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Petroleum Geological Survey
Published in Muhammad Abdul Quddus, Petroleum Science and Technology, 2021
Chemical processes are responsible for the creation of certain types of surface structure in the rock by the precipitation of minerals on top of each other. The precipitation process also brings about stratification. Biological processes or biogenic processes are initiated by living organisms. The processes generate tracks and trails in the rock, known as ‘bioturbation sedimentary structure’. Bioturbation is the reworking of sediments by living animals and plant organisms which disrupts and alters the original structure. Animal habits and activities including taking food and passing feces also affect the sediment structure.
Index, Compressibility, and Strength of Marine Sediments
Published in Ronald C. Chaney, Marine Geology and Geotechnology of the South China Sea and Taiwan Strait, 2020
Bioturbation is defined as a reworking of soils and sediments by plants and animals. These include burrowing ingestion and defecation of the sediment grains. Richards (1981) stated that benthic biologists believe that every grain of soil in the upper layers of the seabed has passed through the guts of some marine animals, which deposits a mucus membrane on particles.
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Published in Gunnar Kullenberg, Pollutant Transfer and Transport in the Sea, 2018
Egbert K. Duursma, Maarten Smies
With Db having values of 10-6 to 10-8 cm2 s-1, L being 3 to 10 cm and W being in the order of 10-8 cm s-1, G takes on values varying from 0.1 to 10. At the former value of G, bioturbation hardly plays a role in downward transport of sediment while at the latter value, the deposited sediment grains become uniformly mixed through the zone of bioturbation before being transported below the layer of bioturbative activity by sedimentation.
An integral approach to simulate three-dimensional flow in and around a ventilated U-shaped chironomid dwelled burrow
Published in Journal of Ecohydraulics, 2021
Vahid Sobhi Gollo, Tabea Broecker, Jörg Lewandowski, Gunnar Nützmann, Reinhard Hinkelmann
Charles Darwin realized the relevance of biological reworking of soils and sediments (Darwin 1881; Meysman et al. 2006). Nowadays bioturbation is defined as “all transport processes carried out by animals that directly or indirectly affect sediment matrices. These processes include both particle reworking and burrow ventilation” (Kristensen et al. 2012). Bioturbators are considered ecosystem engineers (Meysman et al. 2006; Kristensen et al. 2012). Some bioturbators live in marine and freshwater sediment where they build open-ended or blind-ended burrows and actively pump overlying water through their burrows (ventilation) to supply themselves with oxygen and/or food. Burrow ventilation causes advective and diffusive exchange of solutes between overlying water, water in the burrows and sediment pore water called bioirrigation (Kristensen et al. 2012).
Sediment critical shear stress and geotechnical properties along the modern Yellow River Delta, China
Published in Marine Georesources & Geotechnology, 2018
Xiao-Lei Liu, Jie-Wen Zheng, Hong Zhang, Shao-Tong Zhang, Bao-Hua Liu, Hong-Xian Shan, Yong-Gang Jia
The field observation showed that abundant benthic organisms spread over the middle tidal flat compared to the high and low tidal flats (Figure 5, Jia et al. 2011). Compared to the effect of sediment physical properties to critical shear stress, biological process can be considered as an important factor for the heterogeneous distribution of critical shear stress in middle tidal flat. Benthos community structure and its benthic effect can play a significant role in the formation, development, and stability of the sedimentary characteristics of estuarine tidal flat (Li et al., 2017). Bioturbation and faecal material can change sediments through physics and chemicals and then affect the topographic features and the chemical cementation between sediment particles (Yang et al. 2010). In the middle tidal flats in different sedimentary areas of the modern Yellow River Delta, benthos of different type and density play a different role to the fine sediment with different particle composition, then affect sediment critical shear stress in different degrees and mechanisms resulting in the heterogenetic distribution of critical shear stress on different spatial scales.
Enhanced removal of sediment-associated total petroleum hydrocarbons under bioturbation by polychaete perinereis aibuhitensis
Published in Journal of Environmental Science and Health, Part A, 2019
Yifan Tong, Jingyi Li, Qianhui Cheng, Caihong Gao, Yaqi Yang, Shengyan Tian
Many kinds of benthic fauna live in coastal sediments. The life activities of benthos, including burrowing, construction and maintenance of galleries, as well as ingestion and defecation, actively rework the sediment particles, such as displacement and mixing of particles, couple with burrow ventilation, which occurs when animals flush their burrows with overlying water for respiratory and feeding purposes[12]. The benthic organisms induced sediment reworking as well as burrow ventilation is defined as bioturbation[12], which is one of the major processes influencing the physical, chemical and biological properties of aquatic sediments, and inducing enhancement of organic matter mineralization in most cases[13–20]. Bioturbation processes enhance transport of oxygen and other electron acceptors into otherwise reduced environments may affect the mineralization rate and degradation pathway as well as the composition of the microbial communities[16,21]. Some sediment-dwelling polychaetes, for example, Nereis diversicolor, were found to enhance microbial degradation of buried petroleum due to favouring the development of hydrocarbon degrading bacteria in oil polluted sediment[22]. Moreover, some polychaetes could metabolize petroleum hydrocarbons[23] and polycyclic aromatic hydrocarbons (PAHs) in sediment[24–27]. Hence, bioturbation by polychaetes is potentially to remediate petroleum contaminated sediment.