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Prehistoric landscape mapping along the Scheldt by camera- and conductivity CPT-E
Published in Michael A. Hicks, Federico Pisanò, Joek Peuchen, Cone Penetration Testing 2018, 2018
J. Verhegge, Ph. Crombé, M. van den Wijngaert
As such, a primary aim of the prehistoric landscape evaluation is a reconstruction of the topography of the top of the Pleistocene sedimentary sequence. Secondly, it has to be determined to what degree later sedimentation has protected this paleo-surface or if erosion has destroyed it as well as the prehistoric sites this paleosurface might contain. Due to sea level rise and surfacing local ground water levels, depressions in the landscape were first covered by Late Atlantic alder carr peat. Peat development was interrupted by a short period of organic rich and clayey supratidal freshwater floodplain sedimentation, after which a sedge fen and birch carr formed. Further acidification resulted in an oligotrophic peat layer (Deforce et al., 2014). From the middle ages onwards, the increased influence of the sea caused erosion of the prehistoric landscape and covered it with varying sandy to clayey estuarine floodplain sediments as successive embankment attempts gradually claimed the land from the sea (Missiaen et al., 2016 and references therein).
Warrumbungle Volcano: facies architecture and evolution of a complex shield volcano
Published in Australian Journal of Earth Sciences, 2021
K. F. Bull, A. L. Troedson, S. Bodorkos, P. L. Blevin, M. C. Bruce, K. Waltenberg
The Keelindi beds and Drildool beds are informal units based on a simplified stratigraphy for the southern Surat Basin suggested by Hawke and Cramsie (1984). We did not recognise either unit at any of our field sites during this study. Regionally the Keelindi beds consist of fine- to coarse-grained quartzose to quartz–lithic arenite, pebbly sandstone and conglomerate with minor shale, siltstone and coal interbeds, and are interpreted to represent a transition to a lower energy fluvial system in the Late Jurassic (Hawke & Cramsie, 1984). The overlying Drildool beds are composed of fine-grained lithic sandstone, siltstone, mudstone and minor coal, most likely deposited in a coastal plain to intertidal environment (Hawke & Cramsie, 1984). The distribution of Surat Basin sequences on a regional scale indicates a shallow northwest regional dip in the project area (e.g. Offenberg, 1968). A long period of exposure and weathering of the basin sequences began in the Late Cretaceous and extended through the Paleogene, resulting in deep weathering and a ferruginised paleosurface (duricrust) widely developed on the Pilliga Sandstone.
Early Cretaceous glacial environment and paleosurface evolution within the Mount Painter Inlier, northern Flinders Ranges, South Australia
Published in Australian Journal of Earth Sciences, 2020
S. B. Hore, S. M. Hill, N. F. Alley
At Streitberg Ridge, the breccias are crudely horizontally laminated (Figure 10b) and appear to have been deposited on a saddle of fractured crystalline bedrock. On the adjoining southwestern slope, the breccia bodies dip steeply to the south, whereas further down on the northeastern slope, the tabular hematitic breccia dips 30–40°N, similar to on the upper slopes of Mt Ward. Their opposed attitude is thought to reflect original variations in the local breccia–basement contact. Although the central portion of breccia between Mt Ward and Streitberg Ridge has been almost completely removed by erosion, the evident contrast in attitude of these proximal breccias indicates that their form is due to draping over a paleosurface rather than folding.