Pillow lava
Lava forming rounded, bulbous or lobate masses, characteristically by extrusion and chilling under water or ice.
Language and route: English descriptive compound pillow + lava; the ordinary resemblance underlies the later technical phrase. English descriptive compound pillow + lava; the ordinary resemblance underlies the later technical phrase
Literal gloss: pillow-shaped lava
The name and its history
Descriptive field term; specific original coiner unverified · nineteenth–twentieth century usage; priority unresolved
- What does the word literally mean?
- Immediate linguistic pathway: English descriptive compound pillow + lava; the ordinary resemblance underlies the later technical phrase. Relevant original form: pillow + lava (pillow + lava); conventional gloss ‘pillow-shaped lava’. The linguistic gloss should not be mistaken for the original scientist’s stated motive unless directly demonstrated.
- What did the original author mean?
- Geologists recognised rounded lobes in ancient volcanic successions and tried to establish whether they indicated subaqueous eruption.
- Why was the name needed?
- A field criterion for recognising lava that cooled against water rather than an intrusive body or ordinary terrestrial flow.
- What evidence supported the original concept?
- Repeated lobes, chilled glassy margins, radial cracks, inter-pillow sediment and inter-lobe contacts; interpretation also needs structural context.
- How has geology changed the concept?
- Pillow forms occur at seafloor ridges, in lakes and in subglacial settings; they testify to rapid external chilling, not by themselves to deep oceanic crust.
Further historical context
Geologists recognised rounded lobes in ancient volcanic successions and tried to establish whether they indicated subaqueous eruption.
A field criterion for recognising lava that cooled against water rather than an intrusive body or ordinary terrestrial flow.
Repeated lobes, chilled glassy margins, radial cracks, inter-pillow sediment and inter-lobe contacts; interpretation also needs structural context.
Pillow forms occur at seafloor ridges, in lakes and in subglacial settings; they testify to rapid external chilling, not by themselves to deep oceanic crust.
Editorial qualification
No first printed descriptive naming event verified; sources document later geological application.
Related names
Sources
- Wells, The nomenclature of the spilitic suite, 1923 (journal archive) — Secondary 1923 account of Brongniart 1827, Flett 1907 and competing classification
- Dewey & Bird (1971), Origin and emplacement of the ophiolite suite — Identified original 1971 plate-tectonic interpretation, abstract accessible; not first coining
- Anhaeusser (2014), Archaean greenstone belts review — Historical review; first greenstone/greenstone-belt usage remains qualified