EUR =  \frac{Q_o}{V_o} =  \frac{ (p_i - p_{wf \, min}) \, c_t}{(1-s_{wi})\, B_o} =

 \frac{ (p_i - p_{wf \, min}) }{(1-s_{wi})\, B_o} \, \big( c_r + s_{wi} c_w + (1-s_{wi})c_o \big)

The definition of total compressibility

c_t = \frac{1}{V_{\phi}} \frac{\partial V_{phi}}{\partial p} = c_r + s_{wi} c_w + (1-s_{wi})c_o \big

and can be split into rock, water, oil components:

c_t = c_r + s_{wi} c_w + (1-s_{wi})c_o \big

For low compressible oil compressibility can be assumed constant and the volume reduction can be related to pressure decline as:

\frac{\delta V_\phi}{V_\phi} = c_t \, \delta p = c_t \, (p_i - p_{wf \, min})

\delta V_\phi = Q_o \, B_o

and

V_o = s_o \, V_\phi = (1-s_{wi}) \, V_\phi

hence

\frac{Q_o \, B_o \, (1-s_{wi})}{V_o} = c_t \, (p_i - p_{wf \, min})

and

EUR =  \frac{Q_o}{V_o} =  \frac{ (p_i - p_{wf \, min}) \, c_t}{(1-s_{wi})\, B_o}

EUR =  E_S \, E_D = E_{SV} \, E_{SH} \, E_D

E_D = \frac{1-s_{wi}-s_{or}}{1-s){wi}}

^[2]  Особенности разработки газовых и газоконденсатных залежей и влияние на нее геологических условии

^[3]  Dr. Jon Olson, Dr. Mukul Sharma, Dr. Zoya Heidari, Shale Fracturing: The Geology And Technology That Sustained The Boom