Subsurface Magnetic Sensor Archaeological Magnetometer

The Data Processing Specialist – From Raw Readings to Interpretable Models

The value of any geophysical survey lies not in the raw measurements but in the processed interpretations derived from them. For the data processing specialist, the WCZ-3 is a welcome departure from instruments that produce messy, undocumented, or proprietary-format data. This version focuses on how the WCZ-3 simplifies and streamlines the processing pipeline, allowing more time for interpretation and less for data cleaning.

Clean Data from the Start – The WCZ-3’s real-time quality assessment ensures that the data arriving at the processing desk have already been vetted in the field. The quality score (0-10) is recorded for each station; the specialist can filter out low-scoring measurements at the start of processing. This pre-screening eliminates the need for laborious manual outlier detection. The temperature log and GPS fix quality indicators provide additional context for identifying suspect readings, such as those taken during a satellite geometry degradation.

Complete Metadata in a Usable Format – Each measurement record contains: UTC timestamp, magnetic field (nT), latitude, longitude, elevation, quality score, temperature, and GPS PDOP/satellite count. The CSV text format is directly importable into any geophysical processing environment. The specialist can use Python scripts (Pandas, ObsPy), R, or commercial packages (Oasis montaj, Geosoft) without any conversion tool. The standardized column ordering and ISO 8601 time format facilitate automated workflows.

Diurnal Correction Made Systematic – The WCZ-3’s GPS-disciplined clock ensures that base station and mobile readings share a common time reference. The included software performs automated diurnal correction by matching the mobile survey’s timestamps to the base station’s time series. The specialist can also export the base station data to an external file for use in alternative correction algorithms (e.g., using a regional magnetic observatory data). The software retains both raw and corrected values, allowing the specialist to assess the correction’s impact.

Gridding and Continuation – The software provides multiple gridding algorithms: minimum curvature, kriging, and inverse distance weighting. The specialist can choose the method best suited to the survey’s spatial sampling. The software also supports upward and downward continuation for depth estimation and trend separation. The contour map generation includes customizable levels, color palettes, and labeling options suitable for publication.

Profile Extraction and Modeling – For linear anomalies (e.g., dykes, faults, pipelines), the software can extract profiles along any user-defined line. These profiles can be exported to forward modeling software (e.g., ModelVision, Potent) to test geological hypotheses. The Euler deconvolution and analytic signal functions provide initial source depth estimates, guiding more detailed modeling.

Quality Control Reports – The software can generate a QC report summarizing: total stations, rejected stations (by quality score threshold), station spacing statistics, base station drift, and diurnal correction magnitude. This report is essential for project documentation and client deliverables. The report is generated as a PDF with embedded tables and graphs, ready for inclusion in final reports.

Batch Processing for Large Datasets – Surveys with hundreds of thousands of stations (common in UAV or large-scale ground surveys) require efficient batch processing. The WCZ-3 software supports command-line batch mode, allowing automated processing of multiple files. The specialist can set up a processing workflow that runs overnight, delivering grid and contour outputs by morning.

Long-Term Archiving – The raw CSV files are self-describing and require no proprietary reader. The specialist can archive the data in a secure repository, confident that it will remain readable for decades. The metadata completeness also ensures that future re-processing (e.g., after improvements in diurnal correction models) can be performed without revisiting field notes.

For the data processing specialist, the WCZ-3 is not just an instrument; it is a well-behaved data source that fits seamlessly into modern geophysical computing workflows, minimizing the time spent on data wrangling and maximizing the time available for geological interpretation.