An oil and gas investor is considering the acquisition of two fields.
Both fields have the same production profiles:
• production starts in 2013 and averages 250 barrels of oil per day (bopd) during that year
• the production ramps up and reaches a plateau production rate of 1,000 bopd in 2015
• the plateau is maintained for 5 years
• production declines by 30% per annum thereafter
• the field is abandoned at the end of the year where the average production is lower than 250 bopd

Both fields have the same cost profiles:
• over the life of the field, the capex represents $10 dollars per barrel produced
• 25% of the capex is spent in 2011, 40% is spent in 2012 and 35% is spent in 2013 (the capex is fully depreciated when spent)
• opex represents $15 per barrel produced, in the year these are produced

The investor's cash flow in both cases is defined as:
+ Field Revenue
- Field Costs
= Field Cash Flow
- Taxes
= Investor Cash Flow

The taxes are calculated as follows:
* Field 1 Tax = 30% of Field Cash Flow
* Field 2 Tax = 20% of Field Revenues

Which investment is more attractive at an oil price of:
* $35 per barrel
* $70 per barrel

What is the oil price, within the $35 to $70 per barrel range, where:
* the undiscounted Investor Cash Flow of both fields is equivalent
* the discounted Investor Cash Flow, using a 15% discount rate, of both fields is equivalent