Students2006

Tara Clark

PhD Candidate

Degree: BSc Hons (Marine Science & Management) University of New England
Supervisor/s: Jian-xin Zhao, John Pandolfi (UQ), Terry Done (AIMS)

Rm 210B, Richards Building
Ph: 3346 7382
Email: Tara Clark

Project Title:
Historical mortality events of inshore reef coral communities within the Great Barrier Reef since European settlement

While the GBR is considered to be one of the least degraded coral reefs in the world, increasing evidence suggests that this may not be the case with a loss of hard coral cover being observed on inshore reefs and an increase in macroalgae. With detailed knowledge of the GBR limited to the past 25yrs, little is known of the past changes in coral communities since European settlement and the onset of anthropogenic disturbance.
This research will use highly precise uranium-series (U-series) thermal ionisation mass spectrometry (TIMS) dating of dead Acropora coral rubble (death assemblage) and massive Porites from inshore reef environments influenced by terrestrial runoff and high sea surface temperatures, to provide an accurate chronology on the timing of historical mortality events.
Furthermore, an analysis of various environmental proxies within massive coral skeletons will help to determine the possible causes for mortality in adjacent communities.
This will provide a means to better understand changes in near shore coral communities and help to elucidate natural versus anthropogenic disturbances impacting these environments so that management can be directed towards ameliorating primary threats

Recent publications and abstracts:

Clark, T.R., Roff, G., Zhao, J-x., Pandolfi, J.M., and Done, T.J. In Press. Dating and mapping historical changes in GBR coral communities. Proceedings of the 2008 Conference of the Marine and Tropical Sciences Research Facility, Cairns. 28 April - 1 May.

Clark, T.R., Roff, G., Zhao, J-x., Pandolfi, J.M., and Done, T.J. 2008. Timing of hard coral loss since European settlement: Pelorus Reef, inshore Great Barrier Reef. In: 4^th AINSE Quaternary Dating workshop, 26-27 March, 2008.

Matt Davies

PhD Candidate

Degree: BSc Hons (1st class, Mathematics) Queensland University of Technology
Supervisor/s: Hans Muhlhaus, Lutz Gros

Rm 803, Sir James Foots (47a) Building
Ph: 334 64090
Email: Matt Davies

Project Title:
Computational Schemes in Nonlinear Solid Geodynamics

The solid geophysical flow of constituent planetary processes occurring at multiple spatial and temporal scales exhibit nonlinear viscoplastic-elastic effects. For this reason, the incorporation of these non-Newtonian effects into a single constitutive relationship allows, in principle, the modeling of phenomena such as faulting, shearing, magmatic flow, subduction, convection and even plate tectonics in a unified manner (Mühlhaus and Regenauer-Lieb, 2005). Through this unified model, the different components of mechanical flow incorporating Newtonian, power-law, plastic and elastic flow components are represented as coincident features of a single physical model. In this regard, we consider the steady (Boussinesq) Stokes equations as applied to solid state geophysics which are given in terms of velocity and pressure by:

in conjunction with the incompressibility constraint:

These equations are completed with an initial condition for the velocity:

and a "no flow" boundary condition:

The coincident features of this model are then determined by way of the composite deformation rate given as follows under the Maxwell constitutive model:

In the case of solid geophysical convection, the mechanical flow components are then controlled by the strong exponential temperature and pressure dependence of the composite viscosity.
A significant computational difficulty arises from the solution of these equations in this context. In particular, the difficulty is associated with:
" the incompressible treatment
" the strong nonlinearity and contrast of the viscosity
This project seeks to address these difficulties and develop an improved high-level solution framework and computational solution schemes that can be applied to transient nonlinear solid state geodynamics flows.

Recent publications and abstracts:

Gross, L., Cochrane, P., Davies, M., Mühlhaus, H., and Smilie, J. 2005. A Python-Based Programming Environment For Solving Coupled Partial Differential Equations. Computational Methods for Coupled Problems in Science and Engineering.

Gross, L., Cochrane, P., Davies, M., Mühlhaus, H., and Smillie, J. 2005. Escript: Numerical Modelling With Python. Proceedings Australian Partnership For Advanced Computing (APAC) Conference.

Mühlhaus, H., Moresi, L., Davies, M., and Gottschaldt, K. 2005. Towards a Unified Model for the Dynamics of Planets. Computational Methods for Coupled Problems in Science and Engineering.

Mühlhaus, H., Davies, M., Gross, L., and Moresi, L. 2005. Non-Newtonian Effects in Simple Models of Mantle Convection. Proceedings Third MIT Conference on Computational Fluid and Solid Mechanics.

Davies, M., Gross, L., and Mühlhaus, H. 2004. Scripting High Performance Earth Systems Simulations on the SGI Altix 3700. Proceedings of the 7th International Conference on High Performance Computing and Grid in the Asia Pacific Region.

Davies, M., Mühlhaus, H., and Gross, L. 2004. Thermal Effects in the Evolution of Initially Layered Mantle Material. Pure Appl. Geophys.

Davies, M., Mühlhaus, H., and Gross, L. 2004. The Rapid Development of High Performance Numerical Models in Mantle Convection. APEC Cooperation for Earthquake Simulation (ACES) 4th ACES Workshop Proceedings, Book of Extended Abstracts.

Gross, L., Davies, M., and Gerschwitz, J. 2004. A High-Level Programming Language for Modeling the Earth. Pure Appl. Geophys.

Gross, L., Davies, M., and Gerschwitz, J. 2004. A High-Level Programming Language for Modeling the Earth. APEC Cooperation for Earthquake Simulation (ACES) 4th ACES Workshop Proceedings, Book of Extended Abstracts.

Mühlhaus, H., Davies, M., Gross, L., and Moresi, L. 2004. Elasticity, Yielding and Episodicity in Simple Models of Mantle Convection. Pure Appl. Geophys.

Grant Dawson

PhD Candidate

Degree: BSc(Chemistry), BSc Hons(Earth Sciences) University of Queensland
Supervisor/s: Sue Golding, Joan Esterle

Rm 233 Steele Building
Ph: 336 54787
Email: Grant Dawson

Project Title:
Flue Gas and CO₂ Geosequestration in Surat and Bowen Basin Coals

The most feasible way for Australia to significantly reduce emissions, given current technological and economical restraints, is to sequester emissions from large point sources (e.g. power stations) underground. Deep un-minable coal seams are an abundant geological medium, close to emission point sources, in both Queensland and New South Wales that could potentially store the bulk of these States’ carbon emissions. Sequestration in coal has additional environmental and economical benefits in that the sequestered carbon dioxide (CO₂) will displace natural gas. This natural gas could be sold to offset the cost of sequestration, and burning natural gas produces ~50% less carbon emissions than coal for a given amount of energy. Our project will investigate the geochemical reactions that occur at depth between coal and a range of fluids, from flue gas (nitrogen + water + CO₂ and others) to pure CO₂. If injection of flue gas is found to be a more efficient means of sequestration than injection of pure CO₂, this will eliminate the need to isolate CO₂ from bulk power station emissions (flue gas) and thus significantly lower the cost of sequestration.

Recent publications and abstracts:

Dawson, G.K.W., and Esterle, J. 2008. Rank and Type Controls on Coal Cleat spacing and Porosity (in prep).

Zarah Heyworth

PhD Candidate

Degree: BSc Adv Hons (Geosciences) Monash University
Supervisor/s: Kurt Knesel, Massimo Gasparon, Paulo Vasconcelos, Richard Arculus (ANU)

Rm 130, Richards Building
Ph: 334 69782
Email: Zarah Heyworth

Project Title:
4D picture of mantle heterogeneity in subduction zones: a geochemical and geochronological study of submarine volcanoes and spreading centres, Vanuatu.

Subduction zones are sites of recycling of oceanic lithosphere, chemical modification of the upper mantle, magma production and crustal growth. One approach to the study of these dynamic systems has been through geochemical examination of arc volcanoes. Although the compositions of arc magmas have provided important first-order insights into subduction zone processes, a more detailed understanding is hampered by a scarcity of undifferentiated magmas derived directly from subduction-modified mantle wedge. This project will investigate how subduction and backarc spreading influence the time-dependent composition and flow patterns of the upper mantle so as to provide new insights into the structure and composition of the mantle wedge and the processes that modify the composition of mantle through time.

Recent publications and abstracts:

Heyworth, Z., Turner, S.P., Schaefer, B.F., Wood, B., George, R.M.M., Berlo, K., Cunningham, H., Price, R.C., Cook, C. and Gamble, J.A. ²³⁸U-²³⁰Th-²²⁶Ra-²¹⁰Pb constraints on the time scales of high-Mg andesite evolution at White Island, New Zealand. Chemical Geology, vol. 243, 105-121.

Heyworth, Z., Schaefer, B.F., and Nicholls, I.A. 2005. Intraplate hypersthene-bearing trachyandesites: Evidence for multiple magma sources in the Newer Volcanic Province, Australia. Geological Society of Australia Abstracts, vol. 80, 12.

Heyworth, Z., George, R.M., Schaefer, B.F., and Turner, S.P. 2005. Insights into magma generation and evolution at White Island, New Zealand, from U-series disequilibria. Geological Society of Australia Abstracts, vol. 80, 24.

Heyworth, Z., George, R.M., Schaefer, B.F., and Turner, S.P. 2005. Magma generation and evolution at White Island, New Zealand. Geological Society of Australia Abstracts, vol. 76, 67.

Heyworth, Z., Nicholls, I.A., and Schaefer, B.F. 2005. Intraplate hypersthene-bearing trachyandesites: Evidence for multiple magma sources in the Newer Volcanic Province, Australia. Geochimica et Cosmochimica Acta, vol. 69, 855.

Emma Kinnon

MPhil

Degree: BE (Chemical) The University of Queensland

Supervisor/s: Joan Esterle , Sue Golding

Rm 233, Steele Building
Ph: 336 54787
Email: Emma Kinnon

Project Title:
Geological controls on gas flow pathways in coal seams.

The aim of the study is gain a better understanding of natural and induced changes in reservoir pressure, water and gas migration in coal seam reservoirs over time during production at the field scale. Production across the chosen gas field of study has varied considerably, both within and between reservoir seams due to drilling performance and geology. Understanding this variability in past reservoir behaviour, in particular the role of geology and coal seam character leads to better modelling and prediction of future reservoir behaviour.
If reservoir behaviour during commercial gas extraction can be understood, then better scale-up models for injection, enhanced residual gas recovery and potential sequestration of CO₂ can be developed.

Recent publications and abstracts:

Guia Morelli

PhD Candidate

Degree: BSc and MSc University of Florence (Italy)
Supervisor/s: Dr Massimo Gasparon & Dr Catherine Lovelock

Rm 118, Richards Building
Ph: 336 57140
Email: Guia Morelli

Project Title:
Human impact on estuarine environments - an example from Moreton Bay, southeast Queensland

The project will provide new knowledge towards understanding of the geological history of Moreton Bay. Moreton Bay is one of Australia's largest estuarine systems and could be a good model to understand links between terrestrial and marine ecosystems since European colonization. The currently available evidence suggests Moreton Bay has been drastically changed since European arrival, with accelerated rates of sedimentation and delivery of carbon and nutrients from the terrestrial to the marine environment.

By taking cores and using stratigraphic techniques and stable isotope analysis I will be able to investigate the history and the extent of spatial variation in deposition of terrestrial material across different sites in the bay as mangroves, salt marsh and supra-tidal salt flats. Sedimentological analysis (Total Carbon (TC), Total Organic Carbon (TOC), grain size, mineralogical composition, trace metal concentration, and Pb isotopes) of sediment cores will define variations in type and in the rate of sediment supplied to the Bay as a function of time. This set of data will provide information on the paleo-environmental evolution of the Moreton Bay area, with emphasis on anthropogenic input during the last 200 years.

Recent publications and abstracts:

Thomas E., Roehl U., Monechi S., Westerhold T.,Balestra B. and Morelli G. 2006. An Early Eocene hypertermal event at~52,5 MA. Climate & Biota of the Early Paleogene, Bilbao.

Galeotti S., Heal S., Kaminski M., Lanci L, Monechi S, Morelli G. and Zachos J.C ., 2006. The Elmo event in the classical Tethian setting of the Contessa Road section (Gubbio, Central Italy). Climate & Biota of the Early Paleogene, Bilbao.

Morelli G., Pandeli E., Principi G., 2004. Stratigraphic and tectono-metamorphic evolution of the alpine para-autochton units between Popolasca and Ponte di Castirla (North-Central Corsica). 32nd IGC, Florence 2004.

Josh Moulds

PhD Candidate

Degree: Degree: BAppSc Hons (1st Class), Queensland University of Technology

Supervisor/s: Gilbert Price, Jian-xin Zhao

Rm 204, Richards Building
Ph: 336 52176
Email: Josh Moulds

Project Title:
Palaeoclimatic and palaeoecological reconstructions of Quaternary faunal evolution in eastern Australia

The abundance of vertebrate remains in faunal assemblages from cave deposits allows for the reconstruction of ancient ecosystems. Interpretations of past habitat type on the basis of ecological make-up can reveal broad palaeoclimatic inferences at a local scale.
The association of vertebrate deposits with contemporaneous karst formation (speleothems) in caves enables precision age determination of the fauna records and provides a means of direct correlation of ecology to climate. Construction of a geochronological framework via U-series dating methods will complement stable isotope (C-O-Sr) analysis allow palaeoclimatic records of central Queensland to be established.
This study will target such vertebrate-speleothem associations from caves in the Mt. Etna area of Rockhampton, central Queensland, and will build upon previous work in the area which has established a turnover from rainforest- to arid-adapted species in reaction to middle-Pleistocene aridification of the central coast.
My research will also attempt to test the applicability of isotope dating methodologies to an array of carbonate mineral and skeletal material from cave deposits.
In this way, a better understanding of the relationship between faunal succession and changes in climate helps to address key unresolved issues of Quaternary vertebrate evolution on continental Australia. The recognition of evolutionary and ecological responses to climate has the added benefit of identifying potentially vulnerable groups of endemic species.
In the face of modern climate change, recognition of such trends will lend insight into organizing better conservation strategies for endangered vertebrate communities.

Recent publications and abstracts:

Moulds, J.J., and Webb, G. E. 2008. Trace element geochemistry of Neoproterozoic stromatolites: a tool for interpreting accretionary processes. Australian Earth Sciences Convention 2008, (submitted).

Moulds, J.J., and Webb, G. E. 2008. Geochemistry of Bioavailable Elements in Australian Neoproterozoic Stromatolites. (in prep.).

Roshni Narayan

PhD Candidate

Degree:
MSc in Earth Sciences, University of Victoria, Victoria, British Columbia, Canada
BSc in Zoology, University of Alberta, Edmonton, Alberta, Canada
Supervisor/s: Dr. John Pandolfi, David Neil, Jian-Xin Zhao

Rm 260, Steele Building
Ph: 336 52130
Email: Roshni Narayan

Project Title:
Historical (Holocene) and modern foraminiferal assemblages of Moreton Bay: Temporal, spatial distributions, natural vs. anthropogenic influences and implications for coral communities

I'm interested in foraminiferal studies of Moreton Bay. Since European colonisation over the past 200 years, coastal areas have undergone deterioration and the coral communities in the Bay have undergone significant faunal changes overtime. The nature and timing of these faunal changes is uncertain and essential in furthering our understanding of why these faunal transitions occurred and what the significance of natural (long-term) versus anthropogenic (short-term) influences are on regional coral communities. Living, sub-modern (since European colonization) and fossil (Holocene) foramininferal assemblages can will be studied to provide clues to the questions of when, how and why historical faunal changes occurred and a clearer picture of what the pre-impact environmental conditions were like in the Bay.

Recent publications and abstracts:

Johns, M.J., Barnes, C.R., Narayan, Y.R. and Trotter, J.A. In Press. New interpretation of the Crescent Terrane and geological evolution of the Tofino Basin, British Columbia. Bulletin of Canadian Petroleum Geology.

Johns, M.J., Barnes, C.R. and Narayan, Y.R. 2006. Cenozoic ichthyolith biostratigraphy: Tofino Basin, British Columbia. Canadian Journal of Earth Sciences, vol. 43(2), 177-204.

Johns, M.J., Barnes, C.R. and Narayan, Y.R. 2005. Catalogue of Cenozoic ichthyoliths from the Tofino Basin and western Vancouver Island, British Columbia, Canada. Palaeontologia Electronica, vol. 8.2.29A.

Narayan, Y.R., Barnes, C.R., and Johns, M.J. 2005. Taxonomy and biostratigraphy of Cenozoic foraminifers from Shell Canada wells, Tofino Basin, offshore Vancouver Island, British Columbia. Micropaleontology, vol. 51(2), 101-167.

Ai Duc Nguyen

PhD Candidate

Degree: BSc Hons, (Geology) Hochiminh University of Natural Sciences, Vietnam. 1998
MPhil., (Earth Sciences) The University of Queensland, Australia. 2007
Supervisor/s: Dr Jian-xin Zhao, Dr. Massimo Gasparon, Dr Kefu Yu

Rm 233, Steele Building
Ph: 336 54787
Email: Ai Duc Nguyen

Project Title:
Climatic and environmental reconstruction based on reef corals from the Vietnamese coast of the South China Sea

Globally climatic and environmental changes have been a controversial issue in recent years, especially following the recognition that eustatic sea level rise due to global warming can damage human beings. The interpretations of future climatic variability and environmental change require long-term records of climatic and environmental data. It is challenging to obtain such data because instrumental records only offer relatively recent data, typically less than 100 years from present. Fortunately, the landmark discovery of climatic and environmental-dependent proxy archives such as lake and ocean sediments, wind-blown deposits, ice cores, tree rings, speleothems (caves) and corals, and the recent breakthrough of very precise analytical techniques have helped scientists to rebuild the climatic variation and environmental change in a long timescale (back to hundreds of thousand years). This PhD project was proposed to reconstruct the variability of climate and environment back to the Holocene (10,000 years BP) based on dead corals on different sea level stands, and live corals collected along the Vietnamese coast of the South China Sea. The objectives of the project are to:

   1. reconstruct the fluctuations of sea levels at millennial to multi-decadal scales and the history of coral reef development since Early Holocene (post-glaciation) by using the TIMS U-series and radiocarbon dating techniques
   2. unlock the windows to sea surface temperature and sea surface salinity archives since the Early Holocene by using δ¹⁸O, Sr/Ca, Mn/Ca, U/Ca.
   3. define the timing of recent coral bleaching and high-death events. Water quality during death events is reflected by characteristic trace element concentrations, and Sr/Ca, Ma/Ca, U/Ca, Ba/Ca values, and rare earth elements patterns

This project is right on the cutting-edge of global climate change research and will be significant nationally and internationally to understand the natural environmental changes of our planet on long timescales, which can offer the context for understanding today's climate dynamics; anticipating how the planet might respond to future environmental perturbations; and for elucidating the impacts of natural versus anthropogenic influences.

Recent publications and abstracts:

Trinh, T. H., Le, P., Do, M.T., Pham, B.T., Nguyen, H.S, Nguyen, D.D, Nguyen, D.A., Le, D,M. (2000) Change and general trend of development of shoreline in the Cuadai estuary, Hoian, Quangnam province. In: Scientific Conference Bien Dong 2000, Nha trang (75-80).

Do, M.T., Nguyen, D.A., Pham, B.T. (2001) Research on affection of neotectonic activity to erosion-accretion process in the coastal estuaries from Danang to Sahuynh. Collection of marine research works. V. XI, 69 - 78.

Nguyen, D.A., Trinh, T.H., (2001) Some features of bottom surface sediment of the Xuandai Bay, Phuyen province. Collection of marine research works. V. XI, 79 - 88.

Do, M.T., Nguyen, D.A., (2002) Recent geological activities in the mouth area of Cunghau-Cochien river and solution for preventing the natural disasters. In: Scientific Conference Bien Dong 2002, Nhatrang p. 38-39.

Nguyen, D.A., Gasparon, M., (2005) Arsenic mobility at the Mole River Arsenic mine, Australia. In: The second International Congress of Chemistry and Environment (Ed. By S.L. Gargh) pp 778 - 786. Research Journal of Chemistry and Environment, Indore, India.

Nguyen, D.A., Gasparon, M., Baumgartl, T., (2006) Chemical and mechanical stability of waste rock at the Mole River Arsenic mine. In: International Student Conference, Brisbane pp. 73- 88.

Trinh, T. H, Nguyen, V. L., Pham, B. T., Tran, Q. K., Nguyen, D.A. (2005) Present status of landscape and reef fish resources at Cu Lao Cham archipelagos, Quangnam province. Marine Sciences and Technology, 2, 25-38.

Perach Nuriel

PhD Candidate

Degree: B.Sc & M.Sc, Ben-Gurion University of the Negev, Israel
Supervisor/s: Dr. Gideon Rosenbaum, Assoc. Prof. Sue Golding, Assoc. Prof. Jian-xin Zhao

Rm 130, Richards Building
Ph: 3346 9782
Email: Perach Nuriel

Project Title:
U-Th Dating and Geochemical Tracing of Paleo-Seismic and Paleo-climatic Events in the Dead Sea Fault Zone, Israel

We study calcite vein system located in a contractional strike-slip setting within the Dead Sea Fault Zone (DSFZ) in northern Israel. These calcite-filled fissures are closely associated with major N-S trending strike-slip fault structures and considered to represent the most recent and presently active phase of deformation (Weinberger et al., 2009). We use structural, U-Th dating, and geochemical analyses in order to study the timing and mechanism of fault-related vein formation. Calcite-filling veins may store important chronology of vein opening rates and major tectonic and climatic events. Once opened by extensional tectonism these fissures can act as rainwater and groundwater flow paths functionally similar to those developed by karst processes; and such tectonic environments can provide conditions favorable for accumulation of deposits preserving long, continuous paleoclimate and paleoseismic records.

Recent publications and abstracts:

Nuriel P., Katzir, Y., Abelson, M., Valley, J.W., Matthews, A., Spicuzza, M.J., Ayalon, A., 2009. Fault-related oceanic serpentinization in the Troodos ophiolite, Cyprus: Implications for a fossil oceanic core complex. Earth and Planetary Science Letters 282, 34-46.

Uysal, I.T., Feng, Y.-x., Zhao, J.-x., Isik, V., Nuriel, P., Golding, S.D., 2009. Hydrothermal CO2 degassing in seismically active zones during the late Quaternary. Chemical Geology 265, 442-454.

Nuriel P., Uysal I.T., Rosenbaum G, Weinberger R., Karabacak V., Golding S.D., 2008. Tracing paleo-seismic events in the Eastern Mediterranean (Turkey & Israel): U-series dating and stable isotope studies of co-seismic carbonate veins. Australian Earth Sciences Convention, Perth, June 2008.

Nuriel P., Weinberger R., Rosenbaum G., Golding S.D., Zhao J., Uysal I.T., Gross M., Karabacak V., 2008. Tracing of Paleoseismic Events in the Eastern Mediterranean: U-series Dating and Stable Isotope Studies of Syntectonic Carbonate Veins. American Geophysical Union, San-Francisco, December 2008.

Emma St. Pierre

PhD Candidate

Degree: BA Hons (Archaeology and Anthropology), University of Queensland
Supervisor/s: Jian-xin Zhao, Sue Golding (UQ), Mike Gagan (ANU) and Mike Morwood (UoW)

Rm 210B, Richards Building
Ph: 33467382
Email: Emma St. Pierre

Project Title:
Human-environment interactions in Australasia

This research takes a multi-disciplinary approach to understanding Holocene human-environment interactions in Australasia with a specific focus on the island of Flores, Indonesia. The geochemical study of speleothems from cave sites for palaeoclimate and palaeoenvironment reconstruction is used to investigate possible human impact on the environment and conversely potential impact of climate and environment change on the human population. U-series dating of speleothems at archaeological cave sites is used to establish and improve chronological sequences. These studies are used in addition to associated evidence from the archaeological record, to further understand human-environment interactions in this critical region of the world for human migration, evolution and adaptation.

Recent publications and abstracts:

St Pierre, E.J., Zhao, j-x., Dunbar, G.B., and Gagan, M.K. (2007). "Speleothem record of palaeoenvironmental change in southern Sulawesi, Indonesia during the last glacial to Holocene transition". Quaternary International, Vol. 167-168 Supplement.

Ayliffe, L.K., Gagan, M.K., Zhao, j-x., Drysdale, R.N., Hantoro, W.S., St Pierre, E.J., Smith, G.K., and Suwargadi, B.W. (2007). "Speleothems from Flores, Indonesia: tropical archives of climate". Quaternary International, Vol. 167-168 Supplement.

Griffiths, M.L., Drysdale, R.N., Gagan, M.K., Ayliffe, L.K., Zhao, j-x., St Pierre, E.J., Hantoro, W.S., Suwargadi, B.W.(2007). "Speleothems from Flores, Indonesia: tropical archives of climate ". Quaternary International, Vol. 167-168 Supplement.

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