Table 4 Differential response of rock permeability performance.
From: Investigation of change coal seam floor permeability based on pressurized water testing
P-Q curve type | Absolute change in permeability(\(\:{q}_{\text{P}5}-{q}_{\text{P}1}\)) (Lu) | k | \(\:{k}_{\text{Y}1}/{k}_{\text{Y}2}\) (Calculation result after removing * data) | ||||
|---|---|---|---|---|---|---|---|
Y1 | Y2 | Y1 | Y2 | Y1 | Y2 | ||
Carbonaceous mudstone | A | - | 1.43 | - | 86.72% | - | - |
A | - | 1.04 | - | 90.53% | - | ||
Bauxite mudstone | A | D | 0.47 | 16.85 | 94.55% | 11.32% | −29.59 (8.52) |
A | D | 0.17 | 17.25 | 98.16% | −17.83%* | ||
Fine sandstone | D | E | 0.33 | 0.00 | 96.35% | 100.00% | 1.20 |
A | D | −1.11 | 0.00 | 113.45% | 100.00% | ||
D | A | −0.88 | 0.15 | 112.31% | 98.09% | ||
C-E | E | 1.34 | 0.00 | 85.79% | 100.00% | ||
C-E | D | −0.46 | 3.04 | 111.92% | 48.21% | ||
- | E | - | 1.08 | - | 73.07% | ||
Benxi limestone | C | B-D | 0.19 | 2.75 | 88.34% | 20.06% | 4.92 (1.27) |
E | A | −5.64 | −0.11 | 594.74%* | 118.64% | ||
Coal No.10 | A | B-E | −0.39 | 0.00 | 105.34% | 100.00% | 1.05 |
Bauxite rock | A | D | 0.08 | 3.61 | 99.06% | 38.01% | 2.09 |
D | D | −0.29 | 2.77 | 103.70% | 55.82% | ||
D | D | 0.00 | 3.48 | 100.00% | 39.70% | ||
D | D | −0.24 | 3.67 | 104.71% | 60.37% | ||
D | - | 0.00 | - | 100.00% | |||
Ordovician limestone | D | D | 0.00 | 8.88 | 100.00% | 4.37% | 4.59 |
D | D | 0.00 | 8.35 | 100.00% | 5.86% | ||
D | D | 0.00 | 6.04 | 100.00% | 33.84% | ||
D | D | 0.00 | 5.85 | 100.00% | 43.04% | ||
