Planar Laminated Sandstone

Typically the undulation shows no evidence of lateral accretion but only vertical aggradation and as a result most beds consist of a single laminaset.

Planar laminated sandstone.

Spacing to height ratios of the undulation are generally 100 or more. B detail of wrinkled horizontal laminae. Sandstone beds are characterized by a peculiar planar lamination showing a subtle although perceptible undulation. The horizontally bedded sandstone represents a damp sand sheet the surface of which would have been covered by a microbial mat.

Alternating episodes of deposition from high energy winds and. In geology cross bedding also known as cross stratification is layering within a stratum and at an angle to the main bedding plane. The sedimentary structures which result are roughly horizontal units composed of inclined layers. However structures from several millimetres to many centimetres.

Hence planar lamination has also been called horizontal lamination even lamination and parallel lamination. The sandstone is planar laminated and in some places ripples can be seen. Micaceous particles would fall more slowly owing to their shape thus aggregating on bedding. The term parallel lamination has also been used to describe laminae with parallel but nonplanar boundaries figure p11.

Covered with a thin layer of plastic to protect it. Planar laminated sandstone ae2 and extensive flat bedded sandstone dominated by wrinkly laminae ae3 architectural elements. Laminated light yellow to yellow colored parallel laminated sl sandstone in the middle and plannar cross stratified grayish white sandstone sp at the top chandimura section on lalmai hills. A laminated sandstone layer with tabular form interbedded with the cross stratified sandstone element ae1.

Planar laminated sandstones popularly known. The depositional environment for this unit was slow settling i e fallout without traction. C d wrinkly laminations interbedded with isolated planar. The planar laminated sandstone represents a dry sand sheet the surface of which would have been covered by granule wind ripples and climbing wind ripples.

The original depositional layering is tilted such tilting not being the result of post depositional deformation cross beds or sets are the groups of inclined. The origin of planar lamination in sands and sandstones. On parting surfaces through planar laminated sandstones parting lineation also called somewhat more precisely parting step lineation is characteristic presumably reflecting a tendency for flow parallel orientation of slightly elongated particles under upper flow regime conditions.