What causes Flaser bedding to form?
Flaser beds are a sedimentary, bi-directional, bedding pattern created when a sediment is exposed to intermittent flows, leading to alternating sand and mud layers. Individual sand ripples are created, which are later infilled by mud during quieter flow periods.
What is wavy bedding?
A form of heterolithic sediment characterized by interbedded rippled sands and mud layers. Wavy beds are commonly found on storm-dominated shelves (see shelf), but also in lakes, intertidal areas, and other environments where energy levels fluctuate appreciably.
How is lenticular bedding formed?
Lenticular bedding is a sedimentary bedding pattern displaying alternating layers of mud and sand. Formed during periods of slack water, mud suspended in the water is deposited on top of small formations of sand once the water’s velocity has reached zero.
What causes wavy bedding?
Wavy bedding occurs when mud is deposited over the whole area of a bed of rippled and/or cross stratified sand. It usually loosely follows the alternating concave-convex nature of the ripples creating a wavy appearance. In wavy bedding the ripples are laterally discontinuous.
Why is cross bedding important?
Cross bedding forms on a sloping surface such as ripple marks and dunes, and allows us to interpret that the depositional environment was water or wind. Examples of these are ripples, dunes, sand waves, hummocks, bars, and deltas.
What is the difference between cross bedding and graded bedding?
Cross-beds form as sediments are deposited on the leading edge of an advancing ripple or dune. Each ripple advances forward (right to left in this view) as more sediment is deposited on its leading face. Graded bedding is characterized by a gradation in grain size from bottom to top within a single bed.
What does graded bedding indicate?
Graded bedding simply identifies strata that grade upward from coarse-textured clastic sediment at their base to finer-textured materials at the top (Figure 3). The stratification may be sharply marked so that one layer is set off visibly from those above and beneath it.
What is massive bedding geology?
Massive Bedding – Beds of sedimentary rock contain few or no visible forms or structures. Graded Bedding – Strata characterized by gradual but distinct vertical changes in grain size. This is strata in which internal layers dip at a distinct angle to the surface that bound the sets of cross-beds.
What is the cause of graded bedding?
Graded beds form when a steep pile of sediment on the sea floor (or lake floor) suddenly slumps into a canyon or off a steep edge. As the sediment falls, water mixes in with it, creating a slurry of sediment and water that flows quickly down a sloping bottom. When the bottom levels out, the flow begins to slow.
What is the difference between layering and bedding?
While Bed refers to the bottom of the soil, Layer refers to the levels of the soil. In sedimentary rocks a number of minerals occur in these, so formed as a result of processes such as- deposition, accumulation and concentration in horizontal strata.