Question

Pyroclastic rock consisting of mostly ash and less, lapilli and larger fragments.

a. ash tuff
b. tuffolava
c. ash ring
d. tuffstone
e. tuff breccia
f. none of above

Answer 1

The pyroclastic rock consisting primarily of volcanic ash, with lesser amounts of lapilli and larger fragments, is known as ash tuff.

Step-by-step explanation:

The type of pyroclastic rock you are describing, which consists mostly of volcanic ash with less lapilli and larger fragments, is known as ash tuff. Tuff is a type of rock formed from volcanic ash ejected from a volcanic eruption, which then falls to the ground, accumulates, and solidifies. When tuff is predominantly composed of ash-sized particles, it is specifically called ash tuff. It may contain glass shards or fragments of pumice. Tuff that includes larger fragments, such as those exceeding 2 millimeters in diameter, may also contain agglomerate, which includes larger volcanic fragments. If you encounter this rock, you might notice it is light colored and contains varied fragments such as pumice, biotite, and feldspar.