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12 Chapter 12Figure 12.1 A simple model of the sedimentary cycle.Figure 12.2 (a) Thin laminations (above) and thicker beds (below) in the Jur...Figure 12.3 Major terrestrial, paralic, and marine depositional environments...Figure 12.4 Laminar and turbulent flow profiles; flow lines are dashed.Figure 12.5 Transition from laminar flow (background) to turbulent flow (for...Figure 12.6 Hjulstrom's diagram showing velocity conditions for entrainment ...Figure 12.7 Sediment loads in an idealized aqueous medium.Figure 12.8 A simplified version of the flow regime concept: (a) lower flow ...Figure 12.9 Current ripples. (a) Asymmetrical current ripples on a modern be...Figure 12.10 Slightly wavy‐crested sand waves or subaqueous dunes, Rio Hondo...Figure 12.11 Antidunes in phase with standing waves on a flow surface. Antid...Figure 12.12 Flow regimes with respect to mean flow velocity and grain size....Figure 12.13 Ripple migration by stoss‐side erosion and lee‐side deposition ...Figure 12.14 Progressive increases in trough climb rates due to bed aggradat...Figure 12.15 Climbing ripple laminations produced by down‐current (left to r...Figure 12.16 Tabular sets of planar cross‐strata. (a) Formation by aggrading...Figure 12.17 (a) Wedge sets and trough sets of festoon cross‐strata formed b...Figure 12.18 Plane bed transition. (a) View of a plane bed under shallow uni...Figure 12.19 Upper flow regime and antidunes. (a–d) Antidunes in laboratory ...Figure 12.20 (a) Deep water waves showing roughly circular orbitals whose di...Figure 12.21 Oscillatory flow and sand movement (left in a, then right in b)...Figure 12.22 (a) Oscillation ripple marks showing crest bifurcation, symmetr...Figure 12.23 (a) Oscillation ripples in the Carboniferous Horton Group, Nova...Figure 12.24 Interlayered ripple‐laminated sandstone and mudstone from tidal...Figure 12.25 (a) Block diagram showing hummocky cross‐stratification (HCS). ...Figure 12.26 Major modes of sediment transport by winds: creep, saltation, a...Figure 12.27 Velocity conditions for wind erosion, transportation by suspens...Figure 12.28 Typical loess deposit; note the paucity of stratification in co...Figure 12.29 Wind ripples on back‐beach sand dunes, Australia, with branchin...Figure 12.30 Major types of sand dunes: transverse, barchan, parabolic, star...Figure 12.31 Formation of eolian cross‐strata by dune migration. (a) Dune sh...Figure B12.1 Map of West Antarctic Ice Sheet (WAIS) and East Antarctic Ice S...Figure 12.32 Erosion of bedrock by glacial plucking and glacial abrasion.Figure 12.33 Striated bedrock surface in Cambrian dolostones, northwest New ...Figure 12.34 (a) Glacial till, Pleistocene, Ohio; note the polymictic compos...Figure 12.35 Glacial varves from the Pleistocene, Maine: coarser, lighter co...Figure 12.36 Large glacial dropstone and other ice‐rafted debris from the Pl...Figure 12.37 (a) Mud flow with matrix strength sufficient to suspend boulder...Figure 12.38 (a) Debris flow deposit above an erosion surface, southern Utah...Figure 12.39 Turbidity current in a laboratory showing the head and main bod...Figure 12.40 (a) Model of a turbidity current with a head, main body, and ta...Figure 12.41 (a) Classic Bouma sequence showing an erosional base overlain b...Figure 12.42 Sole marks on bed bases. (a) Flute marks, Austen Glen Formation...