Interpex Ix1d V350 ((new)) -

Mastering the Depths: A Complete Guide to the Interpex IX1D v350 for Geophysical Resistivity Sounding

Core Functionality

The primary purpose of IX1D is to take field data collected from the surface and calculate the likely layering of the earth underneath the measurement point. It operates on a 1D layered earth model, assuming the ground consists of horizontal layers of varying thickness and resistivity.

The software handles three main categories of data:

1. DC Resistivity & IP (Induced Polarization): It interprets data from vertical electrical soundings (VES). This includes data from common array types such as: interpex ix1d v350

   • Schlumberger
   • Wenner
   • Dipole-Dipole
   • Pole-Dipole

2. Frequency Domain EM (FDEM): It processes data from electromagnetic systems that measure in-phase and quadrature components. This includes support for popular instruments like:

   • Geonics EM-31, EM-34, and EM-38
   • DUALEM systems

3. Time Domain EM (TDEM): It interprets transient electromagnetic data, which is often used for deep sounding applications. Mastering the Depths: A Complete Guide to the

---

Future Outlook: Will There Be a v360 or v400?

Interpex has hinted at releasing a 64-bit version to handle larger datasets and integrate with GIS workflows. However, the v350 build is stable, and the company focuses on bug fixes rather than feature creep. For users needing 2D inversion, Interpex offers IX2D; for TEM data, IX1D-TEM. The v350 designation will likely remain current for several years.

Step 2: Initial Model Building

Before inversion, you must guess an initial layered model. Using the "Forward Model" module: DC Resistivity & IP (Induced Polarization): It interprets

• Input number of layers (typically 3 to 8 for shallow environmental surveys).
• Assign initial resistivity (using the last apparent resistivity value as a semi-infinite half-space).
• Assign initial thickness (often a geometric progression, e.g., 1m, 3m, 9m).
• Click "Calculate" to overlay the forward response on your field data.

The delta between your field curve and the forward curve guides manual adjustments.

Optimizing Your Workflow: Power Tips for v350

To extract maximum value from Interpex IX1D v350, implement these advanced techniques:

• Use the “Joint Inversion” Capability (Hidden Feature): While not advertised, v350 can simultaneously invert VES and TEM (time-domain electromagnetic) data if the TEM data is formatted as pseudo-resistivity. This breaks equivalence problems dramatically.
• Script the Batch Mode: Create a text batch file referencing multiple .DAT files. IX1D v350 command-line flags (-a, -i, -o) allow fully automated inversion. Example: IX1D.exe -i survey1.dat -o survey1.out -m 4
• Calibrate with Boreholes: After inversion, use the “Constraints” menu to fix resistivity values of dry sand or clay based on direct push probe data. This forces the software to adjust only layer thicknesses, yielding geologically realistic results.