Mudrock line
In rock physics and petrophysics, the mudrock line, also called Castagna's equation or Castagna's relation, is an empirical linear relation between seismic P-wave velocity and S-wave velocity in brine-saturated siliciclastic rocks (i.e. sandstones and shales).
The equation reads:
\[V_p = 1.16 V_s + 1.36\]
Where \(V_p\) and \(V_s\) refer to P-wave velocity and S-wave velocity, respectively[1]. Velocities are given in kilometers per second (km/s).
The name of the equation refers to John Castagna, professor of exploration geophysics at the University of Houston[2], who discovered the relation while working for ARCO, an oil company that is now a subsidiary of BP.
References
- ↑ Script error
- ↑ http://www.geosc.uh.edu/people/faculty/john-castagna/index.php "University of Houston directory"
