn
IWn
eW0
IWo
Wp
Wm
I
eWn
IWn
10
We
Wq
2.
KIWA-1
Sedimentation
rate
(cm/1
00yrs)
-2000
<0.1
-1000
Fig.
7:
Sedimentation
rate
based
.,11
biostratigraphic
data
from
Wainui-1
and
Kiwa-1
wells,
Western
Platform.
Data
from
Hayward
(1984)
and
Hayward
(1985).
nal
e
ft
s
mop
q
(w)
ig
dea
a
am
g
-
I
GRIFFITHS
,
G.A.
AND
GLASBY,
G.P.
1985:
Input
of
river-derived
sediment
to
the
New
Zealand
continental
shelf:
I
Mass.
Estuarine,
coastal
and
shelf
science
21:
773-787.
HAYWARD,
B.W.
1984:
Foraminiferal
biostratigraphy
of
Wainui-1
offshore
well,
west
Taranaki.
New
Zealand
Geo-
logical
Survey
report
Pal
83:
24p.
HAYWARD,
B.W.
1985:
Foraminiferal
biostratigraphy
of
Kiwa-1
offshore
well,
south
Taranaki
Basin.
New
Zealand
Geological
Survey
report
Pal
96:
35p.
HAYWARD,
B.W.
1987:
Paleobathymetry
and
structural
and
tectonic
history
of
Cenozoic
drillhole
sequences
in
Taranaki
Basin.
New
Zealand
Geological
Survey
report
Pal
122:
63p.
HAYWARD,
B.W.
&
WOOD,
R.A.
1989:
Computer-gen-
erated
geohistory
plots
for
Taranaki
drillhole
sequences.
New
Zealand
Geological
Survey
report
Pal
147:
73p.
KING,
P.R.
1990:
Polyphase
development
of
the
Taranaki
Basin,
New
Zealand,
New
Zealand:
changes
in
sedimentary
and
structural
style.
1989
New
Zealand
Oil
Exploration
Conference
Proceedings
(This
volume).
Ministry
of
Com-
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SHELL
BP&
TODD
OIL
SERVICES
LTD.
1977:
Well
resume.
Tane-1
(offshore)
PPL
38007,
sub-area
of
Traanaki,
New
Zealand.
New
Zealand
Geological
Survey
unpub-
lished
open-file
petroleum
report
no.
698.
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G.P.
&
CAHILL,
J.P.
1989:
S
ubsurface
maps
of
the
Taranaki
Basin,
New
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New
Zealand
Geologi-
cal
Survey
report
G142.
VAIL,
P.R.
1987:
Seismic
stratigraphy
interpretation
using
Sequence
Stratigraphy
Part
I:
Seismic
stratigraphy
interpre-
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in
Bally,
A.W.
(editor)
AAPG
Atlas
of
Seismic
Stratigraphy.
MPG
Studies
in
Geology
No.
27,
volume
1:
1-10.
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DER
LINGEN,
G.J.
AND
S
MALE,
D.
1990:
Porosity
evaluation
of
an
Upper
Cretaceous
marine
sandstone
in
Tane-1:
offshore
oil
exploration
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Taranaki
Basin,
New
Zealand.
Proceedings
of
the
1989
New
Zealand
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ration
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WALCOTT,
R.I.
1978:
Present
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52:
137-164.
WAINUI-1
Sedimentation
rate
(cm/1
00yrs)
0
207