Full Paper - Seminar FTG

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Full Paper - Seminar FTG
Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014
Middle Miocene to Early Pliocene Nannofossil Biostratigraphy
on Jatiluhur area, Bogor Through, Indonesia
Isnaniawardhani, V., Sunardi, E.
Faculty of Geology, Padjadjaran University
Jl. Raya Bandung-Sumedang Km. 21, Jatinangor Sumedang
Email: vijaya_i@unpad.ac.id, edy_sunardi@unpad.ac.id
ABSTRACT
Nannofossil biostratigraphy is studied on several sections in Jatiluhur area. Upper Cibulakan,
Parigi and Cisubuh Formations dated Miocene-Pliocene are well exposed near Jatiluhur reservoir
and along river-side clifts of the Ciherang, Cikeo, Cigajah, Cisaray, Cikekep, Cibinbin and Cigaruguy
rivers. Biostratigraphy framework is provided by the bioevents of nannofossil marker species.
The five markers have been selected; among all: Sphenolithus heteromorphus, Catinaster
coalitus, Discoaster hamatus, Discoaster quinqueramus and Ceratolithus rugosus.
On the basis of first appearance (FA) and last appearance (LA) of marker species, three range
zone and four interval zones are established. By starting from the oldest, those are: Sphenolithus
heteromorphus partial-range zone (not younger than NN5 or CN4 zone, Middle Miocene aged or
not younger than 13 my before present), Sphenolithus heteromorphus – Catinaster coalitus
interval zone (NN6 – NN7 or CN5 zones, Middle Miocene aged or 13 - 12 Ma), Catinaster coalitus
– Discoaster hamatus interval zone (NN8 or CN6 zone, Middle Miocene aged or 12 Ma),
Discoaster hamatus – Discoaster quinqueramus interval zone (NN9 – NN10 or CN7 zones, Middle
to Late Miocene aged or 12 - 9.3 Ma), Discoaster quinqueramus total-range zone (NN11 or CN9
zone, Late Miocene aged or 9.3 – 5.7 Ma), Discoaster quinqueramus – Ceratolithus rugosus
interval zone (NN12 or CN10 zone, Early Pliocene aged or 5.7 – 4.5 Ma), and Ceratolithus rugosus
partial-range zone (NN13 or CN10 zone, Early Pliocene aged or not older than 4.5 Ma).
The nannofossil biostratigraphy at Jatiluhur sections well-dated the Middle Miocene to Early
Pliocene sedimentary succession of 14.4 Ma to 3.2 Ma. Miocene-Pliocene boundary is welldeterminated by last appearance of Discoaster quinqueramus (5.7 Ma) and significant events (as
marked by species extinctions, abundancy and diversity changes). These biostratigraphic zones
be useful for inter and intra basinal correlations.
Keywods: nannofossil, biostratigraphy, Miocene, Pliocene, zon
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ABSTRAK
Biostratigrafi nannofosil dipelajari pada beberapa lintasan di daerah Jatiluhur. Formasi-formasi
Cibulakan Atas, Parigi dan Cisubuh berumur Miosen - Pliosen tersingkap baik dekat bendungan
Jatiluhur, sepanjang tebing sungai Ciherang, Cikeo, Cigajah, Cisaray, Cikekep, Cibinbin dan
Cigaruguy. Kerangka biostratigrafi dikenali dari bioeven spesies-spesies petunjuk nannofosil.
Lima fosil petunjuk telah dipilih, yaitu: Sphenolithus heteromorphus, Catinaster coalitus,
Discoaster hamatus, Discoaster quinqueramus dan Ceratolithus rugosus.
Berdasarkan pemunculan awal dan pemunculan akhir (kepunahan) dari spesies petunjuk, disusun
tiga zona kisaran dan empat zona selang. Mulai dari yang paling tua, zona tersebut adalah: zona
kisaran Sphenolithus heteromorphus (tidak lebih muda dari NN5 atau CN4, berumur Miocene
Tengah atau tidak lebih tua dari 13 juta tahun lalu), zona selang Sphenolithus heteromorphus –
Catinaster coalitus (zone NN6 – NN7 atau CN5, berumur Miosen Tengah atau 13 - 12 jtl), zona
selang Catinaster coalitus – Discoaster hamatus (zona NN8 or CN6, berumur Miosen Tengah atau
12 jtl), zona selang Discoaster hamatus – Discoaster quinqueramus (zona NN9 – NN10 atau CN7,
berumur Miosen Tengah hingga Akhir atau 12 - 9,3 jtl), zona kisaran Discoaster quinqueramus
(zona NN11 atau CN9, berumur Miosen Akhir atau 9,3 - 5,7 jtl), zona selang Discoaster
quinqueramus – Ceratolithus rugosus (zona NN12 atau CN10, Pliosen Awal atau 5,7 – 4,5 jtl), dan
zona kisaran Ceratolithus rugosus (zona NN13 atau CN10, Pliosen Awal atau tidak lebih tua dari
4,5 jtl).
Biostratigrafi nannofosil pada lintasan-lintasan Jatiluhur menentukan umur suksesi sedimen
Miosen Tengah hingga Pliosen Awal yang berkisar 14,4 hingga 3,2 juta tahun lalu. Batas MiosenPliosen dapat dikenali dengan baik dari pemunculan akhir Discoaster quinqueramus (5,7 jtl) dan
even-even yang ditandai oleh kepunahan-kepunahan spesies, perubahan kelimpahan dan
keanekaragaman. Zona-zona biostratigrafi ini akan sangat berguna untuk korelasi dalam dan
antar cekungan.
Kata kunci: nannofossil, biostratigrafi, Miosen, Pliosen, zona
INTRODUCTION
Since the stratigraphic significance of
discoaster, coccolith and related form,
commonly referred to as the nannofossils,
first become apparent (Bramlette & Reidel,
1954 in Martini, 1971), much work has been
done to describe the many assemblages found
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in marine sediment from the Jurassic,
Cretaceous, Tertiary and Quaternary all over
the word.
Cenozoic
planktonic
nannofossils
(nannoplankton) biostratigraphy zone have
been studied by Hays, et al (1967), Bramlette
& Wilcoxon (1967), Martini (1971), Bukry
(1973) and Okada & Bukry (1980). Martini’s
standard nannofossil biozonation using
samples throughtout the word is the most
popular to be used in Indonesia. The 25
nannoplankton zones in the Paleogene
(numbered NP.1 to NP.25) and the 21
nannoplankton zones in the Neogene to
Quaternary (numbered NN1 to NN21) are
supposed for a standard Tertiary and
Quaternary calcareous zonation. Whereas
Okada & Bukry (1980) suggested 19
calcareous nannoplankton zones in the
Paleogene (numbered CP1 to CP19) and 15
calcareous nannoplankton zones in Neogene
which are divided into several subzones.
Nannofossils are commonly used for
determining age and correlations for oil
exploration; but it not much has been
published on the calcareous biostratigraphy in
Indonesia. In Bogor Through, a lot of sections
on marine sedimentary can be used to study
of biostratigraphy. That is why the study of
nannofossil biostratigraphy was to be
conducted in Jatiluhur sections in Bogor
Through (Figure 1). This study aims to
establish nannofossil biostratigraphic zone
based on the first appearance and last
appearance of marker species which can be
observed in study area.
For purpose of establishing level of inter and
intra basinal correlation, biostratigraphic zone
was determinated based on the first
appearance and last appearance of marker
species be coincided with many previous
studies.
MATERIALS AND METHODS
Collecting secondary data, included regional
geology data, was conducted to plan the
several observe sections on Jatiluhur area.
Field data record and marine sediment
samples were taken from outcrops near
Jatiluhur reservoir and along of Ciherang,
Cikeo, Cigajah, Cisaray, Cikekep, Cibinbin and
Cigaruguy rivers. In laboratory, samples were
prepared using smear slides methods and
determinated under a polarized microscrope
at x 1000 magnification in both cross polarized
and phase light. Identification of the
nannofossils refers to Bramlette & Wilcoxon
(1967) and Perch-Nielsen (1985). The wellpreserved nannofossils assemblages in
sediments were determinated quantitatively.
Some nannofossils marker species are
selected based on criterias that distinctive,
easy identified, and have widely geographic
distribution. The first appearance and last
appearance of the marker spesies was marked
as bioevents. Biostratigraphic zone were
establish based on these events. Other
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species extinction events, abundancy and
diversity index was recorded to support the
interpretation.
RESULT AND DISCUSSIONS
1. Geology of Jatiluhur area
The geology and stratigraphy of Jatiluhur area
have been dealt elsewhere (eg. Van
Bemmelen, 1949; Marks, 1957; Bauman et al.,
1972; Sudjatmiko, 1972; Arpandi &
Patmosukismo, 1975; Effendy, 1986; and
Martodjojo, 2003). Successions of marine
sediment is perhaps containing nannofossils
commencing the Upper Cibulakan, Parigi and
Cisubuh Formations. The basal of Upper
Cibulakan is primarily composed by
intercalated marine claystone and shale,
interbedded with limestone and sandstone.
The Parigi Formation conformably overlies the
Upper Cibukan Formations, and is dominated
by detritus and reefal limestone intervals. The
Cisubuh Formation consist of marine
claystone, sandstone and limestone. This
formation becomes more sandy upsection
with intercalated coal beds. Figure 2 show
lithological distributions according to geologic
data record and citra landsat interpretation in
study area.
coalitus, Discoaster hamatus, Discoaster
quinqueramus and Ceratolithus rugosus.
Systematic description of these markers refers
to Perch-Nielsen (1985) and Bramlette &
Wilcoson (1967) are as follow:
Genus Ceratolithus, Kamptner, 1950
Ceratolithus rugosus Bukry & Bramlette
This spesies forms the horseshoe-shaped
coccoliths which show birefringence between
crossed nicols, has no such apical spine. It is a
robust form with horns that are parallel for
most of their length. It usually heavily
calcified, but sometimes the rows of nodes on
the horns can be seen.
Genus Discoaster, Tan, 1927
Discoaster hamatus Martini & Bramlette
This species is large, 5-armed form with small
knob in the centre. This arms are long,
somewhat curved, and turn sharply clockwise
and downward near the end, as viewed on the
convex side. A much smaller knob is usual as a
bifurcation, although it appears to be
continuation of the main part of the arm as it
extends in the same direction.
Discoaster quinqueramus Gartner
2. Marker Species
On samples collected in Jatiluhur sections, five
markers species have been selected; among
all: Sphenolithus heteromorphus, Catinaster
This species has 5 tapering, long non
bifurcating arms arraged symmetrically and
robust central area with very prominent, 5armed central knob.
Genus Sphenolithus, Deflandre, 1952
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Spenolithus heteromorphus Deflandre
This species has a more compact proximal
shield and column, where the columb and the
lateral element are about equal in height. It is
formed by the basal quadrant instead of by
the
apical
complex.
Spenolithus
heteromorphus looks like a butterfly when
seen between crossed nicols at 00 and has a
very bright apical spine at 450 (Perch-Nielsen,
1985). The appearance between crossed nicol
is characteristic, parallel to and at 450 to the
nicols. Study at various orientations in a
viscous medium shows that a series of eight or
nine spines surround the depressed basal area
lacking spines, with radiating shorter spines
above producing the black cross between
crossed nicols when the single big apical spine
is at extinction position. This apical spine
varies markedly in lengthband robustness
(Bramlette & Wilcoxon, 1967).
Genera Incertae Sedis
Catinaster coalitus Martini & Bramlette
Catinaster is relatively large (more than
Discoasters), basket-shaped central part. This
species is small, nearly circular, the 6 rays do
not extend beyond.
3. Biostratigraphyc Zonations
Based on the first appearance (FA) and last
appearance (LA) of marker species, three
range zone and four interval zones were
established.
a) Sphenolithus heteromorphus partialrange zone
Definition: The appearance of
relatively
common
Sphenolithus
heteromorphus, Discoaster deflandrei,
and Calcidiscus forms defines this zone
Age: Middle Miocene or not younger
than 13 my before present
Correlation:
Sphenolithus
heteromorphus zone (CN4) of Okada &
Bukry (1980), does not correlate
exactly with NN5 zone of Martini
(1971) or Sphenolithus heteromorphus
zone Of Perch-Nielsen (1986)
Remark: Okada & Bukry (1980) used
the last appearance of Sphenolithus
heteromorphus to define the base of
CN4 of their zonal scheme.
b) Sphenolithus
heteromorphus
–
Catinaster coalitus interval zone
Definition: Interval from the last
appearance
of
Sphenolithus
heteromorphus to the first appearance
of Catinaster coalitus
Age: Middle Miocene or 13 to 12 Ma
Correlation: Coccolithus miopelagicus
subzone (CN5a) and Discoaster kugleri
subzone (CN5b) of Okada & Bukry
(1980), correlate with NN6 – NN7 zone
of Martini (1971); Discoaster exilis
zone and Discoaster kugleri zone of
Perch-Nielsen (1986) as well
c) Catinaster coalitus –
hamatus interval zone
Discoaster
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Definition: Interval from the first
appearance of Catinaster coalitus to
the first appearance of Discoaster
hamatus
Age: Middle Miocene or 12 Ma
Correlation: Catinaster coalithus zone
(CN6) of Okada & Bukry (1980) and
Perch-Nielsen (1980), middle part of
the Discoaster variabilis zone (NN6) of
Martini (1971) as well
Remark: Okada & Bukry (1980) used
the first appearance of Catinaster
coalitus to defined the base of CN6 of
their zonal scheme.
d) Discoaster hamatus – Discoaster
quinqueramus interval zone
Definition: Interval from the first
appearance of Discoaster hamatus to
the first appearance of Discoaster
quinqueramus
Age: Middle to Late Miocene or 12 to
9.3 Ma
Correlation: Discoaster hamatus zone
(CN7) and Discoaster neohamatus
zone (CN8) of Okada & Bukry (1980),
middle part of Discoaster variabilis
zone (NN6) of Martini (1971),
Discoaster hamatus zone and
Discoaster calcaris zone of PerchNielsen (1986) as well
Remark: Okada & Bukry (1980) used
the first appearance of Discoaster
hamatus to define the base of CN7 of
their zonal scheme.
e) Discoaster quinqueramus total-range
zone
Definition: The first appearance to last
appearance
of
Discoaster
quinqueramus
Age: Late Miocene or 9.3 – 5.7 Ma
Correlation: Discoaster quinqueramus
zone of Martini, 1971 (NN11), Okada &
Bukry, 1980 (CN9), and Perch-Nielsen
(1970)
Remarks: Martini (1970) used the first
appearance
of
Discoaster
quinqueramus to define the base of
NN11 of his zonal scheme. The first
appearance of Discoaster berggrenii
and/or Discoaster surculus to last
appearance
of
Discoaster
quinqueramus is used by Okada &
Bukry to defines their zone.
f) Discoaster
quinqueramus
–
Ceratolithus rugosus interval zone
Definition: Interval from the last
appearance
of
Discoaster
quinqueramus to the first appearance
of Ceratolithus rugosus
Age: Early Pliocene or 5.7 – 4.5 Ma
Correlation: lower and middle subzone
of Amaurolithus tricorniculatus zone
(CN10) of Okada & Bukry (1980), NN12
zone of Martini (1971)
g) Ceratolithus rugosus partial-range
zone
Definition: The appearance of
Ceratolithus rugosus associated with
rare Discoaster asymmetricus and D.
pentaradiatus
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Age: Early Pliocene (Zanclean) or 5.7
Ma – 4.5 Ma
Correlation: Ceratolithus rugosus
subzone (CN10 c) of Okada & Bukry,
1980 (CN10) and Perch-Nielsen (1986),
NN13 zone of Martini (1971).
4. Discussions
3.
Middle Miocene to Early Pliocene
nannofossils biostratigraphy on Jatiluhur area
correlated to proposed standard nannofossils
zonation. These zones recognized in this study
correlated with zones of Martini (1971),
Okada & Bukry (1980) and Perch-Nielsen
(1986). The detail biostratigraphic zonation
indicated that throughout Middle Miocene to
Early Pliocene interval (14.4 to 3.2 Ma), it
provides a high resolution biostratigraphy.
Miocene-Pliocene
boundary
is
welldeterminated by last appearance of
Discoaster quinqueramus (5.7 Ma) and
significant events as marked by species
extinctions, abundancy and diversity changes.
CONCLUSIONS
1.
2.
Upper Cibulakan, Parigi and Cisubuh
Formations dated Miocene-Pliocene that
are well exposed near Jatiluhur reservoir
and along river-side clifts of the Ciherang,
Cikeo, Cigajah, Cisaray, Cikekep, Cibinbin
and
Cigaruguy
rivers
contains
nannofossils
The five nannofossil species have been
selected as bioevent markers to provide
biostratigraphic framework in this area;
among all:
a) Ceratolithus rugosus Bukry &
Bramlette,
b) Discoaster hamatus Martini &
Bramlette,
c) Discoaster quinqueramus Gartner,
d) Spenolithus
heteromorphus
Deflandre, and
e) Catinaster coalitus Martini &
Bramlette.
Three range zones and four interval zones
are established based on first appearance
(FA) and last appearance (LA) of marker
species. By starting from the oldest, those
are:
a) Sphenolithus
heteromorphus
partial-range zone (not younger
than NN5 or CN4 zone, Middle
Miocene aged or not younger than
13 my before present),
b) Sphenolithus heteromorphus –
Catinaster coalitus interval zone
(NN6 – NN7 or CN5 zones, Middle
Miocene aged or 13 - 12 Ma),
c) Catinaster coalitus – Discoaster
hamatus interval zone (NN8 or
CN6 zone, Middle Miocene aged or
12 Ma),
d) Discoaster hamatus – Discoaster
quinqueramus interval zone (NN9
– NN10 or CN7 zones, Middle to
Late Miocene aged or 12 - 9.3 Ma),
e) Discoaster quinqueramus totalrange zone (NN11 or CN9 zone,
Late Miocene aged or 9.3 – 5.7
Ma),
f) Discoaster
quinqueramus
–
Ceratolithus rugosus interval zone
(NN12 or CN10 zone, Early
Pliocene aged or 5.7 – 4.5 Ma), and
g) Ceratolithus rugosus partial-range
zone (NN13 or CN10 zone, Early
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4.
Pliocene aged or not older than 4.5
Ma).
Miocene-Pliocene boundary is welldeterminated by last appearance of
Discoaster quinqueramus (5.7 Ma) and
significant events as marked by species
extinctions, abundancy and diversity
changes.
REFERENCES
Arpandi, D. & Patmosukismo, S.
(1975), The Cibulakan Formation as One of the
Most Prospective Stratigraphic Units in the
North-West Java Basinal Area, Proceeding of
Indonesian Petroleoum Association 4th Annual
Convention, p. 181 – 204
Bauman, P., Oesterle, H., Suminta,
Wibisono (1972), The Cenozoic of Java and
Sumatera,
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Petroleoum
Association
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Annual
Convention, p. 31 – 40
Bauman, P., De Genevraye, P., Samuel,
L., Mudjito, Sajekti, S. (1973), Contribution to
the Geological Knowledge of South West Java,
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Bramlette, M.N. & Wilcoxon, J.A.
(1967),
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Pennsylvania, p. 71-113
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Bukry, D. (1973), Low Latitude
Coccolith Biostratigraphic Zonation, Initial
Report of the Deep Sea Driling Project,
Volume 15, p. 685-695, 701-703
Effendi, A.C (1986), Geological Map of
Bogor Quadrange, West Java, scale 1:100.000,
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Hay, W.W., Mohler, H.P., Roth, P.H.,
Schmidt, R.R. & Boudreaux, J.E. (1967),
Calcareous Nannoplankton Zonation of the
Cenozoic of the Gulf Coast and CaribbeanAntillean Area and Transoceanic Correlation,
Gulf Coast Assoc. Geol. Socs. Trans, Volume
17, p. 428 – 459
Mark, P. (1957), Stratigraphic Lexicon
of Indonesia, Scientific Publication no. 31,
Geological Directorate, Bandung
Martini, E (1971), Standard Tertiary
and Quaternary Calcareous Nannoplankton
Zonation, Proceedings of The II Planktonic
Conference, Roma, 1970, A. Farinacci, ed.
Ediziioni Tecnoscienza, Rome, p. 739 – 785
Martodjojo, S. (2003), Evolusi
Cekungan Bogor, Penerbit ITB, 239 p
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Marine Micropaleontology, Volume 5, p. 321
– 325
Perch-Nielsen, K., (1985), Cenozoic
Calcareous Nannofossils in Bolli, H.M.,
Saunders, J.B., and Perch-Nielsen, K., eds
(1986), Plankton Stratigraphy, Cambridge
University Press, p. 427 – 544
Sudjatmiko (1972), Geological Map of
the Cianjur Quadrange scale 1:100.000,
Geological Survey of Indonesia, Bandung
Van Bemmelen, R.W. (1949), The
Geology of Indonesia, Martinus Nijhoff, The
Hague
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Figure 1. The study area occupies Jatiluhur area, Bogor Through
Figure 2. Geological Map (modified from Sudjatmiko, 1972; Effendi, 1986)
and Citra Landsat Imaginery Interpretation of Jatiluhur area showing stratigraphic units
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