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Table 6 Seismic Impedance (Pa s/m) for compressional-waves propagating perpendicular to the bedding planes of the sedimentary formations (plugs in Z-direction)

From: A laboratory approach for the calibration of seismic data in the western part of the Swiss Molasse Basin: the case history of well Humilly-2 (France) in the Geneva area

Core

Sample

Depth (m)

Rock-type (age)

Seismic Impedance (\(\times 10^{7}\)Pa s/m)

\({-\!\!\!\!Z}_{0}\)

\({-\!\!\!\!Z}_{\text {BHP}}\)

Core I

HU01

1015.0

Limestone (Upper Jurassic)

1.47

1.33

HU03

1018.1

1.93

1.28

HU06

1020.1

1.32

1.20

Core II

HU07

1853.4

Argillaceous limestone (Middle Jurassic)

1.51

1.44

HU09

1860.8

1.46

1.34

HU12

2003.5

1.55

1.42

Core III

HU13

2242.7

Shale (Liassic)

1.25

1.17

HU14

2468.3

Limestone (Lower Jurassic)

1.61

1.59

Core IV

BX107

2630.0

Anhydrite-Claystone-Halite (Upper Triassic)

1.23

1.45

CL126

2710.0

1.10

1.11

GDHlt

2770.0

1.05

1.02

Core V

HU17

2905.5

Dolomite Anhydrite (Middle Triassic)

1.81

1.81

HU20

2922.5

1.85

1.84

HU21

2930.3

1.69

1.66

HU24

2967.0

1.93

1.89

HU25

3028.3

Sandstone (Lower Triassic)

1.42

1.36

HU26

3030.2

1.46

1.44

HU27

3037.5

Sandstone (Permo-Carboniferous)

1.55

1.52

HU29

3038.8

1.50

1.48

  1. Seismic Impedance is calculated as a function of intrinsic seismic velocities, \({-\!\!\!\!Z}_{0}\), as well as at the Bottomhole Pressure, \({-\!\!\!\!Z}_{\text {BHP}}\). The in-situ seismic velocity was derived following Wepfer and Christensen (1991) relationship (Eq. 7) in text and using the parameters A, B, a, and b provided in Table 4)