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Table 2 Values of fracture density and physical properties for each interval in the footwall

From: Multiple damage zone structure of an exhumed seismogenic megasplay fault in a subduction zone - a study from the Nobeoka Thrust Drilling Project

Interval footwall Depth (mbgs) Fracture density total/density (number per 1 m) Porosity (%) Resistivity (Ω m) Density (g cm −3 ) P -wave velocity (km s −1 ) Gamma ray (API) Cementation exponent m
Footwall unit 1 (42.1 to 80 mbgs)         
Intact zone 41.8 to 66.7 245/10 7.6 232 2.72 4.25 123 0.60
Damage zone 66.7 to 75, 80 to 85.7 102/7 7.8 241 2.71 4.34 124 Upper: 1.07, Lower: 0.92
Brecciated zone 75 to 80 43/9 10.9 166 2.65 3.94 125 0.82
Footwall unit 2 (80 to 112 mbgs)         
Intact zone 85.7 to 95 96/11 7.6 226 2.70 4.25 125 0.95
Damage zone 95 to 112, 115 to 124 249/10 7.6 251 2.70 4.19 123 Upper: 0.80, Lower: 0.96
Brecciated zone 112 to 115 25/9 31 80 2.08 2.29 94 0.36
Footwall unit 3 (112 to 180 mbgs)         
Intact zone 124 to 134, 174 to 180 121/8,354/9 7.2 281 2.72 4.29 126 1.00
Damage zone 134 to 157, 159 to 174 354/9 7.2 330 2.71 4.40 127 Upper: 1.22, Lower: 0.88
Brecciated zone 157 to 159 011/6 10.9 168 2.65 3.96 128 0.26
Footwall unit 4-1 (180 to 196.6 mbgs)         
Intact zone 180 to 184.6 25/6 7.1 255 2.72 4.39 126 0.56
Damage zone 184.6 to 188, 189 to 196.6 73/7 6.7 270 2.73 4.50 126 Upper: 1.00, Lower: 1.00
Brecciated zone 188 to 189 14/16 8.4 205 2.69 4.10 124 0.72
Footwall unit 4-2 (196.6 to 221.2 mbgs)         
Intact zone 196.6 to 201.8 54/11 6.4 283 2.71 4.57 128 0.79
Damage zone 201.8 to 210, 212 to 221.2 167/10 7.0 281 2.72 4.34 128 Upper: 0.95, Lower: 1.12
Brecciated zone 210 to 212 20/10 9.4 209 2.59 3.55 123 0.49
Footwall unit 4-3 (221.2 to 255 mbgs)         
Intact zone 221.2 to 222.5, 247.3 to 255 73/8 6.4 234 2.73 4.61 126 0.79
Damage zone 222.5 to 242, 243 to 247.3 179/8 6.6 228 2.73 4.46 127 Upper: 1.42, Lower: 0.86
Brecciated zone 242 to 243 13/13 10.2 101 2.65 3.58 123 0.58
  1. Depth, fracture total number distribution, fracture density (number of fractures per 1 m), neutron porosity, resistivity, density, P-wave velocity, natural gamma ray values, and Archie’s cementation exponent m for the intact zones, surrounding damage zones, and the brecciated zones in the footwall are presented.