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Your search keyword '"Blättler, C. L."' showing total 8 results
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8 results on '"Blättler, C. L."'

1. Two-billion-year-old evaporites capture Earth’s great oxidation

Author

Blättler, C. L., Claire, M. W., Prave, A. R., Kirsimäe, K., Higgins, J. A., Medvedev, P. V., Romashkin, A. E., Rychanchik, D. V., Zerkle, A. L., Paiste, K., Kreitsmann, T., Millar, I. L., Hayles, J. A., Bao, H., Turchyn, A. V., Warke, M. R., and Lepland, A.

Published
2018

2. A Reference Section for the Otavi Group (Damara Supergroup) in Eastern Kaoko Zone near Ongongo, Namibia.

Author

Hoffman, P. F., Pruss, S. B., Blättler, C. L., Bellefroid, E. J., and Johnson, B. W.

Subjects
CHEMOSTRATIGRAPHY, RIFTS (Geology), LITHOFACIES, GLACIATION, EROSION, CARBON isotopes
Abstract

A reference section for the Otavi Group (Damara Supergroup) in the East Kaoko Zone near Ongongo is proposed and described. The section is easily accessible, well exposed, suitable for field excursions, and well documented in terms of carbonate lithofacies, depositional sequences and stableisotope chemostratigraphy. The late Tonian Ombombo Subgroup is 355 m thick above the basal Beesvlakte Formation, which is not included in the section due to poor outcrop and complex structure. The earlymiddle Cryogenian Abenab Subgroup is 636 m thick and the early Ediacaran Tsumeb Subgroup is 1020 m thick. While the section is complete in terms of formations represented, the Ombombo and lower Abenab subgroups have defined gaps due to intermittent uplift of the northward-sloping Makalani rift shoulder. The upper Abenab and Tsumeb subgroups are relatively thin due to erosion of a broad shallow trough during late Cryogenian glaciation and flexural arching during post-rift thermal subsidence of the carbonate platform. [ABSTRACT FROM AUTHOR]

Published
2021

3. Identifying vital effects in Halimeda algae with Ca isotopes

Author

Blättler, C. L., Stanley, S. M., Henderson, G. M., and Jenkyns, H. C.

Subjects
lcsh:Geology, lcsh:QH501-531, lcsh:QH540-549.5, lcsh:QE1-996.5, lcsh:Life, lcsh:Ecology
Abstract

Geochemical records of biogenic carbonates provide some of the most valuable records of the geological past, but are often difficult to interpret without a mechanistic understanding of growth processes. In this experimental study, Halimeda algae are used as a test organism to untangle some of the specific factors that influence their skeletal composition, in particular their Ca-isotope composition. Algae were stimulated to precipitate both calcite and aragonite by growth in artificial Cretaceous seawater, resulting in experimental samples with somewhat malformed skeletons. The Ca-isotope fractionation of the algal calcite (−0.6‰) appears to be much smaller than that for the algal aragonite (−1.4‰), similar to the behaviour observed in inorganic precipitates. However, the carbonate from Halimeda has higher Ca-isotope ratios than inorganic forms by approximately 0.25‰, likely because of Rayleigh distillation within the algal intercellular space. In identifying specific vital effects and the magnitude of their influence on Ca-isotope ratios, this study suggests that mineralogy has a first-order control on the marine Ca-isotope cycle.

Published
2014

4. Refinement of Miocene sea level and monsoon events from the sedimentary archive of the Maldives (Indian Ocean)

Author

Betzler, C., primary, Eberli, G. P., additional, Lüdmann, T., additional, Reolid, J., additional, Kroon, D., additional, Reijmer, J. J. G., additional, Swart, P. K., additional, Wright, J., additional, Young, J. R., additional, Alvarez-Zarikian, C., additional, Alonso-García, M., additional, Bialik, O. M., additional, Blättler, C. L., additional, Guo, J. A., additional, Haffen, S., additional, Horozal, S., additional, Inoue, M., additional, Jovane, L., additional, Lanci, L., additional, Laya, J. C., additional, Hui Mee, A. L., additional, Nakakuni, M., additional, Nath, B. N., additional, Niino, K., additional, Petruny, L. M., additional, Pratiwi, S. D., additional, Slagle, A. L., additional, Sloss, C. R., additional, Su, X., additional, and Yao, Z., additional

Published
2018
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8. Constraints on ocean carbonate chemistry and pCO2in the Archaean and Palaeoproterozoic

Author

Blättler, C. L., Kump, L. R., Fischer, W. W., Paris, G., Kasbohm, J. J., and Higgins, J. A.

Abstract

One of the great problems in the history of Earth’s climate is how to reconcile evidence for liquid water and habitable climates on early Earth with the Faint Young Sun predicted from stellar evolution models. Possible solutions include a wide range of atmospheric and oceanic chemistries, with large uncertainties in boundary conditions for the evolution and diversification of life and the role of the global carbon cycle in maintaining habitable climates. Increased atmospheric CO2is a common component of many solutions, but its connection to the carbon chemistry of the ocean remains unknown. Here we present calcium isotope data spanning the period from 2.7 to 1.9 billion years ago from evaporitic sedimentary carbonates that can test this relationship. These data, from the Tumbiana Formation, the Campbellrand Platform and the Pethei Group, exhibit limited variability. Such limited variability occurs in marine environments with a high ratio of calcium to carbonate alkalinity. We are therefore able to rule out soda ocean conditions during this period of Earth history. We further interpret this and existing data to provide empirical constraints for carbonate chemistry of the ancient oceans and for the role of CO2in compensating for the Faint Young Sun.

Published
2016
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