Clay Volume Module
Purpose
The Clay Volume module allows users to calculate the volume of clay using both single clay (GR, SP, Nphi) and dual clay (Neutron-Density, Sonic-Density, and Neutron-Sonic) indicators.
Primary Outputs
The following curves are the primary interpretations made in this module:
| Curve | Description |
|---|---|
| vwcl | Volume of wet clay |
| vshale | Volume of shale |
Screenshot showing the Clay Volume module and Neutron-Density crossplot.Discussion
Users can make interpretation of clay volume via several different methods and can set parameters using crossplots and log tracks. It is important to note that by default only vclay from gamma ray and neutron-density methods are enabled. To utilize other methods users should enable them and then set the necessary parameters.
It is generally recommended to establish a vclay using the neutron-density or similar methodology first and then adjust the endpoints in other methods to obtain a good match.
When more than one clay volume method is active the user will have the choice to either take the minimum value of each of the methods or the average value of all of the methods.
QC of results can be performed using both cross-sections and maps. The cross-section template is named "Clay Volume" and the most relevant maps are:
| Grid | Description |
|---|---|
| avg_vwcl | Average vclay for the zone |
| vwcl_net_res | Average vclay for intervals flagged as net reservoir in the zone |
| vwcl_net_pay | Average vclay for intervals flagged as net pay in the zone |
An additional video for vclay interpretation can be found here.
Related Insights
DCA: Type well curves
In this video I demonstrate how to generate a well set filtered by a number of criteria and generate a multi-well type curve. Before starting this video you should already know how to load your data and create a DCA project. If not, please review those videos. Type well curves are generated by creating a decline that represents data from multiple wells.
DCA: Loading Production data
In this video I demonstrate how to load production and well header data for use in a decline curve analysis project. The first step is to gather your data. You’ll need: Production data – this can be in CSV, Excel, or IHS 298 formats. For spreadsheet formats you’ll need columns for API, Date, Oil, Gas, Water (optional), and days of production for that period (optional). Well header data – this can be in CSV, Excel, or IHS 297 formats.
Sample data to get started
Need some sample data to get started? The files below are from data made public by the Wyoming Oil and Gas Commission. These will allow you to get started with petrophysics, mapping, and decline curve analysis. Well header data Formation tops data Deviation survey data Well log data (las files) Production data (csv) or (excel) Wyoming counties shapefile and projection Wyoming townships shapefile and projection Haven’t found the help guide that you are looking for?