Buffered, Incomplete, and Shredded: The Challenges of Reading an Imperfect Stratigraphic Record. Issue 3 (12th March 2020)

• Record Type: Journal Article
• Authors: Straub, Kyle M.; Duller, Robert A.; Foreman, Brady Z.; Hajek, Elizabeth A.
• Is Part Of: Journal of geophysical research. Volume 125:Issue 3(2020)
• Page Start: n/a
• Page End: n/a
• Publication Date: 2020-03-12
• Subjects: stratigraphy -- sedimentology -- paleoenvironment -- environmental signals -- Earth history; Geomorphology -- Periodicals; 551.3
• DOI: 10.1029/2019JF005079
• Languages: English
• ISSNs: 2169-9003

Abstract

Abstract: Climate, tectonics, and life influence the flux and caliber of sediment transported across Earth's surface. These environmental conditions can leave behind imprints in the Earth's sedimentary archive, but signals of climate, tectonic, and biologic change are not always present in the stratigraphic record. Deterministic and stochastic surface dynamics collectively act as a stratigraphic filter, impeding the burial and preservation of environmental signals in sedimentary deposits. Such impediments form a central challenge to accurately reconstructing environmental conditions through Earth's history. Emergent and self‐organized length and timescales in landscapes, which are themselves influenced by regional environmental conditions, define spatial and temporal sedimentation patterns in basins and fundamentally control the likelihood of environmental signal preservation in sedimentary deposits. Properly characterizing these scales provides a key avenue for incorporating the known "imperfections" of the stratigraphic record into paleoenvironmental reconstructions. These insights are necessary for answering both basic and applied science questions, including our ability to reconstruct the Earth system response to prior episodes of climate, tectonic, or land cover change. Plain Language Summary: Reconstructing the history of Earth prior to the age of scientific instrumentation relies heavily on interpretations of layers of sedimentary rocks, collectively called the stratigraphic record. The composition, architecture, chemistry, and fossils contained in these rocks provide signals of past climate, tectonics, and biology on Earth. However, the storage of these environmental signals in stratigraphy is not straightforward. Environmental signals can be transformed by sediment transport through channels and the landscapes that surround them. This transformation continues as sediment is deposited and strata are formed. In some cases transformation of signals severely hampers paleoenvironmental reconstruction. Recent theoretical developments allow us to model environmental signal propagation through landscapes and to estimate signal distortion or destruction during the burial process. This aids estimation of uncertainties in our paleoenvironmental reconstructions. Further improvements in our ability to quantify these uncertainties will require more detailed descriptions of the statistics and underlying physics of sediment transport and deposition. Improvements in theory, which could aid our ability to predict the statistics of sediment transport and deposition, will need to be tested against laboratory and field observations. Key Points: We review three impediments to stratigraphic storage of environmental signals that arise from Earth surface processes The magnitude of these impediments is set by emergent and self‐organized scales in landscapes, which can be predicted from stratigraphy Future work is needed to understand scales of stochasticity in a range of environments to improve our paleoenvironmental reconstructions