hyaloclastite
|hy-a-lo-clas-tite|
🇺🇸
/ˌhaɪəloʊˈklæstaɪt/
🇬🇧
/ˌhaɪələˈklæstaɪt/
glassy broken volcanic rock
Etymology
'hyaloclastite' originates from Ancient Greek, specifically the combining elements 'hyalo-' from 'hyalos' meaning 'glass' and 'klastos' meaning 'broken', plus the suffix '-ite' (from Greek 'lithos' via Latin/French) meaning 'stone'.
'hyaloclastite' was coined in 20th‑century geological literature by combining Greek elements to name brecciated glassy volcanic deposits; earlier descriptions of similar materials used terms like 'glassy breccia' or 'pillow breccia'.
Initially it literally meant 'glass-broken-stone' from its Greek components, but over time it evolved to denote the specific volcanic rock composed of quenched glass fragments produced by interaction of lava with water or ice.
Meanings by Part of Speech
Noun 1
a volcaniclastic rock consisting mainly of glassy fragments (shards, angular clasts) produced by the quench-fragmentation of lava when it contacts water or ice; commonly formed during submarine or subglacial eruptions and often occurs as breccia-like deposits.
The coastal cliff exposed layers of hyaloclastite formed during repeated submarine eruptions.
Last updated: 2025/10/15 02:48