University of Wollongong Research Online Faculty of Science, Medicine and Health - Papers: Faculty of Science, Medicine and Health part A 2017 Relative sea-level change in western New Guinea recorded by regional biostratigraphic data David P. Gold Royal Holloway University of London Lloyd T. White University of Wollongong, [email protected] Indra Gunawan Bandung Institute of Technology Marcelle BouDagher Fadel University College London Publication Details Gold, D. P., White, L. T., Gunawan, I. & BouDagher-Fadel, M. K. (2017). Relative sea-level change in western New Guinea recorded by regional biostratigraphic data. Marine and Petroleum Geology, 86 1133-1158. Research Online is the open access institutional repository for the University of Wollongong. For further information contact the UOW Library: [email protected] Relative sea-level change in western New Guinea recorded by regional biostratigraphic data Abstract We present new biostratigraphic analyses of approximately 200 outcrop samples and review biostratigraphic data from 136 public domain exploration wells across western New Guinea. Biostratigraphic ages and palaeodepositional environments were interpreted from occurrences of planktonic and larger benthic foraminifera, together with other fossils and environmental indicators where possible. These data were compared with existing geological maps and exploration well data to reconstruct the palaeogeography of western New Guinea from the Carboniferous to present day. In addition, we used the known bathyal preferences of fossils to generate a regional sea-level curve and compared this with global records of sea-level change over the same period. Our analyses of the biostratigraphic data identified two major transgressive- regressive cycles in regional relative sea-level, with the highest sea levels recorded during the Late Cretaceous and Late Miocene and terrestrial deposition prevalent across much of western New Guinea during the Late Paleozoic and Early Mesozoic. An increase in the abundance of carinate planktonic foraminifera indicates a subsequent phase of relative sea-level rise during a regional transgressive event between the Late Jurassic and Late Cretaceous. However, sea-levels dropped once more during a regressive event between the Late Cretaceous and the Paleogene. This resulted in widespread shallow water carbonate platform development in the Middle to Late Eocene. A minor transgressive event occurred during the Oligocene, but this ceased in the Early Miocene, likely due to the collision of the Australian continent with intra-Pacific island arcs. This Miocene collision event resulted in widespread uplift that is marked by a regional unconformity. Carbonate deposition continued in platforms that developed in shallow marine settings until these were drowned during another transgressive event in the Middle Miocene. This transgression reached its peak in the Late Miocene and was followed by a further regression culminating in the present day topographic expression of western New Guinea. Disciplines Medicine and Health Sciences | Social and Behavioral Sciences Publication Details Gold, D. P., White, L. T., Gunawan, I. & BouDagher-Fadel, M. K. (2017). Relative sea-level change in western New Guinea recorded by regional biostratigraphic data. Marine and Petroleum Geology, 86 1133-1158. This journal article is available at Research Online: http://ro.uow.edu.au/smhpapers/4825 Accepted Manuscript Relative sea-level change in western New Guinea recorded by regional biostratigraphic data D.P. Gold, L.T. White, I. Gunawan, M. BouDagher-Fadel PII: S0264-8172(17)30271-4 DOI: 10.1016/j.marpetgeo.2017.07.016 Reference: JMPG 2998 To appear in: Marine and Petroleum Geology Received Date: 8 June 2017 Revised Date: 0264-8172 0264-8172 Accepted Date: 17 July 2017 Please cite this article as: Gold, D.P., White, L.T., Gunawan, I., BouDagher-Fadel, M., Relative sea- level change in western New Guinea recorded by regional biostratigraphic data, Marine and Petroleum Geology (2017), doi: 10.1016/j.marpetgeo.2017.07.016. This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain. ACCEPTED MANUSCRIPT 1 Relative sea-level change in western New Guinea recorded by regional 2 biostratigraphic data 3 D. P. Gold 1*, L. T. White 1,2, I. Gunawan 1,3, M. BouDagher-Fadel 4 4 5 1. Southeast Asia Research Group, Department of Earth Sciences, Royal Holloway University 6 of London, Egham, Surrey, TW20 0EX 7 2. School of Earth and Environmental Sciences, University of Wollongong, Wollongong, NSW, 8 2522, Australia 9 3. Institut Teknologi Bandung, Jl. Ganesha No.10, Lb. Siliwangi, Coblong, Kota Bandung, Jawa 10 Barat 40132, Indonesia 11 4. Department of Earth Sciences, University College London, Gower Street, London, WC1E 12 6BT, UK 13 14 *Corresponding author: David Gold ([email protected]) 15 16 17 18 19 20 21 22 ACCEPTED 23 24 25 26 1 ACCEPTED MANUSCRIPT 27 Abstract 28 We present new biostratigraphic analyses of approximately 200 outcrop samples 29 and review biostratigraphic data from 136 public domain exploration wells across 30 western New Guinea. Biostratigraphic ages and palaeodepositional environments 31 were interpreted from occurrences of planktonic and larger benthic foraminifera, 32 together with other fossils and environmental indicators where possible. These data 33 were compared with existing geological maps and exploration well data to 34 reconstruct the palaeogeography of western New Guinea from the Carboniferous to 35 present day. In addition, we used the known bathyal preferences of fossils to 36 generate a regional sea-level curve and compared this with global records of sea- 37 level change over the same period. Our analyses of the biostratigraphic data 38 identified two major transgressive-regressive cycles in regional relative sea-level, 39 with the highest sea levels recorded during the Late Cretaceous and Late Miocene 40 and terrestrial deposition prevalent across muchMANUSCRIPT of western New Guinea during the 41 Late Paleozoic and Early Mesozoic. An increase in the abundance of carinate 42 planktonic foraminifera indicates a subsequent phase of relative sea-level rise during 43 a regional transgressive event between the Late Jurassic and Late Cretaceous. 44 However, sea-levels dropped once more during a regressive event between the Late 45 Cretaceous and the Paleogene. This resulted in widespread shallow water carbonate 46 platform development in the Middle to Late Eocene. A minor transgressive event 47 occurred duringACCEPTED the Oligocene, but this ceased in the Early Miocene, likely due to the 48 collision of the Australian continent with intra-Pacific island arcs. This Miocene 49 collision event resulted in widespread uplift that is marked by a regional 50 unconformity. Carbonate deposition continued in platforms that developed in shallow 51 marine settings until these were drowned during another transgressive event in the 2 ACCEPTED MANUSCRIPT 52 Middle Miocene. This transgression reached its peak in the Late Miocene and was 53 followed by a further regression culminating in the present day topographic 54 expression of western New Guinea. 55 56 Keywords: Tectonics; foraminifera; palaeogeography; biogeography; eustasy; 57 58 1. Introduction 59 New Guinea has represented the northernmost boundary of the Australian Plate 60 from the present until at least the Permian (perhaps as early as the Carboniferous). 61 During this time New Guinea was part of an Andean-style continental arc system that 62 extended around a large portion of Gondwana (Charlton, 2001; Hall 2002; 2012; Hill 63 and Hall 2003; Crowhurst et al., 2004; Metcalfe 1998; 2009; Gunawan et al., 2012; 64 2014; Webb and White, 2016). This long-livedMANUSCRIPT plate boundary records evidence of 65 numerous tectono-thermal events during the Paleozoic, Mesozoic and Cenozoic 66 (e.g. Visser and Hermes, 1962; Pieters et al., 1983; Davies and Jaques 1984; 67 Pigram and Davies 1987; Pigram and Symonds 1991; Baldwin and Ireland 1995; 68 Baldwin et al., 2004; 2012; Davies, 2012; Bailly et al., 2009; Holm and Richards, 69 2013; Holm et al., 2015; 2016; François et al., 2016). However, much of the geology 70 of New Guinea is also dominated by siliciclastic and carbonate deposition during 71 seemingly long periods of quiescence (Pieters et al., 1983; Pigram; Visser and 72 Hermes, 1962;ACCEPTED Fraser et al., 1993; Hill, 1991; Davies, 2012; Baldwin et al., 2012). 73 We focus on the age and depositional environment of these sediments in western 74 New Guinea, an area that is relatively underexplored, with the last major geological 75 mapping campaign being conducted in the 1980’s (e.g. Masria et al., 1981; Pieters et 76 al., 1983; Dow et al., 1986; Atmawinata et al., 1989; Pieters et al., 1989; Dow et al., 3 ACCEPTED MANUSCRIPT 77 1990; Harahap et al., 1990; Pieters et al., 1990; Robinson et al., 1990; Panggabean 78 et al., 1995). We present new biostratigraphic age data based on benthic and 79 planktonic foraminifera, as well as facies analyses from nearly 200 outcrop samples 80 from western New Guinea. Where possible, we compared these results with