Volumetrics
The Volumetrics Wizard can calculate the total volume of a structure, the contact area, and generate areadepth pairs by using just a top (single) or a top plus a base (dual), and a flat contact.
If reservoir characteristics such as net/gross, porosity, and fluid data are entered, the wizard also calculates fluid in place and recoverable hydrocarbon volumes.
Calculations made with the Volumetrics wizard include:
 Contact area
 Gross rock volume (GRV)
 Net volume
 Pore volume
 Hydrocarbon volume
 Stock tank oil in place (STOIIP)
 Recoverable oil volume
 Oil and gas in place (OGIP)
 Recoverable gas volume
The results are presented in a table for copying into a report, text editor or spreadsheet.
Defining Volumetrics Parameters
In the single case, the volume (shaded) is calculated between a single top surface and a flat contact.
In the dual case, the volume (shaded) is calculated between a pair of surfaces defining the top and base of the structure, and a flat contact.
 Use Required (link) parameters to define the top and base of the structure and specify a range of contacts and an interval to output results. This will generate a table of areadepthGRV at specific intervals throughout a structure.
 Add Optional (link) parameters so that reservoir information such as net/gross, porosity, and fluid properties can be included to calculate in place and recoverable hydrocarbons.
Required parameters
Adjust these parameters to define the top and base of the structure and specify a range of contacts and an interval to output results. This will calculate areadepthGRV at specific intervals throughout a structure.

Top Structure: Choose a horizon or specify a constant to define the top of the structure.
 If a horizon is chosen, an offset distance above or below (TVD) can be added.
 The horizon must be in depth or convertible to depth (see How it Works (TimeDepth Conversion)).
 Base Structure: ("Dual" case only): Choose a horizon or specify a constant to define the base of the structure.

Contact(s): Choose Horizon, Constant, or Multiple Constants to define the contact.
 Horizon: a horizon with optional depth offset
 Constant: a depth value (TVDSS)

Multiple Constants: one or more depth values (separated by commas) AND/OR a sequence (as minmax[step] format).
 e.g. 1000.0  1400.0 [100.0]
 e.g. 1100, 1275, 1300  1400 [50]
 Units: Choose the units to use for the output, including oil and/or gas volumes if Oil and/or Gas ratios are provided.

Polygon: Constrain the area of calculation with a map polygon. If a polygon is not selected, the area is defined by the entire horizon.
 A polygon must be selected if constants are used for the structure and contact(s).
Note: Volumetrics calculates the Gross Rock Volume (GRV) unless the following optional parameters are specified.
Optional parameters
Fill in these parameters so that reservoir information such as net/gross, porosity, and fluid properties can be used to calculate in place and recoverable hydrocarbons.
Note: For the remaining parameters, provide a single constant or a horizon to define a spatially varying value. Porosity and Water Saturation are interpreted as ratios (0 to 1) or as percentages (0 to 100) if any value in the horizon is greater that 1.
 Provide Net/Gross Ratio to calculate net volume. Valid range: 0.0 to 1.0.
 Provide Porosity to calculate pore volume. Valid range: 0.0 to 1.0 (or 0.0 to 100.0).
 Provide Water Saturation to calculate hydrocarbon volume. Valid range: 0.0 to 1.0 (or 0.0 to 100.0).
 Provide Oil Formation Volume Factor (also called shrinkage factor), to calculate stock tank oil originally/initially in place (STOOIP/STOIIP). This parameter converts the volume of oil at reservoir conditions to the volume at the surface. The value varies depending on the fluid and the temperature and pressure of the reservoir and the surface. Typical values are from 1 to 1.7.
 Provide Oil Recovery Factor to calculate estimated ultimate recovery (EUR) volume. Valid range: 0.0 to 1.0.
 Provide Gas Formation Volume Factor, to calculate original gas in place (OGIP/GIIP). This parameter converts the volume of gas in the reservoir into the volume at the surface. The value varies depending on the fluid and the temperature and pressure of the reservoir and the surface. Typical values are below 0.1.
 Provide Gas Recovery Factor to calculate estimated ultimate recovery (EUR) volume. Valid range: 0.0 to 1.0.
Note: If a horizon is provided as the structure or contact, the horizons must all be consistent. For example, if a horizon has an undefined location, each horizon provided must have the same undefined location within the polygon (if selected).
Click Next to perform the volumetrics calculation.
Results
The results are calculated using the equations below:
 Contact Area = The total area of the contact as it intersects with the volume.
 Net Volume = GRV x Net/Gross Ratio
 Pore Volume = Net Volume x Porosity
 Hydrocarbon Volume = Pore Volume x (1 Water Saturation)
 STOOIP/STOIIP = Hydrocarbon Volume / Oil Formation Volume Factor
 Recoverable Oil Volume = STOIIP x Oil Recovery Factor
 OGIP = Hydrocarbon Volume / Gas Formation Volume Factor
 Recoverable Gas Volume = OGIP x Gas Recovery Factor
Note: the following constants are used to convert to Billions Cubic Feet (Bcf) and Million Barrels(MMbbl)
 OGIP: 1 Bcf= 28316846.592 m^3, 28.317 km^2.m, 22956.8411 acreft
 STOIIP: 1 MMbbl= 158987.295 m^3,0.158987 km^2.m,128.893 acreft
Copy the content to the clipboard by rightclicking anywhere in the window and selecting Copy.
Click Finish to close the Volumetrics wizard.
Example 1: Generating areadepth pairs at a specific TVD interval
In this example we’ll create a table of areadepth pairs based off a top structure horizon and multiple contacts at a 10 m interval. This table can then be copied into a spreadsheet, text editor, or other program.
 Select single so that only a Top structure and contacts need to be defined.
 In the Required parameters, enter your horizon and specify multiple contacts
 Enter a depth range that the structure enclose. To output a result at a specific interval, enter an increment. For this example, we’ll use a range and increment of 30003200 [10]
 Optionally add a polygon to define the closure of the structure.
 Click Next to generate the results.
Example 2: Generate a table of fluid volumes in place and recoverable hydrocarbon volumes using additional reservoir data.