ACARP ACARP ACARP ACARP
Open Cut

Structure Supermodel 2017 - Fault Characterisation in Permian to Jurassic Coal Measures

Open Cut » Geology

Published: February 18Project Number: C24032

Get ReportAuthor: Renate Sliwa, Abbas Babaahmadi & Joan Esterle | The University of Queensland

This report provides a detailed characterisation of deformation overprinting the Permian to Jurassic coal measures of Queensland. It addresses the ACARP objective to improve understanding of key aspects of Australia's coal basins and how they impact on mining conditions, by providing a consistent structural framework across the Permo-Triassic Bowen Basin. Additional work was conducted in the outlying Triassic and Jurassic basins, but these require further work to provide a more detailed structural framework.  This report, the updated edition of the Bowen Basin Structural Geology 2017 map and the time space plot of tectonic events provide an industry reference that serves to educate current and future geologists and engineers in the industry and provide a platform for effective geotechnical assessment and mine design for both open cut and underground coal mines.

 

Data were sourced from both public and proprietary seismic, drilling and underground and open pit mapping data, integrated with potential field data, coupled with the surface geology mapping from the Geological Survey of Queensland.  Subcrop patterns of the Rangal and Moranbah Coal Measures across the Bowen Basin were refined, as were the details on faults and folds in the basin. In the new edition of the map, smaller structures from the company data compilation were included if they were significant at a scale of 1: 100,000. The map is delivered as a poster, and as a fully attributed set of GIS layers (shape file format), including: solid geology, faults, folds, fault throws, dykes, basalt, sub-surface intrusives, magnetic anomalies, relief trends, and deformation domains.  

 

The coal measure rocks consist of a strongly layered succession of rock types with different strengths (coal, siltstone and sandstone) that lend themselves to deformation by flexural slip. In flexural slip deformation, all strain is focussed along narrow shear bands that are parallel to bedding, like in a bending deck of cards. The resulting folds are either concentric parallel or kinked in shape, and invariably create space problems in the hinge area, which are usually accommodated by localised fracturing or mass flow of the weakest units.

 

Most of the small-scale folding and thrust faulting occurs in thinly interbedded rocks of contrasting strengths, such as tuffaceous coal seams and siltstone/sandstone heteroliths. This is typical for flexural slip deformation, which relies on abundant layer-parallel shear planes. The tuffaceous seams and abundant heterolithic rocks of the Rangal Coal Measures are particularly prone to small-scale deformation. In the Moranbah-German Creek Coal Measures, coal seams are thicker, and very thick channel belt sandstones are common. In this environment, strain problems near the thrust faults are accommodated by fracturing and mass flow within mudstone and coal. The thrust faults themselves also tend to exploit weak bedding planes such as at the tops of coal seams, and the base of large sandstones to propagate through the coal measures.

 

Joints were studied to provide information for local deformation, weathering, prediction of permeability, and geotechnical effects on the rock stability and strength. One of the main joint types in the Bowen Basin include large joints which are observed in thick interburden sandstones and in some locations, continue through other heterolithic units as well. One possibility for large joints is that they occur within the damage zone of major fault zones, which are intensely fractured areas. Another possibility is that large joints cut through the layers with low contrast in competency and therefore, rocks behave almost the same in response to strain.

 

Observations from high walls show that large joints control the frequency of smaller joints along various scan-lines. Joints are more abundant and more closely spaced close to large joints within both thicker and thinner beds. These observations at the regional scale for large scale faults and folds, and smaller scale joint sets, provide a context within which to investigate features that affect coal measure stability upon extraction.

Underground

Health and safety, productivity and environment initiatives.

Recently Completed Projects

C21013Improving Cavity Prediction On Longwall Faces Through A Combination Of Reliable Convergence, Canopy Attitude And Leg Pressure Monitoring

Most Australian coal mines have shield leg pressure monitoring in real t...

C24014Distributed Acoustic Conveyor Monitoring

CRC Mining have investigated the application of fibre optic Distribu...

C25054Distributed Acoustic Conveyor Monitoring - Phase 2

This project is phase 2 of the distributed acoustic sensing project ...

Underground

Open Cut

Safety, productivity and the right to operate are priorities for open cut mine research.

Recently Completed Projects

C23053A Study Of Sustainability And Profitability Of Grazing On Mine Rehabilitated Land In The Upper Hunter NSW

This study was initiated by the Upper Hunter Mining Dialogue (UHMD) ...

C25035Coal Subsurface Mapping For Open Cut Selective Mining

A reliable coal seam sensing system is required to improve the produ...

C23025Coal Pit Lake Closure By River Flow Through: Risks And Opportunities

In 2011, the river diversion channel around Lake Kepwari, a former o...

Open Cut

Coal Preparation

Maximising throughput and yield while minimising costs and emissions.

Recently Completed Projects

C26007 Revised Dustiness And DEM Test Method (Update Of AS4156.6) Part 2:Preparation

In 2015 project C23054 investigated and reviewed the Australian Stan...

C22033Advanced Control And Optimisation Of DMC Operation

The objective of this project was to develop, implement and demonstr...

C24045Adaptation Of Coal Grain Analysis To Improve Flotation Yield Estimation

Yield estimation from resource data is notoriously difficult. Facto...

Coal Preparation

Technical Market Support

Market acceptance and emphasising the advantages of Australian coals.

Recently Completed Projects

C25045Stage Two - Assessment Of In Situ High-Temperature Strength Of Cokes

Stage I of this project established a reliable and repeatable proces...

C25044Trace Elements In Coal; Status Of Test Methods In Use And Their Applicability

 STAGE 1 REPORT

The key objectives of this stage...

C25042Mechanistic Model Of Coke Development In A Coke Oven Situation

The standard approach to evaluate the potential of coals or blends t...

Technical Market Support

Mine Site Greenhouse Mitigation

Mitigating greenhouse gas emissions from the production of coal.

Recently Completed Projects

C24061Proof-Of-Concept Photocatalytic Destruction Of Methane For Coal Mining Fugitive Emissions Abatement

Australia's fugitive emissions in 2015 were 41 Mt CO2-e (representin...

C23052Novel Stone Dust Looping Process For Ventilation Air Methane Abatement - Phase 3

This multi‐phase project is concerned with the mitigation of m...

C19054VAM Enrichment With A Two-Stage Adsorption Process

Treatment of ventilation air methane (VAM) with cost-effective technolog...

Mine Site Greenhouse Mitigation

Low Emission Coal Use

Step-change technologies aimed at reducing greenhouse gas emissions.

Recently Completed Projects

C17060BGasification Of Australian Coals

Four Australian coals were trialled in the Siemens 5 MWth pilot scale ga...

C17060AOxyfuel Technology For Carbon Capture And Storage Critical Clean Coal Technology - Interim Support

The status of oxy-fuel technology for first-generation plant is indicate...

C18007Review Of Underground Coal Gasification

This report consists of a broad review of underground coal gasification,...

Low Emission Coal Use

Mining And The Community

The relationship between mines and the local community.

Recently Completed Projects

C16027Assessing Housing And Labour Market Impacts Of Mining Developments In Bowen Basin Communities

The focus of this ACARP-funded project has been to identify a number...

C22029Understanding And Managing Cumulative Impacts Of Coal Mining And Other Land Uses In Regions With Diversified Economies

The coal industry operates in the context of competing land-uses that sh...

C23016Approval And Planning Assessment Of Black Coal Mines In NSW And Qld: A Review Of Economic Assessment Techniques

This reports on issues surrounding economic assessment and analysis ...

Mining And The Community

NERDDC

National Energy Research,Development & Demonstration Council (NERDDC) reports - pre 1992.

Recently Completed Projects

1609-C1609Self Heating of Spoil Piles from Open Cut Coal Mines

Self Heating of Spoil Piles from Open Cut Coal Mines

1301-C1301Stress Control Methods for Optimised Development...

Stress Control Methods for Optimised Development and Extraction Operations

0033-C1356Commissioned Report: Australian Thermal Coals...

Commissioned Report: Australian Thermal Coals - An Industry Handbook

NERDDC