Eocene Paleoclimate Evolution under the Background of Warmhouse–Hothouse Conditions in the Continental Fushun Basin: Implications from Magnetic Susceptibility and Color Reflectance

Abstract

Paleocene–Eocene hyperthermal events are a current research focus in the fields of sedimentology and paleoclimatology. The Fushun Basin in northeast China contains continuous continental Eocene fine-grained rocks, and a series of Eocene hyperthermal events in the Fushun Basin have been identified. Because of the high cost of high-precision isotope data testing, it is necessary to find new and alternative paleoclimate parameters. In this study, Eocene coal and oil shale-bearing layers in the Fushun Basin are used as research objects. The high-precision data of magnetic susceptibility, color reflectance, rock composition, and cluster analyses are used to conduct a vertical comparison in the same category and compare that analysis with the identified Eocene hyperthermal events in the Fushun Basin. The preliminary results show that high-frequency-dependent susceptibility, high color reflectance a * (redness)/ L * (lightness) values, and high kaolinite content in the study area have good correspondence with global hyperthermal events and can be used as effective parameters for the identification of continental basin hyperthermal events. The detailed magnetic susceptibility and color reflectance data also reveal that the Eocene strata in the Fushun Basin recorded the Late Lutetian Thermal Maximum (LLTM) and 13 short-term hyperthermal events during the Early Eocene Climatic Optimum (EECO). These results indicate that the parameters of rock physical properties can be used to study the evolution of the paleoclimate in geological history, and it has universal practicability in continental and marine fine-grained sedimentary rocks.

Occurrence Patterns and Enrichment Influencing Factors of Trace Elements in Paleogene Coal in the Fushun Basin, China

“…(D) Geological structural units of the Fushun Basin. Reproduced with permission from ref , Copyright [2021] [Mar. Pet.…”

“…Organic-rich fine-grained sedimentary rocks are closely related to regional climate evolution and can even correspond to global climate events. − The thick coal deposits in the Fushun Basin provide a good opportunity for studying element enrichment, occurrence forms, and influencing factors in coal seams. Many researchers have conducted detailed studies on the source of organic matter, sedimentary environment, and extreme climate of coal seams in the Fushun Basin, providing a preliminary basis for this study. − However, only few studies have investigated element enrichment, occurrence forms, and sources of coal seams in the Fushun Basin.…”