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Per Michaelsen - One of the best experts on this subject based on the ideXlab platform.
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mass extinction of peat forming plants and the effect on fluvial styles across the permian triassic boundary northern Bowen Basin australia
Palaeogeography Palaeoclimatology Palaeoecology, 2002Co-Authors: Per MichaelsenAbstract:Abstract The most spectacular extinction event in Earth’s history occurred across the Permian–Triassic boundary. In the northern Bowen Basin, a major coal-bearing sedimentary Basin in eastern Australia, a long-lived (c. 9 Myr), cold climate, peat mire ecosystem collapsed at the Permian–Triassic boundary when the vast majority (c. 95%) of peat-producing plants became extinct. The environmental change marked by the Permian–Triassic boundary is expressed as an abrupt and sharp change in sedimentary regime at the contact between the Rangal Coal Measures and the Sagittarius Sandstone. The stratigraphic record shows no diminution in the thickness, lateral extent or spatial distribution of coal seams prior to the boundary event. The abrupt ecological shift at the Permian–Triassic boundary was coincident with and interrelated to a change in landscape attributes and fluvial style. The boundary shift is considered to reflect a short-period radical atmospheric change accompanied by an abrupt change in plant ecosystems. However, palynological data indicate that it was preceded by a more gradual gross taxonomic progression in the floral succession. The boundary shift is unlikely to reflect change in the tectonic setting of the northern Bowen Basin because the detrital character of clastic sediment supply shows no provenance change within the boundary sequence. The Late Permian fluvial style is characterised by large-scale (up to 1 km wide), sandstone-dominated, low sinuosity, trunk river channel deposits. The trunk river channels were flanked by extensive levee/composite crevasse–splay systems. Channel tracts were relatively stationary in position over enduring periods, and developed stacked sediment accumulations up to 30 m thick. The constrained character of the Late Permian trunk river systems was most likely due to progressive compaction of thick tracts of peat substrate, and the stabilising effect of vegetation adjacent to the channel complex. The well-developed crevasse splays, coupled with the low sinuosity style of the fluvial channels, might suggest a perennial fluvial system, characterised by short discharge periods, as common in high-latitude settings. The fluvial architecture of the Sagittarius Sandstone, the basal formation of the Lower Triassic Rewan Group, is characterised by sheet-like elements, suggestive of broad, shallow channels in a deforested braid-plain setting. The channel deposits are considered to represent highly mobile sandy systems, dominated by a flashy runoff regime. The mass extinction of plants in the northern Bowen Basin at the Permian–Triassic boundary thus had a significant impact on the Early Triassic landscape and fluvial architecture.
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Mass extinction of peat-forming plants and the effect on fluvial styles across the Permian–Triassic boundary, northern Bowen Basin, Australia
Palaeogeography Palaeoclimatology Palaeoecology, 2002Co-Authors: Per MichaelsenAbstract:The most spectacular extinction event in Earth's history occurred across the Permian-Triassic boundary. In the northern Bowen Basin, a major coal-bearing sedimentary Basin in eastern Australia, a long-lived (c. 9 Myr), cold climate, peat mire ecosystem collapsed at the Permian-Triassic boundary when the vast majority (c. 95%) of peat-producing plants became extinct. The environmental change marked by the Permian-Triassic boundary is expressed as an abrupt and sharp change in sedimentary regime at the contact between the Rangal Coal Measures and the Sagittarius Sandstone. The stratigraphic record shows no diminution in the thickness, lateral extent or spatial distribution of coal seams prior to the boundary event. The abrupt ecological shift at the Permian-Triassic boundary was coincident with and interrelated to a change in landscape attributes and fluvial style. The boundary shift is considered to reflect a short-period radical atmospheric change accompanied by an abrupt change in plant ecosystems. However, palynological data indicate that it was preceded by a more gradual gross taxonomic progression in the floral succession. The boundary shift is unlikely to reflect change in the tectonic setting of the northern Bowen Basin because the detrital character of clastic sediment supply shows no provenance change within the boundary sequence. The Late Permian fluvial style is characterised by large-scale (up to 1 km wide), sandstone-dominated, low sinuosity, trunk river channel deposits. The trunk river channels were flanked by extensive levee/composite crevasse-splay systems. Channel tracts were relatively stationary in position over enduring periods, and developed stacked sediment accumulations up to 30 m thick. The constrained character of the Late Permian trunk river systems was most likely due to progressive compaction of thick tracts of peat substrate, and the stabilising effect of vegetation adjacent to the channel complex. The well-developed crevasse splays, coupled with the low sinuosity style of the fluvial channels, might suggest a perennial fluvial system, characterised by short discharge periods, as common in high-latitude settings. The fluvial architecture of the Sagittarius Sandstone, the basal formation of the Lower Triassic Rewan Group, is characterised by sheet-like elements, suggestive of broad, shallow channels in a deforested braid-plain setting. The channel deposits are considered to represent highly mobile sandy systems, dominated by a flashy runoff regime. The mass extinction of plants in the northern Bowen Basin at the Permian-Triassic boundary thus had a significant impact on the Early Triassic landscape and fluvial architecture
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age and significance of the platypus tuff bed a regional reference horizon in the upper permian moranbah coal measures north Bowen Basin
Australian Journal of Earth Sciences, 2001Co-Authors: Per Michaelsen, Peter J. Crosdale, R A Henderson, Christopher FanningAbstract:The Platypus Tuff Bed in the Permian Moranbah Coal Measures provides a Basin-wide marker horizon traceable for over 300 km along strike. The bed is a tephra event unit, the product of a large-scale volcanic eruptive episode involving a pyroclastic volume > 10 km^3. The relatively even thickness (∼1-1.5 m) of the tuff across the entire northern Bowen Basin (∼10 000 km^2) implies a distant source. The tuff is ash-rich and its original geochemistry has been compromised by diagenetic alteration. Crystal content (10-15%) is dominated by quartz, suggesting a rhyolitic association. SHRIMP U-Pb analysis of zircons indicates an age of 258.9 ± 2.7 Ma for the Platypus Tuff Bed, confirming the Late Permian age that has generally been assigned to the Blackwater Group. The age framework now apparent for the coal-bearing Blackwater Group suggests an average depositional rate ranging from ∼133 m/10^6 years for its eastern depocentre in the northern Bowen Basin to ∼70 m/10^6 years in more marginal settings to the west.
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sandstone petrofacies expressions of multiphase Basinal tectonics and arc magmatism permian triassic north Bowen Basin australia
Sedimentary Geology, 2000Co-Authors: Per Michaelsen, R A HendersonAbstract:Abstract Modal analyses of 209 sandstone samples from the Permian–Triassic succession of the northern Bowen Basin, eastern Australia, identify two stratigraphically and compositionally distinct petrofacies. The Lower to Mid Upper Permian Back Creek Group is characterised by Petrofacies A which is quartz-rich (Q82F8L10). It was sourced primarily from cratonic basement terranes to the west, where relief was subdued, and the quartz content of the sandstones may also reflect some reworking in the marine realm with a consequent loss of labile grains. Petrofacies B is volcanolithic and characterises alluvial sediments of the Upper Permian Blackwater and Lower Triassic Rewan Groups. It was sourced from an undissected to transitional magmatic arc provenance located in the contemporary New England Orogen to the east, which supplied abundant pyroclastic debris to the depositional complex. Petrofacies B of the northern Bowen Basin was derived primarily from felsic volcanics, compared to an intermediate association recorded for the southern Basinal sector, indicating significant along-arc variation in volcanic style. As a consequence, its framework grain population is enriched in quartz and is not readily accommodated in the schemes of provenance interpretation currently in use. The consistency of framework detrital modes for sandstones distributed throughout the Blackwater Group (Q24F10L66) allows the recognition of subpetrofacies B1 and shows that the volcanism associated with the magmatic arc system was remarkably uniform in character and activity during deposition of the entire group. The magmatic arc delivered almost identical sedimentary debris over a period of some 9 My in the Late Permian. Relative enrichment of quartz within the Early Triassic Rewan Group (Q49F6L45) relative to the Blackwater Group discriminates subpetrofacies B2 and is attributed to a climatic change and shift in palaeotemperature at the Permian–Triassic boundary. The contact between the marine Back Creek Group (Petrofacies A) and the coal-bearing Blackwater Group (Petrofacies B) represents an abrupt switch in provenance, with little or no evidence of source mixing. The boundary marks the onset of volcanism and associated tectonic uplift in the northern part of the New England Orogen to the east. Sediment from the new source prograded rapidly westwards across the Basin, coincident with regression. Direct evidence of contemporaneous volcanism is widespread in the Blackwater Group as shown by tuffs and tonsteins which are distributed throughout the entire late Permian succession.
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Sedimentary Architecture in Relation to Gas Migration; Late Permian Blackwater Group, Bowen Basin, Australia
1997Co-Authors: Per Michaelsen, Peter J. Crosdale, Robert A. HendersonAbstract:Abstract Coalseam gas in the Bowen Basin is a major resource and potential energy source. Total methane generation from coalseams is around 150 m3/t of coal at bituminous ranks. Methane adsorption isotherms for Bowen Basin coals indicate a maximum sorption capacity of up to 45 m3/t. Excess gas generated of 50 m3/t is not capable of being stored within the coal structure and has migrated upsection. To advance understanding of sedimentary architecture in relation to gas migration we have investigated the lithofacies mosaic of the regionally developed Rangal Coal Measures (RCM), based upon extensive highwall exposures at the Newlands mine. Additional intensive drilling adjacent to the highwalls has allowed reconstruction of the lithofacies patterns and relationships to be mapped in detail over a 50 km2 area. In addition, the regional distribution of the RCM has been mapped by seismic profiling across the entire northern Bowen Basin with stratigraphic control provided by a number of deep stratigraphic drillcores. Facies analysis at Newlands has identified six terrestrial depositional environments: fluvial channels; levee bank to crevasse splay; floodplain; marsh; peat-mire and lacustrine. Temporal control afforded by two tuff beds and three thin coal seams, shows that siliciclastic deposition developed as a succession of rapidly aggrading, overlapping lobe systems. Similar facies mosaics apply to other units of the coal-bearing Blackwater Group. Only the lacustrine facies has the potential of providing stratigraphic seals. Lack of large gas reservoirs in the Bowen Basin is probably due to rapid Basinal aggradation by immature volcanolithic sands and silts and laterally impersistent caprock assemblages, thereby permitting extensive leakage. Gas leakage is estimated at 300-500 trillion cubic feet (Tcf) compared to total gas-in-place of c. 150 Tcf.
J S Esterle - One of the best experts on this subject based on the ideXlab platform.
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the application of natural landform analogy and geology based spoil classification to improve surface stability of elevated spoil landforms in the Bowen Basin australia a review
Land Degradation & Development, 2018Co-Authors: Bevan Emmerton, J S Esterle, Peter D. Erskine, Jon Burgess, Thomas BaumgartlAbstract:Large-scale open cut mining has occurred within the Bowen Basin for over 4 decades, transitioning from shallow mining depths and limited spoil elevation to increased mining depths, prestripping and increasingly elevated mesa-like landforms. As a result of this evolution, the stabilisation of modern constructed landforms is no longer assured through the establishment of vegetation alone. The selection of resilient fragmental spoil types for the construction of final landform surfaces, and as cladding for stabilising steep erosive batters, is a practical methodology that has the potential to significantly improve rehabilitation outcomes, by increasing surface rock cover, roughness, and infiltration and reducing erodibility. An understanding of the properties and behaviour of individual spoil materials disturbed during mining is required. Relevant information from published literature on the geological origins, lithology, and weathering characteristics of individual strata within the Bowen Basin Coal Measures (and younger overlying weathered strata) has been reviewed, related to natural landforms and applied to the surface stability of major strata types when disturbed by mining. A spoil classification derived from geological characteristics and weathering behaviour of identifiable lithologic components has been reviewed and refined, demonstrating the application of use of geological information. This classification system is a tool for the allocation of spoil types and use of categories that have application in premine feasibility investigations, landform design, and material selection and placement. The logic of classifying materials based on their stability in the natural landscape has wider relevance to other mining areas where elevated landforms of sedimentary material are constructed.
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the development of a triassic fold thrust belt in a synclinal depositional system Bowen Basin eastern australia
Tectonics, 2017Co-Authors: A. Babaahmadi, J S Esterle, Renate Sliwa, G RosenbaumAbstract:A synclinal depositional system in eastern Australia (Taroom Trough, Bowen Basin) was affected by folds and thrusts, but the structural style associated with this deformation is not fully understood. Using gridded aeromagnetic data and 2D seismic reflection data, we conducted a structural analysis that unravels the geometry and kinematics of major thrust faults in the eastern-central part of the Taroom Trough. Major structures are the east-dipping Cockatoo, Miles and Taroom faults, and west-dipping Burunga and Glebe faults. Our results show that west-dipping thrusts have a listric geometry that produced gentle hanging-wall anticlines. A north-striking gentle symmetric syncline and anticline pair is also observed to the west of the Burunga Fault. These observations indicate that the deformation in the central Taroom Trough was controlled by decollements in the basement rocks. The decollements and resultant structures were likely developed in response to mild contraction of the synclinal depositional system during the last phase of the Permian-Triassic Hunter-Bowen Orogeny (HBO). The last phase of the HBO also resulted in the reactivation of pre-existing east-dipping Cockatoo and Miles faults. The bulk longitudinal strain, however, in the eastern-central Bowen Basin was low (~2.8% shortening), with the deformation restricted to a relatively narrow zone. In contrast, deformation in the northern Bowen Basin was distributed in a wider fold-thrust belt that accommodated a higher amount of strain. This change in the pattern of deformation along the eastern part of the Bowen Basin could possibly be explained by along-strike variations in the rates of trench advance.
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age of the yarrabee and accessory tuffs implications for the upper permian sediment accumulation rates across the Bowen Basin
Australian Journal of Earth Sciences, 2016Co-Authors: S A Ayaz, J S Esterle, M Martin, Yuri Amelin, Robert S. NicollAbstract:The Yarrabee Tuff is a stratigraphically significant marker across the Bowen Basin separating the Fort Cooper–Burngrove–Fair Hill formations from the overlying Rangal and equivalent coal measures. At least three to four persistent tuffs (referred here as accessary tuffs) beneath the Yarrabee Tuff were recognised in the Fort Cooper Coal Measures as suitable for regional stratigraphic correlations. In this study, we determined the ages of the Yarrabee and accessary tuffs across different morphotectonic zones of the Basin through high-precision U–Pb dating of zircon with the CA-IDTIMS technique. The age of the Yarrabee Tuff is found to be 252.69 ± 0.16 Ma in the Duckworth 11 well, 253.07 ± 0.22 Ma in the Crocker Gully 2 well and <252.58 ± 0.23 Ma in the Peat 1 well. The age range of the Yarrabee Tuff coincides with the previously published date of the Kaloola Tuff Member in Meeleebee 5 suggesting that the tuffs are stratigraphically equivalent. The age range for the accessory tuff 1 is 253.12 ± 0.12 Ma to 252.85 ± 0.16 Ma, 253.45 ± 0.08 Ma for accessory tuff 2 and 253.77 ± 0.17 Ma to 253.57± 0.18 Ma for accessory tuff 3, placing them in the upper Changhsingian Stage. The age of the accessory tuff 6 (less laterally consistent in the Basin) from the Fair Hill Formation is 254.03 ± 0.03 Ma, placing it in the lower Changhsingian Stage. The age-constrained intervals allow the estimation of sedimentation rates using decompacted coal and clastic sediment thickness. In the Taroom Trough, the temporal variation in sedimentation rates is found to be 902 m/Ma in the Fair Hill Formation decreasing to 234.5 m/Ma in the overlying Burngrove Formation, reflecting a decrease in accommodation or sediment supply upwards in the sequence. Across the Basin, the sedimentation rates for the Burngrove Formation are consistently higher in the Taroom Trough ranging between 234.5 and 224.5 m/Ma and lower rates of 112 m/Ma in the Roma Shelf. This regional variation reflects areas of high sedimentation rates that are high accommodation sites recognised by split coal seams and increased interburden. Conversely, low sedimentation rates reflect low accommodation sites, such as the Roma Shelf and the Burunga Anticline that are characterised by coalesced coal seams. The results help to understand stratal relationships across variable accommodation sites, Basin-fill history of the Basin including extent of sediment supply and paleotopographic controls during the evolution of the Bowen Basin. We also discuss criteria for interpreting the results of CA-IDTIMS U–Pb dating and consider the possible geological uncertainties related to either the primary magmatic processes or secondary reworking of tuffs at the site of deposition.
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compositional variation and palaeoenvironment of the volcanolithic fort cooper coal measures Bowen Basin australia
International Journal of Coal Geology, 2016Co-Authors: S A Ayaz, Sandra Rodrigues, S D Golding, J S EsterleAbstract:Abstract An integrated analysis of megascopic lithotype, microscopic maceral and mineral composition, stable carbon isotope and interburden sedimentology from a single well was used to interpret the response of the Late Permian Fort Cooper Coal Measures (FCCM) to regional and global environmental influences. The FCCM are differentiated from underlying, relatively high vitrinite Moranbah Coal Measures, and overlying higher inertinite Rangal Coal Measures in the Bowen Basin by their intercalation with abundant tuff and siliciclastic partings and interbeds. Besides this, there is little described about the variation in the organic composition of the FCCM and its causes. The FCCM can be subdivided into a lower aggradational Fair Hill Formation, transgressed by the shallow marine-derived Black Alley Shale that interfinger with/is overlain by the progradational Middle Main Seams and Burngrove Formation coal measures. The coals are dominantly dull with minor bright bands that are more abundant in the Burngrove Formation representing a change in plant composition. The maceral analysis shows that the coals in the Fair Hill Formation and Middle Main Seams are vitrinite-rich (80–90% mmf) albeit with high mineral matter suggesting the formation of precursory peat under rising water levels and with high sediment (tuff) influx and preservation. The coals in the Burngrove Formation have an increased inertinite content (30% mmf) but are also high in mineral matter suggesting a shift to increased decomposition arising from a fluctuating water table, possibly increased aridity and/or microbial activity. Tuffs occur throughout, and although their frequency is higher in the lower Fair Hill Formation, the preservation of thicker tuffs in the upper Burngrove Formation indicates increased intensity of volcanism that could have modified the environment. Variation in carbon isotope compositions show a parabolic trend, from around − 24.1‰ in the Fair Hill Formation to more variable values in the Middle Main Seams with an overall 13 C-enrichment upwards in the Burngrove Formation, prior to the δ 13 C values becoming negative (depleted between − 1 to − 4% from the average − 24.1‰) in the top seams and into the overlying Rangal Coal Measures. The 13 C-depletion trend in the upper part of the section is unexpected in view of corresponding increase in inertinite content of the coals indicating that the δ 13 C values/plant composition and inertinite content are decoupled, unless the inertinite origin is from intense microbial decay. Similar stable carbon isotope depletion trends have been observed elsewhere in an equivalent stratigraphic interval of the Bowen Basin suggesting that the carbon isotope values are responding to global conditions that cause negative excursions in carbon isotopes before the P-T boundary. Overall, the Basin was continuously subsiding and peats accumulated with constant interruptions from excessive sedimentation and volcanic eruptions. The low proportion of visible thick bright bands coupled with high telovitrinite (mmf) content suggests a marsh to fen environment, with an open canopy and ponding able to preserve volcanic ash falls.
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electrofacies analysis using high resolution wireline geophysical data as a proxy for inertinite rich coal distribution in late permian coal seams Bowen Basin
International Journal of Coal Geology, 2015Co-Authors: A Roslin, J S EsterleAbstract:This paper examines the stratigraphic and geographic distribution of coal composition in main Late Permian coal measures in the Bowen Basin, using coal electrofacies as a proxy for inertinite maceral group content. Data for this research were derived from some 26 wells in the northern part of the Bowen Basin. A companion paper (Roslin and Esterle, 2015, in review) introduced the methodology, which is based on electrofacies analysis and uses high-resolution wireline data (including microresistivity from Compact Micro-Image (CMI) tool and Photoelectric Factor (PEF) data in addition to conventional gamma ray, density and laterolog resistivity) to obtain coal electrofacies. Validation of the methodology was performed by comparison of the weighted average proportion of coal electrofacies to the weighted average proportion of the corresponding coal lithotypes obtained from millimetre scale logging and to the percentage gathered from maceral content analysis. The weighted average proportion of the interpreted dull inertinite-rich coal electrofacies (independent of rank and heat effects) was then analysed to determine their stratigraphic and geographic distribution. From the base upward, the main Late Permian coal bearing units are the Moranbah Coal Measure (MCM), Fort Cooper Coal Measure (FCCM), and Rangal Coal Measure (RCM) and their stratigraphic equivalents across the Basin. The proportion of inertinite-rich dull coal electrofacies increases upwards in the RCM, with some thick and merged seams showing distinctive electrofacies signatures. Within the study area, the coal measures and individual seams split from north to south, reflecting increased subsidence and sediment influx into Basin depocentres. As the seams split, the proportion of inertinite-rich dull coal electrofacies decreases in the tested sample set.
S D Golding - One of the best experts on this subject based on the ideXlab platform.
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biogenic methane production from Bowen Basin coal waste materials
International Journal of Coal Geology, 2017Co-Authors: Hang Zheng, Tianyu Chen, Victor Rudolph, S D GoldingAbstract:Abstract A microbial consortium derived from sewage sludge from the treatment of wastewater (Luggage Point Wastewater Treatment Plant, Brisbane, Australia) has been applied to Jameson Cell (J-cell) rejects (R o,max = 0.96 ± 0.008) of a Bowen Basin coal preparation plant to assess the potential for biogenic methane production. A maximum methane yield of 26.20 μmol/g J-cell rejects (0.64 m 3 CH 4 /ton) was observed, suggesting biogenic methane production from coal waste materials is a feasible process if yields can be improved. Molecular analysis performed on the microbial consortium showed similar microbial community compositions to those observed in natural coal bed environments. The study demonstrates that Australian coal waste materials can be used as a viable feedstock for biogenic methane production using microorganisms that are not native within the coal beds.
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compositional variation and palaeoenvironment of the volcanolithic fort cooper coal measures Bowen Basin australia
International Journal of Coal Geology, 2016Co-Authors: S A Ayaz, Sandra Rodrigues, S D Golding, J S EsterleAbstract:Abstract An integrated analysis of megascopic lithotype, microscopic maceral and mineral composition, stable carbon isotope and interburden sedimentology from a single well was used to interpret the response of the Late Permian Fort Cooper Coal Measures (FCCM) to regional and global environmental influences. The FCCM are differentiated from underlying, relatively high vitrinite Moranbah Coal Measures, and overlying higher inertinite Rangal Coal Measures in the Bowen Basin by their intercalation with abundant tuff and siliciclastic partings and interbeds. Besides this, there is little described about the variation in the organic composition of the FCCM and its causes. The FCCM can be subdivided into a lower aggradational Fair Hill Formation, transgressed by the shallow marine-derived Black Alley Shale that interfinger with/is overlain by the progradational Middle Main Seams and Burngrove Formation coal measures. The coals are dominantly dull with minor bright bands that are more abundant in the Burngrove Formation representing a change in plant composition. The maceral analysis shows that the coals in the Fair Hill Formation and Middle Main Seams are vitrinite-rich (80–90% mmf) albeit with high mineral matter suggesting the formation of precursory peat under rising water levels and with high sediment (tuff) influx and preservation. The coals in the Burngrove Formation have an increased inertinite content (30% mmf) but are also high in mineral matter suggesting a shift to increased decomposition arising from a fluctuating water table, possibly increased aridity and/or microbial activity. Tuffs occur throughout, and although their frequency is higher in the lower Fair Hill Formation, the preservation of thicker tuffs in the upper Burngrove Formation indicates increased intensity of volcanism that could have modified the environment. Variation in carbon isotope compositions show a parabolic trend, from around − 24.1‰ in the Fair Hill Formation to more variable values in the Middle Main Seams with an overall 13 C-enrichment upwards in the Burngrove Formation, prior to the δ 13 C values becoming negative (depleted between − 1 to − 4% from the average − 24.1‰) in the top seams and into the overlying Rangal Coal Measures. The 13 C-depletion trend in the upper part of the section is unexpected in view of corresponding increase in inertinite content of the coals indicating that the δ 13 C values/plant composition and inertinite content are decoupled, unless the inertinite origin is from intense microbial decay. Similar stable carbon isotope depletion trends have been observed elsewhere in an equivalent stratigraphic interval of the Bowen Basin suggesting that the carbon isotope values are responding to global conditions that cause negative excursions in carbon isotopes before the P-T boundary. Overall, the Basin was continuously subsiding and peats accumulated with constant interruptions from excessive sedimentation and volcanic eruptions. The low proportion of visible thick bright bands coupled with high telovitrinite (mmf) content suggests a marsh to fen environment, with an open canopy and ponding able to preserve volcanic ash falls.
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carbon dioxide rich coals of the oaky creek area central Bowen Basin a natural analogue for carbon sequestration in coal systems
Australian Journal of Earth Sciences, 2013Co-Authors: S D Golding, I T Uysal, K A Baublys, Chris Boreham, Robert Bolhar, G K W Dawson, J S EsterleAbstract:High-CO2-containing coal seams in the Oaky Creek area of the Bowen Basin, eastern Australia provide natural analogues of the processes likely to occur as a result of CO2 injection and storage in coal systems. We conducted mineralogical, stable and radiogenic isotope and major element analyses of mudstones and sandstones adjacent to the coal seams and stable isotope and compositional studies of coal seam gas desorbed from the coals to establish the impact of the high CO2 levels and the mechanisms that keep the CO2 naturally sequestered. Siderite is the earliest carbonate phase present and occurs with kaolinite in mudstones and sandstones. It is interpreted to have formed under low-temperature, reducing conditions where methanogenesis has produced residual 13C-enriched CO2. Enhanced kaolinite concentrations adjacent to a low-CO2-containing coal seam reflect interaction with acidic fluids produced during the coalification of organic matter. Stable isotope data for carbonates and Rb–Sr isochron ages for illit...
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rare earth element fractionation in authigenic illite smectite from late permian clastic rocks Bowen Basin australia implications for physico chemical environments of fluids during illitization
Chemical Geology, 2003Co-Authors: Tonguc I Uysal, S D GoldingAbstract:REE analyses were performed on authigenic illitic clay. minerals from Late Permian mudrocks, sandstones and bentonites from the Bowen Basin (Australia). The mixed-layer illite-smectite exhibit REE patterns with an obvious fractionation of the HREE from the LREE and MREE, which is an apparent function of degree of illitization reaction. The highly illitic (R greater than or equal to 3) illite-smectite from the northern Bowen Basin show a depletion of LREE relative to the less illitic (R=0 and 1) clays. In contrast, an enrichment of HREE for the illite-rich clays relative to less. illitic clays is evident for the southern Bowen Basin samples. The North American Shale Composite-normalized (La/Lu)(sn) ratios show negative correlations with the illite content in illite-smectite and positive correlations with the delta(18)O values of the clays for both the northern and southern Bowen Basin samples. These correlations indicate that the increasing depletion of LREE in hydrothermal fluids is a function of increasing water/rock ratios in the northern Bowen Basin. Good negative correlations between (La/Lu)(sn) ratios and illite content in illite-smectite from the southern Bowen Basin suggest the involvement of fluids with higher alkalinity and higher pH in low water/ rock ratio conditions. Increasing HREE enrichment with delta(18)O decrease indicates the effect of increasing temperature at low water/rock ratios in the southern Bowen Basin. Results of the present study confirm the conclusions of some earlier studies suggesting that REE in illitic clay minerals are mobile and fractionated during illitization and that this fact should be considered in studies of sedimentary processes and in identifying provenance. Moreover, our results show that REE systematic of illitic clay minerals can be applied as an useful technique to gain information about physico-chemical conditions during thermal and fluid flow events in certain sedimentary Basins. (C) 2003 Elsevier Science B.V. All rights reserved.
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petrographic and isotope constraints on the origin of authigenic carbonate minerals and the associated fluid evolution in late permian coal measures Bowen Basin queensland australia
Sedimentary Geology, 2000Co-Authors: I T Uysal, S D Golding, M GliksonAbstract:Authigenic carbonate minerals are ubiquitous throughout the Late Permian coal measures of the Bowen Basin, Queensland, Australia. In the northern Bowen Basin, carbonates include the following assemblages: siderite I (delta O-18(SMOW) = +11.4 to + 17%, delta C-13(PDB) = - 5.3 to + 120), Fe-Mg calcite-ankerite-siderite II mineral association (delta O-18(SMOW) = +7.2 to + 10.20, delta C-13(PDB) = 10.9 to - 1.80 for ankerite) and a later calcite (delta O-18(SMOW) = +5.9 to + 14.60, delta C-13(PDB) = -11.4 to + 4.40). In the southern Bowen Basin, the carbonate phase consists only of calcite (delta O-18(SMOW) = +12.5 to + 14.80, delta C-13(PDB) = -19.4 to + 0.80), where it occurs extensively throughout all stratigraphic levels. Siderite I occurs in mudrocks and sandstones and predates all other carbonate minerals. This carbonate phase is interpreted to have formed as an early diagenetic mineral from meteoric waters under cold climate and reducing conditions. Fe-Mg calcite-ankerite-siderite Il occur in sandstones as replacement of volcanic rock fragments. Clay minerals (illite-smectite, chlorite and kaolinite) postdate Ca-Fe-Mg carbonates, and precipitation of the later calcite is associated with clay mineral formation. The Ca-Fe-Mg carbonates and later calcite of the northern Bowen Basin are regarded as having formed as a result of hydrothermal activity during the latest Triassic extensional tectonic event which affected this part of the Basin, rather than deep burial diagenesis during the Middle to Late Triassic as previously reported. This hypothesis is based on the timing relationships of the authigenic mineral phases and the low delta O-18 values of ankerite and calcite, together with radiometric dating of illitic clays and recently published regional geological evidence. Following the precipitation of the Ca-Fe-Mg carbonates from strongly O-18-depleted meteoric-hydrothermal fluids, continuing fluid circulation and water-rock interaction resulted in dissolution of these carbonate phases as well as labile fragments of volcaniclastic rocks. Subsequently, the later calcite and day minerals precipitated from relatively evolved (O-18-enriched) fluids. The nearly uniform delta O-18 values of the southern Bowen Basin calcite have been attributed to very low water/rock ratio in the system, where the fluid isotropic composition was buffered by the delta O-18 values of rocks. (C) 2000 Elsevier Science B.V. All rights reserved.
Julian C Baker - One of the best experts on this subject based on the ideXlab platform.
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Sandstone Diagenesis: Recent and Ancient - Early diagenetic siderite as an indicator of depositional environment in the Triassic Rewan Group, southern Bowen Basin, eastern Australia
Sedimentology, 1996Co-Authors: Julian C Baker, Jochen Kassan, P. Joe HamiltonAbstract:Early concretionary and non-concretionary siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these siderites in order to provide information on the depositional environment of the host rocks. The siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the siderites indicates that only meteoric porewaters were involved in siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted siderite can be produced at shallow burial depths in anoxic non-marine sediments.
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early diagenetic siderite as an indicator of depositional environment in the triassic rewan group southern Bowen Basin eastern australia
Sedimentology, 1996Co-Authors: Julian C Baker, Jochen Kassan, Joe P HamiltonAbstract:Early concretionary and non-concretionary siderites are common in subsurface Triassic sandstones and mudrocks of the Rewan Group, southern Bowen Basin. A detailed petrological and stable isotopic study was carried out on these siderites in order to provide information on the depositional environment of the host rocks. The siderites are extremely pure, containing 85–97 mol% FeCO3, and are commonly enriched in manganese. δ13C (PDB) values are highly variable, ranging from - 18·4 to +2·9‰, whereas δ18O (PDB) values are very consistent, ranging from - 14·0 to - 10·2‰ (mean= - 11·9 ± 1·0‰). The elemental and oxygen isotopic composition of the siderites indicates that only meteoric porewaters were involved in siderite formation, implying that host rocks accumulated in totally non-marine environments. The carbon isotopic composition of the siderites is interpreted to reflect mixing of bicarbonate/carbon dioxide generated by methane oxidation and methanogenesis. Very low δ13C values demonstrate that, contrary to current views, highly 13C-depleted siderite can be produced at shallow burial depths in anoxic non-marine sediments.
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permian evolution of sandstone composition in a complex back arc extensional to foreland Basin the Bowen Basin eastern australia
Journal of Sedimentary Research, 1993Co-Authors: Julian C Baker, Christopher R Fielding, Patrice De Caritat, Melville M WilkinsonAbstract:ABSTRACT The Bowen Basin is a Permo-Triassic, back-arc extensional to foreland Basin that developed landward of an intermittently active continental volcanic arc associated with the eastern Australian convergent plate margin. The Basin has a complex, polyphase tectonic history that began with limited back-arc crustal extension daring the Early Permian. This created a series of north-trending grabens and half grabens which, in the west, accommodated quartz-rich sediment derived locally from surrounding uplifted continental basement. In the east, coeval calc-alkaline, volcanolithic-rich, and volcaniclastic sediment was derived from the active volcanic arc. This early extensional episode was followed by a phase of passive thermal subsidence accompanied by episodic compression during the late Early Permian to early Late Permian, with little contemporaneous volcanism. In the west, quartzose sediment was shed from stable, polymictic, continental basement immediately to the west and south of the Basin, whereas volcanolithic-rich sediment that entered the eastern side of the Basin during this time was presumably derived from the inactive, and possibly partly submerged, volcanic arc. During the late Late Permian, flexural loading and increased compression occurred along the eastern margin of the Bowen Basin, and renewed volcanism took place in the arc system to the east. Reactivation of this arc led to westward and southward spread of volcanolithic-rich sediment over the entire Basin. Accordingly, areas in the west that were earlier receiving quartzose, craton-derived sediment from the west and south were overwhelmed by volcanolithic-rich, arc-derived sediment from the east and north. This transition from quartz-rich, craton-derived sediments to volcanolithic-rich, arc-derived sediments is consistent with the interpreted back-arc extensional to foreland Basin origin for the Bowen Basin.
Christopher R Fielding - One of the best experts on this subject based on the ideXlab platform.
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new palaeogeographic synthesis of the Bowen Basin of central queensland
Bowen Basin Symposium 2000. The New Millennium - Geology, 2000Co-Authors: Christopher R Fielding, R Sliwa, R J Holcombe, J KassanAbstract:INTRODUCTION At the previous two Bowen Basin Symposia, we have presented compilations of palaeogeographic maps (Fielding et al., 1990a, 1995). These articles, and the maps therein, summarised the Permian-Triassic evolution of the Bowen Basin, based on the understanding of the time. Significant progress has been made in this area in the past five years, and in this paper we present a time-space relationship diagram (Fig. 1) together with an expanded series of newly modified palaeogeographic maps (Fig. 2) for the Bowen Basin and terrains to the east and west. In addition to further defining the original extent of the Bowen Basin, this analysis provides new insights into the relationships between Permian-Triassic tectonic events and Basin stratigraphy. In addition to the literature cited in our previous Bowen Basin Symposia papers, the results on which the new maps are based (including extensive compilations of palaeocurrent data) have been published in a series of articles over the past five years, notably Fielding et al. (1996, 1997a, b), Pattison et al. (1996), Faraj et al. (1996), Kassan & Fielding (1996a, b), Holcombe et al. (1997a, b) and Allen et al. (1998). As per our discussion in Fielding et al. (1995), we shall restrict the term Bowen Basin to the named structural feature, and use the term "Basin" in reference to the original depositional entity, which we believe is considerably more extensive. The reader is referred to discussions of Basin definition and stratigraphic relationships in Fielding et al. (1995, 1997a) for further information.
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submarine mass wasting deposits as an indicator of the onset of foreland thrust loading late permian Bowen Basin queensland australia
Terra Nova, 1997Co-Authors: Christopher R Fielding, Christopher J Stephens, R J HolcombeAbstract:In the eastern part of the Permo-Triassic Bowen Basin of Queensland, Australia, a transition from passive, thermal subsidence to flexural (foreland Basin) subsidence is recorded within the Upper Permian stratigraphy. Two coarse-grained intervals containing deposits of mass-wasting processes occur within an otherwise siltstone-dominated succession over 1500 m thick (the Moah Creek Beds and equivalents). These intervals can be traced over at least 350 km north-south, along the structural eastern margin of the Basin. The lower of the coarse-grained intervals is spectacularly exposed in the banks of the Fitzroy River, west of Rockhampton. Here, interbedded sandstones and siltstones of marine shelf origin are abruptly truncated by a mudrock succession containing evidence of slumping and contemporaneous magmatic activity. This unit passes up-section into packages of mass-flow conglomerates and diamictites, interpreted to have formed on an unstable submarine slope. The character of the mass-flow deposits, their stratigraphic position and lateral extent are interpreted in terms of destabilization of a sloping marine surface by pulsed, subsurface thrust propagation.
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cleat mineralization of upper permian baralaba rangal coal measures Bowen Basin australia
Geological Society London Special Publications, 1996Co-Authors: Basim S M Faraj, Christopher R Fielding, Ian D R MackinnonAbstract:Coals from the Permo-Triassic Bowen Basin have been investigated using a variety of complementary analytical techniques. Face cleat minerals in the studied samples are dominated by authigenic clays, notably pure illite or illite-chlorite mixtures. Butt cleats and joints are dominated by carbonates, mostly calcite with less abundant ferroan calcite, ankerite and siderite. K/Ar ages of cleat-fill illites and one fracture illite-smectite fill indicate three phases of illite formation during the Triassic: (1) an early phase with ages clustered around 244 Ma ago; (2) a second phase about 232 Ma ago; and (3) the latest phase about 219 Ma ago. Thermal modelling of selected boreholes from the study area and other geological data indicate that the first phase of illitization occurred when the coal seams were about 1000m below the surface and at a temperature of between 70 and 80°C, at a time when the Basin was rapidly subsiding. These early illites were stable and retained their 1M polytype even after being exposed to temperatures of 150-190°C during maximum burial in the southeastern Bowen Basin. The second phase of illitization (at 232 ± 3) occurred at about the time of maximum burial. The latest phase took place between 223 ± 3 and 212 ± 3 Ma ago and occurred in a wider temperature range (between 170 and 100°C) during a rapid uplift in the Late Triassic. The Bowen Basin area experienced a second cycle of subsidence that commenced in the Early Jurassic with the formation of the Surat Basin, which overlies the Bowen Basin and forms part of the Great Artesian Basin system. Regional uplift and erosion in middle Cretaceous times terminated sediment accumulation in the Surat Basin. During the second cycle of burial widespread carbonate mineralization in butt-cleats and joints took place. Calcite fluid inclusions indicate that calcite was precipitated from meteoric water at about 80°C. The widespread carbonate mineralization in butt cleats and the near-absence of carbonates in the face cleats is here attributed to permeability anisotropy, caused by a change in the direction of lateral compressive stress during Jurassic-Cretaceous times relative to that during the Triassic Hunter-Bowen Orogeny.
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Cleat mineralization of Upper Permian Baralaba/Rangal Coal Measures, Bowen Basin, Australia
Geological Society London Special Publications, 1996Co-Authors: Basim S M Faraj, Christopher R Fielding, Ian D R MackinnonAbstract:Coals from the Permo-Triassic Bowen Basin have been investigated using a variety of complementary analytical techniques. Face cleat minerals in the studied samples are dominated by authigenic clays, notably pure illite or illite-chlorite mixtures. Butt cleats and joints are dominated by carbonates, mostly calcite with less abundant ferroan calcite, ankerite and siderite. K/Ar ages of cleat-fill illites and one fracture illite-smectite fill indicate three phases of illite formation during the Triassic: (1) an early phase with ages clustered around 244 Ma ago; (2) a second phase about 232 Ma ago; and (3) the latest phase about 219 Ma ago. Thermal modelling of selected boreholes from the study area and other geological data indicate that the first phase of illitization occurred when the coal seams were about 1000m below the surface and at a temperature of between 70 and 80°C, at a time when the Basin was rapidly subsiding. These early illites were stable and retained their 1M polytype even after being exposed to temperatures of 150-190°C during maximum burial in the southeastern Bowen Basin. The second phase of illitization (at 232 ± 3) occurred at about the time of maximum burial. The latest phase took place between 223 ± 3 and 212 ± 3 Ma ago and occurred in a wider temperature range (between 170 and 100°C) during a rapid uplift in the Late Triassic. The Bowen Basin area experienced a second cycle of subsidence that commenced in the Early Jurassic with the formation of the Surat Basin, which overlies the Bowen Basin and forms part of the Great Artesian Basin system. Regional uplift and erosion in middle Cretaceous times terminated sediment accumulation in the Surat Basin. During the second cycle of burial widespread carbonate mineralization in butt-cleats and joints took place. Calcite fluid inclusions indicate that calcite was precipitated from meteoric water at about 80°C. The widespread carbonate mineralization in butt cleats and the near-absence of carbonates in the face cleats is here attributed to permeability anisotropy, caused by a change in the direction of lateral compressive stress during Jurassic-Cretaceous times relative to that during the Triassic Hunter-Bowen Orogeny.
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permian evolution of sandstone composition in a complex back arc extensional to foreland Basin the Bowen Basin eastern australia
Journal of Sedimentary Research, 1993Co-Authors: Julian C Baker, Christopher R Fielding, Patrice De Caritat, Melville M WilkinsonAbstract:ABSTRACT The Bowen Basin is a Permo-Triassic, back-arc extensional to foreland Basin that developed landward of an intermittently active continental volcanic arc associated with the eastern Australian convergent plate margin. The Basin has a complex, polyphase tectonic history that began with limited back-arc crustal extension daring the Early Permian. This created a series of north-trending grabens and half grabens which, in the west, accommodated quartz-rich sediment derived locally from surrounding uplifted continental basement. In the east, coeval calc-alkaline, volcanolithic-rich, and volcaniclastic sediment was derived from the active volcanic arc. This early extensional episode was followed by a phase of passive thermal subsidence accompanied by episodic compression during the late Early Permian to early Late Permian, with little contemporaneous volcanism. In the west, quartzose sediment was shed from stable, polymictic, continental basement immediately to the west and south of the Basin, whereas volcanolithic-rich sediment that entered the eastern side of the Basin during this time was presumably derived from the inactive, and possibly partly submerged, volcanic arc. During the late Late Permian, flexural loading and increased compression occurred along the eastern margin of the Bowen Basin, and renewed volcanism took place in the arc system to the east. Reactivation of this arc led to westward and southward spread of volcanolithic-rich sediment over the entire Basin. Accordingly, areas in the west that were earlier receiving quartzose, craton-derived sediment from the west and south were overwhelmed by volcanolithic-rich, arc-derived sediment from the east and north. This transition from quartz-rich, craton-derived sediments to volcanolithic-rich, arc-derived sediments is consistent with the interpreted back-arc extensional to foreland Basin origin for the Bowen Basin.