Neoproterozoic Chuar Group (∼800–742Ma), Grand Canyon: a record of cyclic marine deposition during global cooling and supercontinent rifting

Dehler, Carol M.; Elrick, Maya; Karlstrom, Karl E.; Smith, Gary A.; Crossey, L. J.; Timmons, J. Michael

doi:10.1016/s0037-0738(01)00087-2

Cited by 61 publications

(63 citation statements)

References 63 publications

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“…There is no sedimentological evidence for major fluvial deposits. In fact, tidal influence is reported throughout the section [19] suggestive of a low estuarine Richardson number. 98 Mo of global seawater [21], and encourages the use of Mo isotopes to track global ocean redox conditions in the past from restricted marine basins.…”

Section: A221 Solution 2: Riverine Dilution and Globally Oxic Oceansmentioning

confidence: 97%

“…Even this fast removal feedback, we will see, is not enough to drive open ocean Mo concentrations below the thresholds where nitrogen fixation can limit global primary production, and thus y>1 becomes hard to envision. parameter values with euxinic shelves (<8% seafloor) lead to long marine residence time 175 scales (>30,000 years) compared to ocean mixing time scales (~1,500 yr [19]). Hence, 176…”

Section: Mo Concentration and Residence Time For The Direct Feedback mentioning

confidence: 99%

“…It has been suggested that the low δ 98 1) Local sea level increased markedly during Walcott times [19], and the connection to the open ocean was likely at its maximum during times of basinal euxinia. This conforms to independent lines of evidence for a marine deposition environment, which are summarized in the main text (including the globally significant microfossil assemblage observed in many other marine basins worldwide).…”

Section: A221 Solution 2: Riverine Dilution and Globally Oxic Oceansmentioning

confidence: 99%

“…This stratification is at odds with the extreme supply of river water that is needed in order to generate deceptively low Mo Chuar basin (W) is given from today's exposure, 10 km [19]. There is no sedimentological evidence for major fluvial deposits.…”

Section: A221 Solution 2: Riverine Dilution and Globally Oxic Oceansmentioning

confidence: 99%

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Molybdenum evidence for expansive sulfidic water masses in ~750Ma oceans

Dahl

Canfield

Rosing

et al. 2011

Earth and Planetary Science Letters

103

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Section: A221 Solution 2: Riverine Dilution and Globally Oxic Oceansmentioning

confidence: 97%

Section: Mo Concentration and Residence Time For The Direct Feedback mentioning

confidence: 99%

Section: A221 Solution 2: Riverine Dilution and Globally Oxic Oceansmentioning

confidence: 99%

Section: A221 Solution 2: Riverine Dilution and Globally Oxic Oceansmentioning

confidence: 99%

See 2 more Smart Citations

Molybdenum evidence for expansive sulfidic water masses in ~750Ma oceans

Dahl

Canfield

Rosing

et al. 2011

Earth and Planetary Science Letters

103

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“…Dolomite-capped cycles are common features in shallow-water carbonates and have been reported throughout the geologic record (Goldhammer et al, 1990;Montañez and Read, 1992;Yoo and Lee, 1998;Bosence et al, 2000;Dehler et al, 2001). Their patterns, processes, and timing frequently play a key role in understanding the development of carbonate platforms.…”

Section: Introductionmentioning

confidence: 99%

Early diagenetic dolomitization and dedolomitization of Late Jurassic and earliest Cretaceous platform carbonates: A case study from the Jura Mountains (NW Switzerland, E France)

Rameil

2008

Sedimentary Geology

104

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Early diagenetic dolomitization is a common feature in cyclic shallow-water carbonates throughout the geologic record. After their generation, dolomites may be subject to dedolomitization (re-calcification of dolomites), e.g. by contact with meteoric water during emersion. These patterns of dolomitization and subsequent dedolomitization frequently play a key role in unravelling the development and history of a carbonate platform. On the basis of excellent outcrops, detailed logging and sampling and integrating sedimentological work, high-resolution sequence stratigraphic interpretations, and isotope analyses (O, C), conceptual models on early diagenetic dolomitization and dedolomitization and their underlying mechanisms were developed for the Upper Jurassic / Lower Cretaceous Jura platform in north-western Switzerland and eastern France. Three different types of early diagenetic dolomites and two types of dedolomites were observed. Each is defined by a distinct petrographic/isotopic signature and a distinct spatial distribution pattern. Different types of dolomites are interpreted to have been formed by different mechanisms, such as shallow seepage reflux, evaporation on tidal flats, and microbially mediated selective dolomitization of burrows. Depending on the type of dolomite, sea water with normal marine to slightly enhanced salinities is proposed as dolomitizing fluid. Based on the data obtained, the main volume of dolomite was precipitated by a reflux mechanism that was switched on and off by high-frequency sea-level changes. It appears, however, that more than one dolomitization mechanism was active (pene)contemporaneously or several processes alternated in time. During early diagenesis, percolating meteoric waters obviously played an important role in the dedolomitization of carbonate rocks that underlie exposure surfaces. Cyclostratigraphic interpretation of the sedimentary succession allows for estimates on the timing of early diagenetic (de)dolomitization. These results are an important step towards a better understanding of the link between high-frequency, probably orbitally forced, sea-level oscillations and early dolomitization under Mesozoic greenhouse conditions.

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Ediacaran microfossils from the Doushantuo Formation chert nodules in the Yangtze Gorges area, South China, and new biozones

Moczydłowska

2019

Fossils and Strata

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Neoproterozoic Chuar Group (∼800–742Ma), Grand Canyon: a record of cyclic marine deposition during global cooling and supercontinent rifting

Cited by 61 publications

References 63 publications

Molybdenum evidence for expansive sulfidic water masses in ~750Ma oceans

Molybdenum evidence for expansive sulfidic water masses in ~750Ma oceans

Early diagenetic dolomitization and dedolomitization of Late Jurassic and earliest Cretaceous platform carbonates: A case study from the Jura Mountains (NW Switzerland, E France)

Ediacaran microfossils from the Doushantuo Formation chert nodules in the Yangtze Gorges area, South China, and new biozones

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