Gravity and Magnetic Interpretation

A number of gravity and magnetic interpretation tools are available to estimate magnetic and density source geometries and depths from gridded magnetic and gravity data.

Euler 3D streamlines geological interpretation by delineating magnetic and gravimetric boundaries and estimating source depths in gridded magnetic and gravity data using Euler 3D deconvolution routines.

Specialized Source Depth Estimation Tools

  • Kimberlite tools use a series of straightforward techniques to identify potential kimberlite targets from residual magnetic intensity data. The extension includes the Keating Magnetic Correlation Coefficients function, commonly used in kimberlite exploration. This tool applies a pattern-recognition approach to detect magnetic anomalies that resemble the response of a vertical cylinder model—typical of kimberlite pipes.

  • Source Edge Detect (SED) tools identify edges (for example, geological contacts) or peaks in potential field data by analyzing local gradients.

  • Source Parameter Imaging (SPI) tools calculate the depth of magnetic sources from gridded magnetic data. The resulting depths are displayed as a grid and are derived from source parameters based on the following models: contacts (faults), thin sheets (dikes), and horizontal cylinders.

The help system for Kimberlite, Source Edge Detect, and Source Parameter Imaging is separate from the main Oasis montaj help system. It can be accessed through the extension menus and individual GXs/dialogs.

Open a New Project

Working in Oasis montaj requires a project file (*.gpf). A project encompasses all items in your workspace, including:

  • Data files (for example, databases, grids, maps, voxels, geosurfaces, and 3D views)

  • Visualization tools such as histograms and scatter plots

  • Project settings, including the menus currently displayed

This structure ensures that your working environment is saved and can be easily restored.

To begin working with an extension, open a new project and then load the corresponding menus.

  1. On the Project menu, click New. The New Project dialog opens.

    Alternatively, select Create new project from the startup dialog when you launch Oasis montaj.

  2. In the New Project dialog, specify the name and location for your project file (*.gpf), then click Save.

  3. The new project opens, enabling the main menus, toolbar icons, and the Project Explorer. These visual indicators confirm that the system is ready for use.

Load the Menus

  1. On the Project menu, select Manage Menus, or click the Manage Menus icon on the Project Explorer toolbar. The Manage Menus dialog opens.

  2. In Base Menus, expand the Interpretation node, select the applicable extensions under Analysis Tools, and click OK. The corresponding menus will be added to the main menu bar.

The menu system is designed to provide quick access to a variety of tools and guide you through key interpretation workflows.

To automatically load these menus in future projects, specify them in the Default menus field of the General Settings dialog.

Accessing Help

Once the menus are loaded, click the Help button in any dialog opened from these menu items to open the referenced topic for the current dialog.

In the Oasis montaj help system:

  • Use the Help Topics tab to navigate to other topics of interest.

  • Use the Search tab to find specific topics by entering keywords.

Additional Resources

To learn more about using the Gravity and Magnetic Interpretation extensions, consult the Oasis montaj User Guide for Grav/Mag Interpretation Extension, which is available for download from the Seequent Learning Centre.