Deterministic Prospect Assessment To Assess a Prospect, We Assign Numbers to the Parameters related to HC Volumes In our exercise, we have assumed the all oil case (Scenario 3) ESTIMATES Alpha Beta 1. Gross Rock Volume 2.91 km3 2.12 km3 2. Reservoir Volume 1.02 km3 0.66 km3 3. Pore Volume 0.25 km3 0.15 km3 4. In-Place Volume 0.20 km3 0.12 km3 5. In-Place – Barrels 1280 MBO 735 MBO 6. EUR – Unrisked 288 MBO 132 MBO 7. EUR – Risked MBO Slide 28 You have been working up numbers for Alpha and Beta down through line 6 1. First you estimated the gross rock volume in the trap (volume based on reservoir top minus volume based on reservoir base) 2. Then you considered the fraction of that volume that would be reservoir quality (volume * net/gross) Next you used average porosity to estimate the pore volume – space for fluids Then you factored in that only 80% of the pore space would hold oil (irreducible water in the other 20%) Next was a conversion factor to go from km3 to barrels Last, we estimated how much of the total in-place oil we can hope to get to the surface (recovery efficiency) and changes in volume as the oil goes from subsurface to atmospheric pressures (fvf) You should have gotten about 290 MBO for Alpha and about 130 MBO for Beta These numbers are approximate; they depend on how well we have assigned the various numbers These estimates assume that all the components of the HC system has worked as we think they have i.e., there is a source, it has generated large volumes of oil, there is a trap, etc. The next step is to discount these numbers based on risk – the chance that something did not work as we have hoped Unrisked means everything in the HC System has worked! Courtesy of ExxonMobil L14 – Prospect Analysis