Unit information: Advanced aqueous geochemistry in 2012/13

Unit name	Advanced aqueous geochemistry
Unit code	EASC30042
Credit points	10
Level of study	H/6
Teaching block(s)	Teaching Block 1A (weeks 1 - 6)
Unit director	Professor. Sherman
Open unit status	Not open
Pre-requisites	Successful completion of years 1 and 2 of either the Environmental Geoscience or Geology degree programme curriculum
Co-requisites	n/a
School/department	School of Earth Sciences
Faculty	Faculty of Science

Description including Unit Aims

Thermodynamics of aqueous solutions and mineral-solution equilibira that control the geochemistry of aquatic environments. Application will include the fate of environmental contaminants, C02 sequestration, formation of ore deposits and chemistry of groundwater.

Intended Learning Outcomes

• Understand the role of mineral dissolution/precipitation, ion exchange, sorption and complexation reactions in determining the chemistry of the oceans, rivers and groundwater.

• Be able to model the thermodynamics and kinetics of complex aquatic systems using a standard computer code (PHREEQC).

• Understand how transport processes (advection and diffusion) couple with kinetics to cause departures from equilibrium in real systems.

Assessment Information

Assessment:

The unit mark will be based on the coursework (50%) and a final exam (50%). The exam will assess your understanding of the fundamental concepts applied in the unit

Feedback:

Feedback will be provided on the practical write-ups. A review session prior to the exam will also be provided.

Reading and References

Classic Papers:

Helgeson HC, DH Kirkham and GC Flowers (1981) Theoretical prediction of the thermodynamic behavior of aqueous electrolytes at high pressures and temperatures: IV. Calculation of activity coefficients, osmotic coefficients, and apparent molal and standard and relative partial molal properties to 600°C and 5 kb Am. J. Sci. 281:1249-1516; Sverjensky DA, Shock EL, Helgeson HC (1997) Prediction of the thermodynamic properties of aqueous metal complexes to 1000 degrees C and 5 kb Geochimica et Cosmochimica Acta 61: 1359-1412; Shock EL, Helgeson HC (1989) Calculation of the thermodynamic and transport properties of aqueous species at high pressures and temperatures--correlation algorithms for ionic species and equation of state predictions to 5 kb and 1000 C. Geochimica et Cosmochimica Acta 52: 2009-2036; Helgeson HC, Garrels RM, Mackenzie FT (1968) Evalulation of irreversible reactions in geochemical processes involving minerals and aqueous solutions 2. Applications. Geochimica et Cosmochimica Acta 33:455; Garrels RM, and Mackenzie FT (1967) Origin of the chemical composition of springs and lakes, in Equilibrium concepts in natural water systems: American Chemical Society, Advances in Chemistry Series 67:222-242; Recent Applications of Geochemical Modelling: Brown JG, Glynn PD (2003) Kinetic dissolution of carbonates and Mn oxides in acidic water: measurement of in situ field rates and reactive transport modeling Applied Geochemistry 18,1225-1239; Tonkin, JW, Balistrieri LS, and Murray JW (2002) Modeling Metal Removal onto Natural Particles Formed during Mixing of Acid Rock Drainage with Ambient Surface Water Environ. Sci. Technol., 36, 484-492; Timms WA, Hendry MJ (2007) Quantifying the impact of cation exchange on long-term solute transport in a clay-rich aquitard, Journal of Hydrology 332, 110-122; Raffensperger JP, Garven G (1995) The formation of unconformity-type uranium ore-deposits. 2. Coupled hydrochemical modeling. American Journal of Science 295 (6): 639-696; Steefel CI, DePaulo DJ, and PC Lichtner (2005) Reactive transport modeling: An essential tool and a new research approach for the Earth sciences Earth and Planetary Science Letters, 240, 539-558