![]() ![]() 53.5 Ma) have been considered to be the prominent warming events (Kennett and Stott, 1991 Zachos et al., 2001 Lourens et al., 2005 Zeebe et al., 2016), The PETM was documented both in marine and terrestrial archives with distinct carbon isotope excursion (CIE) by −3‰ and − 7‰ (Kennett and Stott, 1991 Koch et al., 1992 McInerney and Wing, 2011), respectively, and with the total duration spanning ∼94 kyr to ∼231 kyr (Giusberti et al., 2007 Röhl et al., 2007 Murphy et al., 2010 Zeebe and Lourens, 2019 Van der Meulen et al., 2020). 56 Ma) and Eocene Thermal Maximum 2 (ETM2 ca. In a series of transient hyperthermal events in the Cenozoic Era, the Paleocene-Eocene Thermal Maximum (PETM ca. Our results indicate that chemical weathering changes were probably superceded by enhanced physical weathering and clay-mineral transport from basin margins at this continental-interior study site. The prolonged nature of smectite enhancement after the PETM event may again relate to signal propagation times that are now even longer due to lower fluvial recycling rates. The lagged response in reaching full PETM clay mineral values can be explained by the time required for upstream sediment to reach the catchment basin floodplain. Drier, hotter summers during the PETM probably caused decreased vegetation cover that, in concert with more frequent and heavier rainstorms, intensified the erosion of smectite-rich Cretaceous bentonites on the margins of the catchment, which exceeded changes in chemical weathering within the catchment. In-situ, post-depositional pedogenic clay mineral formation is similar between pre-PETM and PETM soil profiles, despite large macroscopic differences between soils that formed before and during the event. The smectite increase continued for at least 50-kyr after the event. These show an increase of detrital smectite with a lag time of 20-kyr after the main onset the PETM. Here, we investigate chemical and physical weathering and erosive flux changes through the PETM interval in the Bighorn Basin, Wyoming, a Laramide foreland basin, in a proximal continental-interior alluvial setting. However, changes in clay mineralogy can often be explained by enhanced erosion of catchment laterites during the event. Increased chemical weathering of silicate minerals is thought to be an important process removing CO 2 from the atmosphere. It can go through either a physical or chemical change.The Paleocene-Eocene Thermal Maximum (PETM) global warming event at ∼56 million years before present changed catchment weathering and erosion. The Law of matter conservation states that matter cannot be created or destroyed, only changes its form. Saturated Unsaturated and Supersaturated.Reaction Quotient and Le Chatelier's Principle. ![]() Prediction of Element Properties Based on Periodic Trends.Molecular Structures of Acids and Bases.Ion and Atom Photoelectron Spectroscopy.Elemental Composition of Pure Substances.Application of Le Chatelier's Principle.Intramolecular Force and Potential Energy.Variable Oxidation State of Transition Elements.Transition Metal Ions in Aqueous Solution.Single and Double Replacement Reactions. ![]()
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