fragmental

[ frag-men-tl ]

/ frægˈmɛn tl /

fragmentary.

Geology. clastic(def 3).

Origin of fragmental

First recorded in 1790–1800; fragment + -al¹

frag·men·tal·ly, adverb

These are overlaid by a series of alternating beds of crystalline (c) and fragmental (t) igneous rocks.

Geology |James Geikie
Fragmental rocks are often quite indurated—the matrix being as hard as the included stones.

Geology |James Geikie
Hence the form or outline of many of these fragmental craters is crescent-shaped.

Volcanoes: Past and Present |Edward Hull
But the walls were admitting a fragmental echo of what must have been a reverberating voice.

The Finding of Haldgren |Charles Willard Diffin

The rocks, so far as I saw them, are massive lavas, and not fragmental scori or other products of explosive eruptions.

Mount Rainier |Various

fragmental

/ (fræɡˈmɛntəl) /

(of rocks or deposits) composed of fragments of pre-existing rocks and minerals

another word for fragmentary

fragmentally, adverb