火山碎屑

Also known as volcanoclastic rock, volcaniclastic material, volcanoclastic material, volcaniclastics

thumb|upright=1.35|The Espinaso Formation includes a wide variety of volcaniclastic materials. Volcaniclastics are geologic materials composed of broken fragments (clasts) of volcanic rock. These encompass all clastic volcanic materials, regardless of what process fragmented the rock, how it was subsequently transported, what environment it was deposited in, or whether nonvolcanic material is mingled with the volcanic clasts. The United States Geological Survey defines volcaniclastics somewhat more narrowly, to include only rock composed of volcanic rock fragments that have been transported so