Micromorphology of late Pleistocene and Holocene sediments and a new interpretation of the Holocene chronology at Anderson Pond, Tennessee, USA

Abstract

Thin-section (micromorphological) analysis of samples from the upper 1.5 m of a core obtained in 2007 from Anderson Pond, Tennessee, reveals a coherent but discontinuous record of late Pleistocene and Holocene climate change that supports some interpretations from previous pollen and charcoal analyses but indicates a revised Holocene chronology for this classic pollen site. Legacy sediments recording anthropogenic disturbance compose the upper 65 cm of the core (<160 cal yr BP) and are characterized by mixed, darker-colored, and coarser-grained deposits containing reworked soil aggregates, which sharply overlie finer-grained and lighter-colored, rooted middle Holocene sediments interpreted as a paleosol. These mid-Holocene sediments (95–65 cm; 7100–5600 cal yr BP) record extensive warm-dry subaerial soil conditions during the middle Holocene thermal maximum, manifested by illuviated clay lining root pores, and also contain abundant charcoal. Late Pleistocene sediments (150–95 cm), dark-colored and organic-rich, record open-water conditions and include siliceous aggregate grains at 143–116 cm (14,300–13,900 cal yr BP), recording intense fires. Thin sections are not commonly used in studies of paleoclimate from Quaternary lacustrine sediments, but we advocate for their inclusion in multianalytical approaches because they enhance resolution of depositional and pedogenic processes.

Role of latitudinal shift and climate change in evolution of red and yellow palaeosols of the Himalayas: Implications for early Oligocene seasonality and Mid‐Miocene enhanced precipitation

“…The macromorphological and micromorphological features of fossil soils and pedogenic carbonates have been successfully used to demonstrate palaeoweathering and pedogenic processes (e.g. Retallack, ; Driese et al ., , , ; Srivastava et al ., 2013a; Zhou et al ., ). Both red and yellow palaeosols show well‐developed to incipient stages of palaeopedogenesis with the presence of all four pedofacies that resulted under different weathering and pedogenic conditions.…”