Add rock: default values are wacky

[kwinkunks]

I think the Dashboard > Add rock defaults are Vp 3000, Vs 2000, rho 1500 — not very realistic

Propose: Vp 2000, Vs 1000, rho 2000.

Or, perhaps better, just leave them blank.

Perhaps the rho SD should be 25 kg/m^3 — pretty sure it should be smaller than velocity.

[EvanBianco]

Also need better default values for pore fluids.

Kw = 2.2 GPa, Koil ~ 1.9 (but highly variable)

Rho_hc default is 250, which is quite low (I think)

Best to link to some pressure/temperature diagrams for hydrocarbon liquids, gases, and brines, from Batzle and Wang (1992) and other classic papers:

examples at http://petrowiki.org/Pore_fluid_properties

Bulk modulus

Density