Geomatic Exploration Suite — User Guide

Version 1.0.4 · Author and maintainer: Donald Annor Appiah

This plugin combines the supplied Radiometric Analysis Suite and Seismic CDP Interval Annotator into one installable package, shared menu and dock. The radiometric tools and seismic tools remain distinct workflows: neither changes the other dataset automatically.

1. Install and open

1. Install geomatic_exploration_suite.zip using Plugins > Manage and Install Plugins > Install from ZIP.
2. Enable Geomatic Exploration Suite. Open its menu under Plugins or use the toolbar icons.
3. Choose Radiometric analysis, Seismic CDP and SEG-Y tools, or User guide and methods. They open tabs in the same dock.
4. Resize, move or float the dock using QGIS's normal dock controls. Scrollbars keep the existing forms usable in a narrow dock.

The package declares QGIS 3.22 or later within QGIS 3; runtime testing is reported separately. QGIS 4 / Qt 6 compatibility is not claimed. Keep the original plugins disabled if you prefer one set of menus. The integrated radiometric provider has its own identifier, geomatic_exploration_suite, so it can be distinguished from the original provider.

Dependencies

The QGIS Python environment must include NumPy and GDAL/OGR/OSR. Matplotlib enables the radiometric plots. SEG-Y conversion additionally needs segyio; the rest of the suite can open without it. Install additional packages into the Python environment used by QGIS. For an OSGeo4W installation, use its shell:

python -m pip install segyio

Installing into a separate system Python does not make a package available to QGIS. Restart QGIS after adding a dependency.

2. Prepare a study

Use a new processing folder for each study or processing variant. Keep original rasters and navigation files separately from generated results. Check the CRS, extent, pixel size, units and NoData values before processing. Select the CRS that describes the actual input coordinates; no study location or regional CRS is assumed.

Radiometric inputs are the uranium (U), potassium (K) and thorium (Th) rasters. Their units, calibration and processing history must be compatible with the interpretation being made. An optional polygon can limit the study area. Seismic inputs are an existing CDP point layer or SEG-Y files containing usable trace-navigation headers.

3. Radiometric workflow

The Radiometric analysis tab retains the original panel's six sections: Radiometric Analysis, Work Manager, Data Analysis and QC, Stage 1 – Ratio Maps, Stage 2 – Ratio Analysis, and Stage 3 – Combined. Start with its processing folder and inputs; use Work Manager to inspect and organize generated outputs.

3.1 Input QC

1. Select the U, K and Th rasters and the processing folder.
2. Review raster statistics, histograms, CRS, resolution and valid/NoData coverage.
3. Confirm that channels align spatially. Inspect unexpected tails, spikes, zeros and negative values before treating them as geological anomalies.
4. Choose the masking and conditioning settings to match the data. Save the settings and QC outputs with the run.

3.2 Conditioning and alignment

The preprocessing algorithm uses the U raster as the reference grid and aligns K and Th to it. A mask retains that grid and writes NoData outside the polygon. Controls include an additional NoData value, exclusion of values at or below zero, optional percentile clipping, and mean or median focal filtering. Available windows range from 3 × 3 to 15 × 15 cells.

Choose the settings explicitly; smoothing and clipping can alter both anomaly shape and local amplitudes. Compare the conditioned rasters with their inputs. The Processing algorithm writes alignment, conditioning and filtered products under 02_Preprocessed.

3.3 Generate four ratio maps

Select the conditioned/filtered rasters or let the tool discover them from the processing folder. Generate:

Set the minimum denominator guard to exclude unstable division near zero. Chunked processing and the block-size control are available for large rasters. Inspect the ratio statistics and spatial patterns before continuing. QGIS display quantiles affect styling; they are not a second copy of the ratio measurements. The ratio rasters are written under 03_Ratio_Maps.

3.4 Review thresholds and extract anomalies

Open the Stage 2 review panel. Inspect each histogram and the threshold preview. U/Th, U/K and K/U use high-tail selection; K/Th uses low-tail selection. A High percentile of 85 means an upper-tail threshold at P85, while a Very Low threshold at P5 selects the lower end of the distribution.

Choose and save the threshold values, then review any trending/continuity settings and extract the anomaly rasters and polygons. Use a minimum area only when its interpretation and units are appropriate for the study. Record the threshold method and selected values with the outputs rather than assuming a particular P90/P95 convention.

3.5 Combined indices

For weighted-mean combination, the supplied tools implement:

RRAI-U  = w1*N(U/Th) + w2*N(U/K) + w3*[1 - N(K/Th)]
HRAI-KU = w1*N(U/Th) + w2*N(K/U) + w3*[1 - N(K/Th)]
HRI     = s1*z(ln(U/Th)) + s2*z(ln(U/K)) - s3*z(ln(Th/K))

N is the selected normalization. z standardizes a log ratio using the valid cells' mean and population standard deviation. Log ratios require positive values. RRAI-U and HRAI-KU also support the supplied alternative combination modes, including geometric, minimum and maximum combinations.

The supplied GUI and Processing tool have different presets. These are preserved rather than silently changing the imported scientific settings:

For comparable runs, explicitly set the same normalization, coefficients, combination method, validity mask and thresholds. Save the parameter log. HRI is a signed standardized score, so its values need not be between zero and one. These are screening indices; a radiometric anomaly alone does not establish a hydrocarbon occurrence.

3.6 Diagnostics, PCA and validation

Use the supplied ratio crossplots, source/trap diagnostics and histograms to inspect how the channels contribute to an index. The combined panel also contains PCA, loading/variance outputs, PC-score maps, quadrant products and PC1–HRI comparison controls. Interpret the component loadings before assigning geological meaning to a quadrant.

The synthetic validation tool creates a deterministic 50 × 50-cell dataset and expected outputs. Run the normal workflow using those rasters and compatible parameters, then run the processing-folder validator. Read its PASS/FAIL, missing-file and parameter-discovery results. A different preset or smoothing choice can legitimately change the comparison; a synthetic check does not validate the geological interpretation of field data.

4. Seismic CDP interval annotation

1. Load a CDP point layer with a line-name field and numeric CDP field.
2. Open Seismic / SEG-Y > CDP interval annotation and select the layer and fields.
3. Use a projected CRS in metres for kilometre spacing. Set the interval in km.
4. Choose whether to include the first point and the line endpoint.
5. Set the label template, output folder and output basename, then run.

Template tokens are {Line}, {CDP} and {Dist_km}. The tool sorts points by CDP within each line, constructs a line through those points, and places annotations at chainage intervals. It labels each interpolated position using the nearest original CDP by chainage. An annotation coordinate can therefore lie between original trace coordinates; it is not a newly measured trace point.

Check line grouping, CDP order and large navigation gaps before using the result. Crossed, repeated or incorrectly ordered navigation can produce an incorrect reconstructed line.

Keep Shapefile sidecar files together. Validate the field mapping, delimiter and CRS in the receiving Kingdom project before bulk import.

5. SEG-Y navigation conversion

1. Install segyio in QGIS's Python environment if it is not already present.
2. Open SEG-Y to points/lines, add the .sgy/.segy files and check the naming table.
3. Edit each output line name or use Auto-clean names. Renaming the output does not rename the source file.
4. Select the navigation pair: CDP_X/CDP_Y, SourceX/SourceY or GroupX/GroupY.
5. Select the CDP identifier or trace-sequence header and the trace sampling step. A step of 1 exports every trace.
6. Review coordinate-scalar handling and the option to skip missing/zero coordinates.
7. Set the CRS that actually describes the header coordinates, the label template, output folder and basename. Run and inspect the log.

Coordinate-scalar handling follows the implemented rule: positive scalar means multiply, negative scalar means divide by its absolute value, and zero means no scale change. The CRS field assigns the CRS to the coordinates; it does not transform them into another coordinate system. Do not label degree coordinates as a projected CRS merely to obtain a UTM layer.

Use projected metre coordinates for the supplied length and interval outputs. Review a few scaled header positions against known navigation control before processing many lines. The trace-navigation line is a reconstruction from the selected headers and sampling step, not a recovered acquisition survey.

SEG-Y label tokens are {Line}, {CDP}, {TraceNo} and {FileName}. The default label is {Line}_CDP_{CDP}. Exports include point and line Shapefiles, <base>_Kingdom_CDP_Points.csv and <base>_Kingdom_CDP_Points.txt. Point fields include Line, CDP, CDP_Name, TraceNo, FileName, OrigName, X, Y, Scalar and Lbl.

6. Troubleshooting

7. Sources, attribution and license

Implementation details in this guide are grounded in the supplied radiometric and seismic source code. The combined integration does not establish external scientific validation of their methods. See AUTHORS.md for component credits. Geomatic Exploration Suite is distributed under GPL-3.0-or-later; see LICENSE.

Official technical references:

• QGIS Python plugins: https://docs.qgis.org/latest/en/docs/pyqgis_developer_cookbook/plugins/plugins.html
• SEG-Y I/O library: https://github.com/equinor/segyio
• QGIS plugin publication: https://plugins.qgis.org/docs/publish