A

Absorption

Chemical or physical take-up of molecules into the bulk of a solid or liquid, forming either a solution or compound.

Adsorption

The uptake of molecules on the surface of a solid or a liquid.

Amine

Organic chemical compound containing one or more nitrogens in -NH2, -NH or -N groups.

Amino acid

Any of a group of organic molecules that consist of a basic amino group (-NH2), an acidic carboxyl group (-COOH), and a side chain which is unique to each amino acid.

B

Basin

A geological region with strata dipping towards a common axis or centre.

Buttress -1 gas

Buttress -1 is gas sourced from the Butress-1 well owned by CO2CRC and located in Nirranda South. The Gas is composed of 18.91mol% methane, 78.66mol% carbon dioxide, 2.43 mol% of other hydrocarbons heavier than methane plus nitrogen.

C

Caprock

Rock of very low permeability that acts as an upper seal to prevent fluid flow out of a reservoir.

Carbon dioxide (CO2)

Carbon dioxide occurs naturally in the atmosphere, is exhaled by humans and other animals and is used by plants in photosynthesis. Growing plants and the oceans act as carbon sinks, taking carbon dioxide from the atmosphere and storing the carbon. As plant material decomposes, the carbon is released back into the atmosphere, largely as carbon dioxide. Burning fossil fuels, land clearing and other activities of modern industrial society have caused the concentration of carbon dioxide in the atmosphere to climb from about 280 parts per billion to 380 parts per billion, causing warming and other climate changes.

Carbonate

Those minerals containing the carbonate ion, CO32-. These include calcite, dolomite, and limestone.

Covalent Bond

Covalent Bond is a chemical bond that involves sharing a pair of electrons between atoms in a molecule.

Cryogenic

Pertaining to low temperatures.

D

Distributed acoustic sensing (DAS)

Distributed acoustic sensing systems are fiber optic based optoelectronic instruments which measure acoustic interactions along the length of a fiber optic sensing cable. DAS can be used to measure seismic response.

G

Geosequestration

Carbon Dioxide is captured, compressed and injected into deep geological formations.

Geophone

A device that converts ground movement (velocity) into voltage. The deviation of this measured voltage from the base line is called the seismic response.

Giga

Prefix meaning one billion (109).

I

IPCC

Intergovernmental Panel on Climate Change

IGCC

Integrated Gasification Combined Cycle

Ion

An atom or molecule that has acquired a charge by either gaining or losing electrons.

Ionic liquid

A liquid that is essentially ions.

Intergovernmental Panel on Climate Change (IPCC)

Established in 1988 by the World Meteorological Organization and the United Nations Environment Programme to assess on a comprehensive, objective, open and transparent basis the scientific, technical and socio-economic information relevant to understanding the scientific basis of risk of human-induced climate change, its potential impacts and options for adaptation and mitigation. The IPCC does not carry out research nor does it monitor climate related data or other relevant parameters. It bases its assessment mainly on peer reviewed and published scientific/technical literature.

Integrated Gasification Combined Cycle (IGCC)

A process where fossil fuel is not combusted but is reacted at high pressure and temperature to form a synthesis gas, which is further reacted with water, to produce carbon dioxide (which can be captured) and hydrogen (which is combusted for energy).

Isopach Map

A map that is drawn with contours that connect points of equal thickness of geological stratum.

K

Kyoto Protocol

An international agreement which seeks to reduce annual greenhouse gas emissions by developed nations in its first commitment period, 2008-2012, to 5 per cent less than 1990 emissions. It seeks to achieve this by imposing mandatory emissions targets on developed nations that ratify the Protocol.

M

Mega

Prefix meaning one million (106).

Membrane

Material that selectively separates the components of a fluid mixture by preferentially separating molecules from one component from other components.

Mineral trapping

When dissolved CO2 reacts with the reservoir rock, carbonate minerals can form and precipitate, trapping CO2 in the most stable form. While there is some reaction in the early years of storage, the time line for this trapping mechanism is over thousands of years. The potential for reaction to form these minerals depends on the composition of the reservoir rock (eg the presence of aluminosilicates), the temperature and pressure of the rock, the chemical composition of the water, the water/rock contact area and the rate of fluid flow through the rock. Mineral trapping is the most secure stage of CO2 trapping.

O

Oxyfiring (also oxyfuel)

Burning of fuel in an artificially created atmosphere of oxygen instead of air, resulting in flue gases with high concentrations of carbon dioxide.

Oxyfuel (also oxyfiring)

Burning of fuel in an artificially created atmosphere of oxygen instead of air, resulting in flue gases with high concentrations of carbon dioxide.

P

PCC

Post-combustion capture. The capture of carbon dioxide (usually involving separation of carbondioxide from other flue gases) after fossil fuel has been combusted.

Petrophysical

Petrophysical properties of rocks include properties that pertain to fluid behavior within the rock, such as porosity, capillary pressure, permeabilities or saturations.

Post-combustion capture (PCC)

The capture of carbon dioxide (usually involving separation of carbondioxide from other flue gases) after fossil fuel has been combusted.

Pre-combustion capture

The capture of carbon dioxide before the combustion of fuel. This could be done through Integrated Gasification Combined Cycle, where the fossil fuel is not combusted but reacted at high pressure and temperature to form a synthesis gas, which is further reacted with water, to produce carbon dioxide (which is captured) and hydrogen (which is combusted for energy).

R

Residual trapping

Residual gas trapping occurs when a small amount of CO2 becomes disconnected or ‘snaps off’ from the CO2 plume as the CO2 moves through the porous rock. The CO2 is stored in the pores in tiny bubbles, trapped by surface tension. The CO2 can’t move out of the pore space and remains fixed underground.

S

Saline formation

Sediment or rock body containing brackish water or brine.

Sedimentary basin

Natural large-scale depression in the earth’s surface that is filled with sediments.

Seismic

A method of exploring the underlying strata of the earth, in which shocks are created, the resulting vibrations providing geological information

Surface orbital vibrator

Surface orbital vibrator is a motor that spins an unbalanced weight mounted on a reinforced concrete block which is buried in the ground. It is able to create low-frequency vibrations into the earth that can be used as a source in seismic measurement.

Structural trapping

CO2 is trapped by a seal rock above the formation and a sealing fault at the side of the formation.

Solubility (also known as dissolution) trapping

This trapping mechanism refers to the portion of CO2 that is dissolved in the formation water. Once the CO2 dissolves, the water becomes denser, sinks towards the bottom of the formation and is more securely stored

Supercritical state

Carbon dioxide (or any substance) is said to be in a supercritical state when its temperature and pressure are above its critical point. The critical point is the highest temperature and pressure at which it can exist as a gas and liquid in equilibrium. In its supercritical state, a substance shows properties of both liquids and gases, expanding to fill its container like a gas, but with the density of a liquid. The critical point for carbon dioxide occurs at a pressure of 73.8 bar (73 atm) and a temperature of 31.1°C.

SCAL

Special Core Analysis.

U

UNFCCC

United Nations Framework Convention on Climate Change.

United Nations Framework Convention on Climate Change (UNFCCC)

Sets an overall framework for intergovernmental efforts to tackle the challenge posed by climate change. The Convention, which entered into force in 1994, enjoys almost universal global membership, with 189 countries having ratified it.

V

Viscous Fingering

Viscous Fingering is the formation of patterns in a morphologically unstable interface between two fluids in a porous medium.

Vertical Seismic Profiling (VSP)

Vertical Seismic Profiling (VSP) is a geophysical technique of seismic measurement where the seismic receivers and sometimes also the seismic source are located in a borehole.

Vibroseis trucks

Vibroseis trucks or a Vibe is a seismic vibrator mounted on a truck that is capable of creating low-frequency vibrations into the earth. It is one of a number of seismic sources used in reflection seismology.

Z

Zeolite

A mineral with a micro-porous structure.