vamseeachanta Volumetrics (+3)
Volumetrics
# Stock Tank Oil Initially In Place (STOIIP)
STOIIP = 7758 * A * h * phi * (1 - Sw) / Boi # STB
# Gas Initially In Place (GIIP)
GIIP = 43560 * A * h * phi * (1 - Sw) / Bgi # SCF
Decline Curves
import numpy as np
# Exponential decline
q_exp = qi * np.exp(-D * t)
# Hyperbolic decline
q_hyp = qi / (1 + b * D * t) ** (1 / b)
# Harmonic decline (b = 1)
q_harm = qi / (1 + D * t)
Material Balance (General Form)
# F = N * Et + We - Wp * Bw
# F = underground withdrawal
# Et = total expansion
# We = water influx
STOIIP Function with Validation
def calculate_oil_in_place(
area_acres: float,
thickness_ft: float,
porosity: float,
water_saturation: float,
formation_volume_factor: float
) -> float:
"""
Calculate Stock Tank Oil Initially In Place (STOIIP).
*See sub-skills for full details.*