VICTORIAN GAS PROGRAM New micropalaeontological results from legacy core Onshore Otway Basin, Victoria
S. Gallagher & F. Stanislaus Victorian Gas Program Technical Report 8 September 2019 Authorised by the Director, Geological Survey of Victoria Department of Jobs, Precincts and Regions 1 Spring Street Melbourne Victoria 3000 Telephone (03) 9651 9999
© Copyright State of Victoria, 2019.
Department of Jobs, Precincts and Regions 2019
Except for any logos, emblems, trademarks, artwork and photography this work is made available under the terms of the Creative Commons Attribution 3.0 Australia licence. To view a copy of this licence, visit creativecommons.org/licenses/by/3.0/au. It is a condition of this Creative Commons Attribution 3.0 Licence that you must give credit to the original author who is the State of Victoria.
This document is also available in an accessible format at www.djpr.vic.gov.au
Bibliographic reference GALLAGHER, S. & STANISLAUS, F., 2019. New micropalaeontological results from legacy core, Onshore Otway Basin, Victoria. Victorian Gas Program Technical Report 8. Geological Survey of Victoria. Department of Jobs, Precincts and Regions. Melbourne, Victoria. 30p.
ISBN 978-1-76090-195-0
Geological Survey of Victoria Catalogue Record 160054
Key Words biostratigraphy, Cenozoic, Late Cretaceous, micropalaeontology, Otway Basin
Acknowledgements Sample selection was carried out by S. Gallagher and F. Stanislaus at the Geological Survey of Victoria Drill Core Library in Werribee. All sample preparation and micropalaeontological analysis was undertaken at The University of Melbourne by S. Gallagher and F. Stanislaus, who also wrote and compiled the text. Roy France and Louise Goldie Divko of the Geological Survey of Victoria reviewed and edited the text. Luong Tran compiled the maps and Allyson Crimp designed the final report.
About the Victorian Gas Program The Victorian Gas Program (VGP) is a comprehensive science-led program, incorporating geoscientific and environmental research to assess the risks, benefits and impacts of potential onshore conventional gas exploration and production.
The program is also investigating the potential for further discoveries of onshore conventional and offshore gas in the Otway and Gippsland geological basins and assessing the feasibility of additional onshore underground gas storage in depleted reservoirs around the Port Campbell area.
The VGP includes an extensive, proactive and phased community and stakeholder engagement program, through which the results of the scientific studies are being communicated.
About the Geological Survey of Victoria The Geological Survey of Victoria (GSV) is the Victorian Government’s geoscience agency and sits within the Department of Jobs, Precincts and Regions.
GSV provides evidence-based knowledge and information to Government, industry, academia and the community, on Victoria’s earth resources, using the latest geoscience technologies and methods.
For more details visit earthresources.vic.gov.au/gsv
Disclaimer This publication may be of assistance to you, but the State of Victoria and its employees do not guarantee that the publication is without flaw of any kind or is wholly appropriate for your particular purposes and therefore disclaims all liability for any error, loss or other consequence which may arise from you relying on any information in this publication. The Victorian Government, authors and presenters do not accept any liability to any person for the information (or the use of the information) which is provided or referred to in the report. Table of contents
Summary...... v 1 Introduction ...... 1 1.1 Study area...... 2 1.2 Biostratigraphy...... 3 2 Materials and methods...... 4 2.1 Data gather and review...... 4 2.2 Sampling...... 4 2.3 Sample processing and analysis...... 5 2.4 Micropalaeontological zonations...... 5 3 Results...... 6 3.1 Late Cretaceous Sherbrook Group...... 6 3.2 Paleogene Wangerrip Group...... 8 3.3 Palaeogene Nirranda Group...... 9 3.4 Palaeogene–Neogene Heytesbury Group...... 11 4 Conclusions...... 13 References...... 14 Glossary...... 16 Appendix A1 Micropalaeontology study - list of wells and boreholes...... 17 Appendix B1 Otway Basin biozonation chart – Cretaceous...... 20 Appendix B2 Otway Basin biozonation chart – Cenozoic...... 21 Appendix C1 Eastern Onshore Otway Basin stratigraphic chart – Cretaceous...... 22 Appendix C2 Eastern Onshore Otway Basin stratigraphic chart – Cenozoic...... 23 Appendix C3 Central Onshore Otway Basin stratigraphic chart – Cretaceous...... 24 Appendix C4 Central Onshore Otway Basin stratigraphic chart – Cenozoic...... 25 Appendix C5 Western Onshore Otway Basin stratigraphic chart – Cretaceous...... 26 Appendix C6 Western Onshore Otway Basin stratigraphic chart – Cenozoic...... 27 Appendix D1 Early Cretaceous palynozones of the Otway Basin ...... 28 Appendix D2 Late Cretaceous palynozones of the Otway Basin...... 29 Appendix D3 Paleogene palynozones of the Otway Basin...... 30 Attachment A1 Review micropalaeontology summary tables Attachment A2 Integrated biostratigraphy summary tables Attachment A3 Micropalaeontological count data Attachment A4 Foraminifera zonal boundaries Attachment A5 Regional well correlation panels List of figures
Figure 1.1 Otway Basin depocentres with gas accumulations denoted in red...... 2 Figure 1.2 Victorian Gas Program Otway Basin onshore gas study area...... 2 Figure 1.3 A palaeoenvironmentally significant benthic foraminiferal species from 50-100 m palaeodepths in the Otway Basin ...... 3 Figure 1.4 A biostratigraphically important plankic foraminiferal species in the Otway Basin...... 3 Figure 2.1 Onshore Otway Basin location map showing the wells and boreholes with legacy and new micropalaeontological data...... 4
List of tables
Table 2.1 Margalef values for species diversity...... 5 Table 3.1 Wells and boreholes analysed for foraminifera from the Sherbrook Group...... 6 Table 3.3 Boreholes analysed for foraminifera from the Nirranda Group...... 9 Table 3.4 Boreholes analysed for foraminifera from the Heytesbury Group...... 11 Summary
A major review of the biostratigraphy of the onshore Otway Basin was undertaken as part of the Victorian Gas Program (VGP). Biostratigraphy is the study of fossils to date rock formations. The biostratigraphy study was conducted in two parts: (1) a palynology study and (2) a study of micropalaeontology. This report details the findings of the micropalaeontology component of the study.
New micropalaeontology results have been obtained from selected legacy core samples from subsurface rock formations in the Victorian onshore Otway Basin. The results of these analyses fill data gaps in the Geological Survey of Victoria (GSV) historical micropalaeontological dataset. This study was only possible due to the large number of legacy core samples available at the Geological Survey of Victoria Drill Core Library, Werribee and represents one of the most comprehensive, basin-scale biostratigraphic projects to be undertaken in Australia.
As part of the VGP geoscience program, GSV is studying petroleum systems components (reservoir, seal and source), to assess the petroleum prospectivity of the Victorian Otway Basin and estimate the potential for further conventional gas discoveries, onshore and offshore within Victoria’s jurisdiction. The analyses presented in this report contribute to GSV’s regional geological knowledge, allowing more confident assessments of the hydrocarbon prospectivity of the Otway Basin by dating rock formations and understanding the environments the rocks were deposited in.
Over geological time, living organisms such as plants and animals have evolved, diversified and adapted, and some have become extinct. When these organisms die, some of their remains are fossilised. Fossils can be extracted from rocks by palaeontologists. The age of the rock and the environment the organisms lived in can be determined. From this data a robust biostratigraphic framework (where fossils are used to date rock formations) helps to correlate between underground rock layers and understand ancient depositional environments.
GSV engaged MG Palaeo Pty Ltd in Malaga, Western Australia to conduct a review of legacy datasets, compile a list of potential rock samples and undertake new palynological and micropaleontological analysis to infill data gaps. Legacy data from 249 onshore Otway Basin wells and boreholes were reviewed, resulting in the selection of 1060 rock samples for new biostratigraphic analyses from 120 onshore Otway Basin wells and boreholes.
The biostratigraphy study utilised both palynological (fossilised spores, pollen and organic- walled microplankton) and micropalaeontological (fossilised foraminifera) data as these complimentary approaches provide higher resolution correlations when combined. The two techniques often also work better in differing rock types (mud/siltstones versus carbonates), thus allowing a more complete understanding of the stratigraphy. The final program included new analyses of 748 palynology samples (115 wells and boreholes) and 312 micropalaeontological samples (24 wells and boreholes).
For the micropalaeontology study, samples taken from the GSV Drill Core Library were processed at The University of Melbourne. Preparation included chemical disaggregation of a weighed sample using wet sieving. The residue was dried and split using a microsplitter to a known fraction of sample. To achieve quantitative analyses all the microfossils in this fraction were spread out on a picking tray and identified using a binocular microscope and counted. This allowed quantitative estimates of the yield of foraminifera per gram and the percentage and diversity of the assemblages to be calculated from each sample.
The final datasets for the two studies include all the available palynological and micropalaeontological data (both the new data and the fully reviewed legacy data) for the onshore Otway Basin.
The final micropalaeontology datasets are included in the accompanying appendices and attachments in this report. GSV are using the new micropalaeontology analyses presented in this report to refine formation tops in the Otway Basin as part of the VGP prospectivity assessment.
New micropalaeontological results from legacy core | Onshore Otway Basin v 1 Introduction
The Victorian Gas Program (VGP) is a comprehensive program of scientific research and related activities to assess the potential for further discoveries of onshore conventional gas and offshore gas in Victoria, and whether the State’s current underground gas storage capacity could be expanded.
As part of the VGP, the Geological Survey of Victoria (GSV) is assessing the petroleum prospectivity and calculating an estimate of prospective gas resources of the Otway and Gippsland geological basins. The VGP is also looking at the risks, benefits and impacts associated with onshore conventional gas to inform future decisions of Government.
The program includes rock characterisation studies, which involve the identification and selection of rock samples that are representative of source, reservoir and seal rocks from the subsurface onshore Otway Basin. The purpose of these analyses is to use legacy core and cuttings to infill data gaps in the existing GSV database. A better understanding of the geological age of Cretaceous to Cenozoic aged rock units within the Otway Basin will inform petroleum systems modelling, prospectivity studies and resource estimates.
A robust biostratigraphic framework, using fossils to date rock formations, aids correlation between rock units underground. On inspection, some rock units look similar and might be difficult to tell apart. Where the age of the rock has been established, this can increase confidence in identification of the unit. Biostratigraphic analyses also increases understanding of the ancient environments in which sediments were deposited. These assessments contribute to regional geological knowledge, thus allowing more confident assessments of the hydrocarbon prospectivity of the Otway Basin.
GSV engaged Morgan Goodall Palaeo Pty Ltd (MGPalaeo) in Malaga, Western Australia to undertake this biostratigraphic study. MGPalaeo coordinated the project and completed the palynological analysis (Charles et al., 2019) with expert contributions from biostratigraphers from the Australian National University. The micropalaeontological studies detailed in this report were led by The University of Melbourne.
The project began with all available palynological and micropalaeontological data from 249 onshore Otway Basin wells and boreholes being compiled into a single coherent dataset. This data was then captured in a uniform tabulated format that allowed simple upload to databases and geological correlation software packages to use in the next phase of the project. The biozonal information (intervals characterised by different fossils) was also standardised to the latest agreed biostratigraphic schemes for the purpose of consistent correlation and geological interpretations.
Following this data gathering and review phase, a sampling strategy was designed to infill any major stratigraphic data gaps and to address existing correlation issues. This sampling program also aimed to provide a strong geographic and stratigraphic coverage across the entire onshore Otway Basin. The final sampling list was confirmed by the Geological Survey of Victoria prior to instigating this second phase of the project.
For this micropalaeontological study, samples were prepared and analysed at The University of Melbourne. Preparation included chemical disaggregation using hydrogen peroxide of a weighed sample of core using wet sieving with a 63mm sieve. The residue was dried and split using a microsplitter to a known fraction (with typically >100 microfossils). To achieve quantitative analyses all the microfossils in this fraction were spread out on a picking tray and identified using a binocular microscope and counted. This allowed quantitative estimates of the yield of foraminifera per gram and the percentage and diversity of the assemblages to be calculated.
This report summarises the results of quantitative micropalaeontological (foraminiferal) analyses of 312 core samples from the Late Cretaceous to Neogene marine to marginal marine strata from 24 wells and boreholes. The data has been combined with new and pre-existing palynological/micropalaeontological data to aid the stratigraphic review of the onshore subsurface geology.
New micropalaeontological results from legacy core | Onshore Otway Basin 1 1.1 Study area
The Otway Basin is a north-west to south-east trending basin that extends for 500 kilometres along the onshore and offshore parts of south-eastern Australia (Figure 1.1). The onshore Otway Basin geoscience program covers the entire Victorian onshore basin from the northern tip of the Otway Ranges, across south-west Victoria to the South Australian border (Figure 1.2). 141 E 142 E 143 E 144 E
Kanawinka Terrace
Haselgrove Katnook Ladbroke Grove Penola Trough Merino High Tantanoola Trough Tahara Digby Trough Trough Branxholme HAMILTON Mumbannar Platform High Melbourne Gambier Embayment Ardonachie Lake Trough Condah 38 S 38 S High Morenda Trough
Portland Trough Ombersely Sorrento Normanby Terrace Trough Barrabool Graben High Windermere Koroit Trough Tyrendarra Trough Embayment Elingamite Colac COLAC PORTLAND Trough Trough Stoneyford High
Port Campbell Mussel Platform Embayment Ross Creek Halladale Trough Blackwatch Torquay Martha Sub-Basin Fault Netherby Pecten East Otway Pecten Henry Ranges Minerva Casino Snail Terrace Selwyn Voluta Trough Prawn Victoria Shipwreck Platform South Australia Trough
La Bella Late/Early Cretaceous overlap 39 S 39 S Late Cretaceous depocentre Geographe Early Cretaceous depocentre Thylacine Otway Group outcrop Oil / gas accumulation Cenozoic anticline Cenozoic syncline 0 50 Victoria Graben bounding fault Tasmania km Major compressional fault
141 E 142 E 143 E 144 E 145 E
Figure 1.1 Otway Basin depocentres with gas accumulations denoted in red.
Ararat
Penola Daylesford
Casterton Ballarat
Hamilton Bacchus Marsh 38 0 S
Heywood Geelong
Camperdown Portland Port Fairy Colac Warrnambool
Port Lorne Campbell Legend Onshore conventional gas Bass Strait program study area Apollo Bay National Parks Southern Ocean 0 10 20 40 Coastal Waters (3nm limit) km 39 0 S 141 0 E 142 0 E 143 0 E 144 0 E
Figure 1.2 Victorian Gas Program Otway Basin onshore gas study area.
New micropalaeontological results from legacy core | Onshore Otway Basin 2 1.2 Biostratigraphy
Biostratigraphy is the dating of strata using fossils. In this project, microfossils (calcareous) and palynomorphs (organic microfossils) were used to determine the ages of marine and terrestrial strata in the Otway Basin. The palynomorphs distribution is described in Charles et al. (2019). This report focuses on the distribution of marine microfossils. The main marine microfossil in the Otway Basin core samples analysed were Foraminifera.
Foraminifera are an order of single-celled protists that live either on the sea floor or amongst marine plankton. The foraminiferal cell is largely enclosed within a test composed of secreted organic material, secreted minerals (calcite, aragonite or silica) or agglutinated particles from the sea bed. The test consists of a chamber or several chambers usually less than 1 mm across and each interconnected by a foramen or several openings.
Foraminifera may be planktic (floating) or benthic (live in or on the sea bed) and range in size from 50 mm to 1 cm. Benthic foraminifera (Figure 1.3) are very useful in (palaeo) environmental analyses and can be used to distinguish various shallow marine and deep marine environments, however they are not generally used to determine the age of strata in the Otway Basin.
Figure 1.3 A palaeoenvironmentally significant benthic foraminiferal species from 50-100 m palaeodepths in the Otway Basin - Notorotalia howchini (Chapman, Parr & Collins). Note: the scale bar is 100 µm; microfossil from Heywood-10, 369.1 m (adapted from Gallagher & Holdgate, 2000).
Planktic foraminifera are typically used to determine the relative age of strata. This may be achieved by using a combination of their first appearance (when they evolved) and/or their disappearance (when they became extinct). The combined duration of a species existence is its range. Dating using isotopic methods (e.g. Argon/Argon dating) may be used to assign absolute ages to the first and last occurrence of these microfossils. For example, the last appearance of the planktic Globigerinatheka index (Figure 1.4) was 34.61 million years ago, whereas it first appeared 42.64 million years ago according to Gradstein et. al. (2012).
Figure 1.4 A biostratigraphically important planktic foraminiferal species in the Otway Basin Globigerinatheka index (Finlay). Note: the scale bar is 100 µm; microfossil from Narrawaturk-2, 679.4 m (adapted from Gallagher & Holdgate, 2000).
New micropalaeontological results from legacy core | Onshore Otway Basin 3 2 Materials and methods
2.1 Data gather and review
An initial data gathering phase was undertaken at the start of the project. It required the distilling of large volumes of micropalaeontological data from a wide range of academic and industry reports of varying vintages (from the 1960s to 2018). Most of these reports were available through the Geological Survey of Victoria’s online reference collection (available via http://geology.data.vic.gov.au/energy/index.html) or the MGPalaeo digital library. Where possible, the microfossil zonal assignments were updated to the latest zonal schemes, thus allowing for consistent well-to-well correlations. For most reports, the original zonal assignments could be directly correlated with the modern zonation schemes. However, for other zones, the raw count data (when provided) was used for zonal reinterpretations.
2.2 Sampling
Following the compilation and review of pre-existing micropalaeontological data from 101 wells and boreholes (Attachment A1), key stratigraphic intervals of interest (often data deficient sections) were identified for sampling through consultation with the Geological Survey of Victoria. The final sample depths were selected following examination of the available logs and review of suitable lithologies (from both the core and cuttings descriptions). Intervals with available conventional cores were preferentially selected. The sampling was carried out at the Geological Survey of Victoria Drill Core Library in Werribee, Victoria over three sampling visits in November 2018, December 2018 and February 2019. A total of 312 core samples were acquired from 24 wells and boreholes across the Victorian Otway Basin (Appendix A1). The distribution of the wells and boreholes with new analyses is illustrated in Figure 2.1.
Ararat Kyneton Legend Penola Gas Fields National Parks Coastal Waters (3nm limit) Casterton BallaratOtway Basin extent Micropalaeontology Hamilton Samples Mount Ardno-2 Gambier Legacy sample only Legacy and new samples Wanwin-1 Drik Drik-1 Glenaulin-2 Ardonachie-2 38 0 S Heywood Cobboboonee-2 Heywood-10 Geelong Terang-1 Camperdown Portland Koroit-10 WarrnamboolNullawarre-3 Colac Belfast-11 Ecklin-3 Mepunga-12 BePortlfast-4 Fairy Brucknell-2 Mepunga-25 Mepunga-10 Nirranda-6 Cooriejong-2 Timboon-5 Flaümans-1 Lorne Port Waarre-1 Campbell-4 Port Campbell-2 Apollo Bay Southern cean
0 12.5 25 50 Bass Strait km 39 0 S
141 0 E 142 0 E 143 0 E 144 0 E
Figure 2.1 Onshore Otway Basin location map showing the wells and boreholes with legacy and new micropalaeontological data.
New micropalaeontological results from legacy core | Onshore Otway Basin 4 2.3 Sample processing and analysis
The samples were processed for foraminifera (forams) by standard quantitative microfossil techniques to obtain biostratigraphic and palaeoenvironmental data. Each sample was weighed and then processed using hydrogen peroxide followed by heating and wet sieving (>63 µm) to disaggregate the samples. Once dried the sample residues were split (using a micro-splitter) into several fractions to obtain a statistically viable count of >50 (typically over 100) foraminifera and to obtain foraminiferal concentration data (expressed as foraminifera/gm). Some samples (especially the Paleogene and Late Cretaceous samples) yielded less than 50 microfossils, yet these still were useful for biostratigraphy and palaeoenvironmental interpretations.
The preservation state of the assemblages was qualitatively estimated and ranged from excellent, good to poor (where the foraminiferal tests were either broken or fully replaced by diagenetic minerals). Quantitative benthic assemblage and presence/absence biostratigraphic data were compiled from the >63 µm fraction (see well summary tables, Attachment A2). The foraminiferal data are expressed as a percentage of the total fauna including %planktonic forams, %agglutinated forams, % benthic rotaliidae and %miliolids. The total number of species in each sample was counted, this was standardized to the number of foraminiferal specimens counted using the Margalef diversity index:
Diversity = (S–1)/logN
Where: S = number of species, N = number of specimens
Margalef values (Table 2.1) were applied to this study. The same values have been used previously on onshore Otway Basin assemblages (Gallagher & Holdgate, 2000; Gallagher et al., 1999).
Table 2.1 Margalef values for species diversity. Margalef value Diversity <20 Low 30-20 Moderate >30 High
The data was compiled into a series of integrated biostratigraphy excel tables with separate tabs for the micropalaeontology and references (see Attachment A2). The ages and palaeoenvironments interpreted using planktic and benthic foraminiferal data for each well are included in these tables, whilst the raw micropalaeontological count data is included in Attachment A3.
2.4 Micropalaeontological zonations
Benthic (and some planktic) foraminiferal taxonomy followed that of Gallagher et al. (1999) and Li & McGowran (1994) for late Eocene to Miocene strata. The Cenozoic to Cretaceous planktic foraminiferal taxonomy followed Bolli et al. (1985), Pearson et al. (2006), Wade et al. (2018) and McGowran (1965). The Cenozoic foraminiferal biostratigraphy was calibrated to the Gradstein et al., 2012 biochronology tables (Gradstein et al., 2012) (see biozonation charts, Appendix 2). This was used to recalibrate the Taylor Zonation (Taylor, 1971a, b), the Austral realm biozonation (Huber & Quillevere, 2005), and extra range datums listed in Bolli et al. (1985), Pearson et al. (2006), and Wade et al. (2018). Regional Cretaceous (Taylor Zonules) and Paleogene assemblages were identified using the taxonomy and distribution data of Taylor (1964) and McGowran (1965). Limited Late Cretaceous planktic foraminiferal occurrences were recalibrated using Bolli et al. (1985) and Gradstein et al., (2012) supplemented with benthic foraminiferal datums from Bolli et al. (1994) and Taylor (1964).
Palaeoenvironmental interpretation of the foraminiferal assemblages were based on regional modern analogues, where inner shelf = 0–50 m depth, middle shelf = 50–100 m and outer shelf = 100–200 m and comparative Otway regional fossil studies (Boyd & Gallagher, 2001; Gallagher & Holdgate, 2000; Gallagher et al., 1999; and Gallagher et al., 2005).
New micropalaeontological results from legacy core | Onshore Otway Basin 5 3 Results
The following section is a description of the assemblages, age and environments of samples from cored intervals in 24 wells and boreholes from the onshore Otway Basin. It is divided by age and stratigraphic unit. The tabulated results for all samples covering the Sherbrook, Wangerrip, Nirranda and Heytesbury groups are included in Attachment A2.
As a result of this study, a revised biostratigraphic chart for the onshore Otway Basin has been produced for the main Cretaceous and Cenozoic palynological and foraminiferal zonations utilised in the Otway Basin (Appendices B1 and B2). The zonations are tied to the Geologic Time Scale 2012 (Gradstein et al., 2012). The foraminiferal zonations illustrated are: the Tropical Zones (Berggren et al., 1995; Wade et al., 2011), the Planktic Zones (Blow, 1969), the Planktic Taylor Zonation (Taylor, 1971a, b) and the Austral Realm Zones (Huber & Quillevere, 2005). The species that define the zonal boundaries are tabulated in Attachment A4. The palynology zonations depicted are: the Gippsland and Otway basin schemes of Partridge (2006a, b), the Penola Trough Early Cretaceous–Late Jurassic palynostratigraphy of Price (2000; adapted from Price, 1997), along with the preferred zonation used herein [a combination of the Partridge (2006b) and the Morgan et al., 2002b zonations].
Six stratigraphic charts (split into Cenozoic and Cretaceous for the western, central and eastern regions of the onshore Otway Basin) depicting the Geologic Time Scale 2012, the preferred biostratigraphic zonations and the regional lithostratigraphy for the major regional depocentres have also been produced as a result of this study (Appendices C1 to C6).
Regional well correlation panels that include the well logs, the main biostratigraphic tie points and interpreted lithostratigraphy are included as Attachment A5.
3.1 Late Cretaceous Sherbrook Group
Thirty-four samples were analysed for foraminifera from the Sherbrook Group. The samples were from the eight wells and boreholes listed in Table 3.1. While offshore Otway Sherbrook Group assemblages are generally quite diverse and well-preserved (Gallagher et al., 2005), the onshore Sherbrook Group assemblages are typically sparse and of low diversity (Taylor, 1964, 1971a; Boyd & Gallagher, 2001).
Table 3.1 Wells and boreholes analysed for foraminifera from the Sherbrook Group. Well/borehole Sample number Belfast-4 4 Drik Drik-1 2 Flaxmans-1 8 Mepunga-10 1 Nirranda-6 6 Port Campbell-2 10 Port Campbell-4 1 Waarre-1 2
Several Cretaceous units (Duddy, 2003) yielded foraminifera: The Waarre Formation, Flaxman Formation, Belfast Mudstone, Nullawarre Greensand, Skull Creek Mudstone, Paaratte Formation and Timboon Sandstone. The age and assemblages of these units are described below. i Waarre Formation The Waarre Formation in Nirranda-6 yielded poorly to well-preserved, low diversity, sparse (1–33 forams/gm), agglutinated-dominated foraminiferal assemblages (Ammobaculites spp., Marsonella oxycona, Textularia trilobita, Haplophragmoides spp.) with no planktic foraminifera and minor calcareous benthic rotaliids. This assemblage is typical of Late Cretaceous (Taylor, 1965) marginal marine environments in the Otway Basin (Gallagher et al., 2005).
New micropalaeontological results from legacy core | Onshore Otway Basin 6 ii Flaxman Formation The Flaxman Formation in Port Campbell-2 also yielded a sparse (0–14 forams/gm), low diversity, agglutinated foraminiferal fauna with some barren samples. Taxa included Textularia semicomplanata and Ammobaculites spp. with an absence of calcareous benthic rotaliids or planktic foraminifera. A Turonian to Santonian age has previously been ascribed to the Flaxman Formation assemblage in Port Campbell-2 (Taylor, 1964). No additional faunal data was acquired in this study to improve this age estimation. The Flaxman Formation was deposited in a marginal marine environment. iii Belfast Mudstone Foraminiferal diversity (low–moderate) and abundance (12–377 forams/gm) increases markedly in the Belfast Mudstone compared to the underlying Flaxman Formation, reflecting a shift to a shelfal prodelta environment (Gallagher et al., 2005).
In this study the Belfast Mudstone was sampled in Belfast-4, Port Campbell-2 and Flaxmans-1. A diverse, poorly to well-preserved, Late Cretaceous agglutinated foraminifera assemblage including Ammobaculites goodlandensis, Marsonella oxycona, Textularia anceps, Haplophragmoides sp. A, B and C, Dorothia filiformis and D. cornulus) characterises this unit, along with a significant influx of calcareous benthic rotaliids (0–67 %) and occasional planktic foraminifera.
Biostratigraphically important planktics (0–5 %) first occur in this part of the Sherbrook Group. These included Whiteinella archaeicretacea and Hedbergella delrioensis in Belfast-4, which range from the Coniacian to Santonian. The co-occurrences of Heterohelix reussi and Hedbergella delrioensis [denoted as H. trocoidea by Taylor (1964) but reassigned to H. delrioensis herein] at various horizons in Flaxmans-1 and Port Campbell-2 (Taylor, 1964) signify Turonian to Santonian aged strata (Bolli et al., 1985; Gradstein et al., 2012 - see tables in Attachment A2).
Benthic rotaliid foraminifera were common and included Allomorphina pyriformis, Cibicides ribbingi, Hanzawaia californica, Pallaimorphina heliciformis and Praebulimina ovulum. Biostratigraphically useful benthic rotaliid taxa included Gyroidinoides nitida, which typically occurs in the Santonian (Bolli et al., 1994) and Gavellinopsis cenomanica whose last appearance datum defines the top of the A–XA Taylor Zonule in the Santonian (Taylor, 1964). iv Nullawarre Greensand In general, while the assemblages were similar to the Belfast Mudstone, the Nullawarre Greensand foraminiferal yields were lower (0–29 forams/gm) with lower diversity. This reflects the diagenetic alteration of the assemblages in shelfal greensand environments (Boyd & Gallagher, 2001). The Santonian Gyroidinoides nitida was present in the Nullawarre Greensand. v Skull Creek Mudstone The typical Belfast Mudstone foraminiferal assemblages continued into the Santonian Skull Creek Mudstone; however, their diversity and abundance were generally lower (66–120 forams/gm) reflecting shallower shelfal to marginal marine environments. In this unit, the last appearance of Hedbergella delrioensis, Heterohelix reussi and Gyroidinoides nitida in Flaxmans-1 denotes the top of the Santonian. vi Paaratte Formation The overlying Paaratte Formation was dominated by a low diversity, low abundance (15 forams/gm), Late Cretaceous, agglutinated fauna typical of marginal marine environments. A Campanian to Maastrichtian age has previously been ascribed to the Paaratte Formation assemblages in the Port Campbell-2 well (Taylor, 1964). No additional faunal data were acquired in this study to improve this age estimation. vii Timboon Sandstone The one sample analysed from the Timboon Sandstone in Belfast-4 was barren.
New micropalaeontological results from legacy core | Onshore Otway Basin 7 3.2 Palaeogene Wangerrip Group
Fifty-four samples from 16 boreholes (Table 3.2) were analysed for foraminifera in cores from the Wangerrip Group.
Table 3.2 Boreholes analysed for foraminifera from the Wangerrip Group. Well/borehole Sample number Ardno-2 7 Ardonachie-2 4 Belfast-11 3 Cobbobbonee-2 4 Corriejong-2 2 Drik Drik-1 2 Glenaulin-2 4 Heywood-10 4 Mepunga-10 4 Mepunga-12 4 (barren samples) Mepunga-25 3 Nirranda-6 2 Nullawarre-3 2 Timboon-5 5 Wanwin-1 1 Waarre-1 3
All Wangerrip Group units (the Pebble Point Formation, Pember Mudstone and Dilwyn Formation) yielded relatively common foraminifera (McGowran, 1965; Gallagher & Holdgate, 2003). The majority of samples yielded typical Paleogene marginal marine to marine “Cyclammina” agglutinated faunas (Taylor, 1965) including: Haplophragmoides incisa, H. rotundata, H. complanata, Ammodiscus parri, Trochammina spp. and Bathysiphon spp. However, several biostratigraphically useful planktic foraminifera (Bolli et al., 1985; Pearson et al., 2006; Frieling et al., 2018) and common benthic rotaliid species (McGowran, 1965) occurred when palaeoenvironments were shelfal. The age and assemblages of these units are described below. i Pebble Point Formation This unit was either barren of foraminifera or characterised by a low diversity (0–10 forams/gm), marginal marine, “Cyclammina” agglutinated fauna. Occasional rare benthic rotaliid species were present, such as Cibicides whitei, with rare planktic species such as Subbotina patagonica (i.e. Heywood-10). Cibicides whitei is typical of the Paleocene Pebble Point Formation (McGowran, 1965), while S. patagonica ranges from Austral Zones AP4 - Paleocene to AE3 - early Eocene (Huber & Quillevere, 2005; Pearson et al., 2006). ii Pember Mudstone Several cores intersected the Pember Mudstone, yielding poor to well-preserved, low to moderately diverse assemblages. In the majority of cases, most of the calcitic material in the planktic and benthic rotaliid species had been replaced by hematite or jarosite. Nevertheless, the fossilization preserved sufficient detail of various features on the foraminifera to allow confident species identification and biostratigraphic determinations.
Foraminiferal concentrations were variable (from 0–159 forams/gm), although concentrations were generally less than 10 forams/gm. Paleogene benthic rotaliid species (up to 80 % of the total assemblage) characteristic of the Pember Mudstone (McGowran, 1965) were common, including: Alabamina westralensis, Cibicides umbonifer, Cibicidina mariae, Anomalinoides praespissiformis and Bulimina westralensis.
Planktic foraminifera, where present in the marginal marine Pember Mudstone, were usually associated with the Paleogene “Cyclammina” fauna. However, when planktic concentrations are sufficient, two biostratigraphically important taxa are common:Acarinina esnaesnis and Subbotina patagonica, and these were present in the samples examined.
New micropalaeontological results from legacy core | Onshore Otway Basin 8 These taxa constrain the Pember Mudstone to the late Paleocene to early Eocene AP2 to AE4 zones (Huber & Quillevere, 2005). Three of the studied intervals yielded common, biostratigraphically diagnostic planktic assemblages:
1. Ardonachie-2, 569.67 m to 630.02 m: 12–20 % planktics: Chiloguembelina crinata, Acarinina esnaesnis, Subbotina patagonica, Chiloguembelina trinitata, Globanomalina planoconcava = latest Paleocene to earliest Eocene. 2. Glenaulin-2, 666.6 m to 732.13 m: 9–17 % planktics: Chiloguembelina crinata, Acarinina esnaesnis, Subbotina patagonica, Chiloguembelina trinitata, Globanomalina chapmanni = latest Paleocene to earliest Eocene. 3. Wanwin-1, 1216.15 m: 54 % planktics (= outer shelf): Chiloguembelina crinata, Acarinina esnaesnis, Subbotina patagonica, Morozovella aequa = late Paleocene to earliest Eocene. iii Dilwyn Formation Due to the predominantly marginal marine environment of this unit, many samples were either barren or yielded low diversity and abundance, Paleogene, “Cyclammina” agglutinated faunas. A couple of intervals yielded rare planktic foraminifera, such as in Mepunga-25, where the presence of Catapsydrax unicavus and Subbotina eocena suggest an Eocene age. In Nirranda-6 rare Globanomalina australiformis at 605.94 m indicate an early to middle Eocene age.
3.3 Palaeogene Nirranda Group
One hundred samples were analysed for foraminifera in cores from the Nirranda Group. The samples were from 18 boreholes (Table 3.3).
Table 3.3 Boreholes analysed for foraminifera from the Nirranda Group. Well/borehole Sample number Ardno-2 3 Ardonachie-2 3 Belfast-4 3 Belfast-11 2 Brucknell-2 7 Cobbobbonee-2 5 Corriejong-2 5 Ecklin-3 6 Glenaulin-2 2 Heywood-10 10 Koroit-10 4 Mepunga-12 3 (barren samples) Mepunga-25 5 Nirranda-6 6 Nullawarre-3 13 Terang-1 9 Timboon-5 12 Waarre-1 2
All Nirranda Group units (Mepunga Formation, Narrawaturk Marl including the Wangoom Sand Member and Clifton Formation) yielded common foraminifera (Gallagher et al., 1999; Gallagher & Holdgate, 2000; Gallagher & Holdgate, 2003). Gallagher & Holdgate (2000) suggested that the Narrawaturk Marl and the Clifton Formation laterally transitioned to the Lower and Middle Gambier Limestone west of Portland to the Victorian/South Australia border. In this case, the carbonates in the Ardno-2, Ardonachie-2 and Glenaulin-2 most likely intersected the Gambier Limestone. For the purpose of this report, the Narrawaturk Marl and Clifton Formation unit assignment was retained and a dual lithostratigraphic designation is reported in the tabulated biostratigraphy data in Attachment A2.
New micropalaeontological results from legacy core | Onshore Otway Basin 9 i Mepunga Formation The Mepunga Formation is a coarse to very coarse sand unit that overlies the Dilwyn Formation. It was occasionally barren or yielded a sparse calcareous benthic rotaliid fauna (0–8 forams/gm) with minor planktics (0–5 %), especially when deposited in marginal marine or inner to middle shelf environments. In other intervals where foraminiferal concentration increased (13–264 forams/gm), the low diversity assemblage was dominated by Globocassidulina subglobosa and Cibicidoides perforatus benthic rotaliid taxa indicative of middle to outer shelf environments (Gallagher & Holdgate, 2000).
The top of this unit is diachronous. In Timboon-5 the Mepunga Formation has a late Eocene age (Top Globigerinatheka index), whereas in Nullawarre-3 and Koroit-10 the top is earliest Oligocene (Top Subbotina angiporoides). The oldest age for the base of this unit was not determined in this work; however, it is reported to be upper middle Eocene (Gallagher & Holdgate, 2003). ii Narrawaturk Marl (including the Wangoom Sand) Foraminifera were abundant and diverse in the Narrawaturk Marl and sparse to barren in the interbedded Wangoom Sand Member. The top of this unit has an early Oligocene age in most sections (Top Chiloguembelina cubensis, Top Paragloborotalia opima, Top Subbotina angiporoides). The base of the Narrawaturk Marl is as old as the late Eocene (Top Globigerinatheka index). However, it may be late Oligocene in Terang-1 (Top Globoturborotalia euapertura).
The Narrawaturk Marl facies deposited in outer shelf palaeoenvironments yielded 3000– 30000 forams/gm as part of high diversity, well-preserved assemblages with 20–40 % planktics. Common Globocassidulina subglobosa, Cibicidoides perforatus, Gyroidinoides spp. and Trifarina spp. were distinct elements of this outer shelf assemblage (Gallagher et al., 1999; Gallagher & Holdgate, 2000). Inner to middle shelf facies had lower diversities, lower yields and poorer preservation with only minor planktics (0–10 %). Middle to outer shelf facies yielded 10–20 % planktics with common Notorotalia spp. in poor to well-preserved assemblages. The interbedded Oligocene Wangoom Sand Member is interpreted to have been deposited in an inner to middle shelf environment. iii Clifton Formation (Middle Gambier Limestone) The Clifton Formation was analysed in Nirranda-6 and Timboon-5. The unit spans the late Oligocene (Top Globoturborotalia euapertura)/early Oligocene boundary (Top Chiloguembelina cubensis). In the four samples from this interval, preservation was poor to good, planktics were not common (2–14 %) and foraminiferal concentrations ranged from 1155–3900 forams/gm yet were highly diverse. The assemblage was similar to the underlying outer shelf Narrawaturk Marl yet lacked the planktic abundance, therefore this unit is interpreted to have been deposited in a middle to outer shelf environment. Further details about this unit can be found in Gallagher et al. (1999) and Gallagher & Holdgate (2000).
New micropalaeontological results from legacy core | Onshore Otway Basin 10 3.4 Palaeogene–Neogene Heytesbury Group
One hundred and thirty samples were analysed for foraminifera in cores from the Heytesbury Group. The samples were selected from 14 boreholes (Table 3.4).
Table 3.4 Boreholes analysed for foraminifera from the Heytesbury Group. Well/borehole Sample number Ardno-2 4 Ardonachie-2 6 Belfast-11 8 Brucknell-2 9 Cobbobbonee-2 8 Corriejong-2 2 Ecklin-3 2 Glenaulin-2 6 Heywood-10 10 Koroit-10 8 Mepunga-25 23 Nirranda-6 10 Nullawarre-3 14 Terang-1 20
The Gellibrand Marl and Port Campbell Limestone (Upper Gambier Limestone) of the Heytesbury Group yielded common to abundant foraminifera (Gallagher et al., 1999; Gallagher & Holdgate, 2003). Gallagher & Holdgate (2000) suggested that the Gellibrand Marl laterally transitioned to the Upper Gambier Limestone west of Portland to the Victorian/South Australia border. In the absence of the Port Campbell Limestone, this suggests that the carbonates in Ardno-2, Ardonachie-2 and Glenaulin-2 intersected the Upper Gambier Limestone. For the purpose of this report, the Gellibrand Marl assignment was retained and a dual lithostratigraphic designation was used in the tabulated biostratigraphy data (Attachment A2). i Gellibrand Marl (Upper Gambier Limestone) The base of the Gellibrand Marl has a latest Oligocene age (Top Globoturborotalia euapertura) within the AO4 Zone (Huber & Quillevere, 2005), which is equivalent to the P22 zonation of Blow (1969) and the Tropical Zone O7 (Berggren et al., 1995; Wade et al., 2011) and the I2–I1 zones of Taylor (1971 a,b). The top of the Gellibrand Marl appears to be diachronous from the biostratigraphic results presented herein (see also Gallagher & Holdgate, 2000). It is within the latest early Miocene (above Base Praeorbulina bisphaericus datum, base zone F (Taylor, 1971 a,b), the N7 zone of Blow (1969) and the M4 Tropical Zone (Berggren et al., 1995; Wade et al., 2011) and below middle Miocene zones in Ardonachie-2, Belfast-11, Cobbobonee-2, Glenaulin-2, Heywood-10 and Koroit-10. Whereas, the top of this unit is above the Base Praeorbulina glomerosa and Base Orbulina suturalis/O. universa middle Miocene zones in Brucknell-2, Mepunga-25, Nirranda-6, Nullawarre-3 and Terang-1. This apparent diachroneity could accentuated by the lack of cored sections between the early Miocene and middle Miocene and thus should be interpreted with caution.
Foraminiferal concentrations (1000–29000 forams/gm) reached a maximum in most Gellibrand Marl samples (compared to all the underlying units studied) and preservation was generally good to excellent. The percentage of planktics was variable, ranging from 20–65 % (the maximum in the onshore Otway Mesozoic–Cenozoic sequence was recorded in the Terang-1 well) in outer shelf environments, and <20 % in middle to outer shelf samples; no inner shelf benthic taxa (such as Elphidium spp.) were present.
While the taxa Globocassidulina subglobosa and Cibicides perforatus were present in the benthic rotaliid assemblage of the Gellibrand Marl, their abundance was less than the underlying Narrawaturk Marl. Instead the fauna was dominated by fluctuating abundances of smaller delicate forms (~100 µm) such as bolivinids, Uvigerina spp., Epistominella spp., Cassidulina spp., Cassidulinoides spp. and Discorbinella bertheloti. This fauna is typical of outer shelf palaeodepths and nutrient-enriched environments. The shelfal Cibicides spp. were also common. Miliolids (0–11 %) such as Triloculina spp. and Quinqueloculina spp. were present in most samples.
New micropalaeontological results from legacy core | Onshore Otway Basin 11 ii Port Campbell Limestone (Upper Gambier Limestone) The base of the unit (overlying the Gellibrand Marl) is probably diachronous (see also Gallagher & Holdgate, 2000); however, the lack of core acquired limits this interpretation (as discussed above). In the majority of boreholes, the base of this unit was above the Base Orbulina suturalis/O. universa datum and is therefore considered younger than the earliest middle Miocene - M6 Tropical Zone (Berggren et al., 1995; Wade et al., 2011), N8 (Blow, 1969) and E1 (Taylor, 1971 a and b).
The age of the top of the Port Campbell Limestone was difficult to determine. The absence of any late Miocene planktic indices such as Globorotalia pleisiotumida, Globorotalia miotumida (conomiozea), and Neogloboquadryina spp. and the presence of many middle Miocene taxa strongly suggests that the Port Campbell Limestone is no older than the middle Miocene in most sections. In Terang-1 (Top Cassigerinella chipolensis) and Mepunga-25 (Top Globorotalia mayeri sensu stricto) the age of this unit is early late Miocene - M11 Tropical Zone (Berggren et al., 1995; Wade et al., 2011), N14 (Blow, 1969) and C (Taylor, 1971 a and b).
Compared to the Gellibrand Marl assemblages, the Port Campbell Limestone faunas were not as well-preserved with lower foraminiferal concentrations (2000–22000 forams/gm) and lower %planktics (1–20 %). Species designations for the Port Campbell Limestone were more difficult compared to the excellent preservation of the underlying marls. This was due to the increased limestone component and resultant recrystallization of foraminiferal tests. Comparatively lower species diversity and concentrations were common in this unit. This reduction (and reduced %planktics) is related to the shallowing of the Port Campbell Limestone to middle to outer shelf conditions. This unit is characterised by similar (outer shelf), smaller benthic rotaliid taxa to the underlying Gellibrand Marl; however the addition of shallower, inner to middle shelf taxa such as Rosalina spp., Patellina spp., Discorbis spp., Elphidium spp., and Glabratellina sigali with lower %planktics suggests a transition to middle to outer shelf conditions in most sections. In particular, the presence of abundant Notorotalia spp. with these taxa in Cobboboonee-2 suggests the Port Campbell Limestone shallowed to the middle shelf at this location.
New micropalaeontological results from legacy core | Onshore Otway Basin 12 4 Conclusions
Detailed quantitative foraminiferal analyses of 312 core samples from 24 wells and boreholes has revealed the marked variability in marginal marine to outer shelf conditions from the Late Cretaceous to the Neogene. Several key observations can be made:
i. The Late Cretaceous deltaic, shelfal to marginal marine Sherbrook Group yielded occasional planktic foraminifera that may be used to improve regional biochronology. ii. Superb late Paleocene to early Eocene planktic and benthic assemblages were present in the Pember Mudstone of the Paleogene Wangerrip Group. While these microfossils are fully replaced by hematite or jarosite (no calcitic material remains) they indicate that the Pember Mudstone was deposited in a regional flooding event, which could be correlated across the Otway Basin. iii. The Narrawaturk Marl of the Paleogene Nirranda Group is the first major carbonate deposited across the onshore Otway Basin, representing a regional transgression in the Late Eocene. iv. The deepest outer shelf palaeodepths are recorded in the late Oligocene to early Miocene Gellibrand Marl of the Heytesbury Group. The palaeodepth change from the Nirranda to Heytesbury groups may be associated with regional tectonic subsidence. Recommendations for further micropalaeontological studies include:
i. Further sampling of cores from the Belfast Mudstone (Sherbrook Group) for planktic foraminifera to improve regional Late Cretaceous biochronology and correlations. ii. Additional micropalaeontological analyses of all identified late Paleocene to Eocene Pember Mudstone cores (and the location of others) to improve regional correlations and enhance the chronology of southeast Australian palynological zonations.
New micropalaeontological results from legacy core | Onshore Otway Basin 13 References
APPEA, 2019. Australian oil and gas glossary. www.appea.com.au/industry-in-depth/ australian-oil-and-gas-glossary/ Accessed 20th August 2019.
BERGGREN, W.A., KENT, D.V., SWISHER III, C.C. & AUBRY, M.-P., 1995. A revised Cenozoic geochronology and chronostratigraphy. In W.A. Berggren, D.V. Kent, M., -P. Aubry, & J. Hardenbol (eds), Geochronology, Time Scales, and Global Stratigraphic Correlation: A Unified Temporal Framework for a Historical Geology. Society of Economic Paleontologists and Mineralogists, Tulsa, 54, pp. 129–212.
BLOW, W.H., 1969. Late middle Eocene to Recent planktonic foraminiferal biostratigraphy. In P. Bronnimann & H.H. Renz (eds), Proceedings 1st International Conference on Planktonic Microfossils, Geneva, 1967, 1, pp. 199–422.
BOLLI, H.M., BECKMANN, J.-P. & SAUNDERS, J.B., 1994. Benthic foraminiferal biostratigraphy of the south Caribbean region. Cambridge University Press, Cambridge.
BOLLI, H.M., SAUNDERS, J.B. & PERCH-NIELSEN, K., 1985. Plankton stratigraphy. Cambridge University Press, Cambridge.
BOYD, G.A.& GALLAGHER, S.J., 2001. The sedimentology and palaeoenvironments of the Late Cretaceous Sherbrook Group in the Otway Basin. In K.C. Hill & T. Bernecker (eds), Eastern Basin Symposium – A Refocussed Energy Perspective for the Future, Petroleum Exploration Society of Australia, Special Publication, pp. 475–483.
CHARLES, A., HANNAFORD, C., KORASIDIS, V., LIGNUM, J., MACPHAIL, M., MANTLE, D., MORGAN, R., SCHIOLER, P., & YOUNG, M., 2019. New palynology results from legacy core and cuttings, Onshore Otway Basin, Victoria. Victorian Gas Program Technical Report 7. Geological Survey of Victoria. Department of Jobs, Precincts and Regions. Melbourne, Victoria. 62p.
DUDDY, I.R., 2003. Mesozoic a time of change in tectonic regime. In W.D. Birch (ed.), Geology of Victoria. Geological Society of Australia (Victoria Division), Melbourne, pp. 239–286.
FRIELING, J., HUURDEMAN, E.P., REM, C.C.M., DONDERS, T.H., PROSS, J., BOHATY, S.M., HOLDGATE, G.R., GALLAGHER, S.J., MCGOWRAN, B. & BIJL, P.K., 2018. Identification of the Paleocene–Eocene boundary in coastal strata in the Otway Basin, Victoria, Australia. Journal of Micropalaeontology, 37, pp. 317–339.
GALLAGHER, S.J. & HOLDGATE, G., 2000. The palaeogeographic and palaeoenvironmental evolution of a Palaeogene mixed carbonate-siliciclastic cool-water succession in the Otway Basin, Southeast Australia. Palaeogeography, Palaeoclimatology, Palaeoecology, 156, pp. 19–50.
GALLAGHER, S.J. & HOLDGATE, G., 2003. Tertiary a period of transition to marine basin environments. In W.D. Birch (ed.), Geology of Victoria. Geological Society of Australia (Victoria Division), Melbourne, pp. 289–335.
GALLAGHER, S.J., JONASSON, K. & HOLDGATE, G., 1999. Foraminiferal biofacies and palaeoenvironmental evolution of an Oligo–Miocene cool-water carbonate succession in the Otway Basin, Southeast Australia. Journal of Micropalaeontology, 18, pp. 143–168.
GALLAGHER, S.J., TAYLOR, D., APTHORPE, M., STILWELL, J.D., BOREHAM, C.J., HOLDGATE, G.R., WALLACE, M.W. & QUILTY, P.G., 2005. Late Cretaceous dysoxia in a southern high latitude siliciclastic succession, the Otway Basin, southeastern Australia. Palaeogeography Palaeoclimatology Palaeoecology, 223, pp. 317–348.
GEOSCIENCE AUSTRALIA, 2019. Australian Energy Resources Assessment, Appendices -glossary. https://aera.ga.gov.au/#!/glossary Accessed 20th August 2019.
GRADSTEIN, F.M., OGG, G. & SCHMITZ, M., 2012. The Geologic Time Scale 2012 2-Volume Set. Elsevier, United Kingdom. 1176p.
HELBY, R., MORGAN, R. & PARTRIDGE, A.D., 1987. A palynological zonation of the Australian Mesozoic. Memoirs of Association of Australasian Palaeontologists, 4, pp. 1–94.
New micropalaeontological results from legacy core | Onshore Otway Basin 14 HUBER, B.T. & QUILLEVERE, F., 2005. Revised Paleogene planktonic foraminiferal biozonation for the Austral Realm. Journal of Foraminiferal Research, 35, pp. 299–314.
JACKSON, J.A., 1997. Glossary of geology. American Geological Institute, Virginia, US. 769p.
LI, Q. & MCGOWRAN, B., 1994. Miocene upwelling events; neritic foraminiferal evidence from southern Australia. Australian Journal of Earth Sciences, 41, pp. 593–603.
MCGOWRAN, B., 1965. Two Paleogene foraminiferal faunas from the Wangerrip Group, Pebble Point coastal section western Victoria. Proceedings of the Royal Society of Victoria, 79, pp. 9–74.
MORGAN, R., HOOKER, N. & INGRAM, B., 2002b. [MHI 2002 Zonation]. Towards higher palynological resolution in the Australian Mesozoic. Unpublished industry zonation scheme, 10p.
MGP, 2014. Australian palynological zonation. MGPALAEO, Unpublished.
PARTRIDGE, A.D., 2006a. Jurassic–Early Cretaceous Spore-Pollen and Dinocyst Zonations for Australia. In E. Monteil (ed.), Australian Mesozoic and Cenozoic Palynology Zonations – Updated to the 2004 Geologic Time Scale. Geoscience Australia Record, 2006/23.
PARTRIDGE, A.D., 2006b. Late Cretaceous–Cenozoic palynology zonations Gippsland Basin. In E. Monteil (coord.), Australian Mesozoic and Cenozoic Palynology Zonations– updated to the 2004 Geologic Time Scale. Geoscience Australia Record 2006/23.
PEARSON, P.N., OLSSON, R.K., HUBER, B.T., HEMLEBEN, C. & BERGGREN, W.A., 2006. Atlas of Eocene planktonic foraminifera. Cushman Foundation for Foraminiferal Research, Fredericksburg, USA, Special Publication, 41, 513p.
PRICE, P.L., 1997. Permian to Jurassic palynostratigraphic nomenclature of the Bowen and Surat Basins. In P. Green (ed.), The Surat and Bowen Basins, south-east Queensland. Queensland Minerals and Energy Review Series, Queensland Department of Mine and Energy, Brisbane, pp. 137–178.
PRICE, P.L., 2000. Review of the Penola Trough palynostratigraphy. APG unpublished report 651/01. 30p.
SCHLUMBERGER, 2019. Oilfield Glossary. https://www.glossary.oilfield.slb.com/ Accessed 20th August 2019.
SPE INTERNATIONAL, 2019. Petrowiki. petrowiki.org/PetroWiki Accessed 20th August 2019.
TAYLOR, D.J., 1964. Foraminifera and the stratigraphy of the western Victorian Cretaceous sediments. Proceedings of the Royal Society of Victoria, 77, pp. 535–600.
TAYLOR, D.J., 1965. Preservation, composition, and significance of Victorian lower Tertiary ‘Cyclammina faunas’. Proceedings of the Royal Society of Victoria, 78, pp. 143–160.
TAYLOR, D.J., 1971a. Foraminifera and the Cretaceous and Tertiary depositional history in the Otway Basin in Victoria. In H. Wopfner & J.G. Douglas (eds), The Otway Basin of southeastern Australia. Geological Surveys of South Australia and Victoria, Adelaide, pp. 217–233.
TAYLOR, D.J., 1971b. Foraminiferal biostratigraphy of a marginal area of the Otway Basin in Victoria. In H. Wopfner & J.G Douglas (eds.), The Otway Basin of southeast Australia. Geological Surveys of South Australia and Victoria, Adelaide, pp. 235–239.
WADE, B.S., PEARSON, P.N., BERGGREN, W.A. & PÄLIKE, H., 2011. Review and revision of Cenozoic tropical planktonic foraminiferal biostratigraphy and calibration to the geomagnetic polarity and astronomical time scale, Earth-Science Review, 104, pp. pp. 111–142.
WADE, B.S., OLSSON, R.K., PEARSON, P.N., HUBER, B.T. & BERGGREN, W.A., 2018. Atlas of Oligocene planktonic foraminifera. Cushman Foundation for Foraminiferal Research, Fredericksburg, USA, Special Publication, 46, 528p.
New micropalaeontological results from legacy core | Onshore Otway Basin 15 Glossary
Term Explanation Assemblage A group of fossils that occur at the same stratigraphic level. With reference to protists such as foraminifera, the test is composed of foreign particles bound by Agglutinated a mineral cement. Basin A geological depression filled with sediments. Benthic Relating to the substrate that organisms live in or on, such as the sea bed. Biostratigraphy The branch of stratigraphy concerned with fossils and their use in dating rock formations. A hole drilled into the ground to intersect rocks to explore for minerals and Borehole groundwater, or to intersect rocks to understand the rocks types underground. Pieces of rock or formation material that fall into the borehole from the borehole wall after the Cavings hole has been drilled. Fossil material of obvious other origin, either contamination from material introduced in the Contamination drilling fluid, or modern material which has collected after exposure to air. Core Refers to full hole core. The connection of points from location to location where the data suggests that the rocks were Correlation deposited at the same time or have similar and related characteristics Single-celled, flagellate, plankton that form fossilisable organic-walled, resting cysts and are Dinoflagellates predominantly found in marine settings. The phase of operations in which a company searches for oil and gas by carrying out detailed Exploration geological and geophysical surveys followed up where appropriate by exploratory drilling in the most perspective locations. Single-celled organisms (protists) with shells or tests that are commonly fossilised in marine and Foraminifera marginal marine environments. Foraminifera is sometimes shortened to ‘foram’. Any remains, trace or imprint of a plant or animal that has been preserved in the Earth’s crust Fossil from the geological past. Last appearance The last appearance of a species or extinction point in the fossil record. datum Microfossil A generic term to refer to any fossil or fossil fragment that can only be seen with a microscope. The study of the microscopic remains of fossilised animals, plants and protists. For this study, this Micropalaeontology related largely to fossilised foraminifera. Palaeoenvironment An environment in the geological past. The study of organic-walled microfossils, including fossilised spores, pollen, dinoflagellate cysts Palynology and acritarchs. Planktic An ocean dwelling organism that drifts or floats. Side Wall Core Sidewall Core, taken from the side of the borehole, usually by a wireline tool. Reproductive products of plants. Fungi, mosses, liverworts and seedless vascular plants produce Spore-pollen spores and seed-bearing plants produce pollen. The study of rock strata using rock type, fossil evidence and/or absolute age determinations to Stratigraphy correlate between separated strata. A minor subdivision of a zone/biozone. All the subzones used herein are formally defined by Subzone marker taxa. Taxa A term used for a named group of organisms of any rank such as a species, family or class. Test The external secreted shell that is the exoskeleton of an invertebrate such a foraminifera. A hole drilled into the ground to intersect rocks for the purpose of exploring for or producing Well petroleum (hydrocarbons). Minor body of rock in many different categories of stratigraphic classification. In this study all Zone zones are biozones and are defined by their fossil content.
Sources: APPEA (2019); Geoscience Australia (2019); Jackson (1997); Schlumberger (2019); SPE International (2019).
Abbreviations and units g gram/s
GTS Geological Time Scale
µm micrometres
New micropalaeontological results from legacy core | Onshore Otway Basin 16 Appendix A1 Micropalaeontology study - list of wells and boreholes
Number of legacy Number of new Well/Borehole Latitude Longitude Datum Zone micropal. samples micropal. samples Anglesea-1A -38.40496 144.1976683 GDA94 55 2 Ardno-2 -37.780496 140.971741 GDA94 54 14 Ardonachie-2 -38.002062 141.862372 GDA94 54 13 Belfast-11 -38.366181 142.148474 GDA94 54 13 Belfast-4 -38.386899 142.211164 GDA94 54 8 Birregurra-1 -38.329424 143.787071 GDA94 54 19 Branxholme-1 -37.859846 141.792471 GDA94 54 8 Brucknell-2 -38.422871 142.908295 GDA94 54 16 Cobboboonee-2 -38.157483 141.385081 GDA94 54 10 17 Codrington-1 -38.267015 141.940906 GDA94 54 4 Cooriejong-1 -38.440358 143.180121 GDA94 54 5 Cooriejong-2 -38.449979 143.055183 GDA94 54 9 Cressy-1 -38.03376 143.62716 GDA94 54 9 Cundare-1 -38.182411 143.517902 GDA94 54 15 Darlington-1 -37.9596219 143.0563364 GDA94 54 6 Drajurk-8001 (Drajurk 1) -37.65676 141.25348 GDA94 54 2 Drik Drik-1 -37.992098 141.28988 GDA94 54 4 Ecklin-3 -38.354033 142.964473 GDA94 54 8 Eumeralla-1 -38.2096771 141.9331934 GDA94 54 13 Fergusons Hill-1 -38.6200909 143.16023 GDA94 54 4 Flaxmans-1 -38.542176 142.7537586 GDA94 54 49 8 Geelong Oil Flow-1 -38.298851 144.3371148 GDA94 55 3 Glenaulin-2 -38.00575 141.44997 GDA94 54 12 Greenbanks-1 -38.0190816 141.7769107 GDA94 54 3 Heathfield-1 -37.6249593 141.1851312 GDA94 54 5 Heywood-10 -38.13544 141.61697 GDA94 54 30 24 Kanawinka-1 -37.335923 141.098574 GDA94 54 2 Kanawinka-12A -37.32587 141.00362 GDA94 54 4 Kanawinka-13 -37.32586 141.0036 GDA94 54 2 Kanawinka-15 -37.28981 141.04198 GDA94 54 3 Kanawinka-17 -37.30513 141.0307 GDA94 54 2 Kanawinka-18 -37.34299 140.98104 GDA94 54 2 Kanawinka-3 -37.359108 141.071717 GDA94 54 3 Kanawinka-4 -37.37768 141.04709 GDA94 54 5 Kanawinka-5 -37.36732 141.05896 GDA94 54 4 Kanawinka-7 -37.31956 141.00983 GDA94 54 3 Koroit-10 -38.35585 142.31184 GDA94 54 1 12 La Trobe-1 -38.6919718 143.1440661 GDA94 54 7 Mepunga-10 -38.48767 142.67313 GDA94 54 3 5 Mepunga-12 -38.42461 142.69685 GDA94 54 7 Mepunga-25 -38.43718 142.68797 GDA94 54 31 Mepunga-7 -38.3999 142.62817 GDA94 54 13 Mepunga-9 -38.489802 142.673029 GDA94 54 3 Mouzie-1 -38.23425 141.45213 GDA94 54 2 Moyne Falls-1 -38.0669019 142.1926422 GDA94 54 15
New micropalaeontological results from legacy core | Onshore Otway Basin 17 Number of legacy Number of new Well/Borehole Latitude Longitude Datum Zone micropal. samples micropal. samples Nangeela-2 -37.58993 141.21907 GDA94 54 3 Narrawaturk-2 -38.60129 142.87634 GDA94 54 26 Narrawaturk-6 -38.53505 142.86005 GDA94 54 1 Narrawong-13 -38.25825 141.70135 GDA94 54 1 Nepean-37 -38.34281 144.7248 GDA94 55 20 Nirranda-3 -38.46935 142.74857 GDA94 54 8 Nirranda-6 -38.50351 142.8374 GDA94 54 24 North Eumeralla-1 -38.1626924 141.8930222 GDA94 54 70 Nullawarre-3 -38.44267 142.83319 GDA94 54 1 22 Ondit-2 -38.11628 143.63239 GDA94 54 19 Paaratte-1 -38.6164599 143.0008307 GDA94 54 1 Paaratte-2 -38.61881 142.99947 GDA94 54 9 Palpara-4 -37.97482 140.97061 GDA94 54 2 Panmure-2 -38.33981 142.72519 GDA94 54 9 Port Campbell-1 -38.5802323 142.9634832 GDA94 54 38 Port Campbell-2 -38.5985655 142.9884834 GDA94 54 37 10 Port Campbell-4 -38.5393995 142.9745946 GDA94 54 4 1 Portland-3 -38.34408 141.59161 GDA94 54 3 Pretty Hill-1 -38.223342 142.123412 GDA94 54 12 Purrumbete-1 -38.363291 143.2070988 GDA94 54 8 Ross Creek-1 -38.5310157 143.1441215 GDA94 54 8 Rowans-1 -38.4582005 142.7900321 GDA94 54 13 Sherbrook-1 -38.6235657 143.1207073 GDA94 54 11 Tandarook-1 -38.29697 143.06842 GDA94 54 4 Terang-1 -38.25478 142.90157 GDA94 54 2 29 Timboon-1 -38.4884 142.97244 GDA94 54 4 Timboon-5 -38.48529 142.98225 GDA94 54 6 17 Trewalla-5 -38.33027 141.47691 GDA94 54 4 Tullich Structure Hole No-1 -37.52226 141.15412 GDA94 54 2 Tullich Structure Hole No-10 -37.60386 141.35256 GDA94 54 1 Tullich Structure Hole No-11 na na 1 Tullich Structure Hole No-12 na na 1 Tullich Structure Hole No-13 na na 1 Tullich Structure Hole No-14 -37.55802 141.30705 GDA94 54 4 Tullich Structure Hole No-15 -37.6454 141.32441 GDA94 54 1 Tullich Structure Hole No-16 na na 2 Tullich Structure Hole No-17 -37.54023 141.19604 GDA94 54 3 Tullich Structure Hole No-18 -37.63181 141.34815 GDA94 54 1 Tullich Structure Hole No-2 na na 3 Tullich Structure Hole No-3 na na 1 Tullich Structure Hole No-4 -37.53477 141.22433 GDA94 54 3 Tullich Structure Hole No-5 -37.52885 141.25317 GDA94 54 2 Tullich Structure Hole No-6 na na 1 Tullich Structure Hole No-7 na na 2 Tullich Structure Hole No-8 na na 2 Tullich Structure Hole No-9 -37.58147 141.30148 GDA94 54 2 Tullich-1 -37.5224606 141.1501313 GDA94 54 2 Tyrendarra-13 -38.22915 141.83942 GDA94 54 4
New micropalaeontological results from legacy core | Onshore Otway Basin 18 Number of legacy Number of new Well/Borehole Latitude Longitude Datum Zone micropal. samples micropal. samples Waarre-1 -38.54254 143.07623 GDA94 54 2 7 Wangoom-2 -38.37485 142.50482 GDA94 54 11 Wangoom-6 -38.39625 142.46771 GDA94 54 15 Wanwin-1 -37.96743 141.16022 GDA94 54 9 1 Warrain-7 -38.05952 141.1104 GDA94 54 4 Warrion-5 -38.27785 143.5732 GDA94 54 17 Woolsthorpe-1 -38.1332911 142.4959793 GDA94 54 5 Yangery-1 -38.30269 142.37148 GDA94 54 5
New micropalaeontological results from legacy core | Onshore Otway Basin 19 Appendix B1 Otway Basin biozonation chart – Cretaceous
Otway Basin Biozonation Chart: Cretaceous
[USED HEREIN] [USED HEREIN]
Gippsland Otway Basin Otway Basin Spore-Pollen GTS2012 (Gradstein Otway Basin Spore-Pollen Otway Basin Dinocyst Basin Spore-Pollen Zonation Otway Basin Gipplsand Basin et al., 2012) Spore-Pollen SE Australian Zonation Spore-Pollen Zonation (based on Morgan et al., Dinocyst Zonation Dinocyst Zonation Zonation (based on Morgan et al., Zonation (Morgan et al., Zonation 2002b; Helby et al., 1987; (Partridge, 2006a, b) (Partridge, 2006a, b) (Partridge, (Partridge, 2002b; Partridge, 2006a, b) 2002b; (Price, 2000) and MGP, 2014) 2006a, b) 2006a, b) MGP, 2014) Planktonic Foram. Zonation (after Blow, 1969) Otway Sequences (Santos) Otway Sequences (Woodside) Stage Ma Period Zone Subzone Zone Subzone Zone Subzone Zone Subzone
66.5 T5 (T) T10.0 (T) K110MFS 67.0 Upr F. longus T. maastrichtiensis Upper Upper 67.5 C13 Upper K110 68.0 M. druggii M. druggii M. druggii 68.5 C12 69.0 Lower 69.5
70.0 Maastrichtian 70.5 71.0 F. longus 71.5
72.0 F. longus Lower Lower
72.5 Lwr F. longus
73.0 P. reticuloconcavus I. pellucidum 73.5 74.0 74.5 75.0 C11 75.5 76.0 K100 76.5 77.0 I. korojonense I. korojonense 77.5 78.0
78.5 Upper Campanian 79.0 C10 T. lilliei I. korojonense T. lilliei T. lilliei V. spinulosa 79.5 80.0 80.5 Lower K60.0 (KS/C) 81.0 S. haumuriense Upper 81.5 G. rudata Upper G. rudata T. suspectum d C9 X. australis X. australis c 82.0 Lower b N. senectus a 82.5 N. senectus Middle Upper F. sabulosus 83.0 N. senectus F. sabulosus N. semireticulata Lower N. aceras Middle 83.5 N. aceras C. arvensis Acme Lower K90 K58 (KS2) 84.0 Upper I. ponticum Acme b
Late Cretaceous Upper 84.5 I. cretaceum I. rotundatum I. cretaceum a C. porosa Acme Lower b 85.0 C8 T. apoxyexinus T. apoxyexinus a K85 85.5 Middle Upper Santonian O. porifera O. porifera 86.0 C. tripartita Lower 86.5 C. striatoconum Upper 87.0 C. striato- C. vultuosus C. vultuosus Middle 87.5 Trithyrodinium Lower conum
88.0 T. apoxyexinus Lower C7 K80 KS1 88.5 Lower c Coniacian 89.0 89.5 b G. ancorus K. polypes 90.0 G. ancorus Upper aii a 90.5 R. cucullata KT P. mawsonii
91.0 P. mawsonii ai 91.5 C6 P. infusorioides K77 KTC 92.0 L. musa Upper L. musa I. evexus c b P. infusorioides Middle 92.5 Turonian Heterosphaeridium a Acme R. kipperii c 93.0 H. trinalis Lower H. trinalis C5 b 93.5 C. edwardsii Lower C4 P. mawsonii Acme a K75 K50.0 (KC) 94.0 94.5 95.0 95.5 96.0 96.5 97.0 C3 97.5 H. uniforma H. uniforma
98.0 H. uniforma Cenomanian (A. distocarinatus) 98.5 (A. distocarinatus) 99.0 99.5 100.0 100.5 101.0 101.5 102.0 102.5 P. pannosus P. pannosus P. pannosus 103.0 C2 APK6 103.5 104.0 104.5 105.0 105.5 106.0 APK5.2 Upper 106.5 Upper 107.0 Albian 107.5 K63 108.0 APK5 108.5 C. paradoxa C. paradoxa
109.0 C. paradoxa 109.5 APK5.1 Lower
110.0 Lower 110.5 111.0 111.5 C1 K60 112.0 112.5 113.0 113.5 114.0 APK4 C. striatus C. striatus 114.5 C. striatus 115.0 115.5 116.0 116.5 117.0 Upper 117.5 Upper 118.0 APK3.2.2 118.5 119.0 APK3.2 119.5
120.0 APK3.2.1 Aptian 120.5 121.0 121.5 APK3 122.0 C. hughesii 122.5 123.0 P. notensis 123.5 P. notensis Lower APK3.1
Early Cretaceous Lower 124.0
124.5 K55 (KA) K40.0 (KA) 125.0 125.5 126.0 126.5 127.0 127.5 128.0 APK2.2 128.5 129.0
129.5 Barremian 130.0 Upper Upper 130.5 APK2 K40 K30.2 MFS 131.0 (MAM) 131.5 132.0 F. wonthaggiensis APK2.1 132.5 133.0 Hauterivian 133.5 134.0 Lower 134.5 F. wonthaggiensis Lower 135.0
135.5 F. wonthaggiensis 136.0 136.5
137.0 APK1.2.2
137.5 Valanginian
138.0 APK1.2 K25 K20.0 (KV) 138.5 139.0 Upper Upper
139.5 APK1.2.1 K20 140.0 APK1 140.5 R. australiensis 141.0 141.5 142.0
142.5 R. australiensis APK1.1 Lower Lower 143.0 Berriasian R. australiensis 143.5 144.0 144.5
New micropalaeontological results from legacy core | Onshore Otway Basin 20 Appendix B2 Otway Basin biozonation chart – Cenozoic
Otway Basin Biozonation Chart: Cenozoic
[USED [USED HEREIN] HEREIN] [USED HEREIN]
Otway Basin Spore-Pollen Zonation Otway Basin Spore-Pollen GTS2012 (Gradstein (Morgan et al., Zonation Otway Basin Dinocyst et al., 2012) 2002b; MGP, (based on Partridge, 2006b) Zonation (Partridge, 2006b) 2014) Gipplsand Basin Dinocyst Zonation (Partridge, 2006b) Otway Basin Dinocyst Zonation (Partridge, 2006b) Zonation (after Blow, 1969) Gippsland Basin Spore-Pollen Zonation (Partridge, 2006b) Otway Sequenes (Woodside) Planktonic Foraminifera Ma Zone Subzone Zonation (Taylor, 1971a, b) Austral Realm Foraminifera Zonation (Huber & Quillevere, 2005) Planktonic Foraminifera Tropical Zonation (after Berggren et al. 1995; Wade et al., 2011) Otway Basin Spore-Pollen Zonation (Partridge, 2006b) Otway Sequences (Santos) Period Stage Zone Subzone Zone Subzone
* *
0.5 Ionian PT1b P. leonis 1.0 A1 Calabrian PT1a N22 T. pleistocenicus T. pleistocenicus 1.5 Pleistocene T. pleistocenicus 2.0 A. ramulifera Gelasian PL6 A2 2.5 T45.2 MFS (TPL) 3.0 Piacenzian PL5 N21 A3
3.5 * * M. lipsis 4.0 Pliocene PL2 A4 M. lipsis M. lipsis 4.5 Zanclean N19-N20 5.0 PL1 M. choanoph. 5.5 * M14 6.0 N17b Messinian F. bifurcatus F. bifurcatus 6.5 B1 F. bifurcatus 7.0 T40 T40.0 (TM1) M13b 7.5 N17a 8.0 8.5 9.0 M13a N16 Upper 9.5 Tortonian T. bellus Upper
B2 Upper 10.0 M12 N15 10.5 11.0 M11 N14 C 11.5 * * 12.0 T. bellus 12.5 M9b T. bellus Serravallian N12 D1 13.0 Miocene * 13.5 N11 M8 Lower Lower 14.0 M7 N10 D2 T. bellus Lower 14.5 M6 N9 E1 15.0 Langhian 15.5 M5b N8 E2 T35 16.0 * 16.5 M4b 17.0 N7 F M4a Upper 17.5 A. myriosporites P. tuberculatus Upper 18.0 Upper Burdigalian 18.5 M3 G 19.0 N5-N6 Operculodinum Superzone 19.5 20.0 M2 H1 20.5 21.0 21.5 Aquitanian M1b N4b 22.0 H2 22.5 M1a N4a T30 23.0 23.5 Middle O. lacunosus Middle P. tuberculatus 24.0 O7 Middle 24.5 P. tuberculatus 25.0 P22 AO4 P. tuberculatus 25.5 Chattian I1-I2 26.0 O6 26.5 27.0 27.5 O5 AO3 28.0 P21 28.5 O4 29.0 J1 AO2
29.5 Oligocene O3 P20 Lower G. nebulosus Lower T25 (TO) T30.0 (TO) 30.0 P. tuberculatus Lower 30.5 31.0 Rupelian O2 P19 F. leos 31.5 T23 32.0 AO1 32.5 J2 Upper P. stipplatus Upper S. ramosus S. ramosus N. asperus Upper 33.0 O1 P18 P. comatum 33.5 34.0 E16 34.5 S. kakan. T20 T27.1 TR (TE) 35.0 P17/16 AE10 35.5 E15 * Priabonian 36.0 Middle K-L T. magnificus 36.5 N. asperus Middle C. incompositum 37.0 Middle
E14 P15 C. incompositum 37.5 AE8 C. incompositum
38.0 N. asperus 38.5 M N. asperus 39.0 E13 A. luteoides 39.5 Bartonian P14 D. hetero. 40.0 E12 P13 A. biformoides 40.5 AE7 P. crescentis A. biform. 41.0 N E11 41.5 E. partridgei 42.0 P12 Lower Lower N. asperus Lower 42.5 E10 AE6 43.0 O 43.5 E9 P11 AE5 44.0 P10 A. antarct. 44.5 Lutetian T16 TE1 45.0 E8 Eocene 45.5 P. asteris 46.0 46.5 M. perforat. 47.0 E7b AE4 47.5 P9 P P. asperopolus P. asperopolus P. asperopolus 48.0 C. edwardsii 48.5 49.0 E7a 49.5 H. tasmaniense
50.0 H. tasmaniense C. thompson. 50.5 E6 P8 51.0 AE3 S. cainozoicus S. cainozoicus 51.5 E5 P7 W. ornatum Upr M. diversus Upper 52.0 Ypresian Upper M. tenuis 52.5 AE2 M. tenuis R. waipawa. 53.0 53.5 E4 P6b Mid M. diversus P tuberculiformis Middle Middle P. tuberculiformis
54.0 M. diversus T15 54.5 AE1 M. diversus * * P. grandis 55.0 Lwr M. diversus Lower P. grandis Lower A. homomorph. 55.5 E2 S. prominatus * S. prominatus A. hyper. 56.0 P5 M. gigantis M. gigantis 56.5 P5 Upr L. balmei Upper Upper A. reburrus AP4 P. annularis P. annularis Acme 57.0 T20.0 (TP1) 57.5 Thanetian P4c S. dilwyn. 58.0 T10 58.5 P. angulatus P4 P. angulatus E. crassitab. 59.0 P4b AP3 59.5 60.0 Selandian 60.5 * 61.0
P3b AP2 L. balmei 61.5 P3 Lwr L. balmei A. circumtab. Lower
P3a Lower L. balmei
62.0 Paleocene 62.5 P2 P2 63.0 T. verrucosus T. verrucosus P. pyrophor. P1c 63.5 Danian 64.0 P1 AP1 64.5 P1b 65.0 T. evittii Acme 65.5 P1a Pa * T5 (T) T10.0 (T) 66.0 * K110MFS 66.5 Late Cretaceous Maastrichtian C13 Upr F. longus T. maastrich. F. longus Upper F. longus Upper M. druggii M. druggii M. druggii Upper
New micropalaeontological results from legacy core | Onshore Otway Basin 21 Appendix C1 Eastern Onshore Otway Basin stratigraphic chart – Cretaceous
Eastern onshore Otway Basin Stratigraphy: Cretaceous [USED HEREIN] [USED HEREIN]
Otway Basin Spore-Pollen GTS2012 (Gradstein Otway Basin Dinocyst Spore-Pollen Zonation et al., 2012) Zonation (based on Morgan Stoneyford High/ SE Australian (based on Morgan et al., et al., 2002; and Partridge, Zonation 2002b; Helby et al., 1987; Colac Trough/ Gellibrand Trough 2006a, b) Zonation (Price, 2000) and MGP, 2014) Ombersley Trough
(after Blow, 1969) structural structural Planktonic Foram. Stage Ma Period Lithostratigraphy Otway Sequences (Santos) Zone Subzone Zone Subzone N S low high Otway Sequences (Woodside)
C13 Upper Upper M. druggii K110 C12 Lower 70
Maastrichtian Timboon ? Lower Sandstone
F. longus I. pellucidum
75 C11 K100
Campanian C10 T. lilliei I. korojonense 80 K60.0 (KS/C) G. rudata Upper C9 N. senectus X. australis Lower Sherbrook Group Upper F. sabulosus Middle ? N. aceras Lower K90 K58 (KS2) I. cretaceum Upper 85 Santonian C8 T. apoxyexinus Lower K85 Late Cretaceous Upper O. porifera Lower Upper C. vultuosus C. striatoconum Middle K80 KS1 Coniacian C7 Lower
90 G. ancorus Upper KT P. infusorioides C6 K77 KTC Turonian L. musa P. mawsonii Middle C5 H. trinalis Lower C4 K75 K50.0 (KC) 95 ? C3 H. uniforma Cenomanian 100
P. pannosus C2 APK6
105 APK5.2 Upper Upper
Albian Eumeralla K63 APK5 Fm
APK5.1 110 Lower C. paradoxa ? C1 K60
APK4 C. striatus Upper 115 Eumeralla Formation
APK3.2.2 Upper APK3.2 120 Aptian APK3.2.1 APK3 Lower APK3.1 Lower Eumeralla Formation K55 (KA) K40.0 (KA) Early Cretaceous P. notensis 125 Otway Group
APK2.2
130 Barremian APK2 Upper Not penetrated K40K30.2 MFS (MAM)
Hauterivian APK2.1 Pretty Hill Formation
135 Lower F. wonthaggiensis APK1.2.2 K25 K20.0 (KV) Crayfish Subgroup Valanginian APK1.2 APK1.2.1 Upper K20 140 APK1
Not penetrated APK1.1 Lower Berriasian R. australiensis
New micropalaeontological results from legacy core | Onshore Otway Basin 22 Appendix C2 Eastern Onshore Otway Basin stratigraphic chart – Cenozoic
Eastern onshore Otway Basin Stratigraphy: Cenozoic
[USED HEREIN] [USED HEREIN]
GTS2012 (Gradstein Otway Basin Spore-Pollen Stoneyford High/ Zonation et al., 2012) Gellibrand Trough (based on Morgan et al., Colac Trough/ 2002b; Helby et al., 1987; Ombersley Trough and MGP, 2014)
Otway Basin Dinocyst structural structural Otway Sequences (Santos) Gipplsand Basin Dinocyst Zonation (Partridge, 2006b) Zonation (after Blow, 1969) Lithostratigraphy Zonation (Taylor, 1971a, b) Planktonic Foraminifera Austral Realm Foraminifera Zonation (Huber & Quillevere, 2005) Planktonic Foraminifera Tropical Zonation (after Berggren et al. 1995; Wade et al., 2011) Zonation (Partridge, 2006b) Period Sub Period Stage Ma Zone Subzone N S low high * * Ionian * A1 P. leonis Pleistocene Calabrian PT1a N22 T. pleistocenicus Volcanics Volcanics Gelasian * * A. ramulifera Late Pliocene Piacenzian PL5 N21 A3 * * Pliocene Early PL2 A4 M. choanophorum Zanclean N19-N20 M. lipsis 5 Pliocene PL1 * Bluff
* Group
Messinian N17b F. bifurcatus Whalers B1 T40 M13b N17a Late Miocene Tortonian M13a N16 B2 10 M12 N15 Upper M11 N14 C * * Serravallian M9b N12 D1
* T. bellus Middle * * Miocene Miocene * * * Lower M6 N9 E1 15 Langhian M5b N8 E2 T35 * * N7 F M4a Upper Burdigalian M3 G Early Miocene N5-N6 20 M2 H1 Gellibrand Marl Gellibrand Marl Operculodinum Superzone Heytesbury Group Aquitanian M1b N4b H2 * * T30 Middle O7 25 P22 AO4 Chattian I1-I2 O6 P. tuberculatus Clifton Formation CliftonClifton Formation Fm Late Oligocene O5 AO3 P21 Oligocene O4 J1 AO2 T25 (TO) 30 O3 P20 Lower Rupelian O2 P19 Narrawaturk F. leos Narrawaturk Marl T23 AO1 Marl
Early Oligocene J2 O1 P18 Upper S. ramosus P. comatum E16 S. kakanuiensis 35 P17/16 E15 AE10 Group Priabonian * K-L Mepunga Formation Nirranda Middle C. incomp. C. incompositum E14 P15 AE8 M Bartonian E13 P14 D. heterophlycta N. asperus Demons T20 40 * * A. biform. N AE7 Blu E11 E. partridgei Formation P12 Lower E10 AE6 E9 P11 O AE5 * A. antarcticum Lutetian Dilwyn T16 45 Eocene E8 P. asteris Formation E7b AE4 * P9 P P. asperopolus C. edwardsii E7a H. tasman. 50 C. thompsoniae * * AE3 S. cainozoicus W. ornatum Ypresian E5 P7 Upper AE2 M. tenuis R. waipawaense Eastern View E4 P6b Middle P tuberculiformis Formation T15 A. homomorphum AE1 P. grandis Wangerrip Group 55 * * M. diversus Lower E2 S. prominatus Pember * A. hyperacanthum P5 M. gigantis Mudstone P5 Upper A. reburrus Acme AP4 P. annularis Thanetian P4c S. dilwynensis Pebble T10 P4 P. angulatus Point P4b AP3 E. crassitabulata Fm 60 Selandian * Paleocene * A. circumtabulata P3 AP2 P3a * * Lower L. balmei P1c T. verrucosus P. pyrophorum Danian P1 AP1 Not penetrated P1b 65 T. evittii Acme * * Pa T5 (T)
New micropalaeontological results from legacy core | Onshore Otway Basin 23 Appendix C3 Central Onshore Otway Basin stratigraphic chart – Cretaceous
Central onshore Otway Basin Stratigraphy: Cretaceous
[USED HEREIN] [USED HEREIN]
GTS2012 (Gradstein Otway Basin Spore-Pollen Spore-Pollen Otway Basin Dinocyst et al., 2012) Zonation SE Australian Zonation (based on Morgan et al., (based on Morgan et al., Windermere Trough/ Port Campbell Zonation 2002b; Helby et al., 1987; Morenda Tough Elingamite Trough 2002b; and Partridge, 2006a, b) Tyrendarra Embayment Embayment Zonation (Price, 2000) and MGP, 2014) (after Blow, 1969) Planktonic Foram. Stage Ma Otway Sequences (Santos) Otway Sequences (Woodside) Period Zone Subzone Zone Subzone W E N S N S W E Lithostratigraphy K/Pg Bdry C13 Upper Upper K/Pg Boundary Shale K/Pg Boundary Shale Shale M. druggii K110 C12 Timboon Lower Sst 70 Timboon Sandstone Timboon Sandstone
Maastrichtian ? Lower F. longus I. pellucidum
75 C11 K100 Paaratte Formation Paaratte Formation
Campanian C10 T. lilliei I. korojonense 80 K60.0 (KS/C) G. rudata Upper C9 X. australis Lower N. senectus Sherbrook Group Upper F. sabulosus N. aceras Middle Lower SCM Skull Creek Mudstone K90 K58 (KS2) Upper I. cretaceum Nullawarre Greensand Nullawarre Gd K85 85 Santonian C8 T. apoxyexinus Lower Late Cretaceous Upper O. porifera Lower Upper Belfast Mudstone Belfast Mudstone C. vultuosus C. striatoconum Middle K80 KS1 Coniacian C7 Lower Flaxman 90 G. ancorus Upper Flaxman Formation Formation KT P. infusorioides C6 K77 KTC Turonian L. musa P. mawsonii Middle Waarre C5 Waarre Formation H. trinalis Lower Formation C4 K75 K50.0 (KC) 95
C3 H. uniforma Cenomanian 100
P. pannosus C2 APK6
105
APK5.2 Upper Upper Eumeralla Upper Eumeralla Albian APK5 Formation Formation Upper Eumeralla K63 Formation APK5.1 110 Lower C. paradoxa
C1 K60 Upper APK4 Eumeralla C. striatus Heath- 115 eld Formation Sst
APK3.2.2 Upper APK3.2 120 Aptian APK3.2.1 Otway Group APK3 Lower Eumeralla Lower Eumeralla Lower Eumeralla Lower Eumeralla APK3.1 Lower Formation Formation Formation Formation K55 (KA) K40.0 (KA) Early Cretaceous 125 P. notensis
Winder- Winder- APK2.2 mere mere Sst Sst
130 Barremian APK2 Upper K40K30.2 MFS (MAM)
Hauterivian APK2.1
Pretty Hill Formation Pretty Hill Formation Pretty Hill Formation Pretty Hill Formation 135 Lower F. wonthaggiensis APK1.2.2 K25 K20.0 (KV) Valanginian APK1.2 Crayfish Subgroup APK1.2.1 Upper K20 140 APK1
APK1.1 Lower Casterton Formation Not penetrated Casterton Formation Not penetrated Berriasian R. australiensis
New micropalaeontological results from legacy core | Onshore Otway Basin 24 Appendix C4 Central Onshore Otway Basin stratigraphic chart – Cenozoic
Central onshore Otway Basin Stratigraphy: Cenozoic
[USED HEREIN] [USED HEREIN]
Otway Basin Spore-Pollen GTS2012 (Gradstein Zonation et al., 2012) Windermere Trough/ (based on Morgan et al., Elingamite Trough Morenda Region Port Campbell 2002b; Helby et al., 1987; Embayment Tyrendarra Embayment and MGP, 2014) Otway Basin Dinocyst Otway Santos Sequences Gipplsand Basin Gipplsand Basin Dinocyst Zonation (Partridge, 2006b) Zonation (after Blow, 1969) Lithostratigraphy Zonation (Partridge, 2006b) Zonation (Taylor, 1971a, b) Planktonic Foram. Austral Realm Foram. Zonation (Huber & Quillevere, 2005) Planktonic Foram Tropical Zonation (after Berggren et al., 1995; Wade et al., 2011) Period Sub Period Stage Ma Zone Subzone W E N S N S W E
* * Ionian * A1 P. leonis Pleistocene Calabrian PT1a N22 T. pleistocenicus Volcanics Volcanics Volcanics Volcanics Gelasian * * A. ramulifera Late Pliocene Piacenzian PL5 N21 A3 * * Pliocene Early PL2 A4 M. choanophorum Zanclean N19-N20 M. lipsis Hanson Plain Sands 5 Pliocene PL1
* Bluff * Group
Messinian N17b F. bifurcatus Whalers B1 T40 M13b N17a Late Miocene Tortonian M13a N16 B2 10 M12 N15 Upper M11 N14 C * * Port Campbell Port Serravallian M9b N12 D1 Limestone Port Campbell Campbell
* T. bellus Middle * * Limestone Miocene Miocene * * * Lower Limestone M6 N9 E1 Port Campbell Limestone 15 Langhian ? M5b N8 E2 T35 * * Superzone
N7 F m M4a Upper Burdigalian M3 G Early Miocene N5-N6 20 M2 H1 Gellibrand Marl Gellibrand Marl Gellibrand Marl Gellibrand Marl Operculodinu Heytesbury Group Aquitanian M1b N4b H2 * * T30 Middle O7 25 P22 AO4 ? Chattian I1-I2 O6 P. tuberculatus Clifton Formation CliCliftonfton Formation Fm Clifton Formation Clifton Formation Late Oligocene O5 AO3 P21 Oligocene O4 ? J1 AO2 Narrawaturk Marl Narrawaturk Marl T25 (TO) 30 O3 P20 Lower Wangoom Wangoom Rupelian O2 P19 Wangoom Sand Mbr F. leos Sand Mbr Sand Mbr T23 AO1
Early Oligocene J2 O1 P18 Upper S. ramosus P. comatum Narrawaturk Marl Narrawaturk Marl Narrawaturk Marl E16 S. kakanuiensis
35 P17/16 AE10 Group
E15 * m Priabonian Nirranda K-L Middle C. incomp. C. incompositum E14 P15 AE8 Mepunga Formation Mepunga Formation M E13 epunga F Bartonian P14 D. heterophlycta M
N. asperus T20 40 * * A. biform. N AE7 ? ? ? ? ? ? ? E11 E. partridgei P12 Lower E10 AE6 E9 P11 O AE5 * A. antarcticum Lutetian T16 45 Eocene E8 P. asteris E7b AE4 * P9 P P. asperopolus C. edwardsii ormation Dilwyn Formation Dilwyn Formation E7a
H. tasman. yn F 50 C. thompsoniae * * AE3 S. cainozoicus W. ornatum Dil w Ypresian E5 P7 Upper AE2 M. tenuis R. waipawaense E4 P6b Middle P tuberculiformis T15 A. homomorphum AE1 P. grandis Wangerrip Group 55 * * M. diversus Lower E2 S. prominatus * A. hyperacanthum Pember P5 M. gigantis Pember Mudstone Pember Mudstone P5 Upper A. reburrus Acme Mdst AP4 P. annularis Thanetian P4c S. dilwynensis T10 P. angulatus P4b P4 AP3 E. crassitabulata Pebble 60 Pebble Point Formation Pebble Point Formation Selandian * Point Fm Paleocene * A. circumtabulata P3 AP2 P3a * * Lower L. balmei T. verrucosus P. pyrophorum P1c K/Pg Bdry Danian P1 AP1 K/Pg Boundary Shale K/Pg Boundary Shale P1b Shale 65 T. evittii Acme * * Pa T5 (T)
New micropalaeontological results from legacy core | Onshore Otway Basin 25 Appendix C5 Western Onshore Otway Basin stratigraphic chart – Cretaceous
Western onshore Otway Basin Stratigraphy: Cretaceous
[USED HEREIN] [USED HEREIN]
Otway Basin Spore-Pollen Penola Trough/ GTS2012 (Gradstein Otway Basin Dinocyst Spore-Pollen Zonation Mumbannar High/ et al., 2012) Zonation Kanawinka Terrace SE Australian (based on Morgan et al., (based on Morgan et al., far western Portland High Zonation 2002b; Helby et al., 1987; Kanawinka Penola High Portland Trough 2002b; and Partridge, 2006a, b) Trough Trough Zonation (Price, 2000) and MGP, 2014) Terrace Trough Branxholme Ardonachie Lake Condah (after Blow, 1969) Planktonic Foram. Stage Ma Period Lithostratigraphy Otway Sequences (Santos) Zone Subzone Zone Subzone N S N S N S W E Otway Sequences (Woodside) K/Pg Bdy C13 Upper Upper Shale K/Pg Boundary Shale K/Pg Boundary Shale K/Pg Boundary Shale M. druggii K110 C12 Lower Timboon Sandstone 70
Sst Timboon Sandstone Maastrichtian Timboon Timboon Lower
F. longus I. pellucidum
75 C11 K100 Poor biostrat control biostrat Poor
Campanian C10 T. lilliei I. korojonense 80 K60.0 (KS/C) Paaratte Formation Paaratte Paaratte Formation Paaratte G. rudata Upper C9 X. australis Lower
N. senectus Paaratte Sherbrook Group Upper F. sabulosus Middle N. aceras Lower Formation K90 K58 (KS2) I. cretaceum Upper 85 Santonian C8 T. apoxyexinus Lower K85 Late Cretaceous Upper Mount Salt O. porifera Lower Mount Salt Fm equiv./ Upper Belfast Mudstone equiv. Formation equiv. C. vultuosus C. striatoconum Middle K80 KS1 Coniacian C7 Lower
90 G. ancorus Upper Flaxman Formation KT P. infusorioides C6 K77 KTC Turonian L. musa P. mawsonii Middle Waarre Formation C5 H. trinalis Lower C4 K75 K50.0 (KC) 95
C3 H. uniforma Cenomanian 100
P. pannosus C2 APK6
105 APK5.2 Upper Albian K63 APK5 Upper Eumeralla Upper Eumeralla Upper Eumeralla Formation Formation Formation APK5.1 110 Lower C. paradoxa Upper Eumeralla C1 Formation K60
APK4 C. striatus 115 Heath eld Sandstone
APK3.2.2 Upper APK3.2 120 Aptian APK3.2.1 Otway Group APK3 Lower Eumeralla APK3.1 Lower Formation K55 (KA) K40.0 (KA) Early Cretaceous 125 P. notensis Lower Eumeralla Formation Eumeralla Lower APK2.2 Formation Eumeralla Lower Not penetrated 130 Barremian
Upper Not penetrated APK2 Not penetrated K40K30.2 MFS (MAM)
Hauterivian APK2.1
Lower Pretty Hill 135 Formation F. wonthaggiensis APK1.2.2 K25 K20.0 (KV) Valanginian Pretty Hill Formation Pretty Pretty Hill Formation Pretty APK1.2 APK1.2.1 Upper Crayfish Subgroup K20 140 APK1
APK1.1 Lower Casterton Formation Berriasian R. australiensis
New micropalaeontological results from legacy core | Onshore Otway Basin 26 Appendix C6 Western Onshore Otway Basin stratigraphic chart – Cenozoic
Western onshore Otway Basin Stratigraphy: Cenozoic
[USED HEREIN] [USED HEREIN]
Penola Trough/ GTS2012 (Gradstein Kanawinka Terrace et al., 2012) Otway Basin Spore-Pollen Mumbannar High/ Zonation (based on Morgan et al., far western Portland Portland Trough High High 2002b; Helby et al., 1987; Trough Trough
Kanawinka Penola Ardonachie Branxholme and MGP, 2014) Lake Condah Terrace Trough Otway Basin Dinocyst (Santos) Otway Sequences Gipplsand Basin Gipplsand Basin Dinocyst Zonation (Partridge, 2006b) Zonation (after Blow, 1969) Lithostratigraphy Zonation (Taylor, 1971a, b) Planktonic Foraminifera Austral Realm Foraminifera Zonation (Huber & Quillevere, 2005) Planktonic Foraminifera Tropical Zonation (after Berggren et al. 1995; Wade et al., 2011) Zonation (Partridge, 2006b) Period Sub Period Stage Ma Zone Subzone N S N S N S W E * * Ionian * A1 P. leonis Pleistocene Calabrian PT1a N22 T. pleistocenicus Volcanics Gelasian * * A. ramulifera Late Pliocene Piacenzian PL5 N21 A3 * * Pliocene Early PL2 A4 M. choanophorum Zanclean N19-N20 M. lipsis Whalers Blu Formation Whalers Blu Formation 5 Pliocene PL1 * Bluff * Group Messinian N17b F. bifurcatus Whalers B1 T40 M13b N17a Late Miocene Tortonian M13a N16 B2 10 M12 N15 Upper M11 N14 C * * Port Port Serravallian M9b N12 D1 Campbell
* T. bellus Middle * * Campbell Limestone * * * Miocene Miocene Lower Limestone Port Campbell M6 N9 E1 15 Langhian Limestone M5b N8 E2 Gellibrand T35 * * Superzone Marl N7 F m M4a Upper Burdigalian M3 G Early Miocene N5-N6 20 M2 H1 Gellibrand Operculodinu
Marl Gellibrand Marl Heytesbury Group Aquitanian M1b N4b H2 * * Gellibrand T30 Middle Gellibrand Marl O7 Marl 25 P22 AO4 Chattian I1-I2 O6 P. tuberculatus Clifton Clifton Formation Clifton Fm Clifton Formation Late Oligocene O5 AO3 Formation P21 Oligocene O4 NaNarrraawwaturrkk Marl Fm Narrawaturk J1 AO2 Narrawaturk Wangoom O3 P20 Lower Marl T25 (TO) 30 Marl Sand Mbr Rupelian O2 P19 F. leos Narrawaturk Marl T23 AO1
Early Oligocene J2 O1 P18 Upper S. ramosus P. comatum Group
Mepunga Fm Nirranda E16 S. kakanuiensis 35 P17/16 E15 AE10 T20 Priabonian * K-L Middle C. incomp. C. incompositum E14 P15 AE8 M Bartonian E13 P14 D. heterophlycta 40 N. asperus * * A. biform. N AE7 E11 E. partridgei P12 Lower E10 AE6 E9 P11 O AE5 * A. antarcticum Lutetian T16 45 Eocene E8 P. asteris E7b AE4 * P9 P P. asperopolus C. edwardsii E7a H. tasman. 50 C. thompsoniae * * ? ? AE3 S. cainozoicus W. ornatum m Ypresian E5 P7 Upper AE2 M. tenuis Dilwyn Formation Dilwyn Formation Dilwyn Formation R. waipawaense yn F E4 P6b Middle P tuberculiformis T15 A. homomorphum Dil w AE1 P. grandis Wangerrip Group 55 * * M. diversus Lower E2 S. prominatus * A. hyperacanthum Pember P5 M. gigantis Pember Mudstone Pember Mudstone Pember Mudstone P5 Upper A. reburrus Acme AP4 P. annularis Mdst Thanetian P4c S. dilwynensis T10 P4 P. angulatus E. crassitabulata t
P4b AP3 m Pebble Point F oi n Pebble Point Formation Pebble Point Formation
60 ebble P
Selandian * P Formation Paleocene * A. circumtabulata P3 AP2 P3a * * Lower L. balmei T. verrucosus P. pyrophorum P1c K/Pg Boundary Danian P1 AP1 K/Pg Boundary Shale K/Pg Boundary Shale P1b Shale Shale
65 T. evittii Acme K/Pg Bdry * * Pa T5 (T)
New micropalaeontological results from legacy core | Onshore Otway Basin 27 Appendix D1 Early Cretaceous palynozones of the Otway Basin
Early Cretaceous Palynozones of the Otway Basin
Eastern Australian SE Australian Spore-Pollen Spore-Pollen Pan-Australian GTS 2012 Zonation Zonation Dinocyst Zones SANTOS GA Seismic Period Stage (Price 1997) (MGP 2014) Datums (MGP 2014) Subzones Datums Notes Sequences Sequences
C. paradoxa, P. grandis Increase C. torosa (ADP) APK7 Xenascus K70 C. sp. cf. C. brenneri asperatus
Phimopollenites pannosus APK6
P. pannosus Endoceratium P. parvispinosus (ADP) ludbrookiae
APK52 Upper Albian Persistent P. notensis & P. parvispinosus (both PP) P. grandis K63 APK5 Coptospora paradoxa Persistent Canninginopsis D. speciosus (ADP) denticulata
APK51 Lower
C. paradoxa Muderongia tetracantha Aptian dinoflagellate assemblage P. notensis (ADP), persistent LAD is in the early Albian. P. parvispinosus (ADP)
Crybelosporites APK4 striatus K60 Eumeralla
C. striatus Persistent C. hughesii & persistent D. speciosus (PP)
Upper Diconodinium davidii APK322
C. variabilis, F. wonthaggiensis “lunaris”
Aptian APK32 F. dailyii (PP) K55 APK321 M. evansii (ADP) APK3 P. parvispinosus, frequent Pilosisporites spp. Pilosisporites notensis Odontochitina operculata Lower F. wonthaggiensis lunaris APK31 Early Cretaceous
L. belfordii, B. spectabilis
F. asymmetricus
Muderongia australis APK22
Barremian It is very unlikely that any of these zones will be identified in the Otway Basin. *subzones removed for clarity. LAD M. evansii (RM), EC2 Pilosisporites spp., incl. P. notensis Top frequent M. evansii (ADP) K45 C. stylosus (PP) Consistent, modestly diverse Ruffordiaspora spp.
Upper APK2 T. reticulatus (’consistent’ according to ADP) K40 Note that the base T. reticulatus is placed at Muderongia the base of the M. australis Zone herein and APK21 on the HMP2004 charts. However, on the testudinaria Morgan 2002 SA review figure this is placed Hauterivian in the mid S. tabulata Zone. Phoberocysta M. evansii (consistent to frequent) Foraminisporis burgeri wonthaggiensis Note that ADP shows this event in the Upper F. wonthaggiensis Subzone Senoniasphaera tabulata F. wonthaggiensis Lower
Consistent liverwort-like forms; consistent A. spinulosus
Systematophora large Ruffordiaspora spp; areolata
Valanginian APK122 S. “killanoolensis” 5005 Crayfish APK12 D. speciosus M. evansii K20
Egmontodinium Upper torynum APK121 APK1 C. hughesii Batioladinium P. ingramii & A. hispidus reticulatum
Dissimulidinium Ruffordiaspora lobispinosum australiensis EC1.1 Berriasian Cassiculosphaeridia APK11 Lower delicata
Kalyptea wisemaniae K5
Ruffordiaspora spp., incl. R. australiensis Pseudoceratium C. stylosus iehiense
New micropalaeontological results from legacy core | Onshore Otway Basin 28 Appendix D2 Late Cretaceous palynozones of the Otway Basin
Late Cretaceous Palynozones of the Otway Basin
SE Australian Otway Basin Spore-Pollen GTS 2012 Zones Dinocyst Zones Partridge 2006 SANTOS GA Seismic Period Stage (MHI 2002) Subzones Datums (MHI 2002) Subzones Datums Dinocyst Zones Subzones Notes Sequences Sequences M. conorata B. sectilis, Wangerrip T. confessus T1 Upper Upper
G. rudata (frequent) M. conorata K110 Manumiella druggii Manumiella druggii N. senectus (frequent) C. bretonica (frequent)
Maastrichtian Lower
M. druggii I. pellucidum
Forcipites longus
Lower
Isabelidinium pellucidum F. sabulosus
F. longus K100 I. korojonense, I. cretaceum Sherbrook
Isabelidinium korojonense
Upper Isabelidinium Campanian korojonense Tricolporites lilliei
B. sectilis
Lower I. pellucidum, X. australis, X. ceratoides, T. lilliei I. korojonense A. “wisemaniae” K93 Upper A. suggestium N. aceras, X. australis (freq.) *we do not know the markers that ADP used to define his Upper d Otway Basin specific zones and subzones. G. rudata, N. endurus, Xenikoon australis c N. semireticulata Xenikoon australis Lower incr. Nothofagidites spp. b O. porifera (persistent) a X. australis N. tuberculata Nothofagidites Middle senectus Upper N. semireticulata, O. “obesa” F. sabulosus N. tuberculata Nelsoniella aceras Heterosphaeridium (>10%), Nelsonia aceras Middle Lower T. suspectum N. senectus Heterosphaeridium (>20%) Lower LC2 N. aceras K90 Upper Proteacidites (5–10%) A. denticulata, I. belfastense A. cruciformis (1%) b Heterosphaeridium (>20%) Upper Late Cretaceous A. cruciformis (1–4%) Isabelidinium a A. denticulata, I. belfastense I. rotundatum Isabelidinium *I have shifted the I. rotundatum Subzone from the cretaceum cretaceum I. rotundatum top of the I. cretaceum Zone (as shown on ADP 2006), b I. rotundatum so that it aligns with the MGP markers. Lower Santonian a K85 *top Shipwreck Sequence I. cretaceum Middle I. rectangulare *Note that boundary Upper SANTOS have the uncertain Odontochitina top of the Proteacidites spp. (consistent), I. rectangulare Odontochitina porifera porifera Shipwreck Group T. apoxyexinus (rare), T. confessus Lower (not Shipwreck O. sentosa, L. ohaiensis O. porifera C. tripartita Sequence) at K85 boundary, not the A. cruciformis (10%+) C. striatoconum Upper Conosphaeridium K90 boundary. C. striatoconum (consistent) striatoconum *I have moved the P. infusorioides subzones to fit Conosphaeridium Middle better with the MGP markers. Thus I have also striatoconum I. balmei reduced C. striatoconum Zone of ADP 2006 to be Trithyrodinium equivalent to the Upper Subzone of MGP 2018. Tricolporites apoxyexinus Lower C. striatoconum, Coniacian T. marshalli Cupressiacites spike A. sp. cf. griphus, K. polypes, C. nyei K80 c
*Major differences between T. apoxyexinus and P. mawsonii Lower Shipwreck L. cf. ovatus = L. musa (rare) P. cretaceum zones as used by ADP and Morgan. The boundary between these zones is equal to the base of the O. porifera Zone on b the ADP 2006 charts. A. sp. cf. griphus K. polypes Upper H. heterocanthum aii (short acme)
Spinidinium sp. G. ancorus, consistent Palaeohystrichophora Palaeohystrichophora Proteacidites spp. (ADP) infusorioides infusorioides ai LC1.1 *is this extended Heterosphaeridium Acme A. distocarinatus, Aptea spp., A. acuminatum interval realistic? Turonian A. cruciformis (10%+) L. cf. ovatus (consistent) (persistent), common dinos C. distinctum, I. evexus Upper c A. cruciformis (5%+) A. acuminatum (rare) very rare dinos Middle H. trinalis, b P. cretaceum (part range) Heterosphaeridium Phyllocladidites A. distocarinatus (consistent), a K77 MFS C. edwardsii, C. compactum Acme mawsonii Lower L. cf. ovatus (frequent) c Acme C. edwardsii C. edwardsii Lower b Acme C. edwardsii Acme LC1 P. mawsonii, rare C. triplex a K75 H. uniforma, Base frequent dinocysts C. paradoxa in Otway Basin
Hoegisporis uniforma Diconodinium Cenomanian *ADP considers the Cenomanian to be multispinum entirely missing in the Otway Basin. (formerly Morgan noted it may be present as Appendicisporites unidentifiable marginal facies. distocarinatus)
A. cruciformis, common saccates K70
New micropalaeontological results from legacy core | Onshore Otway Basin 29 Appendix D3 Paleogene palynozones of the Otway Basin
Paleocene and Eocene Palynozones of the Otway and Gippsland basins
SE Australian Gippsland Otway Basin Spore-Pollen Basin Partridge 2006 GTS 2012 Zones Subzones Dinocyst Zones SANTOS GA Seismic Epoch Stage (Partridge 2006) (Partridge 2006) Datums Otway Basin Gippsland Basin Datums Sequences Sequences
T. magnificus, C. incompositum
P. pachypolus Stover. kakan. S. kakanuiensis T20 Priabonian Triorites Corrudinium magnificus incompositum Middle extensa S. ornata Gippslandica Corrudinium incompositum
T. magnificus, A. sectus, A. qualumis G. extensa, C. incompositum A. luteoides A. luteoides Bartonian Deflandrea
asperus heterophlycta D. heterophlycta
Achilleodinium Nirranda Nothofagidites biformoides Plicodiporites crescentis
Lower P. crescentis Enneadocysta P. pandus partridgei
No formal subzones N. falcatus E. partridgei Arachnodinium Lutetian T2 antarcticum P. asteris Abundant Nothofagidites spp. Paucilobimorpha M. tenuis H. tasmaniense Eocene asteris T16
M. perforatum M. perforatum
C. edwardsii Proteacidites No formal asperopolus subzones Charlesdowniea edwardsii
C. edwardsii Homotryblium C. thompsoniae Charlesdowniea tasmaniense thompsoniae P. asperopolus C. thompsoniae
Santalumidites cainozoicus S. cainozoicus Wilsonidinium ornatum
Ypresian Upper Myrtaceidites W. ornatum tenuis Rhombodinium M. tenuis waipawaense R. waipawaense, H. tasmaniense diversus
Malvacipollis Proteacidites P. tuberculiformis, P. leightonii, tuberculiformis Middle P. ornatus T15 Apectodinium R. subtile Proteacidites homomorphum grandis Increase P. grandis A. hyperacanthum Lower S. prominatus A. hyperacanthum, S. prominatus, P. pachypolus A. hyperacanthum A. homomorphum M. gigantis M. gigantis Apectodinium Wangerrip Propylipollis P. grandis
Upper reburrus Acme annularis Acme A. reburrus Thanetian P. annularis P. angulatus, S. dilwynensis common L. balmei E. crassitabulata *Index species Proteacidites Eisenackia T10 angulatus present but documentation crassitabulata incomplete V. kopukensis (ADP 2006) A. circumtabulata Selandian T. verrucosus balmei (consistent) Alisocysta Lygistepollenites Lygistepollenites circumtabulata Lower Paleocene P. langstoni P. pyrophorum Tetracolporites verrucosus Palaeoperidinium Danian pyrophorum H. harrisii
Acme T. evittii T5 T. phillipsi, N. flemingii, Trithyrodinium N. emarcidus evittii Acme Acme T. evittii
New micropalaeontological results from legacy core | Onshore Otway Basin 30