Clay veins : their occurrence, characteristics, and support
Advanced Search
Select up to three search categories and corresponding keywords using the fields to the right. Refer to the Help section for more detailed instructions.

Search our Collections & Repository

For very narrow results

When looking for a specific result

Best used for discovery & interchangable words

Recommended to be used in conjunction with other fields



Document Data
Clear All
Clear All

For additional assistance using the Custom Query please check out our Help Page


Clay veins : their occurrence, characteristics, and support

Filetype[PDF-3.38 MB]



  • Personal Author:
  • Corporate Authors:
  • Description:
    "Clay veins found in coal mines have caused numerous injuries and fatalities. These structures plague all phases of mining, including entry development, pillar recovery, and panel extraction. Clay veins also increase production costs and may disrupt or halt mining. These detrimental aspects have prompted the Bureau of Mines to investigate the physical characteristics of and roof instability problems associated with clay veins. This was accomplished by observing and mapping clay veins in surface and underground mines. The occurrence and origins of clay veins were also investigated to determine predictive capabilities. The investigators found that clay veins normally occur in more stable, less rapidly subsiding coal basins. Clay veins result when tensile stresses develop fissures that are later infilled. These fissures can be propagated by compactional processes and/or tectonic stresses during and subsequent to coalification. The Bureau also found that associated faults, fractures, and slickenside planes commonly parallel clay veins and disrupt the lateral continuity of the immediate and, sometimes, main roof. When clay veins parallel or subparallel the direction of face advance, the roof is segmented into cantilever beams, causing unstable conditions. Consequently, the strata on either side of the clay veins should be bolted and strapped together to form a beam." - NIOSHTIC-2

    NIOSHTIC no. 10005605

  • Subjects:
  • Series:
  • Document Type:
  • Collection(s):
  • Main Document Checksum:
  • Download URL:
  • File Type:

Supporting Files

  • No Additional Files
More +

You May Also Like

Checkout today's featured content at