Page 437 - Petrophysics

NOMENCLATURE 405

FR = formation resistivity factor
g = gravitational constant; gram
h = height
IA = Amott wettability index
I,, = USBM wettability index
I, = resistivity index
k = absolute permeability (pm2, darcy)
LC = characteristic length for fluid imbibition
1 =length
Pc = capillary pressure
P,, = pressure of the oil phase
P, = pressure of the water phase
PC>P = pseudo capillary pressure
R = oil recovery (percent of original oil in place)
Roo = ultimate oil recovery by waterflood or imbibition
S,, = oil saturation
Sor = residual oil saturation
S, = water saturation
S,i = irreducible water saturation
t = time (minutes)
td = dimensionless time
vq = angular velocity of centrifuge rotor
V =volume
vb = bulk volume
V, = pore volume
VOt = total oil displaced by imbibition and centrifugal displacements
(Amott)
V,, = total water displaced by imbibition and centrifugal displacements
(Amott)
VOsp = oil displaced by spontaneous water imbibition (Amott)
Vwsp = water displaced by spontaneous oil imbibition (Amott)
W = pseudo work of imbibition
WR = wettability index from pseudo work of imbibition
w = pseudo work of imbibition; thermodynamic work

GREEK SYMBOLS

6 = partial derivative, or fluid displacement ratio
8 = contact angle
p = viscosity
p = density
CT = interfacial tension
‘t = adhesion tension
9 = porosity