Surface Crown Pillar
nounPronunciation: /ˈsɜrfɪs kraʊn ˈpɪlər/
A section of rock or ore remaining between the lowest underground excavation and the surface terrain that provides structural support and prevents surface subsidence. The integrity of crown pillars is essential for maintaining ground stability and preventing catastrophic collapse.
Plain English
The rock layer left between underground mine workings and the ground surface that prevents the mine from collapsing into a sinkhole.
Etymology & History
Usage
"Engineers assessed the surface crown pillar thickness to determine if the abandoned coal mine posed subsidence hazards to nearby homes."
Style guide notes: Always specify depth or thickness when discussing crown pillars in technical documents.
Also known as
Contrasted with
Related Terms
Frequently Asked Questions
Why are surface crown pillars important in mine reclamation?
They prevent surface subsidence and catastrophic collapses that threaten buildings, infrastructure, and public safety above mines.
How are crown pillars evaluated during closure planning?
Geotechnical surveys measure pillar thickness and rock quality to assess stability and determine appropriate remediation measures.
Why Test Candidates on This?
Essential for understanding mine closure hazards and designing appropriate surface stability interventions.
Required skill level: Mid