Question

Volumetric Reserves Estimation The Stock-tank Oil Initially in Place (STOTIP) is the amount of oil that is stored in an oil reservoir. Assuming that the pore spaces in the reservoir are filled with water and oil only, the STOTIP can be estimated using the formula: STOLIP = 7758Ah (1 - S..)/B where A is the area of the reservoir in acres, h is the reservoir thickness in feet (ft). s is the initial water saturation of the reservoir. It is the ratio of the volume of water initially in the reservoir to the total pore volume in the reservoir. It can either be expressed as a fraction or percentage B is the initial oil formation volume factor. It is the ratio of the volume of oil at reservoir conditions (measured in units of reservoir barrels, rb) to the volume of oil at standard conditions (measured in units of stock tank barrels, stb). This means that the unit of Bois is the porosity of the reservoir. It is the ratio of the pore volume to the bulk volume, and can be expressed as a fraction or in percentage. 7758 is the conversion factor from acre-ft to barrels (bblor rb) NOTE: You should be able to show that the unit of STOLIP from this equation is stb. 1. Given the values below, write a Python code that calculates and stores the STOTIP into a variable named "stoiip, and then prints the STOTIP value. A = 250 in acres (store this value in a variable called "area") h 50 in feet (store this value in a variable called "h") -0.33 fraction (store this value in a variable called "poro") S =0.25 fraction (store this value in a variable called 'swi") B</em>oi - 1.1 #rb/stb (store this value in a variable called "b_01") In : 1. The bulk volume of the reservoir (BV or V) in units of acro-It is given as: BV - Ah Write a Python code that computes and stores the BV in a variable called "by_acroft". Print this variable In [ ]: 1. Write a Python code to convert the BV from (2) above to barrels (b) using the given conversion factor and store this in a variable called "bv_rb'. Print this variable In [ ]:

Answer 1

# -*- coding: utf-8 -*-
"""
Created on Sun Sep 1 22:31:51 2019

@author: Ashwini
"""
## part 1
area=250
h=50
poro = 0.33
swi = 0.25
b_oi = 1.1

stoiip = (7758*area*h*poro*(1-swi))/b_oi
print("STOIIP = " + str(stoiip))

## part 2
bv_acraft = area*h
print("BV - acre-feet = " + str(bv_acraft))

## part 3
bv_rb = bv_acraft *7758
print("BV in barrels = " + str(bv_rb))

## part 4
#since poro is the ratio of pore volume to bulk volume
v_p_acraft = bv_acraft*poro
v_p_rb = bv_rb * poro
print("Pore vol.-acre-feet = " +str(v_p_acraft)+";Pore vol.-barrels ="+str(v_p_rb))

##part 5
#hcpv = 7758*A*h*poro*(1-swi)
# since v_p_rb is already a product of 7758*A*h*poro
hcpv = v_p_rb*(1-swi)
print("HCPV = " +str(hcpv))

#part6
#one line python code to assign values
poro_B , poro_C = 0.25 , 0.35
stoiip_B = (7758*area*h*poro_B*(1-swi))/b_oi
stoiip_C = (7758*area*h*poro_C*(1-swi))/b_oi

#3mean to 3 reservoirs stoiip
mean_stoiip = (stoiip + stoiip_B + stoiip_C)/3.0

##using freater than operator
print(stoiip_B>stoiip_C)

## adding 10% of stoiip_B to its value using += operator
stoiip_B +=0.1*stoiip_B

##fast python code to update stoiip_c to 90% of its value
stoiip_C = 0.9*stoiip_C