SUMMARY
(shale)
Excavation Pe8ormance
Weatherin g
(Ωm) (m/s) Pe8orman ce
Resistivity Seismic Vel ocity Excavation
Grade
I 1500 – 8000 1500 – 3000 Hard
II 800 – 5000 1000 – 3000 Moderate
III 500 – 3000 1000 – 2 000 Moderate
IV < 1000 < 1000 Easy
V 5000 – 12 000 Not detected Hard
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