Journal articles: 'Sediments (Geology) Victoria'

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Holdgate, G. R., T. A. G. Smith, S. J. Gallagher, and M. W. Wallace. "Geology of coal-bearing Palaeogene sediments, onshore Torquay Basin, Victoria." Australian Journal of Earth Sciences 48, no. 5 (October 2001): 657. http://dx.doi.org/10.1046/j.1440-0952.2001.00888.x.

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Holdgate, G. R., T. A. G. Smith, S. J. Gallagher, and M. W. Wallace. "Geology of coal-bearing Palaeogene sediments, onshore Torquay Basin, Victoria." Australian Journal of Earth Sciences 48, no. 5 (October 2001): 657–79. http://dx.doi.org/10.1046/j.1440-0952.2001.485888.x.

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Fegan, N. E., D. T. Long, W. B. Lyons, M. E. Hines, and P. G. Macumber. "Metal partitioning in acid hypersaline sediments: Lake Tyrrell, Victoria, Australia." Chemical Geology 96, no. 1-2 (March 1992): 167–81. http://dx.doi.org/10.1016/0009-2541(92)90127-q.

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Webster-Brown, J. G., and K. S. Webster. "Trace metals in cyanobacterial mats, phytoplankton and sediments of the Lake Vanda region, Antarctica." Antarctic Science 19, no. 3 (June 29, 2007): 311–19. http://dx.doi.org/10.1017/s0954102007000417.

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AbstractThe degree and nature of association between trace metals (Cu, Pb, Zn, Ni, Ag, & Cd) and cyanobacterial mats, phytoplankton and sediments has been assessed in the Lake Vanda region of the Wright Valley, Victoria Land. Trace metal:Fe ratios and SEM imaging confirmed that apparent trace metal enrichment in cyanobacterial mats, relative to the sediment beneath, was due to incorporation of fine (sub-micron) sediment particles in the muciligenous matrix of the mat. In suspended particulate material (SPM) filtered from the oxic water of Lake Vanda and the Onyx River, the degree of trace metal binding to the SPM did not appear to correlate with phytoplankton content. Instead a positive correlation was observed between Fe and trace metal content. The SPM at the top of the lake water column, where only the finest sediment remains suspended, had the highest trace metal concentrations. It is concluded that the trace metal content of cyanobacterial mats and phytoplankton samples is primarily due to incorporation of fine sediment particles of high surface area which therefore enhance trace metal adsorption capacity. This reinforces the existing hypothesis that trace metal solubility in this environment is primarily controlled by abiotic processes.

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Anderson, John G., and James N. Brune. "The Victoria Accelerogram for the 1980 Mexicali Valley Earthquake." Earthquake Spectra 7, no. 1 (February 1991): 29–43. http://dx.doi.org/10.1193/1.1585611.

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Most of the remarkable digital strong motion accelerogram from the June 9, 1980 Mexicali Valley earthquake (Mw = 6.4) has been recovered by careful analysis. Peak horizontal accelerations (.98g, .87g) and duration were similar to the values for the recent Superstition Hills earthquake. The vertical accelerogram clipped the 1g instrument several times. The records provide an important example of near fault accelerations from a second earthquake in the deep sediments of the Imperial Mexicali Valley (the other being the records from the 1979 Imperial Valley earthquake). The 1980 accelerograms are important because they were not affected by foundation filtering, as were the records for the Imperial Valley 1940 earthquake, and because they illustrate the damaging near-source, intermediate frequency velocity pulse associated with passage of the rupture front.

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Viezzoli, Andrea, and James Cull. "Electrical Methods for Detection and Discrimination of Saline Groundwater in Clay-Rich Sediments in Northern Victoria." Exploration Geophysics 36, no. 3 (September 2005): 294–300. http://dx.doi.org/10.1071/eg05294.

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Cook, Y. A. "Precambrian rift-related magmatism and sedimentation, south Victoria Land, Antarctica." Antarctic Science 19, no. 4 (August 16, 2007): 471–84. http://dx.doi.org/10.1017/s0954102007000612.

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AbstractPrecambrian continental extension is described in detail for the first time in the Victoria Land segment of the Transantarctic Mountains and is comparable with plume related intercontinental rifting of the Afar area, Africa. The Baronick Formation comprises igneous-derived conglomerate, marble and volcanic to sub-volcanic igneous layers. Volcanic and carbonate horizons were eroded in a fluvial or marine environment and provided debris for mass flow and slump deposits which formed in a marginal marine basin in the Precambrian. Clasts in these deposits include basalt, trachyte and comendite, and along with the interbedded volcanic layers of basalt, trachyte and quartz syenite, indicate proximity and contemporaneity of volcanic activity. Igneous layers and source rocks for clasts of the Baronick Formation have an enriched MORB chemistry and underwent albitization of calcic feldspar before erosion and conglomerate deposition. The Highway Suite forms a kilometre-scale body of gabbro and dolerite plugs and is interpreted as a slice of transitional continental oceanic crust. The chemistry of all igneous rocks suggests a continental rift environment and the associated sediments are consistent with such a setting. The Baronick Formation was locally intruded by sills of the Highway Suite; however, the main body of the Highway Suite was juxtaposed against the Baronick Formation during greenschist facies shearing before c. 551 Ma.

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Lemenkova, Polina. "Data-driven insights into correlation among geophysical setting, topography and seafloor sediments in the Ross Sea, Antarctic." Caderno de Geografia 31, no. 64 (December 9, 2020): 1. http://dx.doi.org/10.5752/p.2318-2962.2021v31n64p1.

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Detailed mapping based on the high-resolution grids, such as GEBCO, ETOPO1, GlobSed, EGM-2008 is crucial for various domains of Earth sciences: geophysics, glaciology, Quaternary, sedimentology, geology, environmental science, geomorphology, etc. The study presented a GMT-based scripting techniques of the cartographic data processing aimed at the comparative analysis of the bathymetry, sediment thickness, geologic objects and geophysical settings in the study area based on various datasets. The study area is located in the Ross Sea, Antarctic. The highest values of the sediment thickness over 7,500 m are dominating in the southwest segment of the Ross Sea closer to the Victoria Land, followed by the region over the Ross Ice Shelf with values between 5,500 to 7,000 m (170°-175°W). The increased sediment thickness (2,500 to 3,000 m) was also mapped seen in the region NE off the Sulzberger Bay (70-75°S to 140-155°W), caused by the closeness of the Marie Bird Land ice coasts. A remarkable correlation between the gravity and the topography of the sea-land border in the Marie Bird Land area is well reflected in the coastal line and a set of the higher values in the free-air gravity. On the contrary, negative values (–60 to -80 mGal) are notable along the submarine toughs stretching parallel in the western part of the basin: e.g. the trough stretching in NW-SE direction in the 170°W-175°E, 65°S-68°S, between the 167°W-175°W, 70°S-72°S. Such correlations are clearly visible on the map, indicating geological lineaments and bathymetric depressions correlating with gravity grids. The paper contributes to the regional studies of the Ross Sea, the Antarctic and Polar region, and development of the cartographic technical methodologies by presenting an application of the GMT for thematic mapping.

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Webb, J. A., D. Fabel, B. L. Finlayson, M. Ellaway, Li Shu, and H. P. Spiertz. "Denudation chronology from cave and river terrace levels: the case of the Buchan Karst, southeastern Australia." Geological Magazine 129, no. 3 (May 1992): 307–17. http://dx.doi.org/10.1017/s0016756800019245.

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AbstractDetailed mapping of surface and underground karst features at Buchan, in eastern Victoria, has shown that the three river terraces along the Buchan River can be correlated with three levels of epiphreatic development in the nearby caves. Each level represents a stillstand in the denudational history of the area. Uranium series dating of speleothems and palaeomagnetic studies of cave sediments indicate that all three stilistands are more than 730 ka old. The periods of incision separating the stillstands were probably the result of active tectonic uplift. This contrasts with some northern parts of the Southeastern Highlands, which have been stable since the Eocene. The overall amount of incision and uplift at Buchan is small, indicating that the majority of scarp retreat in this section of the highlands must have occurred earlier. The denudation history of the Buchan area over the last 730 ka has seen only 2–3 m of incision, despite the major climatic and sea-level changes that have occurred in that time. Whereas most karst landscapes in the Northern Hemisphere have been extensively modified during the late Pleistocene, the Buchan karst was little affected, and its geomorphology has an older origin.

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Ricci, C. A., F. Talarico, R. Palmeri, G. Di Vincenzo, and P. C. Pertusati. "Eclogite at the Antarctic palaeo-Pacific active margin of Gondwana (Lanterman Range, northern Victoria Land, Antarctica)." Antarctic Science 8, no. 3 (September 1996): 277–80. http://dx.doi.org/10.1017/s0954102096000399.

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Well-preserved eclogites were found for the first time in Antarctica, at the Lanterman Range, northern Victoria Land. They are part of a mafic–ultramafic belt that lies between the Wilson Terrane, representing part of the palaeo-Pacific margin of Gondwana, and the Bowers Terrane, a Cambro-Ordovician volcanic are and related sediments, accreted to the margin during the Ross Orogeny. The eclogites formed at temperatures in the range 750–850°C and pressures above 15 kbar and subsequently experienced a decompressional path to low pressure amphibolite facies conditions. The formation and exhumation of eclogites and the attainment of the metamorphic peak in adjacent rock units is consistent with a plate convergent setting model at the palaeo-Pacific margin of Gondwana.

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11

Webster-Brown, J., M. Gall, J. Gibson, S. Wood, and I. Hawes. "The biogeochemistry of meltwater habitats in the Darwin Glacier region (80°S), Victoria Land, Antarctica." Antarctic Science 22, no. 6 (December 2010): 646–61. http://dx.doi.org/10.1017/s0954102010000787.

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AbstractMeltwater habitats in the Darwin Glacier region, Victoria Land (80°S), were sampled in December 2007 and January 2009 to characterize their microbial and metazoan ecology, nutrient status and geochemistry. Targeted areas included terrestrial ponds of the Grant Valley, Lake Wellman, Tentacle Ridge and Diamond Hill, and supraglacial ponds and cryoconite holes of the lower Darwin Glacier. Geochemistry ranged from Na-Cl dominated terrestrial ponds to Na-HCO3dominated, dilute supraglacial ponds and cryoconites. All showed the nitrate enrichment typical of inland ponds of Victoria Land (up to 13 g.l-1NO3-N), with some precipitating nitratine (NaNO3) salt. Elevated pH indicated ongoing photosynthetic processes. Benthic microbial mats were thin and poorly developed, dominated by oscillatoriacean cyanobacteria. Nitrogen-fixing genera were generally absent and diatoms were rare. A large (20 μm long)Cyanothecespecies was the most abundant cyanobacterium in the water and in sediments of the cryoconites. DNA finger-printing identified distinct differences in cyanobacterial and bacterial community structure between the cryoconites, terrestrial ponds and ponds on glacial margins. Eleven metazoan species were identified, with rotifers being the most abundant. Pond substrate (terrestrial rock, ice-cored moraine or supraglacial ice) proved to be a more significant influence on biogeochemistry than other aspects of geography or climatic conditions.

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McNiven, Ian J., Joe Crouch, Jim M. Bowler, John E. Sherwood, Nic Dolby, Julian E. Dunn, and John Stanisic. "The Moyjil site, south-west Victoria, Australia: excavation of a Last Interglacial charcoal and and burnt stone feature — is it a hearth?" Proceedings of the Royal Society of Victoria 130, no. 2 (2018): 94. http://dx.doi.org/10.1071/rs18008.

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Claims for a human presence in Australia beyond 60,000 years ago must have a strong evidence base associated with rigorous methodology and intense scrutiny. In this light we present excavation results for Charcoal and Burnt Stone Feature #1 (CBS1) located within coastal dune sediments at Moyjil (Point Ritchie), Warrnambool, that independent geomorphic and OSL dating indicates is of Last Interglacial age (~120,000 years ago). While on plausibility grounds the cultural status of a feature of such great antiquity in Australia is unlikely, a cultural origin for CBS1 is less easily dismissed if assessed with an age-independent methodology. A broad range of macroscale discrimination criteria has been used to assess whether CBS1 is either a cultural hearth or a natural feature such as a burnt tree stump. On balance, evidence marginally supports a cultural origin over a natural origin. However, the absence of associated stone artefacts and faunal remains and the presence of burnt root wood precludes definitive statements on the cultural status of the feature. Our case study is methodologically instructivein terms of the potential complexities and issues of equifinality involved in the archaeological identification of ancient hearths.

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Gardner, Christopher B., and W. Berry Lyons. "Modelled composition of cryogenically produced subglacial brines, Antarctica." Antarctic Science 31, no. 3 (March 29, 2019): 165–66. http://dx.doi.org/10.1017/s095410201900004x.

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Polar subglacial hydrologic systems have garnered much interest since the recognition of Lake Vostok in 1996. In Antarctica, these environments are hydrologically diverse, including isolated lakes of different sizes, river–lake flow-through systems, “swamps” and groundwater (Siegert 2016). The refreezing of subglacial meltwater is also an important process beneath a large portion of the East Antarctic Ice Sheet (Bell et al. 2011). As subglacial water refreezes it exsolves salts, potentially leaving behind saline and hypersaline brines. Brines thought to derive from this cryoconcentration process have been observed in the northern polar permafrost regions and in the McMurdo Dry Valleys (MDVs) region of Antarctica. Additionally, sediments in the Victoria Land Basin have diagenetic signatures produced by brine movement dating from 3–11 m.y.a, suggesting hypersaline brines have existed in the McMurdo region since at least this time (Staudigel et al. 2018).

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Povero, Paolo, Michela Castellano, Nicoletta Ruggieri, Luis S. Monticelli, Vincenzo Saggiomo, Mariachiara Chiantore, Marta Guidetti, and Riccardo Cattaneo-Vietti. "Water column features and their relationship with sediments and benthic communities along the Victoria Land coast, Ross Sea, summer 2004." Antarctic Science 18, no. 4 (November 14, 2006): 603–13. http://dx.doi.org/10.1017/s0954102006000642.

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The northern Victoria Land coastal marine environment was investigated during the late summer 2004, within the framework of the Latitudinal Gradient Project (LGP), to describe the physical, chemical and biological patterns of the water column and their relationship with the pelagic and benthic compartments, and to determine to what extent they change with latitude. A latitudinal gradient from Cape Adare to the Terra Nova Bay–Cape Russell area was determined on the basis of abiotic and trophic factors. Cape Adare had lower values of organic matter (particulate organic carbon < 150 μg l−1) available for the benthic communities, but this organic matter had good trophic quality. In Terra Nova Bay the particulate organic matter was quantitatively higher (organic carbon > 400 μg l−1), presumably reaching the bottom via faecal pellets, but was more detrital, although its nutritive value was still high (carbon protein content nearly 40%), as confirmed by the great quantity of phytopigments in the sediments (> 4.0 μg g−1). The benthic communities changed with latitude as well, partially reflecting the environmental and trophic gradient, but also showing a large within-area variability (except for the Cape Adare area), due to a complex array of variables that did not change with latitude.

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Yau, C. C., V. N. L. Wong, and D. M. Kennedy. "Soil chemistry and acidification risk of acid sulfate soils on a temperate estuarine floodplain in southern Australia." Soil Research 54, no. 7 (2016): 787. http://dx.doi.org/10.1071/sr15174.

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The distribution and geochemical characterisation of coastal acid sulfate soils (CASS) in Victoria in southern Australia is relatively poorly understood. This study investigated and characterised CASS and sulfidic material at four sites (wetland (WE), swamp scrub (SS), woodland (WO) and coastal tussock saltmarsh (CTS)) on the estuarine floodplain of the Anglesea River in southern Australia. Shell material and seawater buffered acidity generated and provided acid-neutralising capacity (up to 10.65% CaCO3-equivalent) at the sites located on the lower estuarine floodplain (WO and CTS). The SS site, located on the upper estuarine floodplain, can potentially acidify soil and water due to high positive net acidity (>200molH+t–1) and a limited acid-neutralising capacity. High titratable actual acidity in the SS and WO profiles (>270molH+t–1) were the result of high organic matter in peat-like layers that can potentially contribute organic acids in addition to acidity formed from oxidation of sulfidic sediments. The results of the present study suggest that the environments and chemistry of acid sulfate soils in southern Australia are distinct from those located in eastern Australia; this may be related to differences in estuarine processes that affect formation of acid sulfate soils, as well as the geomorphology and geology of the catchment.

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McNamara, K. J., and C. Ah Yee. "A new genus of brissid echinoid from the Miocene of Australia." Geological Magazine 126, no. 2 (March 1989): 177–86. http://dx.doi.org/10.1017/s0016756800006312.

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AbstractThe brissid echinoid Amoraster (gen. nov.) is described from Miocene strata in southern Australia on the basis of two species: A. paucituberculata sp. nov., which ranges from the Batesfordian (latest Early Miocene) Bochara Limestone to the Bairnsdalian–Mitchellian (Middle–Late Miocene) Port Campbell Limestone in Victoria; and A. tuberculata sp. nov. from the Longfordian (Early Miocene) Mannum Formation in South Australia. Morphological changes which occurred with the evolution of A. paucituberculata from A. tuberculata are interpreted as being adaptations to the occupation of a finer grained sediment by the descendant species.

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Beuning, Kristina R. M., Kerry Kelts, Emi Ito, and Thomas C. Johnson. "Paleohydrology of Lake Victoria, East Africa, inferred from 18O/16O ratios in sediment cellulose." Geology 25, no. 12 (1997): 1083. http://dx.doi.org/10.1130/0091-7613(1997)025<1083:polvea>2.3.co;2.

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Sherwood, John E., Jim M. Bowler, Stephen P. Carey, John Hellstrom, Ian J. McNiven, Colin V. Murray-Wallace, John R. Prescott, et al. "The Moyjil site, south-west Victoria, Australia: chronology." Proceedings of the Royal Society of Victoria 130, no. 2 (2018): 32. http://dx.doi.org/10.1071/rs18005.

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An unusual shell deposit at Moyjil (Point Ritchie), Warrnambool, in western Victoria, has previously been dated at 67±10 ka and has features suggesting a human origin. If human, the site would be one of Australia’s oldest, justifying a redetermination of age using amino acid racemisation (AAR) dating of Lunella undulata (syn. Turbo undulatus) opercula (the dominant shellfish present) and optically stimulated luminescence (OSL) of the host calcarenite. AAR dating of the shell bed and four Last Interglacial (LIG) beach deposits at Moyjil and Goose Lagoon, 30 km to the west, confirmed a LIG age. OSL analysis of the host sand revealed a complex mixing history, with a significant fraction (47%) of grains giving an early LIG age (120–125 ka) using a three-component mixing model. Shell deposition following the LIG sea-level maximum at 120–125 ka is consistent with stratigraphic evidence. A sand layer immediately below the shell deposit gave an age of ~240 ka (i.e. MIS 7) and appears to have been a source of older sand incorporated into the shell deposit. Younger ages (~60–80 ka) are due to bioturbation before calcrete finally sealed the deposit. Uranium/thorium methods were not applicable to L. undulata opercula or an otolith of the fish Argyrosomus hololepidotus because they failed to act as closed systems. A U–Th age of 103 ka for a calcrete sheet within the 240 ka sand indicates a later period of carbonate deposition. Calcium carbonate dripstone from a LIG wave-cut notch gave a U–Th age of 11–14 ka suggesting sediment cover created a cave-like environment at the notch at this time. The three dating techniques have collectively built a chronology spanning the periods before and after deposition of the shell bed, which occurred just after the LIG sea-level maximum (120–125 ka).

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Beuning, Kristina R. M., Kerry Kelts, Jim Russell, and Brent B. Wolfe. "Reassessment of Lake Victoria–Upper Nile River paleohydrology from oxygen isotope records of lake-sediment cellulose." Geology 30, no. 6 (2002): 559. http://dx.doi.org/10.1130/0091-7613(2002)030<0559:rolvun>2.0.co;2.

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20

Wagner, Bernd, Sabrina Ortlepp, Peter T. Doran, Fabien Kenig, Martin Melles, and Andy Burkemper. "The Holocene environmental history of Lake Hoare, Taylor Valley, Antarctica, reconstructed from sediment cores." Antarctic Science 23, no. 3 (February 16, 2011): 307–19. http://dx.doi.org/10.1017/s0954102011000125.

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AbstractUp to 2.3 m long sediment sequences were recovered from the deepest part of Lake Hoare in Taylor Valley, southern Victoria Land, Antarctica. Sedimentological, biogeochemical, and mineralogical analyses revealed a high spatial variability of these parameters in Lake Hoare. Five distinct lithological units were recognized. Radiocarbon dating of bulk organic carbon samples from the sediment sequences yielded apparently too old ages and significant age reversals, which prevented the establishment of reliable age-depth models. However, cross correlation of the sedimentary characteristics with those of sediment records from neighbouring Lake Fryxell indicates that the lowermost two units of the Lake Hoare sediment sequences were probably deposited during the final phase of proglacial Lake Washburn, which occupied Taylor Valley during the late Pleistocene and early Holocene. High amounts of angular gravel and the absence of fine-grained material imply a complete desiccation with subaerial conditions in the Lake Hoare basin in the middle of the Holocene. The late Holocene (< c. 3300 calendar yr bp) is characterized by the establishment of environmental conditions similar to those existing today. A late Holocene desiccation event, such as proposed in former studies, is not indicated in the sediment sequences recovered.

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Cummings, V. J., S. F. Thrush, M. Chiantore, J. E. Hewitt, and R. Cattaneo-Vietti. "Macrobenthic communities of the north-western Ross Sea shelf: links to depth, sediment characteristics and latitude." Antarctic Science 22, no. 6 (December 2010): 793–804. http://dx.doi.org/10.1017/s0954102010000489.

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AbstractIn early 2004 the Victoria Land Transect project sampled coastal north-western Ross Sea shelf benthos at Cape Adare, Cape Hallett, Cape Russell and Coulman Island from 100–500 m deep. We describe the benthic macrofaunal assemblages at these locations and, to assess the use of seafloor sediment characteristics and/or depth measures in bioregionalizations, determine the extent to which assemblage compositions are related to measured differences in these factors. Percentages of fine sand and silt, the ratio of sediment chlorophyllato phaeophytin, and depth were identified as important explanatory variables, but in combination they explained only 17.3% of between-location differences in assemblages. Consequently, these variables are clearly not strong determinants of macrofaunal assemblage structure. Latitudeper sewas not a useful measure of community variability and change. A significant correlation between both number of individuals and number of taxa and sediment phaeophytin concentration across locations suggests that the distribution of the benthos reflects their response to seafloor productivity. A number of factors not measured in this study have probably influenced the structure and function of assemblages and habitats. We discuss the implications of the results to marine classifications, and stress the need to incorporate biogenic habitat complexity into protection strategies.

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Finocchiaro, Furio, Carlo Baroni, Ester Colizza, and Roberta Ivaldi. "Pre-LGM open-water conditions south of the Drygalski Ice Tongue, Ross Sea, Antarctica." Antarctic Science 19, no. 3 (July 13, 2007): 373–77. http://dx.doi.org/10.1017/s0954102007000430.

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AbstractA marine sediment core collected from the Nordenskjold Basin, to the south of the Drygalski Ice Tongue, provides new sedimentological and chronological data for reconstructing the Pleistocene glacial history and palaeoenvironmental evolution of Victoria Land. The core consists of an over consolidated biogenic mud covered with glacial diamicton; Holocene diatomaceous mud lies on top of the sequence. Radiocarbon dates of the acid insoluble organic matter indicate a pre-Last Glacial Maximum age (>24kyr) for the biogenic mud at the base of the sequence. From this we can presume that at least this portion of the western Ross Sea was deglaciated during Marine Isotope Stage 3 and enjoyed open marine conditions. Our results are consistent with recent findings of pre-Holocene raised beaches at Cape Ross and in the Terra Nova Bay area.

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Winton, V. H. L., G. B. Dunbar, C. B. Atkins, N. A. N. Bertler, B. Delmonte, P. S. Andersson, A. Bowie, and R. Edwards. "The origin of lithogenic sediment in the south-western Ross Sea and implications for iron fertilization." Antarctic Science 28, no. 4 (February 26, 2016): 250–60. http://dx.doi.org/10.1017/s095410201600002x.

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AbstractSummer iron (Fe) fertilization in the Ross Sea has previously been observed in association with diatom productivity, lithogenic particles and excess Fe in the water column. This productivity event occurred during an early breakout of sea ice via katabatic winds, suggesting that aeolian dust could be an important source of lithogenic Fe required for diatom growth in the Ross Sea. Here we investigate the provenance of size-selected dust deposited on sea ice in McMurdo Sound, south-western (SW) Ross Sea. The isotopic signature of McMurdo Sound dust (0.70533<87Sr/86Sr<0.70915 and -1.1<εNd(0)<3.45) confirms that dust is locally sourced from the McMurdo Sound debris bands and comprises a two-component mixture of McMurdo Volcanic Group and southern Victoria Land lithologies. In addition, the provenance of lithogenic sediment trapped in the water column was investigated, and the isotopic signature (εNd(0)=3.9, 87Sr/86Sr=0.70434) is differentiated from long-range transported dust originating from South America and Australia. Elevated lithogenic accumulation rates in deeper sediment traps in the Ross Sea suggest that sinking particles in the water column cannot simply result from dust input at the surface. This discrepancy can be best explained by significant upwelling and remobilization of lithogenic Fe from the sea floor.

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Kennedy, David M., Thomas S. N. Oliver, Toru Tamura, Colin V. Murray-Wallace, Bruce G. Thom, Neville J. Rosengren, Daniel Ierodiaconou, et al. "Holocene evolution of the Ninety Mile Beach sand barrier, Victoria, Australia: The role of sea level, sediment supply and climate." Marine Geology 430 (December 2020): 106366. http://dx.doi.org/10.1016/j.margeo.2020.106366.

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Adams, C. J., J. D. Bradshaw, and T. R. Ireland. "Provenance connections between late Neoproterozoic and early Palaeozoic sedimentary basins of the Ross Sea region, Antarctica, south-east Australia and southern Zealandia." Antarctic Science 26, no. 2 (July 18, 2013): 173–82. http://dx.doi.org/10.1017/s0954102013000461.

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AbstractThick successions of turbidites are widespread in the Ross–Delamerian and Lachlan orogens and are now dispersed through Australia, Antarctica and New Zealand. U-Pb detrital zircon age patterns for latest Precambrian, Cambrian and Ordovician metagreywackes show a closely related provenance. The latest Neoproterozoic–early Palaeozoic sedimentary rocks have major components, at c. 525, 550, and 595 Ma, i.e. about 40–80 million years older than deposition. Zircons in these components increase from the Neoproterozoic to Ordovician. Late Mesoproterozoic age components, 1030 and 1070 Ma, probably originate from igneous/metamorphic rocks in the Gondwanaland hinterland whose exact locations are unknown. Although small, the youngest zircon age components are coincident with estimated depositional ages suggesting that they reflect contemporaneous and minor, volcanic sources. Overall, the detrital zircon provenance patterns reflect the development of plutonic/metamorphic complexes of the Ross–Delamerian Orogen in the Transantarctic Mountains and southern Australia that, upon exhumation, supplied sediment to regional scale basin(s) at the Gondwana margin. Tasmanian detrital zircon age patterns differ from those seen in intra-Ross Orogen sandstones of northern Victoria Land and from the oldest metasediments in the Transantarctic Mountains. A comparison with rocks from the latter supports an allochthonous western Tasmania model and amalgamation with Australia in late Cambrian time.

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Ribbe, Nils, Kenneth Arinaitwe, Tallent Dadi, Kurt Friese, and Wolf von Tümpling. "Trace-element behaviour in sediments of Ugandan part of Lake Victoria: results from sequential extraction and chemometrical evaluation." Environmental Earth Sciences 80, no. 8 (April 2021). http://dx.doi.org/10.1007/s12665-021-09554-1.

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AbstractLake Victoria is the second largest freshwater lake and the largest tropical lake in the world. The transboundary lake has the fastest growing population in its catchment, which can impact the water and sediment quality. To determine the extent of anthropogenic effects on sediment quality in the Ugandan part of Lake Victoria, the contents and binding behaviour of trace elements were analysed, as well as organic matter and phosphorus in different sediment layers of both deep and coastal sediments near the coastal cities of Entebbe, Kampala and Jinja. The data were assessed using the German LAWA criteria for trace-element pollution, the Geo-Index, Cluster- and Factor analyses. Mostly, no critical trace-element contamination in the sediments of the investigated area was observed. However, changes in element distributions caused by anthropogenic influences from around the lake were detected, like higher contents of Cu, Ti and V in near shore sediments with urban surrounding. Near Jinja, industrial wastewaters caused particularly elevated contents of Cu in the sediments (70–121 mg/kg, 3.5–6 times the geogenic background), exceeding the LAWA criteria and potentially harming the aquatic habitat. In addition, temporally growing organic matter contents in the lake sediments near the estuary of River Nzoia (from 4.2 to 17.6% in around 60 years) due to increased soil erosion in the river’s catchment area and blooms of the water hyacinth became visible. This study demonstrates that the whole catchment area is responsible to ensure a healthy aquatic ecosystem in Lake Victoria.

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Zurli, Luca, Gianluca Cornamusini, Jusun Woo, Giovanni Pio Liberato, Seunghee Han, Yoonsup Kim, and Franco Maria Talarico. "Detrital zircons from Late Paleozoic Ice Age sequences in Victoria Land (Antarctica): New constraints on the glaciation of southern Gondwana." GSA Bulletin, April 27, 2021. http://dx.doi.org/10.1130/b35905.1.

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The Lower Permian tillites of the Beacon Supergroup, cropping out in Victoria Land (Antarctica), record climatic history during one of the Earth’s coldest periods: the Late Paleozoic Ice Age. Reconstruction of ice-extent and paleo-flow directions, as well as geochronological and petrographic data, are poorly constrained in this sector of Gondwana. Here, we provide the first detrital zircon U-Pb age analyses of both the Metschel Tillite in southern Victoria Land and some tillites correlatable with the Lanterman Formation in northern Victoria Land to identify the source regions of these glaciogenic deposits. Six-hundred detrital zircon grains from four diamictite samples were analyzed using laser ablation−inductively coupled plasma−mass spectrometry. Geochronological and petrographic compositional data of the Metschel Tillite indicate a widespread reworking of older Devonian Beacon Supergroup sedimentary strata, with minor contribution from Cambro-Ordovician granitoids and meta-sedimentary units as well as Neoproterozoic metamorphic rocks. Euhedral to subhedral Carboniferous−Devonian zircon grains match coeval magmatic units of northern Victoria Land and Marie Byrd Land. This implies, in accordance with published paleo-ice directions, a provenance from the east-southeast sectors. In contrast, the two samples from northern Victoria Land tillite reflect the local basement provenance; their geochronological age and petrographic composition indicates a restricted catchment area with multiple ice centers. This shows that numerous ice centers were present in southern Gondwana during the Late Paleozoic Ice Age. While northern Victoria Land hosted discrete glaciers closely linked with the northern Victoria Land-Tasmania ice cap, the west-northwestward flowing southern Victoria Land ice cap contributed most of the sediments comprising the Metschel Tillite.

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Journal articles on the topic 'Sediments (Geology) Victoria'

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