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Kliti Grice - One of the best experts on this subject based on the ideXlab platform.
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extent and persistence of photic zone euxinia in middle late devonian seas insights from the Canning Basin and implications for petroleum source rock formation
Marine and Petroleum Geology, 2018Co-Authors: Gemma Spaak, Roger E Summons, Dianne S Edwards, Heidi J Allen, Hendrik Grotheer, Marco J L Coolen, Kliti GriceAbstract:Abstract Late Devonian mass extinctions attributed to extensive anoxia and/or euxinia of the oceans are associated with widespread deposition of organic-rich shales. Also in the epeiric waters of the Canning Basin (Western Australia), photic zone euxinia (PZE) prevailed during the Givetian–Frasnian, with geochemical evidence for PZE on the northern (Lennard Shelf)–, and southern (Barbwire Terrace) margins of the Fitzroy Trough. On the Lennard Shelf, shales record episodic pulses of PZE associated with high algal activity due to enhanced nutrient supply, whereas a restricted marine setting on the Barbwire Terrace is thought to be the main driver for the development of persistent PZE and associated bacterial predominance. Structural evidence indicates that the Fitzroy Trough was a confined Basin during the Late Devonian with the possibility of limited ocean circulation. Widespread PZE is expected to have developed in the poorly mixed water column, if the Basin received sufficient nutrient supply for enhanced primary production. Notwithstanding the presence of anoxia during deposition of potential source rocks, only two small Devonian-sourced oil fields and numerous oil shows have been found in the Canning Basin. Biomarker assemblages show that the oils produced from the Lennard Shelf fields (i.e. Blina-1, Blina-4 and Janpam North-1) have substantially different molecular compositions to the minor oil recovered from Mirbelia-1 on the Barbwire Terrace. A correlation was established between the Lennard Shelf oils and rock extracts from the Gogo Formation at Blina-1 and McWhae Ridge-1 based on their hopane, sterane and carotenoids abundances. A definitive source correlation was not obtained for the Mirbelia-1 oil, but it did show some genetic affinity to the Givetian–Frasnian extracts from the Barbwire Terrace, suggesting that local source rocks are developed in the region.
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environmental conditions and microbial community structure during the great ordovician biodiversification event a multi disciplinary study from the Canning Basin western australia
Global and Planetary Change, 2017Co-Authors: Gemma Spaak, Roger E Summons, Dianne S Edwards, Clinton B Foster, Anais Pages, Neil Sherwood, Kliti GriceAbstract:Abstract The Great Ordovician Biodiversification Event (GOBE) is regarded as one of the most significant evolutionary events in the history of Phanerozoic life. The present study integrates palynological, petrographic, molecular and stable isotopic (δ13C of biomarkers) analyses of cores from four boreholes that intersected the Goldwyer Formation, Canning Basin, Western Australia, to determine depositional environments and microbial diversity within a Middle Ordovician epicontinental, tropical sea. Data from this study indicate lateral and temporal variations in lipid biomarker assemblages extracted from Goldwyer Formation rock samples. These variations likely reflect changing redox conditions between the upper (Unit 4) and lower (Units 1 + 2) Goldwyer, which is largely consistent with existing depositional models for the Goldwyer Formation. Cryptospores were identified in Unit 4 in the Theia-1 well and are most likely derived from bryophyte-like plants, making this is the oldest record of land plants in Australian Middle Ordovician strata. Biomarkers in several samples from Unit 4 that also support derivation from terrestrial organic matter include benzonaphthofurans and δ13C-depleted mid-chain n-alkanes. Typical Ordovician marine organisms including acritarchs, chitinozoans, conodonts and graptolites were present in the lower and upper Goldwyer Formation, whereas the enigmatic organism Gloeocapsomorpha prisca (G. prisca) was only detected in Unit 4. The correlation of a strong G. prisca biosignature with high 3-methylhopane indices and 13C depleted G. prisca–derived chemical fossils (biomarkers) is interpreted to suggest an ecological relationship between methanotrophs and G. prisca. This research contributes to a greater understanding of Ordovician marine environments from a molecular perspective since few biomarker studies have been undertaken on age-equivalent sections. Furthermore, the identification of the oldest cryptospores in Australia and their corresponding terrestrial biomarkers provides further insight into the geographical distribution and evolution of early land plants.
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mudstones and embedded concretions show differences in lithology related but not source related biomarker distributions
Organic Geochemistry, 2017Co-Authors: Sabine K Lengger, Ines Melendez, Roger E Summons, Kliti GriceAbstract:Abstract The mudstones of the Western Australian Gogo Formation harbour numerous carbonate concretions which often contain preserved fossils of Lagerstatte-like quality. These are especially notable in places where the mudstone has eroded, giving way to nodule fields, which afford valuable paleobiological records. It is, however, a challenge to determine their paleoenvironmental context. Here, we analysed concretions from a core drilled in the Canning Basin Gogo Formation. At two different depths, concretions were compared to the surrounding mudstone found at the same depth. Electron microscopy and X-ray spectroscopy showed that the concretions were carbonate-rich and contained detrital fragments. Biomarker data showed that mudstone and concretions had very similar distributions and presented marine biosignatures including indicators of anoxic depositional conditions, a stratified water column, and photic zone euxinia. The concretions contained higher amounts of C 27 steranes, indicating that more labile organic matter such as animal remains could have triggered concretion formation. Statistical analyses of the results showed that concretions and shales differed ( p p 31 homohopanes, and hopane/sterane ratios ( p
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changes of palaeoenvironmental conditions recorded in late devonian reef systems from the Canning Basin western australia a biomarker and stable isotope approach
Gondwana Research, 2015Co-Authors: Svenja Tulipani, Peter W. Haines, Roger E Summons, Kliti Grice, Paul F. Greenwood, Peter E Sauer, Arndt Schimmelmann, Clinton B Foster, Michael E Bottcher, Ted PlaytonAbstract:Abstract Although the Late Devonian extinctions were amongst the largest mass extinction events in the Phanerozoic, the causes, nature and timing of these events remain poorly restrained. In addition to the most pronounced biodiversity loss at the Frasnian–Famennian (F–F) boundary and the end Famennian, there were also less extensively studied extinction pulses in the Middle to Late Givetian and the Frasnian. Here we used a combination of palynological, elemental, molecular and stable isotope analyses to investigate a sedimentary record of reef-systems from this time period in the Canning Basin, Western Australia. The acquired data generally showed distinct variations between sediments from (i) the time around the Givetian–Frasnian (G–F) boundary and (ii) later in the Frasnian and indicated a distinct interval of biotic stress, particularly for reef-builders, in the older sediments. Alterations of pristane/phytane ratios, gammacerane indices, Chlorobi biomarkers, δDkerogen and chroman ratios describe the change from a restricted marine palaeoenvironment with an anoxic/euxinic hypolimnion towards a presumably open marine setting with a vertically mixed oxic to suboxic water column. Simultaneous excursions in δ13C profiles of carbonates, organic matter (OM) and hydrocarbons in the older sediments reflect the stratification-induced enhancement of OM-recycling by sulfate reducing bacteria. Alterations in sterane distributions and elevated abundances of methyltrimethyltridecylchromans (MTTCs) and perylene indicate an increased terrigenous nutrient input via riverine influx, which would have promoted stratification, phytoplankton blooms and the development of lower water column anoxia. The detected palaeoenvironmental conditions around the G–F boundary may reflect a local or global extinction event. Our data furthermore suggest a contribution of the higher plant-expansion and photic zone euxinia to the Late Devonian extinctions, consistent with previous hypotheses. Furthermore, this work might contribute to the understanding of variations in Devonian reef margin and platform-top architecture, relevant for petroleum exploration and development in the global Devonian hydrocarbon resources.
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Biomarkers reveal the role of photic zone euxinia in exceptional fossil preservation: An organic geochemical perspective
Geology, 2013Co-Authors: Ines Melendez, Kliti Grice, Kate Trinajstic, Mojgan Ladjavardi, Paul F. Greenwood, Katharine ThompsonAbstract:Photic zone euxinia (PZE) has proven important for elucidating biogeochemical changes that occur during oceanic anoxic events, including mass extinction and conditions associated with unique fossil preservation. Organic geochemical analyses of a 380 Ma invertebrate fossil, which included well-preserved soft tissues, from the Gogo Formation (Canning Basin, Western Australia) showed biomarkers and stable isotopic values characteristic of PZE and a consortium of sulfate-reducing bacteria, which lead to exceptional fossil and biomarker preservation. The carbonate concretion contained phytoplankton, green sulfur bacteria (Chlorobi), and sulfate-reducing bacteria biomarkers with an increasing concentration toward the nucleus where the fossil is preserved. The spatial distribution of cholestane unequivocally associated with the fossilized tissue and its high relative abundance to the total steranes suggest that the fossil is a crustacean. The presence of an active sulfur cycle in this Devonian system, including sulfate reduction and the resulting PZE, played a pivotal role in the preservation of soft tissue from the fossil and its associated low-maturity biomarker ratios.
Ted Playton - One of the best experts on this subject based on the ideXlab platform.
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Using elemental chemostratigraphy on Mid-Late Frasnian platform-top successions from the Lennard Shelf outcrops, Canning Basin, Western Australia.
New Advances in Devonian Carbonates: Outcrop Analogs Reservoirs and Chronostratigraphy, 2017Co-Authors: Kenneth T. Ratcliffe, Ted Playton, Samuel Caulfield-kerney, Roger M. Hocking, Peter W. Haines, David Wray, Eric Tohver, Paul Montgomery, Joseph L KirschvinkAbstract:High-resolution chronostratigraphic correlation using elemental chemostratigraphy in platform carbonates is typically difficult to achieve. Here, elemental chemostratigraphy is used to correlate between two platform-top, carbonate-dominated field sections from the narrow Lennard Shelf that existed on the NE margin of the Canning Basin, Western Australia, during the mid–late Frasnian. The correlation, constrained by magnetic polarity reversals and physical ground truthing, is based on recognition of distinctive cyclical ‘‘stacking patterns’’ defined by changes in concentrations of the trace element zirconium (Zr). Zr concentrations are controlled by the amount of the heavy mineral zircon in the sediments, which is derived from a terrigenous source and is diagenetically very stable. The stacking patterns in the lower part of the study sections display gradually upward-increasing values of Zr to a maximum, followed by an almost immediate fall to a minimum. In the upper part of the study interval, the cycles are more symmetrical, with both gradually increasing and decreasing portions. The point at which the change in Zr stacking pattern occurs in the two sections is synchronous and occurs in association with a supersequence maximum flooding surface. The correlation based on maximum and minimum Zr values throughout the two sections is demonstrated to be chronostratigraphic by comparison with correlations based upon paleomagnetism and physical ground truthing. When element ratios commonly used as provenance and paleoclimate proxies are plotted, the variations between closely spaced samples are greater than any systematic variations throughout the study intervals. Therefore, no isochemical chemozones can be defined, implying that during deposition of the study intervals, there were no long-lived changes in sediment provenance or paleoclimate that the elemental chemistry can detect. The work presented here shows that the standard approach of defining isochemical chemozones for chemostratigraphic correlation is not always appropriate. However, an approach using cyclical changes in elemental variables for chemostratigraphic correlation between two closely spaced sections is chronostratigraphically valid. The greater challenge is in application of the same approach to more widely spaced sections, potentially in different facies of a carbonate setting.
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changes of palaeoenvironmental conditions recorded in late devonian reef systems from the Canning Basin western australia a biomarker and stable isotope approach
Gondwana Research, 2015Co-Authors: Svenja Tulipani, Peter W. Haines, Roger E Summons, Kliti Grice, Paul F. Greenwood, Peter E Sauer, Arndt Schimmelmann, Clinton B Foster, Michael E Bottcher, Ted PlaytonAbstract:Abstract Although the Late Devonian extinctions were amongst the largest mass extinction events in the Phanerozoic, the causes, nature and timing of these events remain poorly restrained. In addition to the most pronounced biodiversity loss at the Frasnian–Famennian (F–F) boundary and the end Famennian, there were also less extensively studied extinction pulses in the Middle to Late Givetian and the Frasnian. Here we used a combination of palynological, elemental, molecular and stable isotope analyses to investigate a sedimentary record of reef-systems from this time period in the Canning Basin, Western Australia. The acquired data generally showed distinct variations between sediments from (i) the time around the Givetian–Frasnian (G–F) boundary and (ii) later in the Frasnian and indicated a distinct interval of biotic stress, particularly for reef-builders, in the older sediments. Alterations of pristane/phytane ratios, gammacerane indices, Chlorobi biomarkers, δDkerogen and chroman ratios describe the change from a restricted marine palaeoenvironment with an anoxic/euxinic hypolimnion towards a presumably open marine setting with a vertically mixed oxic to suboxic water column. Simultaneous excursions in δ13C profiles of carbonates, organic matter (OM) and hydrocarbons in the older sediments reflect the stratification-induced enhancement of OM-recycling by sulfate reducing bacteria. Alterations in sterane distributions and elevated abundances of methyltrimethyltridecylchromans (MTTCs) and perylene indicate an increased terrigenous nutrient input via riverine influx, which would have promoted stratification, phytoplankton blooms and the development of lower water column anoxia. The detected palaeoenvironmental conditions around the G–F boundary may reflect a local or global extinction event. Our data furthermore suggest a contribution of the higher plant-expansion and photic zone euxinia to the Late Devonian extinctions, consistent with previous hypotheses. Furthermore, this work might contribute to the understanding of variations in Devonian reef margin and platform-top architecture, relevant for petroleum exploration and development in the global Devonian hydrocarbon resources.
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upper kellwasser carbon isotope excursion pre dates the f f boundary in the upper devonian lennard shelf carbonate system Canning Basin western australia
Palaeogeography Palaeoclimatology Palaeoecology, 2015Co-Authors: Kelly Hillbun, Ted Playton, Peter W. Haines, David Wray, Eric Tohver, Kate Trinajstic, Brett Roelofs, Ken Ratcliffe, Samuel Caulfieldkerney, Roger M. HockingAbstract:Abstract Here we report four high-resolution carbon isotope records in addition to trace element data for the Frasnian–Famennian (F–F) boundary interval in the Lennard Shelf carbonate system of the Canning Basin, Western Australia. This region lacks the characteristic black shale horizons associated with the global Late Devonian Kellwasser extinction events, yet still exhibits a trend in carbon isotope character similar to what has been reported from elsewhere in the world (two positive δ13C excursions with ~ 3–4‰ amplitudes). Enrichments in select trace element ratios suggest that both excursions are related to periods of oxygen deprivation and perhaps increased biological productivity. Given the continuous and stratigraphically expanded nature of Lennard Shelf sections, together with high-density sampling constrained by both conodont biostratigraphy and magnetostratigraphy, we observe that the Upper Kellwasser isotope excursion (maximum δ13C values) and associated trace element enrichments occur distinctly lower than the F–F boundary level. These results have implications for the paleoenvironmental conditions leading up to the Late Devonian Mass Extinction in terms of ocean chemistry and circulation patterns. This data set allows for a rare, detailed look at the temporal relationship between the Kellwasser events and the F–F boundary and constrains the pattern of carbon isotope perturbations at the intra-zonal scale.
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late devonian carbonate margins and foreslopes of the lennard shelf Canning Basin western australia part b development during progradation and across the frasnian famennian biotic crisis
Journal of Sedimentary Research, 2015Co-Authors: Ted Playton, Charles KeransAbstract:Abstract Many studies document the occurrence of carbonate progradational successions that are driven by overall accommodation-limited conditions and represent periods when substantial volumes of sediment are stored in slope settings. However, few have reported on the detailed internal anatomy and components of prograding clinothems, and furthermore, little is known about how environmental parameters affect the development of carbonate margins and slopes when superimposed on the long-term, low-accommodation signal. Upper Devonian (Frasnian and Famennian) carbonate outcrop exposures along the Lennard Shelf, northeast Canning Basin, Western Australia, offer the examination of reefal margin and foreslope development in a variety of settings, one of which is long-term (> 10 Ma) progradation during the late Frasnian and Famennian. In the early phases of progradation, a global biotic crisis and faunal overturn occurred around the Frasnian–Famennian (F-F) boundary, and indications of global climatic cooling are interpreted at points throughout the Late Devonian. These extrinsic and intrinsic controls provide ecologic context and a stratigraphic framework to assess carbonate margin and foreslope architectures and facies distributions in order to better characterize and predict their complex heterogeneity. The outcrop dataset collected includes measured sections tied to interpreted photomosaics and detailed mapping using aerial photographs from the South Lawford Range, Windjana Gorge, and Dingo Gap areas. The outcrop observations highlight distinctive changes in margin style, foreslope composition, stratigraphic packaging, and strike variability within the contexts of the F-F biotic crisis, long-term highstand (HST) progradation, and Late Devonian climatic changes. Intervals before and after the F-F boundary exhibit notable increases in downslope calcimicrobial boundstone encrustation and evidence for waning foreslope contributions from other, previously flourishing, carbonate factories, reflecting stressed ecological conditions and consequent calcimicrobial opportunism during gradual buildup and recovery periods that bracket the extinction. The Famennian slope (post-effects related to the F-F crisis) can be subdivided into a calcimicrobial boundstone-dominated upper slope with a highly complex downdip transition into a mixed debris- and grain-dominated middle slope, and a silt-dominated lower slope to toe of slope, and exhibits a highly complex lateral heterogeneity associated with multiple contributing sediment factories and temporal partitioning of resedimentation. A repeated stacking pattern is observable in the Famennian middle-slope setting, consisting of upward successions of debris followed by a gradation from silt-dominated deposits into grain-dominated deposits; we here interpret these as the expression of high-frequency sequences superimposed upon the longer-term progradation, and a function of transitional (greenhouse to icehouse) climates. These findings offer predictive relationships that link the internal depositional heterogeneity of prograding slope systems to the interplay of long-term accommodation drivers, ecological conditions affecting carbonate sediment factories, and climatic conditions that control the development of high-frequency sequences.
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late devonian carbonate margins and foreslopes of the lennard shelf Canning Basin western australia part a development during backstepping and the aggradation to progradation transition
Journal of Sedimentary Research, 2015Co-Authors: Ted Playton, Charles KeransAbstract:Abstract Carbonate reefal margin and foreslope settings are characteristically heterogeneous and difficult to predict due to a spectrum of sediment source factories, resedimentation processes, resultant deposit types, and controlling parameters. In particular, the effects of changes in long-term accommodation on the composition, architecture, and sediment distribution patterns of carbonate margin–foreslope–Basin systems are poorly understood. Upper Devonian (Frasnian) outcrop exposures along the Lennard Shelf, northeast Canning Basin, Western Australia, were investigated to assess the development of reefal margin and foreslope settings during long-term 1) platform backstepping with aggradational pulses, and 2) across the transition from platform aggradation to progradation. Measured sections tied to interpreted photomosaics and detailed mapping using aerial photographs were collected from the South Lawford Range and Windjana Gorge areas. The exposures reveal distinctive differences in foreslope grain composition, deposit characteristics and proportions, margin morphology, and stratigraphic expression 1) during platform evolution between backstepping events, and 2) depending on position within the long-term accommodation setting. Between backstepping events, aggradational margins can be classified as “growth escarpments” with associated grain-dominated, onlapping foreslope deposits. Margins across the long-term transition from aggradation to progradation evolved from erosional escarpments with onlapping debris deposits to accretionary, interfingering configurations. Development of growth escarpments between backstepping events was a function of vertical reefal growth from sustained high accommodation conditions during the long-term transgressive systems tract, coupled with a Frasnian reefal assemblage that responded to light and tracked relative sea level. This net vertical reefal growth also resulted in relative margin stability and the deposition of grain-dominated foreslopes. Conversely, margins were highly unstable and underwent repeated failure across the long-term aggradation-to-progradation transition, reflecting a lack of underlying substrate to support Basinward advance, and resulting in debris-dominated foreslopes. These observations provide relationships that predict margin and foreslope associations of facies-scale heterogeneity and seismic-scale geometry within a low-frequency sequence stratigraphic framework.
Kenneth J. Mcnamara - One of the best experts on this subject based on the ideXlab platform.
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patterns of evolution and extinction in proetid trilobites during the late devonian mass extinction event Canning Basin western australia
Palaeontology, 2013Co-Authors: Raimund Feist, Kenneth J. McnamaraAbstract:In the early Late Devonian, terminal Frasnian proetid trilobites have previously only been known from Europe and North Africa. For the first time, a rich fauna of late Frasnian proetids is described from the Virgin Hills Formation, Canning Basin, Western Australia. Seventeen species in six genera are described, of which three are new: Rudybole gen. nov., Palpebralina gen. nov. and Canningbole gen. nov. A new subgenus, Chlupaciparia (Australoparia) subgen. nov. is also described. Fourteen of the species are new: Palpebralia initialis sp. nov., P. pustulata sp. nov., ?P. sp. nov. A, Rudybole depressa sp. nov., Palpebralina pseudopalpebralis sp. nov. (comprising the subspecies P. pseudopalpebralis pseudopalpebralis subsp. nov. and P. pseudopalpebralis ultima subsp. nov.), P. minor sp. nov., P. ocellifer sp. nov., Canningbole latimargo sp. nov., C. henwoodorum sp. nov., C. macromma sp. nov., Pteroparia extrema sp. nov., Chlupaciparia (Chlupaciparia) planiops sp. nov., Chlupaciparia (Australoparia) australis sp. nov. and C. (Australoparia) lata sp. nov. The subspecies Rudybole adorfensis angusta subsp. nov. is also described. The proetids range through conodont Zones 11–13b and terminate at the Upper Kellwasser Event, which marks the terminal Frasnian mass extinction event. Three of the six proetid lineages, Palpebralia, Canningbole and Pteroparia, show evolutionary trends of eye reduction. Two of the remaining lineages, Rudybole and Palpebralina, consist exclusively of blind taxa. The last, Chlupaciparia, also comprises forms with reduced eyes. The proetids show a stepped pattern of extinction during the late Frasnian, which correlate with two Kellwasser biocrises documented in European/North African Frasnian sections. The highest diversity preceded the Lower Kellwasser event that occurred at the end of conodont Zone 12 and saw the extinction of all species present in that zone. However, only one genus, Pteroparia, locally became extinct. A major higher-level taxonomic mass extinction at the top of Zone 13b initiated the Upper Kellwasser extinction event. This included extinction at the generic level, with all five remaining genera becoming extinct, and at the family level, with the loss of the Tropidocoryphidae.
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patterns of extinction and recovery of phacopid trilobites during the frasnian famennian late devonian mass extinction event Canning Basin western australia
Geological Magazine, 2009Co-Authors: Raimund Feist, Kenneth J. Mcnamara, Catherine Cronier, Rudy LeroseyaubrilAbstract:A diverse fauna of phacopid trilobites is described from the Late Devonian (middle Frasnian to early Famennian) of the northern Canning Basin, Western Australia. One new genus and four species in two genera are described from zones 11, 13a and 13b of the middle and late Frasnian: Trimerocephaloides sinevisus gen. nov. and sp. nov., T. ? linguiformis sp. nov., Acuticryphops acuticeps (Kayser, 1889) and A. klapperi sp. nov. Late Frasnian phacopines are either blind, as shown for the first time in Trimerocephaloides sinevisus, or show trends to decreasing eye size up to the Frasnian-Famennian 'Kellwasser' mass extinction event. This evolutionary trend in Acuticryphops is demonstrated to have been global at this time. One new genus and six species of early Famennian phacopids are described, from the Upper triangularis, crepida and rhomboidea zones: Houseops gen. nov. with the new taxa H. Canningensis sp. nov., H. beckeri sp. nov. and H. sp. A, Babinops planiventer Feist & Becker, 1997, B. minor sp. nov., Trimerocephalus tardispinosus Feist & Becker, 1997 and T. mimbi sp. nov. In contrast to European sections where exclusively blind phacopids are known in earliest Famennian sites, initial recovery following the mass extinction event in Canning peri-reefal environments is characterized by oculated forms. These trilobites must have evolved from conservative ancestors with normal eyes that had succeeded in surviving the Kellwasser biocrises in reef-related shallow water niches. Thus the origin of post-event phacopids from shallow water environments is demonstrated for the first time. Descendant lineages show increasing eye size, increased cephalic vaulting and effacement during the early Famennian. Of the five orders of trilobites that are present during the Frasnian Stage at the beginning of the Late Devonian, only two, the Proetida and the Phacopida, survived into the Famennian. The presence of a conformable sequence of trilobite-bearing fore-reef limestones, the Virgin Hills Formation, that form part of the Late Devonian reef system in the northern part of the Canning Basin in Western Australia, allows the patterns of evolution and extinction of the late Frasnian and early Famennian trilobites to be assessed. In these deposits the three orders that became extinct during the Frasnian-Famennian biocrises were the Corynexochida (McNamara & Feist, 2006), the Lichida (Feist & McNamara, 2007) and the Harpetida (McNamara, Feist & Ebach, in press). Here we focus on one of the groups that survived this event, the Phacopida. Although, with a single exception, they are rare elements of the trilobite fauna in the Canning Basin, the phacopids are generically the most diverse of the
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doi:10.1017/S0016756808005335 Printed in the United Kingdom Patterns of extinction and recovery of phacopid trilobites during the Frasnian–Famennian (Late Devonian) mass extinction event,
2008Co-Authors: Raimund Feist, Kenneth J. Mcnamara, Rudy Lerosey-aubrilAbstract:Abstract – A diverse fauna of phacopid trilobites is described from the Late Devonian (middle Frasnian to early Famennian) of the northern Canning Basin, Western Australia. One new genus and four species in two genera are described from zones 11, 13a and 13b of the middle and late Frasnian: Trimerocephaloides sinevisus gen. nov. and sp. nov., T.? linguiformis sp. nov., Acuticryphops acuticeps (Kayser, 1889) and A. klapperi sp. nov. Late Frasnian phacopines are either blind, as shown for the first time in Trimerocephaloides sinevisus, or show trends to decreasing eye size up to the Frasnian–Famennian ‘Kellwasser ’ mass extinction event. This evolutionary trend in Acuticryphops is demonstrated to have been global at this time. One new genus and six species of early Famennian phacopids are described, from the Upper triangularis, crepida and rhomboidea zones: Houseops gen
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New styginids from the Late Devonian of Western Australia - The last corynexochid trilobites
Journal of Paleontology, 2006Co-Authors: Kenneth J. Mcnamara, Raimund FeistAbstract:Two new species of scutelluine styginid trilobites are described from Frasnian strata in the Virgin Hills Formation in the Canning Basin of Western Australia. They are placed in the genus Telopeltis n. gen., reflecting the fact that their final occurrence in the late Frasnian, up to the latest Frasnian Kellwasser extinction event, is the last known record of scutelluine trilobites. As such, it also represents the youngest record of the order Corynexochida. The two species, Telopeltis woodwardi n. sp. and Telopeltis microphthalmus n. sp., are unlike most other scutelluines in possessing extremely vaulted pygidia and showing trends to eye reduction. Such eye reduction is a common feature of late Frasnian trilobites. The characteristic morphological features of this small genus are indicative of evolution of this last scutelluine by paedomorphosis.
Peter W. Haines - One of the best experts on this subject based on the ideXlab platform.
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Using elemental chemostratigraphy on Mid-Late Frasnian platform-top successions from the Lennard Shelf outcrops, Canning Basin, Western Australia.
New Advances in Devonian Carbonates: Outcrop Analogs Reservoirs and Chronostratigraphy, 2017Co-Authors: Kenneth T. Ratcliffe, Ted Playton, Samuel Caulfield-kerney, Roger M. Hocking, Peter W. Haines, David Wray, Eric Tohver, Paul Montgomery, Joseph L KirschvinkAbstract:High-resolution chronostratigraphic correlation using elemental chemostratigraphy in platform carbonates is typically difficult to achieve. Here, elemental chemostratigraphy is used to correlate between two platform-top, carbonate-dominated field sections from the narrow Lennard Shelf that existed on the NE margin of the Canning Basin, Western Australia, during the mid–late Frasnian. The correlation, constrained by magnetic polarity reversals and physical ground truthing, is based on recognition of distinctive cyclical ‘‘stacking patterns’’ defined by changes in concentrations of the trace element zirconium (Zr). Zr concentrations are controlled by the amount of the heavy mineral zircon in the sediments, which is derived from a terrigenous source and is diagenetically very stable. The stacking patterns in the lower part of the study sections display gradually upward-increasing values of Zr to a maximum, followed by an almost immediate fall to a minimum. In the upper part of the study interval, the cycles are more symmetrical, with both gradually increasing and decreasing portions. The point at which the change in Zr stacking pattern occurs in the two sections is synchronous and occurs in association with a supersequence maximum flooding surface. The correlation based on maximum and minimum Zr values throughout the two sections is demonstrated to be chronostratigraphic by comparison with correlations based upon paleomagnetism and physical ground truthing. When element ratios commonly used as provenance and paleoclimate proxies are plotted, the variations between closely spaced samples are greater than any systematic variations throughout the study intervals. Therefore, no isochemical chemozones can be defined, implying that during deposition of the study intervals, there were no long-lived changes in sediment provenance or paleoclimate that the elemental chemistry can detect. The work presented here shows that the standard approach of defining isochemical chemozones for chemostratigraphic correlation is not always appropriate. However, an approach using cyclical changes in elemental variables for chemostratigraphic correlation between two closely spaced sections is chronostratigraphically valid. The greater challenge is in application of the same approach to more widely spaced sections, potentially in different facies of a carbonate setting.
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changes of palaeoenvironmental conditions recorded in late devonian reef systems from the Canning Basin western australia a biomarker and stable isotope approach
Gondwana Research, 2015Co-Authors: Svenja Tulipani, Peter W. Haines, Roger E Summons, Kliti Grice, Paul F. Greenwood, Peter E Sauer, Arndt Schimmelmann, Clinton B Foster, Michael E Bottcher, Ted PlaytonAbstract:Abstract Although the Late Devonian extinctions were amongst the largest mass extinction events in the Phanerozoic, the causes, nature and timing of these events remain poorly restrained. In addition to the most pronounced biodiversity loss at the Frasnian–Famennian (F–F) boundary and the end Famennian, there were also less extensively studied extinction pulses in the Middle to Late Givetian and the Frasnian. Here we used a combination of palynological, elemental, molecular and stable isotope analyses to investigate a sedimentary record of reef-systems from this time period in the Canning Basin, Western Australia. The acquired data generally showed distinct variations between sediments from (i) the time around the Givetian–Frasnian (G–F) boundary and (ii) later in the Frasnian and indicated a distinct interval of biotic stress, particularly for reef-builders, in the older sediments. Alterations of pristane/phytane ratios, gammacerane indices, Chlorobi biomarkers, δDkerogen and chroman ratios describe the change from a restricted marine palaeoenvironment with an anoxic/euxinic hypolimnion towards a presumably open marine setting with a vertically mixed oxic to suboxic water column. Simultaneous excursions in δ13C profiles of carbonates, organic matter (OM) and hydrocarbons in the older sediments reflect the stratification-induced enhancement of OM-recycling by sulfate reducing bacteria. Alterations in sterane distributions and elevated abundances of methyltrimethyltridecylchromans (MTTCs) and perylene indicate an increased terrigenous nutrient input via riverine influx, which would have promoted stratification, phytoplankton blooms and the development of lower water column anoxia. The detected palaeoenvironmental conditions around the G–F boundary may reflect a local or global extinction event. Our data furthermore suggest a contribution of the higher plant-expansion and photic zone euxinia to the Late Devonian extinctions, consistent with previous hypotheses. Furthermore, this work might contribute to the understanding of variations in Devonian reef margin and platform-top architecture, relevant for petroleum exploration and development in the global Devonian hydrocarbon resources.
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upper kellwasser carbon isotope excursion pre dates the f f boundary in the upper devonian lennard shelf carbonate system Canning Basin western australia
Palaeogeography Palaeoclimatology Palaeoecology, 2015Co-Authors: Kelly Hillbun, Ted Playton, Peter W. Haines, David Wray, Eric Tohver, Kate Trinajstic, Brett Roelofs, Ken Ratcliffe, Samuel Caulfieldkerney, Roger M. HockingAbstract:Abstract Here we report four high-resolution carbon isotope records in addition to trace element data for the Frasnian–Famennian (F–F) boundary interval in the Lennard Shelf carbonate system of the Canning Basin, Western Australia. This region lacks the characteristic black shale horizons associated with the global Late Devonian Kellwasser extinction events, yet still exhibits a trend in carbon isotope character similar to what has been reported from elsewhere in the world (two positive δ13C excursions with ~ 3–4‰ amplitudes). Enrichments in select trace element ratios suggest that both excursions are related to periods of oxygen deprivation and perhaps increased biological productivity. Given the continuous and stratigraphically expanded nature of Lennard Shelf sections, together with high-density sampling constrained by both conodont biostratigraphy and magnetostratigraphy, we observe that the Upper Kellwasser isotope excursion (maximum δ13C values) and associated trace element enrichments occur distinctly lower than the F–F boundary level. These results have implications for the paleoenvironmental conditions leading up to the Late Devonian Mass Extinction in terms of ocean chemistry and circulation patterns. This data set allows for a rare, detailed look at the temporal relationship between the Kellwasser events and the F–F boundary and constrains the pattern of carbon isotope perturbations at the intra-zonal scale.
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Late Devonian carbonate magnetostratigraphy from the Oscar and Horse Spring Ranges, Lennard Shelf, Canning Basin, Western Australia
Earth and Planetary Science Letters, 2015Co-Authors: Jeroen Hansma, Ted Playton, Joseph L Kirschvink, Eric Tohver, Maodu Yan, Kate Trinajstic, Brett Roelofs, Sarah Peek, Sarah P. Slotznick, Peter W. HainesAbstract:a b s t r a c t The Late Devonian was a time of major evolutionary change encompassing the fifth largest mass extinction, the Frasnian-Famennian event. In order to establish a chronological framework for global correlation before, during, and following the Frasnian-Famennian mass extinction, we carried out a coupled magnetostratigraphic and biostratigraphic study of two stratigraphic sections in the Upper Devonian carbonate reef complexes of the Lennard Shelf, in the Canning Basin, Western Australia. Magnetostratigraphy from these rocks provides the first high-resolution definition of the Late Devonian magnetic polarity timescale. A 581-m-reference section and an 82-m overlapping section through the marginal slope facies (Napier Formation) of the Oscar Range as well as a 117-m section at Horse Spring (Virgin Hills Formation) were sampled at decimeter to meter scale for magnetostratigraphy. Conodont biostratigraphy was used to correlate both sections, and link magnetostratigraphic polarity zones to a globally established biostratigraphy. As table, Characteristic Remanent Magnetization (ChRM) with dual polarities (NE, shallowly upward and SW, shallowly downward) is recovered from ∼60% of all samples, with magnetite inferred to be the chief magnetic carrier from thermal demagnetization characteristics. These directions define a geomagnetic pole at 49.5 ◦ S/285.8 ◦ E and α95 = 2. 4( n = 501), placing the Canning Basin at 9.9 ◦ S during the Late Devonian, consistent with carbonate reef development at this time. Ac onservative interpretation of the magnetostratigraphy shows the recovery of multiple reversals from both sections, not including possible cryptochrons and short duration magnetozones. Field tests for primary remanence include positive reversal tests and matching magnetozones from an overlapping section in the Oscar Range. As trong correlation was found between magnetic polarity stratigraphies of the Oscar Range and Horse Spring sections, and we correlate 12 magnetostratigraphic packages. The relative stratigraphic thicknesses of the isochronous sediments from these two sections indicate that carbonate accumulation was ∼4.5× faster in the middle slope deposits at Oscar Range than in the more distal, lower slope Horse Spring deposits for the middle Frasnian through Famennian. The magnetic field during the Late Devonian underwent a relatively high reversal frequency with good potential for regional and global correlation, and should prove useful in deciphering a high-resolution chronostratigraphy across the Lennard Shelf to enable higher confidence examination of reef development across a major biotic crisis.
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upper kellwasser carbon isotope excursion pre dates the f f boundary in the upper devonian lennard shelf carbonate system Canning Basin western australia
Palaeogeography Palaeoclimatology Palaeoecology, 2015Co-Authors: Kelly Hillbun, Ted Playton, Peter W. Haines, David Wray, Eric Tohver, Kate Trinajstic, Brett Roelofs, Ken Ratcliffe, Samuel Caulfieldkerney, Roger M. HockingAbstract:Abstract Here we report four high-resolution carbon isotope records in addition to trace element data for the Frasnian–Famennian (F–F) boundary interval in the Lennard Shelf carbonate system of the Canning Basin, Western Australia. This region lacks the characteristic black shale horizons associated with the global Late Devonian Kellwasser extinction events, yet still exhibits a trend in carbon isotope character similar to what has been reported from elsewhere in the world (two positive δ13C excursions with ~ 3–4‰ amplitudes). Enrichments in select trace element ratios suggest that both excursions are related to periods of oxygen deprivation and perhaps increased biological productivity. Given the continuous and stratigraphically expanded nature of Lennard Shelf sections, together with high-density sampling constrained by both conodont biostratigraphy and magnetostratigraphy, we observe that the Upper Kellwasser isotope excursion (maximum δ13C values) and associated trace element enrichments occur distinctly lower than the F–F boundary level. These results have implications for the paleoenvironmental conditions leading up to the Late Devonian Mass Extinction in terms of ocean chemistry and circulation patterns. This data set allows for a rare, detailed look at the temporal relationship between the Kellwasser events and the F–F boundary and constrains the pattern of carbon isotope perturbations at the intra-zonal scale.
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Late Devonian carbonate magnetostratigraphy from the Oscar and Horse Spring Ranges, Lennard Shelf, Canning Basin, Western Australia
Earth and Planetary Science Letters, 2015Co-Authors: Jeroen Hansma, Ted Playton, Joseph L Kirschvink, Eric Tohver, Maodu Yan, Kate Trinajstic, Brett Roelofs, Sarah Peek, Sarah P. Slotznick, Peter W. HainesAbstract:a b s t r a c t The Late Devonian was a time of major evolutionary change encompassing the fifth largest mass extinction, the Frasnian-Famennian event. In order to establish a chronological framework for global correlation before, during, and following the Frasnian-Famennian mass extinction, we carried out a coupled magnetostratigraphic and biostratigraphic study of two stratigraphic sections in the Upper Devonian carbonate reef complexes of the Lennard Shelf, in the Canning Basin, Western Australia. Magnetostratigraphy from these rocks provides the first high-resolution definition of the Late Devonian magnetic polarity timescale. A 581-m-reference section and an 82-m overlapping section through the marginal slope facies (Napier Formation) of the Oscar Range as well as a 117-m section at Horse Spring (Virgin Hills Formation) were sampled at decimeter to meter scale for magnetostratigraphy. Conodont biostratigraphy was used to correlate both sections, and link magnetostratigraphic polarity zones to a globally established biostratigraphy. As table, Characteristic Remanent Magnetization (ChRM) with dual polarities (NE, shallowly upward and SW, shallowly downward) is recovered from ∼60% of all samples, with magnetite inferred to be the chief magnetic carrier from thermal demagnetization characteristics. These directions define a geomagnetic pole at 49.5 ◦ S/285.8 ◦ E and α95 = 2. 4( n = 501), placing the Canning Basin at 9.9 ◦ S during the Late Devonian, consistent with carbonate reef development at this time. Ac onservative interpretation of the magnetostratigraphy shows the recovery of multiple reversals from both sections, not including possible cryptochrons and short duration magnetozones. Field tests for primary remanence include positive reversal tests and matching magnetozones from an overlapping section in the Oscar Range. As trong correlation was found between magnetic polarity stratigraphies of the Oscar Range and Horse Spring sections, and we correlate 12 magnetostratigraphic packages. The relative stratigraphic thicknesses of the isochronous sediments from these two sections indicate that carbonate accumulation was ∼4.5× faster in the middle slope deposits at Oscar Range than in the more distal, lower slope Horse Spring deposits for the middle Frasnian through Famennian. The magnetic field during the Late Devonian underwent a relatively high reversal frequency with good potential for regional and global correlation, and should prove useful in deciphering a high-resolution chronostratigraphy across the Lennard Shelf to enable higher confidence examination of reef development across a major biotic crisis.
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Biomarkers reveal the role of photic zone euxinia in exceptional fossil preservation: An organic geochemical perspective
Geology, 2013Co-Authors: Ines Melendez, Kliti Grice, Kate Trinajstic, Mojgan Ladjavardi, Paul F. Greenwood, Katharine ThompsonAbstract:Photic zone euxinia (PZE) has proven important for elucidating biogeochemical changes that occur during oceanic anoxic events, including mass extinction and conditions associated with unique fossil preservation. Organic geochemical analyses of a 380 Ma invertebrate fossil, which included well-preserved soft tissues, from the Gogo Formation (Canning Basin, Western Australia) showed biomarkers and stable isotopic values characteristic of PZE and a consortium of sulfate-reducing bacteria, which lead to exceptional fossil and biomarker preservation. The carbonate concretion contained phytoplankton, green sulfur bacteria (Chlorobi), and sulfate-reducing bacteria biomarkers with an increasing concentration toward the nucleus where the fossil is preserved. The spatial distribution of cholestane unequivocally associated with the fossilized tissue and its high relative abundance to the total steranes suggest that the fossil is a crustacean. The presence of an active sulfur cycle in this Devonian system, including sulfate reduction and the resulting PZE, played a pivotal role in the preservation of soft tissue from the fossil and its associated low-maturity biomarker ratios.
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syndepositional fault control on lower frasnian platform evolution lennard shelf Canning Basin australia
Geology, 2009Co-Authors: Annette D George, Nancy Chow, Kate TrinajsticAbstract:Syndepositional faulting was a major control on internal platform stratigraphy in a Frasnian reef complex on the southeastern Lennard Shelf, northern Canning Basin, Australia. By combining platform (mostly backreef) facies distributions with key stratal surfaces and biostratigraphic data, we have developed a temporal framework for the Hull Range area. Platform evolution was controlled by normal faults via an initial tilt block geometry and subsequent differential subsidence and accommodation across the platform. Three third-order, flooding surface–bounded platform phases are recorded. Basal shallow marine siliciclastic facies were deposited in topographic lows adjacent to the hanging wall and close to internal faults. Early carbonate deposition in dominantly deep subtidal environments suggests an overall ramp-style setting that deepened toward the southeast. This phase is capped by a sequence boundary represented by multiple paleokarst surfaces in the northwest that pass laterally into a major flooding surface to the southeast, above which the platform expanded toward the Mount Elma–Painted Rocks fault system. The overall stacking pattern above the sequence boundary–flooding surface is aggradational to progradational with higher-frequency shoaling trends, and locally developed exposure surfaces, related to higher-order relative sea-level changes. This second phase of platform growth ended with major flooding and a pronounced backstep of the leeward margin.
