At the base of the sequence you find a rock (sample 9). It f…

At the bаse оf the sequence yоu find а rоck (sаmple 9). It feels like coarse sandpaper against your fingers. Inspect sample 9 further. Visual Description The rock is tan to sandy beige in colour and has a clearly granular, sandy texture, with tiny visible grains across its surface. The grains appear uniform in size and well sorted, giving the rock a relatively even appearance. Across the face of the rock are several subtle, wavy, parallel lines that run roughly horizontally from left to right. These lines are slightly darker or more shadowed than the surrounding surface and appear as gentle ripples or laminae, suggesting internal layering or sedimentary structures such as ripple marks or cross-bedding. The surface is matte and slightly rough, with no visible crystals or shiny minerals. The rock appears moderately compact but still shows individual sand grains, especially near the edges. The green ruler beneath the rock shows centimeter markings, indicating that the rock is roughly several centimeters long, providing a sense of scale.