Browsing Waterloo Research by Author "Creaser, Robert"
Now showing items 1-3 of 3
-
A Model for the Oceanic Mass Balance of Rhenium and Implications for the Extent of Proterozoic Ocean Anoxia
Sheen, Alex I.; Kendall, Brian; Reinhard, Christopher T.; Creaser, Robert; Lyons, Timothy W.; Bekker, Andrey; Poulton, Simon W.; Anbar, Ariel (Elsevier, 2018-04-15)Emerging geochemical evidence suggests that the atmosphere-ocean system underwent a significant decrease in O2 content following the Great Oxidation Event (GOE), leading to a mid-Proterozoic ocean (ca. 2.0–0.8 Ga) with ... -
Transient episodes of mild environmental oxygenation and oxidative continental weathering during the late Archean
Kendall, Brian; Creaser, Robert; Reinhard, Christopher T.; Lyons, Timothy W.; Anbar, Ariel (American Association for the Advancement of Science, 2015-11-20)It is not known whether environmental O2 levels increased in a linear fashion or fluctuated dynamically between the evolution of oxygenic photosynthesis and the later Great Oxidation Event. New rhenium-osmium isotope data ... -
Uranium and molybdenum isotope evidence for an episode of widespread ocean oxygenation during the late Ediacaran Period
Kendall, Brian; Komiya, Tsuyoshi; Lyons, Timothy W.; Bates, Steve M.; Gordon, Gwyneth W.; Romaniello, Stephen J.; Jiang, Ganqing; Creaser, Robert; Xiao, Shuhai; McFadden, Kathleen; Sawaki, Yusuke; Tahata, Miyuki; Shu, Degan; Han, Jian; Li, Yong; Chu, Xuelei; Anbar, Ariel (Elsevier, 2015-05-01)To improve estimates of the extent of ocean oxygenation during the late Ediacaran Period, we measured the U and Mo isotope compositions of euxinic (anoxic and sulfidic) organic-rich mudrocks (ORM) of Member IV, upper ...