An introduction to tight gas and oil in Queensland

The prospect of Queensland’s Taroom Trough being developed as a new energy frontier has captured the public’s attention, but the state already has an established gas sector, so what makes this different?

Many Queenslanders will be familiar with the growth and success of their state’s coal seam gas (CSG) industry, but the resource being explored in the Taroom Trough - ‘tight gas and oil’ - is distinct in several ways.

This article will provide insights into the key concepts and realities behind tight gas and oil development so readers can meaningfully engage with the topic.  

What is the Taroom Trough?

The Taroom Trough is an underground geological basin in central and southern Queensland, spanning between Roma and Chinchilla, that is part of the broader Bowen Basin. The formation contains thick layers of ancient sedimentary rocks that were deposited millions of years ago.

The Queensland Government has publicly described the Taroom Trough as one of the most prospective onshore oil and gas exploration regions in Australia, citing results from drilling programs in 2024-26 that indicate the presence of oil, condensates and gas.

Expert insight - Associate Professor Katherine Witt

"The Taroom Trough represents an opportunity to develop a potential new oil and gas province in Queensland at a time when reliable domestic energy supplies are increasingly important."

"At the moment development in the region is still at an exploration and appraisal stage which aim to collect a range of information about the nature of the resource and whether it can be extracted commercially."

"If proven commercially viable, developing the Taroom Trough while following Queensland's proven regulatory framework has the potential to attract more investment, create shared value for local communities, and generate government revenue."

What is tight gas and oil?

‘Tight’ gas and oil occurs in low permeability rock formations where tiny pore spaces restrict the movement of gas and liquids. Because the gas and oil does not flow readily, production typically requires technologies such as horizontal drilling and hydraulic fracturing to improve the flow and increase its access to the wellbore that extracts it. A key difference between tight gas and oil and CSG is that, while hydraulic fracturing (or fracking) may sometimes be necessary in CSG operations, it is almost always required to commercially extract tight gas and oil.

Tight gas is one of several unconventional energy resources, alongside shale gas and oil, CSG, and basin-centred gas.

Regulation and compliance

Tight gas and oil is regulated under the same framework as other onshore gas and petroleum activities in Queensland. Key legislation includes:

• Petroleum and Gas (Production and Safety) Act 2004 (Qld)
• Petroleum and Gas (Safety) Regulation 2018 (Qld)
• Petroleum and Gas (General Provisions) Regulation 2017 (Qld)
• Water Act 2000 (Qld)
• Environmental Protection Act 1994 (Qld)
• Mineral and Energy Resources (Common Provisions) Act 2014 (Qld)

A Conduct and Compensation Agreement (CCA) must be negotiated with landholders before a company can undertake advanced activities on private land for either resource type.

Well engineering is governed by the Code of Practice for the Construction and Abandonment of Petroleum Wells and Associated Bores in Queensland (RSHQ, 2019).

The Office of Groundwater Impact Assessment (OGIA) independent assessment and management of cumulative groundwater impacts in the Surat Cumulative Management Area.

Environmental considerations

Although no commercial production of tight gas and oil has occurred in Queensland, the potential environmental impacts and how they should be managed are understood due to similar developments in Australia and around the world.

Operators must hold an Environmental Authority (EA) issued by the Queensland Government before commencing operations. The EA approval process involves assessing the potential environmental risks and impacts of the proposed activities and sets conditions on how they are to be conducted, monitored and reported

Hydraulic Fracturing or ‘Fracking’

Hydraulic fracturing involves injecting mostly water and sand at high pressure into low-permeability rock formations to create small fractures that allow oil and gas to flow. In Queensland, the process is tightly regulated, with restrictions on the types and volumes of chemicals used and mandatory reporting and notification requirements.

Well integrity

Well integrity refers to a well’s ability to safely contain fluids and prevent unintended movement of gas or liquids between underground formations. Tight gas and oil wells are built with multiple layers of steel casing and cement barriers, supported by ongoing testing, monitoring and strict decommissioning requirements.

Groundwater and water usage

Resource companies are required to monitor and protect groundwater, including undertaking baseline assessments of nearby water bores before activities begin. Hydraulic fracturing can require significant volumes of water, which must be sourced through approved water authorisations, with legal mechanisms in place to address any impacts on landholder bores.

Subsidence

Subsidence, which is the gradual lowering of land surface that may occur because of resource extraction, has not been identified as a significant issue associated with tight gas and oil development. However, monitoring requirements and regulatory obligations in this area continue to evolve.

Other considerations

Tight gas and oil developments can have several other impacts, including flaring, noise, light and land disturbance. Operators must manage emissions, comply with noise and lighting limits, and progressively rehabilitate land affected by drilling, well pads, pipelines and access tracks.

Stages of development

Exploration

The Exploration and appraisal phases determine whether oil and gas resources exist and can be produced commercially. In Queensland's Taroom Trough, exploration activity is increasing, although the industry remains at an early stage.

Companies must obtain an Authority to Prospect and environmental approvals before undertaking exploration activities. Preliminary exploration activities, such as seismic surveys, soil and water sampling, and environmental assessments, are relatively low impact and can occur with notice to landholders. Advanced activities, such as drilling, require negotiated land access agreements and compensation arrangements. The most significant exploration activity is the drilling of exploration wells, which can require large well pads, heavy equipment, water storage and continuous operations over several weeks or months.

If exploration does not result in resources being found, wells are sealed and sites rehabilitated.  If oil or gas is encountered, companies may then undertake appraisal and flow testing, often involving hydraulic fracturing, to assess commercial production potential.

Exploration programs can span many years, with periods of active fieldwork followed by data analysis and assessment.

Production

Commercial tight gas and oil production involves the extraction, processing and transport of gas and oil by infrastructure such as well pads, pipelines, processing facilities, storage tanks and powerlines. Production projects typically operate for decades and require extensive approvals.

The early production phase involves the highest level of activity, with wells being drilled, hydraulically fractured and connected to infrastructure. Once wells are connected and producing, activity generally decreases significantly. Production wells operate continuously with periodic maintenance visits, while well pads are partially rehabilitated to minimise their footprint.

Water management is particularly important at this point. Operators must safely manage flowback water and wastewater under strict environmental conditions, including storage and treatment systems designed to prevent impacts on soil, surface water and groundwater.

Operators are required to monitor well integrity, groundwater and environmental conditions throughout the life of the project, with compliance overseen by regulators.

Decommissioning and rehabilitation

Decommissioning is the permanent closure, sealing and rehabilitation of a gas or oil well and associated infrastructure once it is no longer required. It is a legal requirement in Queensland, with resource companies responsible for ensuring wells are safely sealed, environmentally secure and suitable for future land use.

Decommissioning can occur at any stage of a project's life cycle, whether it’s to exploration wells or long-producing wells at the end of their economic life. The process involves placing multiple cement plugs and mechanical barriers within the well to prevent any movement of fluids or gas between underground formations, followed by the removal of wellheads and other surface infrastructure.

Rehabilitation restores the site to a condition suitable for its previous or approved future use. This includes removing infrastructure, reshaping disturbed land, reinstating topsoil, re-establishing drainage and revegetating affected areas. Rehabilitation is often undertaken progressively throughout the life of the project and completed after decommissioning.

Resource companies remain responsible for decommissioning and rehabilitation until regulators confirm the work meets required standards.