Multi-isotope studies investigating recharge and inter-aquifer connectivity in coal seam gas areas (Qld, NSW) and shale gas areas (NT)

2020 ◽  
Vol 60 (1) ◽  
pp. 335
Author(s):  
Axel Suckow ◽  
Alec Deslandes ◽  
Christoph Gerber ◽  
Sebastien Lamontagne ◽  
Dirk Mallants ◽  
...  
Keyword(s):  
Coal Seam ◽  
Shale Gas ◽  
Oil And Gas ◽  
Spatial Scales ◽  
Scientific Evidence ◽  
Environmental Isotopes ◽  
Sedimentary Basins ◽  
Coal Seam Gas ◽  
Tracer Studies ◽  
Aquifer Systems

Large sedimentary basins with multiple aquifer systems like the Great Artesian Basin and the Beetaloo Sub-Basin are associated with large time and spatial scales for regional groundwater flow and mixing effects from inter-aquifer exchange. This makes them difficult to study using traditional hydrogeological investigation techniques. In continental onshore Australia, such sedimentary aquifer systems can also be important freshwater resources. These resources have become increasingly stressed because of growing demand and use of groundwater by multiple industries (e.g. stock, irrigation, mining, oil and gas). The social licence to operate for extractive oil and gas industries increasingly requires robust and reliable scientific evidence on the degree to which the target formations are vertically and laterally hydraulically separated from the aquifers supplying fresh water for stock and agricultural use. The complexity of such groundwater interactions can only be interpreted by applying multiple lines of evidence including environmental isotopes, hydrochemistry, hydrogeological and geophysical observations. We present an overview of multi-tracer studies from coal seam gas areas (Queensland and New South Wales) or areas targeted for shale gas development (Northern Territory). The focus was to investigate recharge to surficial karst and deep confined aquifer systems before industrial extraction on time scales of decades up to one million years and aquifer inter-connectivity at the formation scale. A systematic and consistent methodology is applied for the different case study areas aimed at building robust conceptual hydrogeological models that inform groundwater management and groundwater modelling. The tracer studies provided (i) in all areas increased confidence around recharge estimates, (ii) evidence for a dual-porosity flow system in the Hutton Sandstone (Queensland) and (iii) new insights into the connectivity, or lack thereof, of flow systems.

PESA industry review—2009 environmental update

2010 ◽  
Vol 50 (1) ◽  
pp. 143
Author(s):  
Sue Slater
Keyword(s):  
Climate Change ◽  
Coal Seam ◽  
Greenhouse Gas ◽  
Oil And Gas ◽  
Renewable Energy Sources ◽  
South Australia ◽  
Final Report ◽  
Coal Seam Gas ◽  
Geological Sequestration ◽  
The Government

This paper provides a brief update on some of the key environmental issues that arose during 2009. In Queensland, activity is dominated by coal seam gas projects and specifically coal seam gas (CSG) to liquefied natural gas (LNG) projects. Environmental milestones for these projects are discussed, and the State Government’s response policy and regulation development response is reviewed. The progress of the more conventional LNG projects in Western Australia and the Northern Territory is also discussed. The final report on the mandated ten year review of the Environment Protection and Biodiversity Conservation Act 1999 was released in December 2009. Seventy-one recommendations were made, and some key recommendations related to our industry are discussed here. Climate change has again dominated the media, with the United Nations Climate Change Conference held in Copenhagen in December 2009. In Queensland, the Government released a paper that presented a range of strategies and policies, building on a number of existing schemes and introducing new measures. Gas is identified as a key transitional fuel while low emission coal technology and emerging renewable energy sources are being developed. Greenhouse gas legislation is continuing to be developed across several states, but subordinate legislation is yet to be finalised. In Victoria, submissions on the Greenhouse Gas Geological Sequestration Regulations closed in October 2009, and the Greenhouse Gas Geological Sequestration Act 2008 came into effect on 1 December 2009. In March 2009, ten offshore acreage releases were made under the Commonwealth legislation; however, the closing date for submissions is dependent upon the development of the regulations. South Australia passed an Act amending the Petroleum and Geothermal Act 2000 on 1 October 2009 to allow geosequestration. A number of reviews of the regulatory framework or the administrative systems associated with the upstream oil and gas sector have been completed in the last decade. All these reviews make similar findings and recommendations, and most recently the Jones Report, tabled in Western Australian Parliament on 12 August 2009, found that most key recommendations from previous reports and reviews had not been addressed or properly implemented. There seems to be little point in undertaking regulatory and system reviews that consistently make similar findings, if these findings are never addressed. The hurdles to implementation of key recommendations need to be identified, so that progress can be made in improving the approvals processes for the industry, and improving the environmental outcomes.

Field trials of the use of hydrated bentonite for decommissioning oil and gas wells

2016 ◽  
Vol 56 (2) ◽  
pp. 561 ◽  
Author(s):  
Brian Towler ◽  
Mahshid Firouzi ◽  
Amin Mortezapour ◽  
Paul Hywel-Evans
Keyword(s):  
Coal Seam ◽  
Oil And Gas ◽  
Laboratory Data ◽  
Field Trials ◽  
Gas Wells ◽  
Coal Seam Gas ◽  
Water Wells ◽  
The Us ◽  
Oil And Gas Wells ◽  
The Many

Bentonite is widely used for plugging shallow water wells in the US. In the past 15 years Chevron has been plugging oil and gas wells with bentonite in the San Joaquin Basin in California, and has successfully plugged about 10,000 wells. In several previous publications the authors’ research team has reported laboratory data to predict pressure containment using bentonite to underpin the fundamentals for plugging both oil and gas wells. The authors propose bentonite as an alternative medium for decommissioning coal seam gas wells in Queensland. Gas producing companies in Queensland are proposing to drill and produce about 40,000 coal seam gas wells in the state, and all of these will have to be plugged eventually. Water wells are shallow and are usually plugged with coarse granulated bentonite that is simply poured down the hole and hydrated. The authors propose a process for compressing bentonite into cylinders of various shapes, which promises to improve the use of bentonite for plugging deeper wells. Oil and gas wells are presently plugged and abandoned with cement. Bentonite has a number of advantages when plugging oil and gas wells. It is cheaper and easier to deploy and it is more reliable than cement. In this extended abstract the application of bentonite for plugging conventional oil and gas and coal seam gas wells will be discussed. The many field trials will be reviewed and the fundamental theory for plugging wells with bentonite will be outlined.

From wells to decisions—data management for coal seam gas operators in Australia as compared to conventional oil and gas operators

2011 ◽  
Vol 51 (2) ◽  
pp. 716
Author(s):  
Peter Smith ◽  
Iain Paton
Keyword(s):  
Coal Seam ◽  
Data Management ◽  
Case Studies ◽  
Oil And Gas ◽  
Data Access ◽  
Oil And Gas Industry ◽  
Coal Seam Gas ◽  
Gas Industry ◽  
Innovative Solutions ◽  
Conventional Oil

The large number of wells associated with typical coal seam gas (CSG) developments in Australia has changed the paradigm for field management and optimisation. Real time data access, automation and optimisation—which have been previously considered luxuries in conventional resources—are key to the development and operation of fields, which can easily reach more than 1,000 wells. The particular issue in Australia of the shortage of skilled labour and operators has increased pressure to automate field operations. This extended abstract outlines established best practices for gathering the numerous data types associated with wells and surface equipment, and converting that data into information that can inform the decision processes of engineers and managers alike. There will be analysis made of the existing standard, tools, software and data management systems from the conventional oil and gas industry, as well as how some of these can be ported to the CSG fields. The need to define industry standards that are similar to those developed over many years in the conventional oil and gas industry will be discussed. Case studies from Australia and wider international CSG operations will highlight the innovative solutions that can be realised through an integrated project from downhole to office, and how commercial off the shelf solutions have advantages over customised one-off systems. Furthermore, case studies will be presented from both CSG and conventional fields on how these enabling technologies translate into increased production, efficiencies and lift optimisation and move towards the goal of allowing engineers to make informed decisions as quickly as possible. Unique aspects of CSG operations, which require similarly unique and innovative solutions, will be highlighted in contrast to conventional oil and gas.

Graded Proppant Injection into Coal Seam Gas and Shale Gas Reservoirs for Well Stimulation

2015 ◽  
Author(s):  
Alireza Keshavarz ◽  
Alexander Badalyan ◽  
Themis Carageorgos ◽  
Pavel Bedrikovetsky ◽  
Ray Johnson
Keyword(s):  
Coal Seam ◽  
Shale Gas ◽  
Coal Seam Gas ◽  
Gas Reservoirs ◽  
Well Stimulation ◽  
Shale Gas Reservoirs

Magnetotelluric monitoring of coal-seam gas and shale-gas resource development in Australia

2016 ◽  
Vol 35 (1) ◽  
pp. 64-70 ◽  
Author(s):  
Nigel Rees ◽  
Simon Carter ◽  
Graham Heinson ◽  
Lars Krieger ◽  
Dennis Conway ◽  
...  
Keyword(s):  
Coal Seam ◽  
Shale Gas ◽  
Resource Development ◽  
Coal Seam Gas

Production and development review 2007

2008 ◽  
Vol 48 (1) ◽  
pp. 423
Author(s):  
Jim Willetts
Keyword(s):  
Coal Seam ◽  
Oil And Gas ◽  
Oil Production ◽  
Gas Production ◽  
Project Delivery ◽  
Coal Seam Gas ◽  
Supply Source ◽  
Production Growth ◽  
Near Term ◽  
Skills Shortages

Australian petroleum production was close to record levels in 2007 with higher oil production and expansion of domestic gas, LNG and coal seam gas production. Growth in coal seam gas production has reached the point where it is not only providing a significant supply source for domestic gas and power station projects, but is proposed as the source of supply to no less than four potential LNG export plants in Queensland. Five new oil and gas developments came on stream during the year. Four final investment decisions were taken on major projects, the largest being the Pluto project in the Carnarvon Basin. The pipeline of committed and potential projects now includes about 25 significant petroleum projects with a combined value of over $100 billion. Together these have the potential to significantly increase Australian production in the next five to ten years, primarily through growing gas production. In the near term significant new oil projects carry the prospect of higher oil production in 2008. Cost estimates for new projects continued to escalate sharply and skills shortages in all parts of the project delivery chain threaten the ability to deliver all of the projects as contemplated.

Why the wait? Shale gas exploration review and look ahead

2015 ◽  
Vol 55 (2) ◽  
pp. 404
Author(s):  
David Close
Keyword(s):  
Shale Gas ◽  
Oil And Gas ◽  
Sedimentary Basins ◽  
Energy Information Administration ◽  
Development Projects ◽  
Oil And Gas Development ◽  
Look Ahead ◽  
Development Teams ◽  
Asset Development ◽  
Energy Information

Despite unconventional targets being recognised across many Australian sedimentary basins and the Energy Information Administration (EIA), estimating a technically recoverable shale gas resource of >400 tcf in Australia, there have been no definitive tests that prove that any of these potential plays will flow gas at commercial rates. There has, however, been a number of technical successes reported from both shale gas and basin centred gas plays. This extended abstract reviews select plays from both frontier and mature basins across Australia, including basins where Origin is actively exploring or appraising unconventional gas plays—the Perth, Cooper and Beetaloo basins. The technical challenges vary from play to play, but many of the above ground challenges are not play specific. To advance the industry, Origin and other companies will have to demonstrate a resource sufficiency that is economic in a high cost environment like Australia, while maintaining a positive relationship with communities. In its expansion into the NT, through its interest in the Beetaloo Basin, Origin has the benefit of 20 years' experience dealing with complex stakeholders and environmental challenges through its CSG development projects in Queensland. This experience is invaluable in advising best practices for engaging with local communities, landholders, traditional owners, and regulatory and government bodies. For the technically-minded asset development teams charged with exploring unconventional plays in frontier basins, where stakeholders are unfamiliar with oil and gas development projects, new skills are required that need deep organisational support.

Magnetotelluric monitoring of coal seam gas depressurisation

2015 ◽  
Vol 55 (2) ◽  
pp. 466
Author(s):  
Nigel Rees ◽  
Graham Heinson ◽  
Lars Krieger ◽  
Goran Boren ◽  
Dennis Conway ◽  
...  
Keyword(s):  
Coal Seam ◽  
Test Site ◽  
Coal Seam Gas ◽  
Subsurface Environment ◽  
Aquifer Systems ◽  
Conductivity Structure ◽  
Electric And Magnetic Fields ◽  
New Processing

The depressurisation of coal seam gas (CSG) formations causes in-situ fluids to migrate through pores and fractures in the earth. The removal of large volumes of water from coal seams has the potential to affect water table levels and groundwater flow in surrounding aquifer systems. Magnetotellurics (MT) is a passive electromagnetic technique that uses the natural fluctuations of electric and magnetic fields at the Earth’s surface to determine the Earth’s conductivity structure. The bulk movement of fluids during CSG depressurisation causes a conductivity change in the subsurface and this change can be monitored using MT. An electromagnetic survey was conducted at a CSG production scientific test site. Electric and magnetic field instruments were deployed, measuring continuously at 651 Hz across three months. New processing software was developed to generate MT responses in the bandwidth of 100–0.1 Hz across the experiment. The theory of monitoring subsurface fluid movement using MT is presented, as well as instrumentation and a case study to demonstrate the potential of the magnetotelluric method. Results from this approach can provide an inexpensive means of monitoring CSG depressurisation, as well as an improved understanding of the potential impacts on the subsurface environment during CSG production.

Analysis of physical, chemical and mechanical rock properties for effective multiscale modelling of reservoir processes and systems

2020 ◽  
Author(s):  
Artyom Myasnikov
Keyword(s):  
Phase Equilibrium ◽  
Oil And Gas ◽  
Solid Phase ◽  
Spatial Scales ◽  
Chemical Properties ◽  
Sedimentary Basins ◽  
Rock Properties ◽  
Correct Selection ◽  
First Case ◽  
Thermodynamic Potentials

<p>Reservoir processes and systems cover wide spatial range of scales from nanoscale physical and chemical transport in the pore to fluid migration in reservoir systems during formation of sedimentary basins. Thorough analysis of physico-chemical properties on each scale allows us to conclude that for adequate consideration of the majority of multiscale features it is necessary to solve a finite number of fundamental problems, which include:</p><p>- creation and development of a new concept of Representative Elementary Volume (REV), which takes into account the specificity of multiporous and multi-permeable multiscale cracked environment;</p><p>- development of a new approach to solving the problem on phase equilibrium of fluids and solid phase in pores and micropores;</p><p>- nano-chemical-mechanical determination of quantitative strength characteristics of rocks due to phase transformations of various inhomogeneities that make up a given rock.</p><p> </p><p>These problems are interrelated [1,2]. The REV problem is of primary importance, both from conceptual and practical points of view.  Success of modeling depends on correct selection of REV for different spatial scales. For example, instead of development of double porosity models for fractured rocks, it is possible to grind REV up to its homogeneity in relation to heterogeneities of interest. We support and develop the second approach. We believe, that the future belongs to the ability to describe multiscale processes using the same set of defining relations, in which the coefficients depend on the selected scale. When choosing the second approach, we put great attention to the development of new approaches to solving the problem of phase equilibrium of fluids and solid phase in pores and micro-nanopores. And, if in the first case we are talking about methods based on thermodynamically consistent systems of equations and numerical methods, intensively developed at present and based on minimization of basic thermodynamic potentials, for nanopores there is still a question of expanding the concept of thermodynamic equilibrium, where in the pore may be no more than 1-3-10 molecules [3].</p><p> </p><p>Experiment on the nano-scale acquires a special meaning. Filtration, rock elastic and strength parameters play a desizive role for uch formations. And they may be changed due to field dtvelopment.  Such works are currently in progress, however, we believe they are of an exquisitely fundamental nature and are still far from practical oil and gas applications.</p><p> </p><p> [1].Мясников А.В. О моделировании экологически безопасной закачки флюидов в пласт // EAGE/SPE Joint Workshop 2015. Exploration of shale oil resources and reserves</p><p>[2]Yarushina V., Podladchikov Yu (De) compacion of porous viscoelastoplastic media, JGR, 2015, 120(6), 4146.</p><p>[3].Stroev N., Myasnikov A.V. Review of Current Results in Computational Studies of Hydrocarbon Phase and Transport Properties in Nanoporous Structures AIP Conference Proceedings, 2017, 1909, 020213-1–020213-6</p>

scholarly journals Defining Uncertainty: Comparing Resource/Reserve Classification Systems for Coal and Coal Seam Gas

Energies ◽  
2021 ◽  
Vol 14 (19) ◽  
pp. 6245
Author(s):  
Tim Moore ◽  
Mike Friederich
Keyword(s):  
Coal Seam ◽  
Oil And Gas ◽  
Mineral Resources ◽  
Classification Systems ◽  
Coal Seam Gas ◽  
Mining Investment ◽  
Petroleum Resource ◽  
High Level ◽  
Chinese Standard

Transparent, objective, and repeatable resource assessments should be the goal of companies, investors, and regulators. Different types of resources, however, may require different approaches for their quantification. In particular, coal can be treated both as a solid resource (and thus be mined) as well as a reservoir for gas (which is extracted). In coal mining, investment decisions are made based on a high level of data and establishment of seam continuity and character. The Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves (the JORC Code) allows deposits to be characterised based on the level of geological and commercial certainty. Similarly, the guidelines of the Petroleum Resource Management System (PRMS) can be applied to coal seam gas (CSG) deposits to define the uncertainty and chance of commercialisation. Although coal and CSG represent two very different states of resources (i.e., solid vs. gaseous), their categorisation in the JORC Code and PRMS is remarkably similar at a high level. Both classifications have two major divisions: resource vs. reserve. Generally, in either system, resources are considered to have potential for eventual commercial production, but this has not yet been confirmed. Reserves in either system are considered commercial, but uncertainty is still denoted through different subdivisions. Other classification systems that can be applied to CSG also exist, for example the Canadian Oil and Gas Evaluation Handbook (COGEH) and the Chinese Standard (DZ/T 0216-2020) and both have similar high-level divisions to the JORC Code and PRMS. A hypothetical case study of a single area using the JORC Code to classify the coal and PRMS for the gas showed that the two methodologies will have overlapping, though not necessarily aligned, resource and reserve categories.

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