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Journal Article
Journal: PALAIOS
Published: 01 July 2017
PALAIOS (2017) 32 (7): 462-489.
...LIJING LIU; YASHENG WU; HONGXIA JIANG; NAIQIN WU; LIANQI JIA Abstract:The stratigraphic and facies distribution of 20 calcimicrobial genera (including calcified cyanobacteria and associated problematic calcified microfossils) are reported for the entire Ordovician succession in the Tarim Basin...
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Journal Article
Published: 06 March 2017
Journal of Paleontology (2017) 91 (3): 369-392.
...Min Shi; Qing-Lai Feng; Maliha Zareen Khan; Stanley Awramik; Shi-Xing Zhu AbstractCherts and silicified dolostones of the ca. 1600 Ma Dahongyu Formation (uppermost Changcheng Group) from North China contain well-preserved microfossils. Cyanobacteria filaments and coccoids...
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Journal Article
Journal: Geology
Published: 01 December 2016
Geology (2016) 44 (12): 1007-1010.
... (fungi, cyanobacteria) are more representative of early soil-forming communities. Liverwort and lichen soils are thin, and their depth and complexity are constrained by the size and growth form of the dominant plants or lichens. They are aggregated and stabilized by cyanobacteria, mycorrhizal...
Journal Article
Journal: Geology
Published: 01 August 2016
Geology (2016) 44 (8): 615-618.
FIGURES
Journal Article
Published: 01 June 2016
Journal of Sedimentary Research (2016) 86 (6): 629-636.
... descriptions and classifications for tropical tidal-flat environments have focused predominantly on morphological observations. This is exemplified by flat and biscuit-shaped mats, where the mat morphotypes are postulated to reflect different Cyanobacteria communities as the main mat-building taxa. To compare...
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Journal Article
Journal: PALAIOS
Published: 01 November 2015
PALAIOS (2015) 30 (11): 792-801.
... the processes which occurred within a microbial ecosystem as a whole over an extended time period. Microbial mats are complex benthic communities organized as millimetric multi-layered microecosystems frequently dominated by cyanobacteria. These communities have a distinct vertical structure ( Cohen 1989...
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Journal Article
Journal: Geology
Published: 01 October 2015
Geology (2015) 43 (10): 855-858.
... dense mazes of filamentous fossils, which were interpreted as algae or cyanobacteria, thus pointing to a shallow-marine subtidal or intertidal environment. The data presented here reveal that these filaments represent remains of colorless, vacuolated sulfide-oxidizing bacteria. This interpretation...
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Journal Article
Journal: Geology
Published: 01 October 2015
Geology (2015) 43 (10): 887-890.
... occurred locally as much as 2.8 b.y. ago, creating O2 oases, or initiated just prior to the GOE. The biogeochemical dynamics of possible O2 oases have been poorly constrained due to the absence of modern analogs. However, cyanobacteria in microbial mats in a perennially anoxic region of Lake Fryxell...
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Journal Article
Published: 05 August 2015
Geological Magazine (2015) 152 (6): 1145-1148.
... layers at c. 551±4Ma. Within this strata interval, other characteristic Ediacaran microorganisms co-occur such as cyanobacteria, vendotaenids, microalgae, Ceratophyton, Valkyria and macroscopic annelidan Sabellidites. The recent contributions of organic sclerites in revealing...
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Journal Article
Published: 01 May 2015
Journal of the Geological Society (2015) 172 (3): 390-406.
... utilization by cyanobacteria or sulphur bacteria leading to negative kerogen δ15N values. During Stage 3, dissolved oxygen and sulphate concentrations were significantly increased, and thus the oxidized surface water and the redox transition zone overlying a euxinic bottom water may have been expanded...
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Journal Article
Journal: Elements
Published: 01 February 2015
Elements (2015) 11 (1): 14-15.
Journal Article
Journal: Geology
Published: 01 August 2014
Geology (2014) 42 (8): 671-674.
..., and may in the past have been, fertilized by atmospheric dust, promoting the fixation of atmospheric N2 by cyanobacteria. These cyanobacteria provided a source of nitrogen to the rest of the community in this nutrient-poor environment. The fixation of N has imparted a characteristic δ15N signal and has...
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Series: GSA Reviews in Engineering Geology
Published: 01 January 2014
DOI: 10.1130/2014.4122(16)
EISBN: 9780813758220
... of the soil, physically entwining soil particles and aggregates ( Fletcher and Martin, 1948 ; Belnap and Gardner, 1993 ). Various fungi and cyanobacteria secrete extracellular polysaccharide compounds that glue soil particles together ( Tisdall and Oades, 1982 ; de Cano et al., 1997 ). Soil aggregates...
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Journal Article
Journal: PALAIOS
Published: 01 January 2014
PALAIOS (2014) 29 (1): 27-37.
... of sponges or microstromatolites) without reworking. The upward growth patterns of microstromatolites and Girvanella encrusting other surfaces suggest that they were most likely formed by photosynthetic cyanobacteria ( Riding 1991 , 2000 ). The occurrences of microstromatolites in growth positions...
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Journal Article
Published: 01 July 2013
Mineralogical Magazine (2013) 77 (5): 1352-1367.
Journal Article
Journal: PALAIOS
Published: 01 July 2013
PALAIOS (2013) 28 (7): 453-470.
... filamentous or coccoidal cyanobacteria give way to a series of more robust forms that show increasing assemblage diversity with decreasing evidence of subaerial exposure. Distinct fabric elements are associated with each microbial assemblage, and aspects of these petrofabrics are recognizably preserved within...
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Journal Article
Published: 01 March 2013
Journal of the Geological Society (2013) 170 (2): 341-352.
... increase in kaolinite content reflects a short-lived change to humid conditions. The δ15N values close to 0‰ above the PEB suggest a bloom of N2-fixing cyanobacteria. Increased bacterial activity may be either the cause or the result of the anoxia locally associated with the PETM. For the calcareous...
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Journal Article
Journal: PALAIOS
Published: 01 May 2012
PALAIOS (2012) 27 (5): 304-316.
... using Raman spectroscopy, and elemental mapping by electron microbeam techniques. These fossils have been interpreted as dissociated algal fragments, and accordingly, were compared to known algal fossils: Yuknessia simplex (green alga; Spence Shale), Marpolia spissa (cyanobacteria; Burgess Shale...
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Journal Article
Journal: PALAIOS
Published: 01 April 2012
PALAIOS (2012) 27 (4): 206-219.
... orientations. D) Orientation score 5: No recognizable orientation. The notion that photosynthetic filamentous microbes (e.g., cyanobacteria) orient toward the light is a basic tenet of microbialite studies ( Monty, 1967 ; Gebelein, 1969 ; Golubic, 1973 ; Walter et al., 1972 , 1976 ; Golubic and Focke...
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Journal Article
Journal: Palynology
Published: 01 December 2011
Palynology (2011) 35 (2): 155-178.
... that the organic residue prepared for pollen analysis yields other organic-walled microfossils that can be used to provide additional and independent palaeoenvironmental information. These non-pollen palynomorphs (NPP) include microscopic remains of algae, cyanobacteria, fungi, insects, other invertebrates...
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