Stratigraphic

Seam Block Models (SBMs) are incorporated along with the associated seam modelling workflow. SBMs use blocks with variable thickness (height) to represent 3D layered deposits. Block thicknesses are entirely determined by the seams and are not limited to any given sub-blocking interval (as is the case with 3D block models). Seam splits, plies and partings are easily defined.

A Stratigraphic column display gathers together the entire stratigraphic hierarchy of the study area, and presents it in a visual and geologically familiar way. SBMs may be converted to wireframe shells for presentation output.

Stratigraphic Hierarchy

Generate Stratigraphy

Display Stratigraphy

Generate Seam File

Interpolate Seams

Insert Seams and Interburden

Extract Reference Seam

Extrapolate Reference Seam

Elevation Grid

Control File

Multiple Thickness Grid

New Grid

Create from Single Seam

Create from Multiple Seams

Combine Seam Block Models

Intersect with Surface

Intersect with Solid

Generate Waste Blocks

Recode Seams

Calculate Strip Ratio

Generate Horizons/Solids

Convert to Grid

Estimation

Report

This topic describes the workflow used to determine a coal resource statement. The functionality begins with the capture and validation of the drill logs and continues through to the modelling and classification stage.

Stage 1

• Logging
• Validation
• Sampling
• Lab Analysis
• QA/QC

Stage 2

• Down hole logs
• Down hole Geophysics
• Depth Adjustment
• Seam Correlation

Stage 3

• Import into the application
• Validate (if not done in Geobank)
• Seam Stratigraphy and Seam Block Modelling work flows

Stage 4 (for each Formation)

• Identify Reference Seam (File | Edit Data | Fields | Extract Unique)
• Breakdown seams based on Seam Stratigraphy (SS) (Stratigraphic | Seams | Interpolate Seams) Where a seam is known to consist of multiple plies, but has been logged as a single unit, it must be split into plies
• Insert Interburden Intervals (Stratigraphic | Seams | Insert Seams and Interburden)

Stage 5 (for each Formation)

• Identify Fault Zone Boundaries (or other Domains)
• Identify Tenement boundary

Stage 6 (for each Formation)

• Calculate 3D Coordinates and Extract Reference Seam (Stratigraphic | Seams | Extract Reference Seam)
• Model the stratigraphy before the first (or after the last) point of observation (Stratigraphic | Seams | Extrapolate Reference Seam)
• Grid Elevation of Reference Seam (Roof, Floor or Mid-Point) (Stats | Variograms | Omnidirectional Semi Variograms). Where there is faulting, choose the dominant fault zone
• Grid Elevation of Reference Seam (Roof, Floor or Mid-Point) (Grid/DTM | Grid Create | New Grid)
• Clip Elevation Grid to Tenement Boundary (Grid/DTM | Grid Tools | Clip)
• Calculate Omnidirectional Semi Variogram for Reference Seam (Elevation) (Stats | Variograms | Omnidirectional Semi Variograms)
• Grid Thickness of All Seams and Interburden (Grid/DTM | Grid Create | New Grid)
• Combine Grids into a Seam Block Model (SBM) (Stratigraphic | Seam Block Model | Create from Multiple Seams)

Stage 7 (if required)

• Trim blocks to topography or split at base of weathering (Stratigraphic | Seam Block Model | Intersect with Surface)

Stage 8 (for each Formation)

• Convert the SBM into a wireframe (Stratigraphic | Seam Block Model | Generate Horizons/Solids)
• Generate Resource Classification Boundaries (Drillhole | Calculations | Zones of Influence)
• Apply Classification to Seam Block Model (SBM) (Design | Polygon Tools | Polygon Assign)
• Recode seams (Stratigraphic | Seam Block Model | Recode Seams)

• Interpolate coal quality attributes (Block Model | Estimation | IDW)

• Calculate Strip Ratio (Stratigraphic | Seam Block Model | Calculate Strip Ratio)

• Report on the SBM (Stratigraphic | Seam Block Model | Report)

• Contour Seam Block Model (SBM) (Vizex | Display Layers | Contour)