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Chuaria

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Journal Article
Journal: Geology
Published: 01 January 2017
Geology (2017) 45 (1): 75–78.
... documented. To address this knowledge gap, we investigated Chuaria and associated carbonaceous compression fossils from the Tonian Liulaobei Formation in North China. These fossils have been variously interpreted as unicellular or multicellular organisms. Our analysis using backscattered-electron scanning...
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First thumbnail for: Electron microscopy reveals evidence for simple mu...
Second thumbnail for: Electron microscopy reveals evidence for simple mu...
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Journal Article
Published: 01 May 1990
Journal of Paleontology (1990) 64 (3): 488.
Series: GSA Microform Publications
Publisher: Geological Society of America,
Published: 01 January 1990
DOI: 10.1130/micro20-p168
EISBN: 9780813759203
... Abstract This is the first supplement to the Annotated Bibliography of the World Literature on the Grand Canyon Type Fossil Chuaria circularis Walcott, 1899. The reader is referred to extensive introductory material that appeared in Vol. 3 of the Grand Canyon bibliography (Spamer, 1988, Geol...
Series: GSA Microform Publications
Publisher: Geological Society of America, Inc.
Published: 01 January 1983
DOI: 10.1130/micro17-p94
EISBN: 9780813759173
... Abstract This annotated bibliography is a guide to the literature on Chuaria Walcott, 1899, currently understood to be a nmnospecific genus represented by C. circularis Walcott, to which a number of other taxa have been referred in taxonomic synonymy. Because of the taxonomic complications...
Journal Article
Published: 01 November 1973
Journal of Paleontology (1973) 47 (6): 1108–1112.
Series: SEPM Special Publication
Publisher: SEPM (Society for Sedimentary Geology)
Published: 01 January 2007
DOI: 10.2110/pec.07.86.0151
EISBN: 9781565762947
Series: SEPM Special Publication
Publisher: SEPM (Society for Sedimentary Geology)
Published: 01 January 2007
DOI: 10.2110/pec.07.86.0167
EISBN: 9781565762947
Image
Acritarchs (large). (a, b) Chuaria sp. (c) Large leiosphaerid encrusted with pyrite framboids. (d) Cell aggregate mass. (e–h) Large, densely packed cell aggregates. (i) Cluster of sphaeromorphic acritarchs. (j–l) Compact, regular spheroid clusters assigned to Symplassosphaeridium. (m, n) Irregular aggregates of loosely-bound spheroids assigned to Synsphaeridium. Scale bars represent 200 µm (a–i); 100 µm (j–n). (a, b, i) 72.20 m M52-Hail-04-004 core; (c–h) 72.70 m M52-Hail-04-004 core; (j–n) 7.53 m Saarijärvi M52/3533/84/313 core. All specimen numbers have the prefix PMU 38: (a) 158/7; (b) 157/8; (c) 159/7; (d) 161/13; (e) 156/4; (f) 156/5; (g) 160/9; (h) 160/10; (i) 162/9; (j) 165/1; (k) 165/2; (l) 165/3; (m) 165/4; (n) 165/5.
Published: 24 August 2021
Fig. 9. Acritarchs (large). (a, b) Chuaria sp. (c) Large leiosphaerid encrusted with pyrite framboids. (d) Cell aggregate mass. (e–h) Large, densely packed cell aggregates. (i) Cluster of sphaeromorphic acritarchs. (j–l) Compact, regular spheroid clusters assigned to Symplassosphaeridium . (m
Image
Reflected light microscopy (RLM) photographs of Chuaria and associated fossils from the Liulaobei Formation, North China. A, B: Specimen with concentric compressional folds (A) and V-shape rupture (A,B, arrows), VPIGM-4688 (Virginia Polytechnic Institute Geosciences Museum, Virginia, USA), LLB-T1–1–2, and VPIGM-4689, LLB-T9–9–1. C: Specimen with radial splits likely of taphonomic origin, VPIGM-4690, LLB-T2–4–5. D: Small specimens (<1 mm in diameter) on bedding surface, VPIGM-4691, LLB-T10–1–1. E, F: Loosely packed cells (arrowheads) enclosed within a common envelope with concentric compressional folds, VPIGM-4692, LLB-T8–16–3, and VPIGM-4693, LLB-T9–39–1, respectively.
Published: 01 January 2017
Figure 2. Reflected light microscopy (RLM) photographs of Chuaria and associated fossils from the Liulaobei Formation, North China. A, B: Specimen with concentric compressional folds (A) and V-shape rupture (A,B, arrows), VPIGM-4688 (Virginia Polytechnic Institute Geosciences Museum, Virginia
Book Chapter

Series: GSA Microform Publications
Publisher: Geological Society of America, Inc.
Published: 01 January 1983
DOI: 10.1130/micro17-p4
EISBN: 9780813759173
... part, “An annotated Bibliography of the World Literature on the Grand canyon Type Fossil Chuaria circularis Walcott, 1899, an Index Fossil for the Late Proterozoic” This bibliography was prepared as a separate publication. However, it is apparent from reading the very recent literature (see...
Journal Article
Journal: Geology
Published: 01 July 2011
Geology (2011) 39 (7): 643–646.
... focused on the microchemistry of Cambrian BST fossils, but comparative data from organic-walled microfossils were not available. To address these issues, we analyzed two organic-walled taxa from the Yangtze Gorges area of the South China block, Chuaria (an acritarch) and Vendotaenia (a ribbon-shaped...
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First thumbnail for: Taphonomic study of Ediacaran organic-walled fossi...
Second thumbnail for: Taphonomic study of Ediacaran organic-walled fossi...
Series: GSA Microform Publications
Publisher: Geological Society of America, Inc.
Published: 01 January 1983
DOI: 10.1130/micro17-p50
EISBN: 9780813759173
...-indexed to all three volumes. The opportunity is taken herein to also update entries for Chuaria circularis Walcott and for Melanocyrillium Bloeser, spp. The updated entry for C. circularis complements Part III of this volume, the annotated bibliography of the world literature on Chuaria. To maintain...
Image
Photomicrographs, backscattered electron (BSE) images, and energy dispersive X-ray spectroscopic (EDS) elemental maps of Chuaria from Sifangtan and Vendotaenia. A–D: Reflected light photomicrograph, BSE image, C, and Fe maps of two Chuaria specimens (SFT-24–1-#6, SFT-24–1-#7). Box indicates area where elemental maps were made. E–F: Transmitted light photomicrograph and BSE image of Chuaria specimen (SFT-15–2-#9) in cross section. G–I: Close-up BSE image, Fe, and S maps of box area in F. J: Reflected light photomicrograph of several entangled Vendotaenia (from Miaohe) ribbons (MH-7-#1), with box indicating area of BSE image (K). K: Box indicates area of Ca (L) and S (M) maps. N: BSE image of a Vendotaenia specimen (from Wuhe) (SBT-9-#3) in cross section; box indicates area of oxygen (O), calcium (P), carbon (Q), and sulfur (R) maps.
Published: 01 July 2011
Figure 2. Photomicrographs, backscattered electron (BSE) images, and energy dispersive X-ray spectroscopic (EDS) elemental maps of Chuaria from Sifangtan and Vendotaenia . A–D: Reflected light photomicrograph, BSE image, C, and Fe maps of two Chuaria specimens (SFT-24–1-#6, SFT-24–1-#7). Box
Journal Article
Published: 01 June 1988
Jour. Geol. Soc. India (1988) 31 (6): 584–590.
...P. K. Maithy; Rupendra Babu Abstract Macrobiota comprising body fossils and trace fossils are reported from the Semri and Kaimur Groups of the Vindhyan Supergroup exposed around Chopan. Carbonaceous compressions of Chuaria minima and Tawuia dalensis, impressions of Sekwia excentrica and moulds...
Journal Article
Journal: GSA Bulletin
Published: 01 August 1982
GSA Bulletin (1982) 93 (8): 681–699.
...DONALD P. ELSTON; EDWIN H. McKEE Abstract A structural disturbance that ended deposition of Chuaria -bearing marine shale of middle Proterozoic age in northern Arizona is recorded by strata within the Sixtymile Formation at the top of the Grand Canyon Supergroup. The disturbance involved marine...
Image
Reflected light microscopy (RLM), secondary-electron scanning electron microscopy (SE-SEM), and backscattered-electron SEM (BSE-SEM) photographs of tightly packed cell aggregates interpreted as Chuaria colonies. A: Slab with randomly distributed Chuaria and associated fossils, VPIGM-4694 (Virginia Polytechnic Institute Geosciences Museum, Virginia, USA), LLB-T2–31. B: Magnified view of one specimen shown in A, VPIGM-4694a, LLB-T2–31–3. C: VPIGM-4695, LLB-T1–18–1. Photographic modes are marked in lower left of each panel. B3–B5 and C2–C3 are series of variable-voltage BSE-SEM photographs, with accelerating voltages marked in lower right.
Published: 01 January 2017
Figure 3. Reflected light microscopy (RLM), secondary-electron scanning electron microscopy (SE-SEM), and backscattered-electron SEM (BSE-SEM) photographs of tightly packed cell aggregates interpreted as Chuaria colonies. A: Slab with randomly distributed Chuaria and associated fossils, VPIGM
Image
Photomicrographs, backscattered electron (BSE) images, and energy dispersive X-ray spectroscopic (EDS) elemental maps of three Chuaria specimens from Sixi, China. A–F: Reflected light photomicrograph, BSE image, Si, Al, Mg, and Ca maps of specimen (08-SX-DST3–3B3-#4) on bedding surface. G–L: Reflected light photomicrograph, BSE image, Si, Al, Mg, and Ca maps of specimen (08-SX-DST3–3B3-#5) on bedding surface. M: Transmitted light photomicrograph of Chuaria specimen (08-SX-DST3–3D1e-#1) in cross section perpendicular to bedding plane. Elemental maps (not shown) indicate that opaque material is Ca and P rich (labeled as phosphate). Box indicates area where Si (N), Al (O), and Mg (P) maps were made.
Published: 01 July 2011
Figure 1. Photomicrographs, backscattered electron (BSE) images, and energy dispersive X-ray spectroscopic (EDS) elemental maps of three Chuaria specimens from Sixi, China. A–F: Reflected light photomicrograph, BSE image, Si, Al, Mg, and Ca maps of specimen (08-SX-DST3–3B3-#4) on bedding
Journal Article
Published: 01 November 2019
Journal of Paleontology (2019) 93 (6): 1276–1278.
..., and their biostratigraphic implications : Precambrian Research , v. 266 , p. 296 – 318 . Tang , Q. , Pang , K. , Yuan , X. , and Xiao , S. , 2017 , Electron microscopy reveals evidence for simple multicellularity in the Proterozoic fossil Chuaria : Geology , v. 45 , p. 75 – 78 . Tang...
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First thumbnail for: Comment on: Tang et al. [2019]: A problematic anim...
Journal Article
Published: 31 May 2024
Journal of the Geological Society (2024) 181 (4): jgs2024-005.
... ( Javaux 2019 ; Ye et al. 2020 ). * Correspondence: [email protected] The most famous discoidal macrofossil is Chuaria   Walcott 1899 , which appeared widely in the Tonian Period ( Tang et al. 2017 ; G. Li et al. 2020 ) and can be extended back to the late Paleoproterozoic ( Hofmann...
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First thumbnail for: Discoidal carbonaceous compressions from the early...
Second thumbnail for: Discoidal carbonaceous compressions from the early...
Third thumbnail for: Discoidal carbonaceous compressions from the early...
Journal Article
Published: 01 November 1999
Jour. Geol. Soc. India (1999) 54 (5): 553–555.
... palaeontologic~l data to bring home their point of view without going into merits. They refer to the work of Maithy and Babu (1996) but have chosen only Chuaria circularis. They have not referred to other associated forms, namely Tawuia dalaensis, Sinosabellidites huainannensis, Protoarenicola baiguashanensis...