Not only does sediment spread horizontality and from youngest (top) to oldest (bottom), it also continues to spread flat in all directions until it either runs out of material—pinches off—or hits a barrier. this is known as the
law of original horizontality
law of superposition
law of original lateral continuity
law of gravity and oppositional force
law of cross-cutting relationships

C. law of original lateral continuity

Oblique flow depicts that beds of sediment originally stretch alongside in all courses. In simple words they are continuous. Rocks that look like same are now parted by a valley or the erosion may be considered to be formally continuous.

Layers do not spread endlessly, somewhat the ends can be identified and are managed by the volume and nature of sediment possible and the mass and appearance of the sedimentary container. As sediment is moved to a domain, it will ultimately be collected. However, as the quantity of substance decreases apart from the origin, the course of that stuff will convert lighter.