Algal Blooms and "Marine Snow": Mechanisms That Enhance Preservation of Organic Carbon in Ancient Fine-Grained Sediments

Haynesville and Bossier mudrocks: A facies and sequence stratigraphic investigation, East Texas and Louisiana, USA

“…Origin of peloids is related to flocculation of organic particles that might be equivalent to marine snow, as identified in modern deep-sea sediments and fecal pellets that settled on the seafloor (e.g., Stow, 1994;Honjo, 1997;Loucks and Ruppel, 2007;Schieber et al, 2007;Macquaker et al, 2010). This hypothesis would explain the relatively significant amount of organic matter encountered in the HVL shale.…”

“…Despite recent advances in mudrock geology (Potter et al, 1980(Potter et al, , 2005Roehl et al, 2001;Schieber, 2003;Loucks and Ruppel, 2007;Macquaker et al, 2007Macquaker et al, , 2010Hammes et al, 2011), understanding and constraining their deposition remain difficult owing to a number of parameters influencing it. Mudrocks are fine-grained deposits, commonly thought to contain silt-to clay-particle sizes (e.g., Stow, 1981;Potter et al, 2005;Loucks and Ruppel, 2007).…”

The role of event beds in the preservation of organic carbon in fine-grained sediments: Analyses of the sedimentological processes operating during deposition of the Whitby Mudstone Formation (Toarcian, Lower Jurassic) preserved in northeast England

“…The presence of these fabrics in the Grey Shale Member is not particularly remarkable, given its stratigraphic position immediately overlying the Cleveland Ironstone Formation, where similar fabrics are well-documented (e.g., Greensmith et al, 1980;Wright, 1992, 1996;Taylor, 1996, 1997;Wignall et al, 2005;Macquaker et al, 2010b;Ghadeer and Macquaker, 2011). The presence of these structures in the Mulgrave Shale Member, however, is more unexpected, as this interval has been interpreted (e.g., Wright, 1996, 2000;Saelen et al, 1996Saelen et al, , 2000Jenkyns and Clayton, 1997;Kemp et al, 2005;Wignall et al, 2005;Powell, 2010) as having been deposited in a low-energy environment, where the main mode of sediment delivery was suspension settling from buoyant plumes.…”

“…5C, D). This organo-minerallic fabric has recently been interpreted to be the depositional product of marine snow aggregates that formed in the water column (see Macquaker et al, 2010b). In modern fully marine settings, most of the fine-grained material that is delivered to the sea-floor is bundled into aggregate grains that were produced in the water column by a combination of random grain collisions and the effects of filter feeding organisms (e.g., Kranck and Milligan, 1980;Kranck, 1984;McCave, 2005).…”

Mechanical Properties of Longmaxi Black Organic-Rich Shale Samples from South China under Uniaxial and Triaxial Compression States

“…Depositional processes, productivity, and bottom water redox conditions have a profound control on the basin-wide distribution of lithofacies as well as the amount and quality of organic matter [25][26][27][28][29][30][31][32][33]. The Sichuan Basin developed on the Precambrian metamorphic basement of the upper Yangtze craton [34].…”