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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 298 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 299 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 300 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 301 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 302 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 303 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 304 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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, Proceeding of Indonesian st Petroleoum Association 1 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, Proceeding of Indonesian Petroleoum Association 2nd Annual Convention, p. 105 – 108 Bramlette, M.N. & Wilcoxon, J.A. (1967), Middle Tertiary Calcareous Nannoplankton of the Cipero Section, Trinidad, W.I., in Haq, Bilal U., 1984, Nannofossils Biostratigraphy (Benchmark Papers in Geology/78), Hutchinson Ross Publishing Company, Pennsylvania, p. 71-113 Stroundsburg, 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, Geological Research and Development Centre, Bandung 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 Okada, H. & Bukry, D. (1980), Supplementary Modification and Introduction of Code Numbers to the Low Latitude Coccolith Biostratigraphic Zonation (Bukry, 1973; 1975), Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 305 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 306 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 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 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 307 Seminar Nasional Fakultas Teknik Geologi, Bandung 24 Mei 2014 Geologi Untuk Meningkatkan Kesejahteraan Masyarakat 308