What is the term for a cross-stratified sand lens containing thin streaks of mud?

Flaser bedding is the correct term used to describe a sedimentary structure characterized by cross-stratified sand lenses that include thin streaks or laminae of mud. This type of bedding is typically formed in environments where there is a combination of opposing sedimentary processes, often between fluctuating current conditions, allowing for sand and mud to be deposited in alternating layers.

In flaser bedding, the sand is dominantly present, but the interbedded mud layers highlight the variations in depositional energy. This structure indicates a dynamic environment, such as a tidal flat or delta, where the relative strength of currents shifts, leading to the alternating deposition of sand and mud particles. Flaser bedding can be a valuable indicator of particular sedimentary conditions in geological settings.

Other options represent different bedding types and processes: lenticular bedding typically refers to sedimentary layers that exhibit a lens-like shape but are not specifically defined by the presence of mud streaks; graded bedding involves a vertical change in particle size within a single layer, indicating a decrease in energy; and ripple bedding is characterized by small ridges or ripples formed by water or wind, without the specific inclusion of mud layers seen in flaser bedding. Understanding these distinctions is crucial for interpreting sedimentary environments