Pendleton Colliery Floor Heave, 1925

At 3,550 feet — among the deepest workings in Britain — the floor of Pendleton Colliery's Rams seam suddenly heaved upward without warning, killing six men in a genuine rockburst, or 'crump'.

Cause

A 'crump' — a sudden, violent upward heave of the mine floor at extreme depth, confined between the coal face and the goaf (worked-out area). Investigators found that the warrant, a shale layer underlying the Little Rams seam, had been thrust violently upwards, though the harder grey sandstone beneath it remained unbroken.

What happened

At Morris's Level and Bramwell's Level, around 3,550 feet below the surface — among the deepest workings in Britain — the floor of Pendleton Colliery's Rams seam suddenly and violently heaved upward on 4 November 1925, with no warning. One witness described the sensation as being 'picked off my feet just as though you were stood on a plank and someone snatched the plank from under you'. The floor lifted across the entire length of the face, confined between the coal face and the worked-out goaf behind it. Six men were killed: Samuel Corbett, Stephen Morris, Edward Ditchfield, Frank Bramwell, Robert Hanrahan and Radcliffe Holden. The colliery had experienced similar, lesser crumps before at depths beyond 3,000 feet, but this was the most severe. In the aftermath, the colliery's fireman located a pocket of firedamp around 70 yards inbye from Morris's Brow, released by the crump, and dispersed it using compressed air from a nearby haulage engine; prior inspections that day had found no gas present at all.

Investigation & inquiry

Investigators determined the warrant — a shale layer underlying the Little Rams seam — had been thrust violently upward by the crump, while the harder grey sandstone beneath it remained unbroken; the Rams seam itself was six feet thick at this exceptional depth.

Memorials & commemoration

A memorial bench and two plaques naming the colliery's dead were unveiled at St Thomas' Church, Pendleton, in November 2024, marking the approaching centenary of the disaster.

Recorded claims

Individual factual claims, each attached to the source(s) that support it below. Where sources disagree, both are kept.

• Six men died: Samuel Corbett, Stephen Morris, Edward Ditchfield, Frank Bramwell, Robert Hanrahan and Radcliffe Holden. A separate 2024 news source states eight deaths for the same incident. (disputed) ^1,2
• A sudden, violent upward heave of the mine floor ('crump') struck without warning at 3,550 feet, lifting the floor across the entire face length between the coal face and the worked-out goaf; investigators found the underlying shale 'warrant' layer had been thrust violently upward. ¹
• The crump released a pocket of firedamp around 70 yards from Morris's Brow, dispersed by the colliery's fireman using compressed air from a nearby haulage engine; no gas had been found in inspections earlier that day. ¹
• A memorial bench and two plaques naming the colliery's dead were unveiled at St Thomas' Church, Pendleton, in November 2024. ²

Related terminology

Mining terms this disaster is structurally linked to, with the nature of the relationship.

• Colliery (contextual relationship)
  Named 5 times in this record, first in the summary: “…— among the deepest workings in Britain — the floor of Pendleton Colliery's Rams seam suddenly heaved upward without warning, killing six men…”
• Firedamp (hazard involved)
  The crump released a pocket of firedamp, which the colliery's fireman had to disperse using compressed air, though the gas was not itself the cause of any fatalities in this incident.
• Fireman (contextual relationship)
  Named in this record’s narrative: “…feet, but this was the most severe. In the aftermath, the colliery's fireman located a pocket of firedamp around 70 yards inbye from Morris's…”
• Goaf (contextual relationship)
  Named twice in this record, first in the cause: “…mine floor at extreme depth, confined between the coal face and the goaf (worked-out area). Investigators found that the warrant, a shale…”
• Level (contextual relationship)
  Named twice in this record, first in the narrative: “At Morris's Level and Bramwell's Level, around 3,550 feet below the surface — among…”

Sources

1. (primary) Pendleton Colliery Floor Heave — Pendleton — 1925 — Northern Mine Research Society
2. (secondary) Pendleton Colliery memorial bench revealed in tribute to coal miners — Salford Now

Record created: 2 September 2026 · Last researched: 2 September 2026