page_title: Vegetation-induced sedimentary structures
section_title: Upturned beds (vegetation shadow)
hierarchical_section_title: Vegetation-induced sedimentary structures / Hydrodynamic structures / Upturned beds (vegetation shadow)
caption_attribution_description: English: Scratch circles formed as wind moved blades of grass. Photograph taken near Bethany Beach, Delaware.
context_page_description: Vegetation-induced sedimentary structures are primary sedimentary structures formed by the interaction of detrital sediment with in situ plants. VISS provide physical evidence of vegetation's fundamental role in mediating sediment accumulation and erosion in clastic depositional environments. VISS can be broken into seven types, five being hydrodynamic and two being decay-related. The simple hydrodynamic VISS are categorized by centroclinal cross strata, scratch semicircles and upturned beds. The complex hydrodynamic VISS are categorized by coalesced scour fills and scour-and-mound beds. The decay-related VISS are categorized by mudstone-filled hollows and downturned beds.
context_section_description: Upturned beds are mounds of elongated sediment that are deposited on the lee (downflow) side of an obstruction, containing form-concordant stratification. These may also be described as tongue shaped. These beds are formed where plants were once standing and caused a decrease in bed shear, allowing sediment to deposit near their base. This commonly occurs with meandering flow that deposits sediment on the lee side of a plant. Sediment is also accumulated on the front and sides of an obstruction when deposition is high.  The presence of upturned beds in cross-section is consistent with modern vegetation shadows.
caption: Scratch circle, Rygel,M.C
exif: {"Image ImageDescription": "DCF 1.0", "Image Make": "Minolta Co., Ltd.", "Image Model": "DiMAGE S404", "Image Orientation": "Horizontal (normal)", "Image XResolution": "72", "Image YResolution": "72", "Image ResolutionUnit": "Pixels/Inch", "Image Software": "Adobe Photoshop CS2 Windows", "Image DateTime": "2010:11:10 08:29:21", "Image YCbCrPositioning": "Centered", "Image ExifOffset": "248", "Thumbnail Compression": "JPEG (old-style)", "Thumbnail XResolution": "72", "Thumbnail YResolution": "72", "Thumbnail ResolutionUnit": "Pixels/Inch", "Thumbnail JPEGInterchangeFormat": "690", "Thumbnail JPEGInterchangeFormatLength": "4805", "EXIF ExposureProgram": "Program Normal", "EXIF ISOSpeedRatings": "64", "EXIF ExifVersion": "0210", "EXIF DateTimeOriginal": "2001:12:25 07:34:31", "EXIF DateTimeDigitized": "2001:12:25 07:34:31", "EXIF ComponentsConfiguration": "YCbCr", "EXIF ShutterSpeedValue": "9", "EXIF ApertureValue": "11/2", "EXIF ExposureBiasValue": "0", "EXIF MaxApertureValue": "16/5", "EXIF MeteringMode": "Pattern", "EXIF LightSource": "Unknown", "EXIF Flash": "Flash did not fire", "EXIF FocalLength": "59/8", "EXIF FlashPixVersion": "0100", "EXIF ColorSpace": "sRGB", "EXIF ExifImageWidth": "2272", "EXIF ExifImageLength": "1704", "Interoperability InteroperabilityIndex": "R98", "Interoperability InteroperabilityVersion": "[48, 49, 48, 48]", "EXIF InteroperabilityOffset": "564"}