Journal articles on the topic 'Non-marine sediments'
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Talbot, Helen M., Diane F. Watson, Emma J. Pearson, and Paul Farrimond. "Diverse biohopanoid compositions of non-marine sediments." Organic Geochemistry 34, no. 10 (October 2003): 1353–71. http://dx.doi.org/10.1016/s0146-6380(03)00159-1.
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Lejzerowicz, Franck, Philippe Esling, Wojciech Majewski, Witold Szczuciński, Johan Decelle, Cyril Obadia, Pedro Martinez Arbizu, and Jan Pawlowski. "Ancient DNA complements microfossil record in deep-sea subsurface sediments." Biology Letters 9, no. 4 (August 23, 2013): 20130283. http://dx.doi.org/10.1098/rsbl.2013.0283.
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Deep-sea subsurface sediments are the most important archives of marine biodiversity. Until now, these archives were studied mainly using the microfossil record, disregarding large amounts of DNA accumulated on the deep-sea floor. Accessing ancient DNA (aDNA) molecules preserved down-core would offer unique insights into the history of marine biodiversity, including both fossilized and non-fossilized taxa. Here, we recover aDNA of eukaryotic origin across four cores collected at abyssal depths in the South Atlantic, in up to 32.5 thousand-year-old sediment layers. Our study focuses on Foraminifera and Radiolaria, two major groups of marine microfossils also comprising diverse non-fossilized taxa. We describe their assemblages in down-core sediment layers applying both micropalaeontological and environmental DNA sequencing approaches. Short fragments of the foraminiferal and radiolarian small subunit rRNA gene recovered from sedimentary DNA extracts provide evidence that eukaryotic aDNA is preserved in deep-sea sediments encompassing the last glacial maximum. Most aDNA were assigned to non-fossilized taxa that also dominate in molecular studies of modern environments. Our study reveals the potential of aDNA to better document the evolution of past marine ecosystems and opens new horizons for the development of deep-sea palaeogenomics.
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Mutmainah, Herdiana, and Rini Kusumawardani. "Sediment Characteristic of Pagai Strait, Mentawai." Jurnal Teknik Sipil dan Perencanaan 21, no. 1 (July 15, 2019): 28–38. http://dx.doi.org/10.15294/jtsp.v21i1.19914.
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Abstract. The marine sediment is important indicator of the seafloor. The characteristics of marine sediments can be seen from grain size, type and Total Dissolved Solid (TDS). Sediments derived from organic and non-organic particles are carried by the sea currents, waves, streams and tidal process in the coastal areas. At very high levels, sediments can cause pollution or vulnerability such as decreasing of dissolved oxygen, coral bleaching, and increased the eurotrification processes. Pagai Strait is located between North Pagai Island and South Pagai. This strait has enormous potential and it is used by the surrounding community for various activities such as port and sea transportation, fishery, marine aquaculture and tourism. This study aims to determine the characteristics of sediment in Pagai Strait. The field survey was conducted in September 2016 for waves, currents, water quality and sediment samples with purposive sampling method. The results showed that the average of sediments in Pagai Strait is D35 sized 0.155 mm; D50 sized 0.273 mm; and D90 sized 1.574 mm with specific gravity 2.665 gr/cm3 and dominated by sand 66.88%. TDS between 51.6 to 55.0 mg/L, appropriate for port and mangrove. Scale of sediment, A = 0.119 and sediment velocity is 0.002 m/s. Sediment transport approximately is 0.389 m3/day.
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Neff, Jerry M., Paul D. Boehm, Roy Kropp, William A. Stubblefield, and David S. Page. "Monitoring Recovery of Prince William Sound, Alaska, Following the Exxon Valdez Oil Spill: Bioavailability of PAH in Offshore Sediments." International Oil Spill Conference Proceedings 2003, no. 1 (April 1, 2003): 299–305. http://dx.doi.org/10.7901/2169-3358-2003-1-299.
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ABSTRACT We determined the bioavailability to sediment-dwelling marine worms of polycyclic aromatic hydrocarbons (PAHs) associated with offshore sediments from 3 spill path and 3 non-spill path areas of Prince William Sound (PWS), Alaska, 12 years after the Exxon Valdez oil spill. The PAHs in sediments from 4 sites sampled in 2001 were primarily from a regional natural petrogenic background derived from organic-rich shales and natural oil seeps associated with sources southeast of PWS. Pyrogenic (combustion) PAHs, primarily from former human and industrial activities, were more abundant than petrogenic PAHs in nearshore sediments from 2 bays associated with past and current human activities. We performed sediment bioaccumulation tests with the six sediments and polychaete worms according to standard EPA protocols. All the PAHs had a very low bioavailability, as indicated by low values for biota/sediment accumulation factors (BSAFs) in the worms. Mean BSAFs for total PAHs (sum of 41 analyte groups) ranged from 0.002 to 0.009. The worms exposed to spill path and non-spill path sediments bioaccumulated small amounts of 4- and 5-ring PAHs, particularly fluoranthene and pyrene; these higher molecular weight PAHs are responsible for induction of mixed function oxygenase (MFO) activity in marine fish, birds, and mammals. These results may help to explain in part why fish from throughout PWS exhibit induced MFO activity. Elevated levels of MFO activity cannot be used as evidence of recent exposure by marine fish, birds, and mammals in the sound to Exxon Valdez oil.
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Cook, Nancy H., and Peter G. Wells. "Toxicity of Halifax Harbour Sediments: an Evaluation of the Microtox® Solid-Phase Test." Water Quality Research Journal 31, no. 4 (November 1, 1996): 673–708. http://dx.doi.org/10.2166/wqrj.1996.037.
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Abstract Subtidal sediments were collected in Halifax Harbour, Nova Scotia, in July and August, 1992, to study sediment toxicity and hazards near the proposed location of a sewage treatment plant and outfall. A set of 110 samples from eight stations was evaluated. Interstitial water from surface (0-2 cm) and subsurface (2-4 cm) sediments was analyzed by the Microtox® 100% toxicity test protocol. The sediment particles were analyzed using the Microtox® solid-phase test. Interstitial water from surface and subsurface sediments from all stations was usually non-toxic, compared to a phenol standard. The mean 5 min-EC50 of surface sediments (n=57) was 5,433mg/L; the mean 5 min-EC50 of subsurface sediments (n=50) was 804 mg/L. Toxicity thresholds for the harbour sediments were compared with National Research Council marine analytical sediment reference materials and a selection of natural sediments, and ranked. An experiment with the marine reference sediments (certified for PAHs and trace metals) and their mixtures showed the ability of the solid-phase test to discriminate among different levels of contaminated sediments. Intra- and inter-sample variability in toxicity at different locations in relation to time, sediment depth, sediment properties, and types and concentrations of contaminants was evaluated by multivariate and PCA tech-niques. This laboratory-field study provided insights into the sensitivity, repro-ducibility, significance and discriminatory ability of the Microtox® solid-phase bioassay and its value in the study of complex natural sediment mixtures.
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Pramod Kumar, G. L. Das, and Atul Garg. "Heavy metal accumulation in marine sediments - An assessment in ONGC’s platforms in Mumbai High Region, Arabian Sea." World Journal of Advanced Engineering Technology and Sciences 02, no. 01 (March 30, 2021): 060–68. http://dx.doi.org/10.30574/wjaets.2021.2.1.0026.
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Heavy metal pollution, in the aquatic ecosystem, especially sediments, has become an area of concern garnering increasing attention since the past few decades. Some metals like manganese (Mn), copper (Cu), iron (Fe) and zinc (Zn) are biologically important for marine life, others like lead (Pb), cadmium (Cd), and Arsenic (As) are non-essential and become toxic at higher concentrations. These metals introduced into the marine ecosystem mainly due to anthropogenic activities. These heavy metals when discharged into the marine ecosystem may be absorbed in suspended solids, remain in seawater, etc., but ultimately end up in the sediments which act as a “sink” and later the “source”, due to their restricted mobility. Hence, monitoring the heavy metal concentrations in these marine sediments over a period of time is of great help in checking the pollution level and identifying the trend, which in turn will be instrumental in formulating sustainable practices. The paper mainly focuses on the study of the concentration of non-essential heavy metals in sea sediment around the operational areas of ONGC in western offshore area. The distribution of heavy metals in the sediments of ONGC’s exploratory blocks in Mumbai High Region, Arabian Sea was investigated. Surface sediment samples collected from 5 platforms (R-12A, BLQ, NBP, ICP and NQ) of Mumbai High Region, Arabian Sea and digested samples were analyzed by ICP-MS for 75As, 111Cd and 208Pb. Comparison of results in studied 5 platforms with various sediment quality guidelines is discussed to assess the present contamination. It reveals that sediments in study area are not contaminated with respect to perceived heavy metals. Generated data will assist in future for proactive measures and minimize the impact of anthropogenic sources.
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Kelly, S. B. "Milankovitch cyclicity recorded from Devonian non-marine sediments." Terra Nova 4, no. 5 (September 1992): 578–84. http://dx.doi.org/10.1111/j.1365-3121.1992.tb00599.x.
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Strother, Stephanie L., Ulrich Salzmann, Francesca Sangiorgi, Peter K. Bijl, Jörg Pross, Carlota Escutia, Ariadna Salabarnada, Matthew J. Pound, Jochen Voss, and John Woodward. "A new quantitative approach to identify reworking in Eocene to Miocene pollen records from offshore Antarctica using red fluorescence and digital imaging." Biogeosciences 14, no. 8 (April 24, 2017): 2089–100. http://dx.doi.org/10.5194/bg-14-2089-2017.
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Abstract. Antarctic palaeoclimate evolution and vegetation history after the formation of a continent-scale cryosphere at the Eocene–Oligocene boundary, 33.9 million years ago, has remained a matter of controversy. In particular, the reconstruction of terrestrial climate and vegetation has been strongly hampered by uncertainties in unambiguously identifying non-reworked as opposed to reworked sporomorphs that have been transported into Antarctic marine sedimentary records by waxing and waning ice sheets. Whereas reworked sporomorph grains over longer non-successive geological timescales are easily identifiable within younger sporomorph assemblages (e.g. Permian sporomorphs in Pliocene sediments), distinguishing non-reworked from reworked material in palynological assemblages over successive geological time periods (e.g. Eocene sporomorphs in Oligocene sediments) has remained problematic. This study presents a new quantitative approach to identifying non-reworked pollen assemblages in marine sediment cores from circum-Antarctic waters. We measured the fluorescence colour signature, including red, green, and blue fluorescence; brightness; intensity; and saturation values of selected pollen and spore taxa from Eocene, Oligocene, and Miocene sediments from the Wilkes Land margin Site U1356 (East Antarctica) recovered during Integrated Ocean Drilling Program (IODP) Expedition 318. Our study identified statistically significant differences in red-fluorescence values of non-reworked sporomorph taxa against age. We conclude that red fluorescence is a reliable parameter for identifying the presence of non-reworked pollen and spores in Antarctic marine sediment records from the circum-Antarctic realm that are influenced by glaciation and extensive reworking. Our study provides a new tool to accurately reconstruct Cenozoic terrestrial climate change on Antarctica using fossil pollen and spores.
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Wang, Ya Jun, Feng Jin, Chu Han Zhang, and Jun Wang. "Primary Physical-Mechanical Characteristics on Marine Sediments from Zhoushan Seas in Sino Mainland." Applied Mechanics and Materials 275-277 (January 2013): 273–77. http://dx.doi.org/10.4028/www.scientific.net/amm.275-277.273.
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Marine sediment laboratory test model was developed by excavation on site and application of GDS triaxial loading system. The grading characteristics on representative soft marine soil from Wushitang (MS1) and Dongsha Seas (MS2) were studied and the key evaluating indicators, i.e., curvature coefficient CC and non-uniform coefficient Cu were analyzed. Based on the systematically physical-mechanical test data, the constitutive model on step deviatonic-stress and strain development was researched. The result shows the exponential mapping relationship is applicable for stress-strain constitution. The fluid-solid coupling non-linear function was established by spatial pore pressure surface fitting. The key consolidation treatment for soft marine sediments was discovered.
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Lelono, Eko Budi. "POLLEN RECORD OF THE PERMIAN MARINE SEDIMENTS FROM WEST TIMOR." Scientific Contributions Oil and Gas 40, no. 2 (September 18, 2018): 75–84. http://dx.doi.org/10.29017/scog.40.2.42.
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This is the fi rst publication to present palynological study on the Permian marine sediments of West Timor. This is aimed to evaluate its palynomorph content. Similar studies have been performed on the Permian sediments which mostly focus on non-marine sediments. 15 surface samples were collected from Lilana river outcrop which comprises the alternation of calcareous shale and sandstone. This outcrop is assumed to represent some parts of Bisane Formation. Standard preparation methods were employed to extract palynomorphs including acid maceration and oxidation. This study applies quantitative method which requires counting of palynomorphs in each sample. This study provides low to moderate pollen recovery which mostly consists of striate and non-striate bisaccates as well as trilete monosaccates. The age restricted taxa appearing in the non-marine sediments also present in the studied samples to mark Permian age such as Protohaploxypinus samoilovichi, Lunatisporites pellucidus, Falcisporites australis, Plicatipollenites malabarensis and Cannanoropollis janakii. On the other hand, common occurrence of marine dinofl agellates of Dapsilidium langii and Veryhachim reductum combined with abundant macrofossil of chrinoids confi rm a shallow marine paleoenvironment. Common green algae of Tasmanites sp. is a firmed evidence for the appearance of potential source rock of hydrocarbon within the Permian shallow marine sediments of West Timor.
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Melucci, Dora, Alessandro Zappi, Francesca Poggioli, Pietro Morozzi, Federico Giglio, and Laura Tositti. "ATR-FTIR Spectroscopy, a New Non-Destructive Approach for the Quantitative Determination of Biogenic Silica in Marine Sediments." Molecules 24, no. 21 (October 31, 2019): 3927. http://dx.doi.org/10.3390/molecules24213927.
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Biogenic silica is the major component of the external skeleton of marine micro-organisms, such as diatoms, which, after the organisms death, settle down onto the seabed. These micro-organisms are involved in the CO2 cycle because they remove it from the atmosphere through photosynthesis. The biogenic silica content in marine sediments, therefore, is an indicator of primary productivity in present and past epochs, which is useful to study the CO2 trends. Quantification of biosilica in sediments is traditionally carried out by wet chemistry followed by spectrophotometry, a time-consuming analytical method that, besides being destructive, is affected by a strong risk of analytical biases owing to the dissolution of other silicatic components in the mineral matrix. In the present work, the biosilica content was directly evaluated in sediment samples, without chemically altering them, by attenuated total reflection Fourier transform infrared (ATR-FTIR) spectroscopy. Quantification was performed by combining the multivariate standard addition method (MSAM) with the net analyte signal (NAS) procedure to solve the strong matrix effect of sediment samples. Twenty-one sediment samples from a sediment core and one reference standard sample were analyzed, and the results (extrapolated concentrations) were found to be comparable to those obtained by the traditional wet method, thus demonstrating the feasibility of the ATR-FTIR-MSAM-NAS approach as an alternative method for the quantification of biosilica. Future developments will cover in depth investigation on biosilica from other biogenic sources, the extension of the method to sediments of other provenance, and the use higher resolution IR spectrometers.
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Zheng, Yan, Robert F. Anderson, Alexander van Geen, and Martin Q. Fleisher. "Preservation of particulate non-lithogenic uranium in marine sediments." Geochimica et Cosmochimica Acta 66, no. 17 (September 2002): 3085–92. http://dx.doi.org/10.1016/s0016-7037(01)00632-9.
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Tong, Fei, Guobao Chen, Xue Feng, Yan Liu, and Pimao Chen. "The Effect of the Artificial Reef on the Structure and Function of Sediment Bacterial Community." Sustainability 14, no. 22 (November 8, 2022): 14728. http://dx.doi.org/10.3390/su142214728.
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The bacterial community in sediment is sensitive to artificial disturbance, and they respond differently to human disturbance, such as changing the nutrient cycling and energy flow in marine ecosystems. However, little is known about the dynamics and distribution of bacterial community structures in marine sediments and potential biogeochemical functions during the long-time succession in marine ranching. In the present study, we compared the dynamics of the bacterial composition and potential biogeochemical functions of sediment to ten years (TR) and one-year new artificial reef (NR) areas using metagenomic next-generation sequencing technology. Results revealed that NR reduces the Pielou’s evenness and Shannon index. Similarly, nonmetric multidimensional scaling showed that the beta diversity of sediment bacterial communities in NR significantly differed between TR and non-artificial reef areas. Previously, TR biomarkers were frequently associated with organic matter decomposing and assimilating in the organically enriched sediments (i.e., Acinetobacter). The soluble reactive phosphate (SRP) and total phosphorus (TP) concentrations were thought to be the primary driving forces in shaping the microbial community in sediment. Pseudomonas, Lactobacillus, and Ralstonia have a significant positive correlation with SRP, TP, nitrate, and TN, but a negative association with pH, Salinity, Hg, and depth. NR was found to have more negative correlation nodes, indicating that taxa face more competition or predation press. Vibrio served as the module-hubs in the network in all areas. In addition, chemoheterotrophy, aerobic chemoheterotrophy, and fermentation were the three most prominent functions of the three areas, accounting for 59.96% of the relative abundance of the functional annotation. Different bacteria in sediments may change the amount of biogeochemical cycle in the marine ranching ecosystem. These findings can increase our understanding of the succession of the microecosystem for the marine ranching sedimentary environment by revealing how artificial reefs affect the indigenous sediment bacterial community and their responses to environmental variation.
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Chen, Xian, Xiaoming Sun, Zhongwei Wu, Yan Wang, Xiao Lin, and Hongjun Chen. "Mineralogy and Geochemistry of Deep-Sea Sediments from the Ultraslow-Spreading Southwest Indian Ridge: Implications for Hydrothermal Input and Igneous Host Rock." Minerals 11, no. 2 (January 29, 2021): 138. http://dx.doi.org/10.3390/min11020138.
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Detailed mineralogical and geochemical characteristics of typical surface sediments and hydrothermal deposits collected from the ultraslow-spreading Southwest Indian Ridge (SWIR) were studied by high-resolution XRD, SEM-EDS, XRF, and ICP-MS. The SWIR marine samples can be generally classified into two main categories: surface sediment (biogenic, volcanic) and hydrothermal-derived deposit; moreover, the surface sediment can be further classified into metalliferous and non-metalliferous based on the metalliferous sediment index (MSI). The chemical composition of biogenic sediment (mainly biogenic calcite) was characterized by elevated contents of Ca, Ba, Rb, Sr, Th, and light rare earth elements (LREE), while volcanic sediment (mainly volcanogenic debris) was relatively enriched in Mn, Mg, Al, Si, Ni, Cr, and high field strength elements (HFSEs). By contrast, the hydrothermal-derived deposit (mainly pyrite-marcasite, chalcopyrite-isocubanite, and low-temperature cherts) contained significantly higher contents of Fe, Cu, Zn, Pb, Mn, Co, Mo, Ag, and U. In addition, the metalliferous surface sediment contained a higher content of Cu, Mn, Fe, Co, Mo, Ba, and As. Compared with their different host (source) rock, the basalt-hosted marine sediments contained higher contents of Ti–Al–Zr–Sc–Hf and/or Mo–Ba–Ag; In contrast, the peridotite-hosted marine sediments were typically characterized by elevated concentrations of Mg–Cu–Ni–Cr and/or Co–Sn–Au. The differences in element enrichment and mineral composition between these sediment types were closely related to their sedimentary environments (e.g., near/far away from the vent sites) and inherited from their host (source) rock. Together with combinations of certain characteristic elements (such as Al–Fe–Mn and Si–Al–Mg), relict hydrothermal products, and diagnostic mineral tracers (e.g., nontronite, SiO2(bio), olivine, serpentine, talc, sepiolite, pyroxene, zeolite, etc.), it would be more effective to differentiate the host rock of deep-sea sediments and to detect a possible hydrothermal input.
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Hamid Al-Jaberi, Mohanad. "Clay Minerals Variations in Quaternary Sediments of Basrah City-Iraq." Earth Science Research 6, no. 2 (April 8, 2017): 41. http://dx.doi.org/10.5539/esr.v6n2p41.
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Mineralogical and chemical analysis of two well cutting in quaternary sediments at Basrah city. This study have been focused on the quaternary clay minerals variations which give a clear indication to marine transgression and or / regression in Hammar formation. Kaolinite, Illite, Palygoreskite, Illite-Palygorestike mixed layer, Chlorite, Montmorillonite, Vermiculte, and mixed layers of Illite- Smectite are the most quantitatively important phyllosilicates in soil studies in both boreholes. The mineralogical composition of cutting sediments shows significant variability in the different size fractions and depth distribution. Chlorite and kaolinite minerals were increase in the fine grain size especially in the clayey silt, whereas montmoriolllinite and vermiculite minerals were increase in coarse grains especially in silty sand texture. Kaolinite decrease in abundance with depth, which give indicative of a transition from non-marine in quaternary recent sediment ( fresh or brackish water silt) to marine facies in quaternary Hammar formation ( marine shelly silt) during last transgression of quaternary. Palygoreskite mineral percentages increasing at depths 27 and 28 meter , after decreased at 30, 32, 35 , and 40 m respectively , which give data indication that early quaternary marine transgression happened in 32m , and center of quaternary marine transgression detected in 27 and 28 meters , while late marine transgression detected in 17 m , and all of these represent by Hammar formation. Soil ageing also caused to downward increase of montmorillonite suggest to climate became more arid during the early quaternary. Variations ratio of montmorillonite versus kaolinite can be indicated to climatic fluctuation. Illite-Semectite featured indicates changes in both sediment source and paleoclimate. Illite transformation for Illite-Palygoreskite mixed layers with ageing. Vermiculite has strong susceptibility to increase with age. SiO₂, Al₂O₃, CaO, MgO, K₂O, and Fe₂O₃ were the major oxides that identified in present study and used as indicated of clay minerals in studied sediments.
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Fritz, William J. "Plant Taphonomy in Areas of Explosive Volcanism." Notes for a Short Course: Studies in Geology 15 (1986): 1–9. http://dx.doi.org/10.1017/s0271164800001299.
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Coarse-grained volcaniclastic sediments are a common part of the non-marine geologic record along most continental margins. Many of these volcanic sediment units contain well-preserved assemblages of fossil plants. Because much of the work on depositional environments, dating, correlations and paleoenvironments has been derived from studies of plants, it is important to understand the processes that incorporate the plants into the volcaniclastic sediments. In this paper I plan to concentrate on processes that bury and preserve trees, logs and stumps.
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Suliman, Ibrahim I., and Khalid Alsafi. "Radiological Risk to Human and Non-Human Biota Due to Radioactivity in Coastal Sand and Marine Sediments, Gulf of Oman." Life 11, no. 6 (June 11, 2021): 549. http://dx.doi.org/10.3390/life11060549.
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Natural and 137Cs radioactivity in coastal marine sediment samples was measured using gamma spectrometry. Samples were collected at 16 locations from four beaches along the coastal area of Muscat City, Gulf of Oman. Radioactivity in beach sand was used to estimate the radiological risk parameters to humans, whereas the radioactivity in marine sediments was used to assess the radiological risk parameters to non-human biota, using the ERICA Tool. The average radioactivity concentrations (Bqkg−1) of 226Ra, 232Th, 40K, 210Pb and 137Cs in sediments (sand) were as follows: 16.2 (16.3), 34.5(27.8), 54.7 (45.6), 46.8 (44.9) and 0.08 (0.10), respectively. In sand samples, the estimated average indoor (Din) and outdoor (Dout) air absorbed dose rates due to natural radioactivity were 49.26 and 27.4 and the total effective dose (AEDTotal; µSvy−1) ranged from 150.2 to 498.9 (average: 275.2). The measured radioactivity resulted in an excess lifetime cancer risk (ELCR) in the range of 58–203 (average: 111) in and an average gonadal dose (AGD; µGy.y−1) ranged from 97.3 to 329.5 (average: 181.1). Total dose rate per marine organism ranged from 0.035 µGy h−1 (in zooplankton) to 0.564 µGy h−1 (in phytoplankton). The results showed marine sediments as an important source of radiation exposure to biota in the aquatic environment. Regular monitoring of radioactivity levels is vital for radiation risk confinement. The results provide an important radiological risk profile parameter to which future radioactivity levels in marine environments can be compared.
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Demarco, Larissa Felicidade Werkhauser, Antonio Henrique da Fontoura Klein, and Jorge Antonio Guimarães de Souza. "Marine substrate response from the analysis of seismic attributes in CHIRP sub-bottom profiles." Brazilian Journal of Oceanography 65, no. 3 (September 2017): 332–45. http://dx.doi.org/10.1590/s1679-87592017124306503.
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Abstract This paper presents an evaluation of the response of seismic reflection attributes in different types of marine substrate (rock, shallow gas, sediments) using seafloor samples for ground-truth statistical comparisons. The data analyzed include seismic reflection profiles collected using two CHIRP subbottom profilers (Edgetech Model 3100 SB-216S), with frequency ranging between 2 and 16 kHz, and a number (38) of sediment samples collected from the seafloor. The statistical method used to discriminate between different substratum responses was the non-parametric Kruskal-Wallis analysis, carried out in two steps: 1) comparison of Seismic Attributes between different marine substrates (unconsolidated sediments, rock and shallow gas); 2) comparison of Seismic Attributes between different sediment classes in seafloors characterized by unconsolidated sediments (subdivided according to sorting). These analyses suggest that amplitude-related attributes were effective in discriminating between sediment and gassy/rocky substratum, but did not differentiate between rocks and shallow gas. On the other hand, the Instantaneous Frequency attribute was effective in differentiating sediments, rocks and shallow gas, with sediment showing higher frequency range, rock an intermediate range, and shallow gas the lowest response. Regarding grain-size classes and sorting, statistical analysis discriminated between two distinct groups of samples, the SVFS (silt and very fine sand) and the SFMC (fine, medium and coarse sand) groups. Using a Spearman coefficient, it was found that the Instantaneous Amplitude was more efficient in distinguishing between the two groups. None of the attributes was able to distinguish between the closest grain size classes such as those of silt and very fine sand.
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van de Velde, Sebastiaan J., Rebecca K. James, Ine Callebaut, Silvia Hidalgo-Martinez, and Filip J. R. Meysman. "Bioturbation has a limited effect on phosphorus burial in salt marsh sediments." Biogeosciences 18, no. 4 (February 25, 2021): 1451–61. http://dx.doi.org/10.5194/bg-18-1451-2021.
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Abstract. It has been hypothesized that the evolution of animals during the Ediacaran–Cambrian transition stimulated the burial of phosphorus in marine sediments. This assumption is centrally based on data compilations from marine sediments deposited under oxic and anoxic bottom waters. Since anoxia excludes the presence of infauna and sediment reworking, the observed differences in P burial are assumed to be driven by the presence of bioturbators. This reasoning however ignores the potentially confounding impact of bottom-water oxygenation on phosphorus burial. Here, our goal is to test the idea that bioturbation increases the burial of organic and inorganic phosphorus (Porg and Pinorg, respectively) while accounting for bottom-water oxygenation. We present solid-phase phosphorus speciation data from salt marsh ponds with and without bioturbation (Blakeney salt marsh, Norfolk, UK). In both cases, the pond sediments are exposed to oxygenated bottom waters, and so the only difference is the presence or absence of bioturbating macrofauna. Our data reveal that the rate of Porg and Pinorg burial are indistinguishable between bioturbated and non-bioturbated sediments. A large terrestrial fraction of organic matter and higher sedimentation velocity than generally found in marine sediments (0.3 ± 0.1 cm yr−1) may partially impact these results. However, the absence of a clear effect of bioturbation on total P burial puts into question the presumed importance of bioturbation for phosphorus burial.
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Kao, S. J., R. G. Hilton, K. Selvaraj, M. Dai, F. Zehetner, J. C. Huang, S. C. Hsu, et al. "Preservation of terrestrial organic carbon in marine sediments off shore Taiwan: mountain building and atmospheric carbon dioxide sequestration." Earth Surface Dynamics Discussions 1, no. 1 (July 17, 2013): 177–206. http://dx.doi.org/10.5194/esurfd-1-177-2013.
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Abstract. Geological sequestration of atmospheric carbon dioxide (CO2) can be achieved by the erosion of organic carbon (OC) from the terrestrial biosphere and its burial in long-lived marine sediments. Rivers on mountain islands of Oceania in the western Pacific have very high rates of OC export to the ocean, yet its preservation offshore remains poorly constrained. Here we use the OC content (Corg, %), radiocarbon (Δ14Corg) and stable isotope (δ13Corg) composition of sediments offshore Taiwan to assess the fate of terrestrial OC. We account for rock-derived fossil OC to assess the preservation of OC eroded from the terrestrial biosphere (non-fossil OC) during flood discharges (hyperpycnal river plumes) and when river inputs are dispersed more widely (hypopycnal). The Corg, Δ14Corg and δ13Corg of marine sediment traps and cores indicate that during flood discharges, terrestrial OC is transferred efficiently to the deep ocean and accumulates offshore with little evidence for terrestrial OC loss. In marine sediments fed by dispersive river inputs, the Corg, Δ14Corg and δ13Corg are consistent with mixing of marine OC and terrestrial OC and suggest that efficient preservation of terrestrial OC (> 70%) is also associated with hypopycnal delivery. Re-burial of fossil OC is pervasive. Our findings from Taiwan suggest that erosion and marine burial of terrestrial non-fossil OC may sequester > 8 TgC yr−1 across Oceania, a significant geological CO2 sink which requires better constraint. We postulate that mountain islands of Oceania provide strong link between tectonic uplift and the carbon cycle, one moderated by the climatic variability that controls terrestrial OC delivery to the ocean.
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Wyatt, Philip H. "Amino Acid Evidence Indicating Two or More Ages of Pre-Holocene Nonglacial Deposits In Hudson Bay Lowland, Northern Ontario." Note 44, no. 3 (December 18, 2007): 389–93. http://dx.doi.org/10.7202/032838ar.
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ABSTRACT Amino acid studies have identified pre-Holocene non-glacial sediments in the Hudson Lowland which are significantly younger than Bell Sea sediments of the Missinaibi Formation. This younger unit is represented by marine sediments on the Severn and Abitibi rivers. Buried organic material on Beaver River is correlated with the younger Severn and Abitibi river marine sediments based on amino acid evidence. Assuming that Bell Sea sediments are of last interglacial (130-120 ka) age, the younger nonglacial sediments may have been deposited late in 18O stage 5 (80-75 ka). Paleoecologic studies of the Beaver River organics indicate climate at least as warm as present.
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McLoughlin, Stephen. "Plant fossil distributions in some Australian Permian non-marine sediments." Sedimentary Geology 85, no. 1-4 (May 1993): 601–19. http://dx.doi.org/10.1016/0037-0738(93)90104-d.
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Castañeda, Rowshyra A., Suncica Avlijas, M. Anouk Simard, and Anthony Ricciardi. "Microplastic pollution in St. Lawrence River sediments." Canadian Journal of Fisheries and Aquatic Sciences 71, no. 12 (December 2014): 1767–71. http://dx.doi.org/10.1139/cjfas-2014-0281.
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Although widely detected in marine ecosystems, microplastic pollution has only recently been documented in freshwater environments, almost exclusively in surface waters. Here, we report microplastics (polyethylene microbeads, 0.40–2.16 mm diameter) in the sediments of the St. Lawrence River. We sampled 10 freshwater sites along a 320 km section from Lake St. Francis to Québec City by passing sediment collected from a benthic grab through a 500 μm sieve. Microbeads were discovered throughout this section, and their abundances varied by four orders of magnitude across sites. Median and mean (±1 SE) densities across sites were 52 microbeads·m−2 and 13 832 (±13 677) microbeads·m−2, respectively. The highest site density was 1.4 × 105 microbeads·m−2 (or 103 microbeads·L−1), which is similar in magnitude to microplastic concentrations found in the world’s most contaminated marine sediments. Mean diameter of microbeads was smaller at sites receiving municipal or industrial effluent (0.70 ± 0.01 mm) than at non-effluent sites (0.98 ± 0.01 mm), perhaps suggesting differential origins. Given the prevalence and locally high densities of microplastics in St. Lawrence River sediments, their ingestion by benthivorous fishes and macroinvertebrates warrants investigation.
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Lelono, Eko Budi, L. Nugrahaningsih, and Dedi Kurniadi. "PERMO-TRIASSIC PALYNOLOGY OF THE WEST TIMOR." Scientific Contributions Oil and Gas 39, no. 1 (May 1, 2016): 1–13. http://dx.doi.org/10.29017/scog.39.1.529.
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Fifteen surface samples were examined to analyze palynology of the Permo-Triassic sediments of West Timor. The studied samples were collected from the clastic sediment of Bisane Formation which is considered to be the oldest formation. It derives from the Australian continent (Gondwana) following thecollision with the Banda volcanic arc. The Bisane Formation generally comprises thick calcareous sandstone (0.3-5 meters) with shale alternation and abundant marine microfossil of Chrinoid. The appearance of Chrinoid may indicate Permian age and shallow marine environment. Meanwhile, other Bisane sediment shows different lithology in which it is composed of the intercalation of non-calacreous, dark gray to black shale and siltstone showing papery structure and rich in sulphur. Generally, palynological assemblage of the studied samples characterises Permo-Triassic age as indicated by the existence of common striate-bisaccate pollen including Protohaploxypinus samoilovichii, P. fuscus, P. goraiensis, Striatopodocarpidites phaleratus, Pinuspollenites globosaccus and Lunatisporites pellucidus. However, the appearance of trilete-monosaccate spores of Plicatipollenites malabarensis and Cannanoropollis janakii within the non-calcareous shale samples de nes the age as Permian or older for these samples. Interestingly, marine dino agellates appear to mark calcareous samples suggesting the in uence of a marine environment. They disappear from the non-calcareous samples indicating a freshwater environment. By integrating this palynological analysis and Permian tectonic event which is marked by rifting, it can be interpreted that the non-calcareous samples were formed during early syn-rift as evidenced by the occurrence of freshwater deposit (may be lacustrine). Subsequently, following sea level rises during post rift, the depositional environment shifted to shallow marine as indicated by the existence of calcareous Permo-Triassic samples. If this is the case, the appearance of Permo-Triassic sediments provides an opportunity to nd a new petroleum system in the Paleozoic series of West Timor. Source rock is represented by black shale, whereas reservoir is represented by thick sandstone.
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Sun, Shuwen, Enno Schefuß, Stefan Mulitza, Cristiano M. Chiessi, André O. Sawakuchi, Matthias Zabel, Paul A. Baker, Jens Hefter, and Gesine Mollenhauer. "Origin and processing of terrestrial organic carbon in the Amazon system: lignin phenols in river, shelf, and fan sediments." Biogeosciences 14, no. 9 (May 17, 2017): 2495–512. http://dx.doi.org/10.5194/bg-14-2495-2017.
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Abstract. The Amazon River transports large amounts of terrestrial organic carbon (OCterr) from the Andean and Amazon neotropical forests to the Atlantic Ocean. In order to compare the biogeochemical characteristics of OCterr in the fluvial sediments from the Amazon drainage basin and in the adjacent marine sediments, we analysed riverbed sediments from the Amazon mainstream and its main tributaries as well as marine surface sediments from the Amazon shelf and fan for total organic carbon (TOC) content, organic carbon isotopic composition (δ13CTOC), and lignin phenol compositions. TOC and lignin content exhibit positive correlations with Al ∕ Si ratios (indicative of the sediment grain size) implying that the grain size of sediment discharged by the Amazon River plays an important role in the preservation of TOC and leads to preferential preservation of lignin phenols in fine particles. Depleted δ13CTOC values (−26.1 to −29.9 ‰) in the main tributaries consistently correspond with the dominance of C3 vegetation. Ratios of syringyl to vanillyl (S ∕ V) and cinnamyl to vanillyl (C ∕ V) lignin phenols suggest that non-woody angiosperm tissues are the dominant source of lignin in the Amazon basin. Although the Amazon basin hosts a rich diversity of vascular plant types, distinct regional lignin compositions are not observed. In the marine sediments, the distribution of δ13CTOC and Λ8 (sum of eight lignin phenols in organic carbon (OC), expressed as mg/100 mg OC) values implies that OCterr discharged by the Amazon River is transported north-westward by the North Brazil Current and mostly deposited on the inner shelf. The lignin compositions in offshore sediments under the influence of the Amazon plume are consistent with the riverbed samples suggesting that processing of OCterr during offshore transport does not change the encoded source information. Therefore, the lignin compositions preserved in these offshore sediments can reliably reflect the vegetation in the Amazon River catchment. In sediments from the Amazon fan, low lignin content, relatively depleted δ13CTOC values and high (Ad ∕ Al)V ratios indicating highly degraded lignin imply that a significant fraction of the deposited OCterr is derived from petrogenic (sourced from ancient rocks) sources.
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Fonti, Viviana, Antonio Dell’Anno, and Francesca Beolchini. "Biogeochemical Interactions In The Application Of Biotechnological Strategies To Marine Sediments Contaminated With Metals." Nova Biotechnologica et Chimica 14, no. 1 (June 1, 2015): 12–31. http://dx.doi.org/10.1515/nbec-2015-0010.
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AbstractSediment contamination in coastal areas with high anthropogenic pressure is a widespread environmental problem. Metal contaminants are of particular concern, since they are persistent and cannot be degraded. Microorganisms can influence metal mobility in the sediment by several direct and indirect processes. However, the actual fate of metals in the environment is not easily predictable and several biogeochemical constraints affect their behaviour. In addition, the geochemical characteristics of the sediment play an important role and the general assumptions for soils or freshwater sediments cannot be extended to marine sediments. In this paper we analysed the correlation between metal mobility and main geochemical properties of the sediment. Although the prediction of metal fate in sediment environment, both forex-situbioleaching treatments andin-situbiostimulation strategies, appears to require metal-specific and site-specific tools, we found that TOM and pH are likely the main variables in describing and predicting Zn behaviour. Arsenic solubilisation/increase in mobility appears to correlate positively with carbonate content. Cd, Pb and Ni appear to require multivariate and/or non-linear approaches.
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Lang, S. C., P. Grech, R. Root, A. Hill, and D. Harrison. "THE APPLICATION OF SEQUENCE STRATIGRAPHY TO EXPLORATION AND RESERVOIR DEVELOPMENT IN THE COOPER-EROMANGA-BOWEN-SURAT BASIN SYSTEM." APPEA Journal 41, no. 1 (2001): 223. http://dx.doi.org/10.1071/aj00011.
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The application of sequence stratigraphy to non-marine strata in intracratonic basins is still in its infancy, however, the predominantly non-marine Cooper- Eromanga-Surat-Bowen basin system of Eastern Australia provides an excellent opportunity to demonstrate how sequence stratigraphic concepts can be applied to non-marine successions to assist with exploration and reservoir development. The key to applying sequence stratigraphic concepts in non-marine basins lies in understanding the role of alluvial sediment accommodation relative to sediment supply. Accommodation is created by a combination of tectonic subsidence, compaction and changing water tables in floodplain lakes, marshlands and peat mires. If the alluvial basin is directly connected to the marine system then eustacy may influence accommodation in the lower reaches of the alluvial network, but its effect will significantly diminish upstream depending on the slope. Climate change will, however, have an impact on fluvial discharge, rising water tables, floodplain lake levels, and sediment flux. For sediments to accumulate, accommodation must be positive, whereas negative accommodation leads to erosion. Fluvial accommodation is, therefore, comparable with the concept of base-level. During an episode of basin-wide tectonic uplift or tilting, falling base-level (negative accommodation) leads to widespread erosion on the basin margins or over intra-basinal highs, and an unconformity equivalent to a sequence boundary develops. If followed by a period of low accommodation, rivers rework much of their floodplain, resulting in a sheetlike, amalgamated succession of predominantly sandy bedload deposits of high nett to gross, equivalent to an alluvial lowstand. Further downstream, lowstand deltas may form in the lakes.
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Angelidis, Michael O. "The impact of urban effluents on the coastal marine environment of Mediterranean islands." Water Science and Technology 32, no. 9-10 (November 1, 1995): 85–94. http://dx.doi.org/10.2166/wst.1995.0673.
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The impact of the urban effluents of Mytilene (Lesvos island, Greece) on the receiving coastal marine environment, was evaluated by studying the quality of the city effluents (BOD5, COD, SS, heavy metals) and the marine sediments (grain size, organic matter, heavy metals). It was found that the urban effluents of Mytilene contain high organic matter and suspended particle load because of septage discharge into the sewerage network. Furthermore, although the city does not host important industrial activity, its effluents contain appreciable metal load, which is mainly associated with the particulate phase. The city effluents are discharged into the coastal marine environment and their colloidal and particulate matter after flocculation settles to the bottom, where is incorporated into the sediments. Over the years, the accumulation of organic matter and metals into the harbour mud has created a non-point pollution source in the relatively non-polluted coastal marine environment of the island. Copper and Zn were the metals which presented the higher enrichment in the sediments of the inner harbour of Mytilene.
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Fiket, Željka, Marina Mlakar, and Goran Kniewald. "Distribution of Rare Earth Elements in Sediments of the Marine Lake Mir (Dugi Otok, Croatia)." Geosciences 8, no. 8 (August 10, 2018): 301. http://dx.doi.org/10.3390/geosciences8080301.
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The Lake Mir represents a small, isolated, and shallow marine lake situated in the south-eastern part of the Dugi otok Island, in a karstic landscape of the eastern Adriatic coast. The surrounding karstic background, with occasional occurrences of red soil, characterizes the sediments in the lake as coarse grained and carbonate rich. Previous studies suggested the prevailing influence of the lake bathymetry, that is, the proportion of carbonates and grain size characteristics of the sediments, on the variability of the element composition of the lake sediments. To confirm previous assumptions and obtain a better understanding of the factors influencing sediment composition of this marine lake, the distribution of rare earth elements in sediments of the Lake Mir and the nearby Telašćica Bay, as well as surrounding soils, was investigated. In the lake sediments, the sum of rare earth elements, including Y (hereinafter referred as ΣREY), ranged from 10.6 mg kg−1 to 25.3 mg kg−1; in the Telašćica Bay sediments, ΣREY were higher compared to the lake and ranged from 56.4 mg kg−1 to 85.2 mg kg−1, while the highest ΣREY, from 83.3 mg kg−1 to 227 mg kg−1, were observed in soils surrounding the lake. Despite the difference in the levels of the rare earth elements, the REY normalized patterns and associated fractionation parameters (ΣLREE/ΣHREE, (La/Yb)N, and (Nd/Yb)N) showed similarities between the lake sediments and the surrounding soils, confirming a significant influence of local lithology on the lake composition. The results of the statistical analysis, on the other hand, suggest the contribution of both the carbonate (e.g., calcite) and non-carbonate minerals (i.e., alumosilicates and Al–Fe-hydroxides) on the total REY content in the lake sediments.
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Lelono, Eko B., Mufdi Firdaus, and Tri Bambang SR. "Palaeoenvironments Of The Permian-Cretaceous Sediments Of The Bintuni Bay, Papua." Scientific Contributions Oil and Gas 33, no. 1 (February 15, 2022): 71–83. http://dx.doi.org/10.29017/scog.33.1.810.
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This paper presents a part of the result of Lemigas in-house research entitled Paleogeography and Hydrocarbon Potentiality of the pre-Tertiary Sediment of the Bintuni Basin, Papua, which is financially supported by the Government through a project so called DIPA 2009. In addition, this paper specifically discusses a palaeoenvironment of the Late Permian-Cretaceous sediment of the Bintuni Bay based on biostratigraphy. Data used in this paper is mostly secondary data obtained from National Data Center and an oil company which is therefore, classified as a confidential information. Paleoenvironment appeared in a non-marine setting during Permian-Triassic to form Ainim Formation in which, shale of this formation acts as a primary sourcerock for the studied area. Early Jurassic is characterised by a non-deposition, whilst Middle Jurassic is indicated by the occurrence of non-marine environment to deposit fluvial sandstone of the Lower Kembelangan Formation which is considered to be a main reservoir. Subsequently, environment shifted to the marine setting where deep marine shale occurred to form caprock. Mean while, the Early Cretaceous sediment disappears from the studied area suggesting massive erosion. Finally, depositional environment took place in the marine setting during the Late Cretaceous resulting in the formation of deep marine shale of Jass Formation which may contribute as a caprock in the element of petroleum system
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Sanz-Lázaro, C., T. Valdemarsen, and M. Holmer. "Effects of global climate change and organic pollution on nutrient cycling in marine sediments." Biogeosciences Discussions 12, no. 1 (January 5, 2015): 21–49. http://dx.doi.org/10.5194/bgd-12-21-2015.
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Abstract. Increasing ocean temperature due to climate change is an important anthropogenic driver of ecological change in coastal systems, where sediments play a major role in nutrient cycling. Our ability to predict ecological consequences of climate change is enhanced by simulating real scenarios especially when the interactions among drivers may not be just additive. Based on predicted climate change scenarios, we tested the effect of temperature and organic pollution on nutrient release from coastal sediments to the water column in a mesocosm experiment. PO43− release rates from sediments followed the same trends as organic matter mineralization rates, and increased linearly with temperature and were significantly higher under organic pollution than under non-polluted conditions. NH4+ release only increased significantly when the temperature rise was above 6 °C, and was significantly higher in organic polluted compared to non-polluted sediments. Nutrient release to the water column was only a fraction from the mineralized organic matter, suggesting PO43− retention and NH4+ oxidation in the sediment. Bioturbation and bioirrigation appeared to be key processes responsible of this behaviour. Considering that the primary production of most marine basins is N-limited, the excess release of NH4+ at temperature rise >6 ° could enhance water column primary productivity, which may lead to the deterioration of the environmental quality. Climate change effects are expected to be accelerated in areas affected by organic pollution.
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Labutis, V. R., A. D. Ruddock, and A. P. C. alcraft. "STRATIGRAPHY OF THE SOUTHERN SAHUL PLATFORM." APPEA Journal 38, no. 1 (1998): 115. http://dx.doi.org/10.1071/aj97006.
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This study of the southern Sahul Platform area in the Zone of Cooperation is based on the identification of depositional sequences, their distribution and relationship to structuring events in order to predict the locations of favourable combinations of source, seal and reservoir facies with increased confidence. A sequence stratigraphic approach integrating well logs, palynology and seismic data was used to identify and map significant seismic horizons such as the Aptian and Tithonian unconformities.Early to Middle Jurassic sediments were deposited in a broad, northeast-southwest oriented sag basin with a northeastward sediment transport direction. Depositional environments range from non-marine to marginal marine in the Plover Formation to the shallow marine sediments of the Elang Formation. The Elang Formation, comprising two depositional sequences, represents the last of the sediments deposited before the Breakup Unconformity. These formations comprise the dominant reservoir facies, containing a number of oil and gas discoveries. Porosity degradation occurs in Jurassic reservoirs below 3,360 m.The Callovian Breakup Unconformity resulted in the initiation of the narrow, confined depocentres of the Sahul Syncline, Malita Graben and a series of east-west troughs. The Sahul Platform and Londonderry High comprise the flanks of these depocentres but were originally located within the depocentre of the Early to Middle Jurassic sag basin. The Flamingo Syncline is a younger feature developed in the Albian.Late Jurassic and Early Cretaceous sediments are confined mainly to the Sahul Syncline and Malita Graben and are absent or represented by thin, condensed sections on the flanking highs. The condensed sections on horst blocks are a result of sediment bypass rather than considerable erosion. Reservoir facies of Tithonian-Berriasian age are interpreted to occur within east-west troughs constituting another reservoir section apart from the Bathonian-Callovian sediments. Wells distant from the Sahul Syncline and Malita Graben, have encountered hydrocarbons, indicating that the area contains mature source rocks, capable of charging traps away from the immediate vicinity of the depocentres.
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Yang, Hailin, Shan Yu, and Hailong Lu. "Iron-Coupled Anaerobic Oxidation of Methane in Marine Sediments: A Review." Journal of Marine Science and Engineering 9, no. 8 (August 13, 2021): 875. http://dx.doi.org/10.3390/jmse9080875.
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Anaerobic oxidation of methane (AOM) is one of the major processes of oxidizing methane in marine sediments. Up to now, extensive studies about AOM coupled to sulfate reduction have been conducted because SO42− is the most abundant electron acceptor in seawater and shallow marine sediments. However, other terminal electron acceptors of AOM, such as NO3−, NO2−, Mn(IV), Fe(III), are more energetically favorable than SO42−. Iron oxides, part of the major components in deep marine sediments, might play a significant role as an electron acceptor in the AOM process, mainly below the sulfate–methane interface, mediated by physiologically related microorganisms. Iron-coupled AOM is possibly the dominant non-sulfate-dependent AOM process to consume methane in marine ecosystems. In this review, the conditions for iron-coupled AOM are summarized, and the forms of iron oxides as electron acceptors and the microbial mechanisms are discussed.
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Hrischeva, E., and S. Gier. "Clay mineralogy and geochemistry of early Jurassic sedimentary rocks from the Moezian Platform, northern Bulgaria." Clay Minerals 37, no. 3 (September 2002): 413–28. http://dx.doi.org/10.1180/0009855023730053.
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AbstractClay minerals in early Jurassic sequences of shales, siltstones and sandstones deposited in non-marine, transitional and shallow marine environments have been examined by X-ray diffraction, electron microscopy and chemical analysis to study the relationship between clay minerals, their environment of deposition and subsequent diagenetic modifications.The inherited clay mineral composition of the fine-grained sediments reflects the influence of climate, relief, source rocks and depositional processes. Inhomogeneous clay mineral assemblages, comprising abundant kaolinite and varying proportions of illite, I-S, chlorite and vermiculite, characterize fine-grained sediments from the non-marine and transitional environments. In shallow marine depositional environments clay mineral assemblages are more uniform, dominated by illite+I-S with minor kaolinite and chlorite.The principal diagenetic process affecting fine-grained sedimentary rocks is the smectite–illite transformation. In sandstones, the authigenic formation of kaolinite, chlorite and illite appears to have been primarily determined by the environment of deposition.
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Colgan, Patrick M., Christopher A. Vanderlip, and Katelynn N. Braunschneider. "Athens Subepisode (Wisconsin Episode) non-glacial and older glacial sediments in the subsurface of southwestern Michigan, USA." Quaternary Research 84, no. 3 (November 2015): 382–97. http://dx.doi.org/10.1016/j.yqres.2015.09.006.
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We describe the first complete sediment core to bedrock in southwestern Michigan of a radiocarbon defined sequence of Michigan Subepisode (Marine Oxygen Isotope Stage [MIS] 2) glacial sediments, Athens Subepisode (MIS 3) non-glacial sediments, and two older tills using sedimentological, lithological, and radiocarbon analyses. Organics from Athens Subepisode lacustrine and palustrine sediments yield radiocarbon ages of 41,920–42,950 and 43,630–45,340, and > 43,500 14C yr BP. We propose the name Port Sheldon Formation for these organic-bearing sediments. We interpret the underlying diamictons as two basal tills separated by glaciolacustrine fines. The youngest till (Hemlock Crossing till) lying below the Port Sheldon Formation is a dark gray, gravel-poor clay loam to loam with a mean kaolinite–illite ratio of 0.98 ± 0.04. The oldest till (Glenn Shores till) is a dark grayish brown, gravel-rich, clay loam to sandy loam with mean kaolinite–illite ratio of 1.22 ± 0.08. About 130 water-well records demonstrate that organic sediments and underlying diamictons are common in the subsurface of Ottawa County. These tills are likely Illinois Episode (MIS 6) or older, but an Ontario Subepisode (MIS 4) age cannot be ruled out. Deep bedrock basins in Lower Michigan provide an untapped archive of pre-Michigan Subepisode history.
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Newell, Silvia E., Kaitlyn R. Pritchard, Sarah Q. Foster, and Robinson W. Fulweiler. "Molecular evidence for sediment nitrogen fixation in a temperate New England estuary." PeerJ 4 (January 25, 2016): e1615. http://dx.doi.org/10.7717/peerj.1615.
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Primary production in coastal waters is generally nitrogen (N) limited with denitrification outpacing nitrogen fixation (N2-fixation). However, recent work suggests that we have potentially underestimated the importance of heterotrophic sediment N2-fixation in marine ecosystems. We used clone libraries to examine transcript diversity ofnifH(a gene associated with N2-fixation) in sediments at three sites in a temperate New England estuary (Waquoit Bay, Massachusetts, USA) and compared our results to net sediment N2fluxes previously measured at these sites. We observednifHexpression at all sites, including a site heavily impacted by anthropogenic N. At this N impacted site, we also observed mean net sediment N2-fixation, linking the geochemical rate measurement withnifHexpression. This same site also had the lowest diversity (non-parametric Shannon = 2.75). At the two other sites, we also detectednifHtranscripts, however, the mean N2flux indicated net denitrification. These results suggest that N2-fixation and denitrification co-occur in these sediments. Of the unique sequences in this study, 67% were most closely related to uncultured bacteria from various marine environments, 17% to Cluster III, 15% to Cluster I, and only 1% to Cluster II. These data add to the growing body of literature that sediment heterotrophic N2-fixation, even under high inorganic nitrogen concentrations, may be an important yet overlooked source of N in coastal systems.
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Ilegieuno, O. A., E. J. Ighodaro, and R. O. Sunny. "Sedimentology and Paleogeographic Synthesis of Cretaceous Sediments in Auchi Area of Anambra Basin." Journal of Applied Sciences and Environmental Management 24, no. 5 (June 24, 2020): 943–74. http://dx.doi.org/10.4314/jasem.v24i5.32.
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The sedimentary rock in the Auchi area of Edo State constitutes part of the Upper Cretaceous Deposits of the Anambra Basin, which has its depocentre in Eastern Nigeria. Lithostratigraphic and Sedimentological studies carried out on twenty eight (28) selected samples from a section of a road–cut show that the sediments range from fine through medium to coarse grained. Sorting is poor to moderate. Grain size analysis shows that the sediments are strongly fine skewed and they exhibit mesokurtic to platykurtic kurtosis. These coupled with the various colours observed in the sediment, ranging from whitish sand through yellowish brown, pink and reddish brown possibly indicate a non–marine environment and a fluviatile to deltaic environment of sedimentation is suggested. The sediments might have been transported in a fairly high energy medium and deposited under a slightly fluctuating velocity.
Keywords: Sedimentology, Cretaceous, Paleogeography, Grain size, Anambra Basin
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Jeng, Dong-Sheng. "Effects of Wave Non-Linearity on Residual Pore Pressures in Marine Sediments." Open Civil Engineering Journal 2, no. 1 (July 24, 2008): 63–74. http://dx.doi.org/10.2174/1874149500802010063.
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Sayles, F. L. "CaCO3 solubility in marine sediments: Evidence for equilibrium and non-equilibrium behavior." Geochimica et Cosmochimica Acta 49, no. 3 (March 1985): 877–88. http://dx.doi.org/10.1016/0016-7037(85)90180-2.
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Campbell, James A., Mark T. Mitchell, Michael J. Ryan, and Jason S. Anderson. "A new elasmosaurid (Sauropterygia: Plesiosauria) from the non-marine to paralic Dinosaur Park Formation of southern Alberta, Canada." PeerJ 9 (February 11, 2021): e10720. http://dx.doi.org/10.7717/peerj.10720.
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Elasmosaurid plesiosaurian remains have been documented from non-marine to paralic (fluvial to estuarine) sediments of the upper Campanian Dinosaur Park Formation (DPF) of southern Alberta since 1898. Despite this long collection history, this material has received relatively little research attention, largely due to the highly fragmentary nature of most recovered specimens. However, this assemblage is significant, as it constitutes a rare occurrence of plesiosaurian remains in a non-marine depositional environment. This study reports on a recently collected and prepared specimen, which represents the most complete elasmosaurid yet collected from the DPF. This specimen preserves the trunk region, the base of the neck and tail, a partial fore and hind limb, and tooth, and is sufficiently complete to be assigned as the holotype of a new genus and species. This new taxon is diagnosed by a distinctive character state combination including a boomerang-shaped clavicular arch with acute anterior process, convex anterolateral margin, deeply embayed posterior margin, and pronounced ventral keel, together with the presence of 22 dorsal vertebrae, and the anterior dorsal centra bearing a ventral notch. The DPF plesiosaurian fossils were recovered from both estuarine/bay and fluvial palaeochannel sediments. The holotype skeleton represents an osteologically mature individual with an estimated body length of around 5 m, although the largest referred DPF elasmosaurid might have been closer to 7 m, which is considerably larger than other plesiosaurians reported from non-marine deposits. This suggests small-body lengths relative to typical elasmosaurids from marine settings, but is consistent with other plesiosaurians recovered from non-marine sediments. The identification of a distinct elasmosaurid taxon in the DPF might be evidence of niche-partitioning among the predominantly oceanic members of the ubiquitous plesiosaurian clade.
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Zalat, Abdelfattah Z. "A new record of non-marine diatoms from early Miocene sediments in the northern part of the Western Desert, Egypt." Neues Jahrbuch für Geologie und Paläontologie - Monatshefte 1996, no. 1 (February 1, 1996): 31–42. http://dx.doi.org/10.1127/njgpm/1996/1996/31.
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Srivastava, S. C., Anand-Prakash, and Trilochan Singh. "Permian palynofossils from the eastern Himalaya and their genetic relationship." Journal of Palaeosciences 36 (December 31, 1987): 326–38. http://dx.doi.org/10.54991/jop.1987.1591.
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Palynofossils from the Permian sediments of the eastern Himalaya have been critically revised with reference to the marine invertebrate fossils contained at various levels. The Pebble Slate Member of the Rangit Formation having sporadic presence of Eurydesma (Biozone 1) has not yielded palynofossils but the younger Rilu Member has yielded a radial monosaccate rich assemblage (Biozone 2). The association of Leiosphaeridia in this assemblage in Barpathar area characteristically indicates marine influence. Biozone 3 characterised by Callumispora + Parasaccites association is present in marine Garu Formation in Siang and Subansiri, non-marine Bhareli Formation in Kameng and Lower Coal Measures in Darjeeling District. Scheuringipollenites rich Biozone 4 is characteristically associated with the marine invertebrates in Siang District (Garu Formation) only; elsewhere it occurs independently. Biozones 5 and 6 are characterized by the abundance of striate-disaccate pollen grains, the latter having Indospora, Thymospora and Crescentipollenites and represent Upper Barakar and Raniganj palynofloras, respectively.
The Permian sediments in eastern Himalaya are in lithological contrast with the intracratonic continental sediments of the Peninsula but their floristic resemblances are close. Biozones 1 and 2 are comparable to Talchir palynoflora which is related to glacio-marine model of sedimentation. During the deposition of sediments containing Biozone 3, comparable to Karharbari palynoflora, the marine environment seems to have existed continuously from Siang to eastern Kameng but westwards certain areas were under fresh water environment. Similarly, Biozone 4 is associated with marine fossils in Siang only but elsewhere it is typically associated with fluvial sediments. Thus an eastward regression of the sea is plausible during Karharbari and Lower Barakar times. During the younger palynofloras having Upper Barakar (Biozone 5) and Raniganj (Biozone 6) affinities the conditions of deposition appear to be exclusively fluvial in nature. It is clearly indicated that a larger segment of sedimentation in these marginal basins of eastern Himalayas has continued under marine environment while in peninsular India the intracratonic depositional basins were under fluvial environment during the same time span.
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Wafula, Matthews, Agnes W. Muthumbi, Virginia Wangondu, Charles Kihia, and Julius Okondo. "Nematodes as bio-indicators of physical disturbance of marine sediments following polychaete bait harvesting." Western Indian Ocean Journal of Marine Science 19, no. 2 (April 2, 2021): 117–30. http://dx.doi.org/10.4314/wiojms.v19i2.9.
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Sediment disturbance in marine environments is caused by activities including polychaete bait harvesting, trawling, dredging, sediment erosion and treading. These activities affect the benthic communities by changing the densities, community assemblage and diversity. The aim of this study was to evaluate the potential of nematodes as indicators of sediments disturbance following polychaete bait harvesting. The study was conducted in three sites experiencing different bait harvesting intensities in Mida Creek, Kenya. Sediment samples were collected from the mudflats during low tide, preserved in 5% formalin and transported to the laboratory for processing and identification of nematodes. The highly disturbed site recorded the lowest nematode genus richness while the less disturbed sites had the highest. Overall, the most abundant nematode genera in the non-disturbed (Dabaso) and less disturbed sites (Kirepwe) were selective deposit feeders (Spirinia and Terschellingia), while most disturbed sites (e.g. Mayonda) had predators/omnivores (Pheronus, Aporcelaimellus) and selected members of the genus Spirinia. The disturbed site was characterised by low nematode diversity (H’) and low dominance (D) while the non-disturbed and less disturbed sites had higher diversity and dominance. Clearly, nematode community assemblage, diversity and feeding guilds changed following disturbance to a low diversity that favoured higher proportions of predator/omnivore taxa.
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Ružičić, Stanko, Goran Durn, Ivan Sondi, Lucija Mihaljević, and Maja Ivanić. "The relationship between the geochemical and mineralogical characteristics of Calcocambisol, colluvium and recent marine lake sediment of the narrow seashore intertidal zone: a case study from the Veliko Jezero (Mljet Island, Croatia)." Geologia Croatica 74, no. 2 (June 30, 2021): 153–62. http://dx.doi.org/10.4154/gc.2021.10.
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This study investigates the mineral composition, particle size distribution and geochemical characteristics of Calcocambisol, colluvium and recent marine lake sediment in a narrow intertidal seashore zone of the Veliko Jezero on the Island of Mljet (Croatia). The obtained results show that the fractions of Calcocambisol/colluvium less than 2 mm and 2 μm display similar particle size distribution (PSD) curves compared to marine lake sediments containing larger particles in these fractions. The smallest fractions of the investigated materials that are less than 1 μm show identical PSD curves. The bulk and clay mineral composition of the marine lake sediment show that the non-carbonate fraction is derived from weathering of the surrounding soils and colluvium containing quartz, feldspars and phyllosilicates (illitic material, kaolinites, chlorite, and a mixedlayer clay mineral, MLCM), as well as the authigenic formation of early-diagenetic pyrite, while one part is related to the yield of material by aeolian deposition (amphibole). The observed difference between the phyllosilicate mineral phases in the clay fraction of the Calcocambisol/colluvium and the carbonate-free clay fraction of the marine lake sediment is related to 1) the presence of chlorite in the marine lake sediment and 2) the higher content of MLCM in the Calcocambisol/colluvium. The chlorite in the marine lake sediment was inherited from the Calcocambisol/colluvium as a result of soil erosion prior to its complete destabilization in the soil. High Chemical Index of Alteration (CIA) values in the Calcocambisol and colluvium clearly indicate their intense weathering. Based on the Sm/Nd and Ti/Al ratios, it can be concluded that the aluminosilicates in the Calcocambisol, colluvium and marine lake sediment are of the same provenance. The distribution of each analysed element among the sequential fractions is very similar in both the Calcocambisol and colluvium. The highest concentrations for most of trace elements in the Calcocambisol, colluvium and marine lake sediment was determined in their residual fraction. Mn, Co and Pb show a different partitioning between the Calcocambisol/colluvium and marine lake sediment, respectively.
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Ilyina, V. I. "Subdivision and correlation of the marine and non-marine Jurassic sediments in Siberia based on palynological evidence." Review of Palaeobotany and Palynology 48, no. 4 (September 1986): 357–64. http://dx.doi.org/10.1016/0034-6667(86)90073-4.
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Thusu, B., and J. O. Vigran. "Middle – Late Jurassic (Late Bathonian – Tithonian) Palynomorphs." Journal of Micropalaeontology 4, no. 1 (March 1, 1985): 113–29. http://dx.doi.org/10.1144/jm.4.1.113.
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Abstract. INTRODUCTIONJurassic palynomorph assemblages have been recovered in numerous wells in northeast Libya. Jurassic rocks reflect changing sedimentary environments which have greatly influenced the composition of the palynological assemblages.In the northernmost area, Jurassic sediments unconformably overlie the Palaeozoic or Triassic and show a mixed marine and continental influence. In the northeastern part of the area thicker and deeper water marine sediments are known, while shallow marine sediments overlie the platform facies immediately to the south. Pollen and miospores are fairly well preserved and are dominant in most samples. Dinoflagellate cysts are richly represented especially in the deposits of the north and northeast. Most samples contain abundant variably sorted cuticular debris and structured wood fragments. This significant influx of terrestrial debris together with the associated palynomorph assemblages indicate deposition in a shallow marine environment in close proximity to the shoreline for most of the Jurassic deposits in the northern area.In the central and southern region, sandstone, silt stone and red shale deposited in non-marine fluvial to lacustrine or lagoonal environment, unconformably overlie the metamorphic or igneous Precambrian Basement. These sediments show a general lack of well preserved palynomorphs. Miospores, though present are generally long ranging and terrestially derived detrital kerogen dominate the assemblages.MICROFLORAL SUCCESSIONMiospore assemblages present in most of the samples investigated are dominated by small gymnosperm pollen. Classopollis spp., Exesipollenites spp., Sphaeripollenites spp., and nonaperturate pollen assigned to Araucariacites spp. Saccate pollen assigned to Concentrisporites spp., Perinopollenites spp., Callialasporites spp., and Inaperturopollenites spp., are often common . . .
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Taylor, Kevin G. "Non-marine oolitic ironstones in the Lower Cretaceous Wealden sediments of southeast England." Geological Magazine 129, no. 3 (May 1992): 349–58. http://dx.doi.org/10.1017/s0016756800019282.
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AbstractOolitic ironstones are described from the early Cretaceous non-marine Wealden sediments of southeast England. The recognition of non-marine oolitic ironstones in the geological record is rare and, therefore, warrants further study. The oolitic ironstones described take two forms, named here type-I and type-2 ironstones.Type-1 ironstones contain pisoids and ooids of berthierine together with sandstone fragments and detrital quartz grains. The pisoids (up to 0.5 cm in size) vary from subspherical to highly irregular. The smaller ooids (up to 1 mm in size) are generally ellipsoidal but strongly asymmetrical forms are also present. The form of these pisoids and ooids suggest that mechanical accretion was not the dominant mechanism controlling their formation. It is proposed that this ironstone type formed from the reworking and redeposition of local soil material.Type-2 ironstones, of which only one unequivocal example has been studied, is composed of iron oxide ooids set in a detrital matrix. The ooids are most commonly regularly ellipsoidal and exhibit a decrease in iron at their centres. It is proposed here that the ooids suffered post-depositional iron depletion at their centres, in a similar fashion to that proposed for the recent Lake Chad oolites. There is no unequivocal evidence as to the origin of the ooids.This study is important in that it shows that different ironstones can be formed by different processes essentially within the same environment. Comparison of non-marine oolitic ironstones with the better-developed marine examples should prove a valuable exercise.
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Abrahamsen, Niels. "Paleomagnetism of Quaternary sediments from Anholt, Denmark: Onset of the Blake Event and Eem." Bulletin of the Geological Society of Denmark 42 (October 31, 1995): 96–104. http://dx.doi.org/10.37570/bgsd-1995-42-09.
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Trie c. 70 m non-marine Weichselian sands and clays from two consecutive borings, Anholt II and III, show normal polarity and inclinations somewhat shallower (c. 115°) than the axial dipole field value, which may be explained by a moderate compression of the sediment. Most of the marine shallow water silty clays of the Saalian (isotope stage 6) and Eemian (isotope substage 5e) sections (74-81 m) also show normal inclinations, except for two samples at the very top part of the recovered Eemian stage, which are distinctly reversely magnetized. The reversed section of the Pleistocene sediments (in Anholt III) is interpreted to belong to the earliest part of the short reverse geomagnetic Blake event. Correlation via biostratigraphy and oxygen isotopes provides an estimate for the onset of the Blake reversal at about 123 ka which, together with the termination date of 117 ka from Lac de Bouchet, possibly suggest an age of about 123-117 for the Blake reversal.
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Ognjanova-Rumenova, Nadja, and Radovan Pipík. "Stratigraphic and taxonomic significance of siliceous microfossils collected from the Turiec Basin, Western Carpathians (Slovakia)." Acta Botanica Croatica 74, no. 2 (October 1, 2015): 345–61. http://dx.doi.org/10.1515/botcro-2015-0023.
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Abstract This study provides the first biostratigraphic data of siliceous microfossils from Turiec Basin, Slovakia. The fossil diatom flora consists of 42 species and varieties, belonged to 22 genera. The diatom assemblage studied from the Turiec Basin bears a strong resemblance to assemblages from non-marine diatomaceous sediment of Miocene age from Rüdenschwinden, a village of the eastern slope of the Hohe Rhön (Central Germany), non-marine sediments of the early Late Miocene from the village of Szilagy (South Hungary), as well as from Bes Konak Basin, Turkey. The investigated profile is generally dominated by Alveolophora jouseana. The similarities and differences within the taxonomy of certain species belonging to the genera Aulacoseira, Alveolophora and Miosira are discussed. The accompanying species are species of the genus Fragilaria Lyngbye sensu lato from class Fragilariophyceae. The most interesting taxa belong to the genus Staurosirella - S. grunowii, S. leptostauron, S. martyi. Among them are two very unusual taxa identified only to genus. Ecological data for the diatom taxa and the diatom frustules/ chrysophycean stomatocysts ratio are used in an attempt to reconstruct in detail the palaeoecological conditions at the time of sediment deposition.
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Taylor, K. G. "Berthierine from the non-marine Wealden (Early Cretaceous) sediments of south-east England." Clay Minerals 25, no. 3 (September 1990): 391–99. http://dx.doi.org/10.1180/claymin.1990.025.3.13.
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AbstractA thin (15–20 cm) Fe-rich intraformational conglomerate in the fresh- to brackish-water Early Cretaceous succession of south-east England contains pisoids and pseudo-ooids of a green clay mineral which has been identified as berthierine. The pisoids (up to 0·5 cm in size) are concentrically laminated, have complex structure, and are frequently nucleated around a sandstone fragment. They show evidence of weathering due to a change in their environment after formation. The ooids have well to moderately well developed concentric lamination, are very often multi-nucleated and do not always completely cover the nucleus. They suggest formation as a result of mineral precipitation as opposed to agitation and accretion. The climate and environment during the Wealden were suited to the formation of Fe-rich soils and it is likely that the pisoids and ooids were originally composed of iron oxyhydroxide and kaolinite, having formed in soil in the Weald Basin. They were then eroded and deposited in the base of a large scour structure as part of the conglomerate. On burial, and the attainment of low Eh conditions, berthierine formed by diagenetic transformation of the pre-existing minerals.