Saturday, December 4, 2010

Goldschmidt Conference Abstracts 2009

Isotopic constraints on the genesis of
world-class REE-P-U-Th
mineralization, Nolans Bore, Central
Australia
R. MAAS1*, D. HUSTON2 AND K.HUSSEY3
1School of Earth Sciences, Univ Melbourne, Australia
(*correspondence: maasr@unimelb.edu.au)
2Geoscience Australia, Canberra, Australia
3Arafura Resources, Winellie, NT 0821, Australia
The Nolans Bore deposit in central Australia is one of the
world’s largest known REE resources (current estimates 30.3
Mt containing 850 kt REE-oxides, 3.9 Mt P2O5, 6100 kt
U3O8). Hosted in 1.9-1.8 Ga metasedimentary and metaigneous
rocks of the central Arunta region and postdating
1.60-1.57 Ga high-grade metamorphism, primary
mineralization occurs in NE-trending swarms of F-apatite
veins, associated with allanite, carbonate and calcsilicates. The
bulk of the REE is hosted in cheralite, bastnaesite and other
REE-rich mineral inclusions in apatite. Key geochemical
features include remarkably uniform, strongly fractionated
REE patterns (La/Lucn~281, Eu/Eu*0.89), elevated Ca, Sr, Th,
U, Y, F, CO2, but low HFSE. The mineralization is of hightemperature
hydrothermal origin and, although lacking
features such as alkalic minerals or fenitization, may be a
distal hydrothermal expression of concealed
carbonatitic/alkaline magmatism.
U-Pb dating of U-rich (260-700 ppm) F-apatite yields a
well-defined upper intercept age of 1244±10 Ma. All other
minerals analysed to date (allanite, pyroxene, epidote, garnet,
calcite) contain variable amounts of unsupported radiogenic
Pb (206Pb/204Pb 35-58), indicating loss of U-Th (or gain of Pb).
Initial 87Sr/86Sr ratios vary from 0.7047 to 0.7079, while
εNd1224 ranges from -12 to -4; there is no correlation between
Sr and Nd isotope ratios. All samples show some inter-mineral
Sr-Nd isotopic disequilibrium.
The 1244±10 Ma apatite U-Pb age, the only currently
available age constraint for mineralization, coincides with a
global spike in kimberlite, lamproite and carbonatite
emplacement (1300-1130 Ma), and several 1.3-0.7 Ga
carbonatite, lamprophyre and alkalic intrusive complexes are
known in Central Australia. Nolans Bore may be related to a
currently unexposed intrusive of this type. The low 87Sr/86Sr of
the ore fluid is consistent with such a source. Nd isotope data
are less diagnostic as initial εNd near -10 are characteristic of
the local Arunta Block crust at that time; however, low εNd
values would be also be consistent with a source ultimately
derived from lithospheric mantle.

Enigmatic archaea from the anoxic
terrestrial subsurface
J.L. MACALADY1*, D.S. JONES1, R. MCCAULEY1,
I. SCHAPERDOTH1, D. BLOOM1 AND S. MARIANI2
1Pennsylvania State Univ. University Park, PA 16802, USA
(*correspondence: jmacalad@geosc.psu.edu)
2Gruppo Speleologico CAI, Via Alfieri 9, 60044 Fabriano,
Italy
Cave divers exploring a remote underwater passage in the
sulfidic Frasassi cave system (Italy) discovered unusual, ropelike
microbial biofilms in anoxic water. Geochemical data
suggest that little redox energy is available for life, consistent
with low signal from domain-specific FISH probes. The
carbon isotope signatures of the biofilm (-33‰) and DIC
(-9‰) indicate in situ production by lithoautotrophs using
RuBisCO. 16S rDNA libraries constructed from the biofilm
are dominated by archaea in the enigmatic Marine Benthic
Group D (MBG-D/DHVE-1) along with diverse sulfate
reducing bacteria. Most of the remaining clones affiliate with
one of 11 major uncultivated or novel prokaryotic lineages.
Diverse dsrAB gene sequences were retrieved from the
biofilm, consistent with high sulfate concentrations and
undetectable or extremely low oxygen, nitrate, and iron
concentrations. Methane is detectable in the anoxic water
although no 16S rDNA sequences associated with known
methanogens or anaerobic methane oxidizers were retrieved.
mcrA gene sequences retrieved from the biofilm are not
related to cultivated methanogens or to known anaerobic
methane oxidizers. Our data suggest that novel archaea and bacteria,
including MBG-D archaea, are important in the dark, energylimited
cave biofilm. These microorganisms and their
potentially novel metabolic strategies are relevant for
understanding biogeochemistry and biosignatures of nonphotosynthetic,
energy-limited environments on the modern
and ancient Earth and elsewhere in the solar system.

Are arctic ecosystems exceptionally
vulnerable to global emissions of
mercury?
R. MACDONALD AND L. LOSETO
(robie.macdonald@dfo-mpo.gc.ca)
(lisa.loseto@dfo-mpo.gc.ca)
Almost one decade ago atmospheric mercury depletion
events (AMDEs) were reported to occur in the High Arctic
after polar sunrise (Schroeder et al., 1998), and these depletion
events were shown to result in mercury deposition to the
surface (Steffen et al., 2008). Although deposited mercury is
bioavailable (Lindberg et al., 2002) it remains unclear how
much – or even whether – the mercury actually enters
foodwebs (Hammerschmidt and Fitzgerald, 2008). These
findings raise the question of whether or not the Arctic is an
enhanced sink for global mercury emissions, and whether the
deposited mercury might explain high mercury concentrations
observed in some high trophic level Arctic biota. A recently
constructed mercury mass balance for the Arctic Ocean
(Outridge et al., 2008) found that atmospheric deposition is
important, accounting for perhaps half of the mercury inputs,
but that there are also other important sources (ocean currents,
rivers) and there is a large reservoir of mercury in the ocean
that could be worked on by various biogeochemical processes
(e.g., Poulain et al., 2007; Cossa et al., 2009). Perhaps more
intriguing is the lack of any correspondence between trends
for mercury in Arctic air (Steffen et al., 2008), and mercury
trends observed in high-trophic level aquatic animals
(Lockhart et al., 2005). This leaves open the questions of
whether or not the Arctic is a special sink, what proportion of
deposited mercury ends up in food webs (Loseto et al., 2008),
what factors produce variability in mercury concentration in
biota, and how might recent climate change, especially the
melting of ice, alter the Arctic’s mercury cycle (e.g.,
Macdonald et al., 2005)? These questions need answers before
we can properly assess the risks mercury presents to the
ecosystem.
In this presentation we focus particularly on the Arctic
Ocean and approach these questions by first examining what is
known about the quantities and pathways of mercury cycling
into and out of the Arctic. We then examine abiotic and biotic
processes that transform mercury to more toxic or bioavailable
forms to be taken up in foodwebs, and present available trend
data for mercury in different reservoirs. Finally, we propose
how climate change in the cryosphere might alter mercury
exposure by releasing archived mercury or transforming
cycling mercury. Throughout the discussion we point out
weaknesses in our understanding of the mercury cycle that
presently limit the development of a realistic model for the
mercury cycle in the Arctic.
The Brazeau Nisku Q-pool:
From sour gas reservoir to
acid gas storage
H.G. MACHEL
EAS Department, University of Alberta, Edmonton, Alberta
T6G 2E3, Canada (hans.machel@ualberta.ca)
The Brazeau Nisku Q-Pool in west-central Alberta,
Canada, was discovered in the 1980s as a sour gas reservoir in
the Upper Devonian Nisku Formation. The host rocks consist
almost exclusively of dolomite, with minor amounts of
anhydrite. The Brazeau Q-Pool is part of a reef trend that
contains oil, sweet and sour gas condensate at depths ranging
from about 2300 m in the northeast to more than 4200 m in the
southwest, with a thickness of about 80 to 100 m. A unique
feature of this play is that the hydrocarbons are contained in
numerous closely spaced pools that have been essentially
isolated hydrodynamically from one another since
hydrocarbon migration and entrapment about 50 - 60 million
years ago, as shown by initial reservoir pressures and gas
compositions. The hydrodynamic isolation renders these pools
suitable for acid gas (H2S + CO2) injection and/or carbon
dioxide (CO2) sequestration.
Today the Brazeau Nisku Q-Pool is one of more than forty
acid gas injection operations currently active in western
Canada. A thorough stratigraphic, diagenetic, mineralogical,
and hydrogeological evaluation of the Nisku Formation
suggests that the injected acid gas will remain in the structure
that contains the Q-Pool on a geological time scale. In the
unlikely case of migration out of the Q-Pool, the acid gas
plume would disperse and dissolve in deep formation waters
along the flow path. The only possibility for upward leakage
of acid gas rapid enough to be of human concern is through
wells that were improperly completed and/or are abandoned
and are not monitored


A new analytical field method for the
in situ determination of the oxygen
dynamics in groundwater
LARS MÄCHLER1,3*, MATTHIAS S. BRENNWALD1
AND ROLF KIPFER1,2
1Eawag, Swiss Federal Institute of Aquatic Science and
Technology, 8600 Duebendorf, Switzerland
(*correspondence:lars.maechler@eawag.ch)
2Institute of Isotope Geochemistry and Mineral Resources,
ETH Zurich, 8092 Zurich, Switzerland
3Institute of Biogeochemistry and Pollutant Dynamics, ETH
Zürich, Switzerland
The knowledge of oxygen dynamics in groundwater is
fundamental to understand biogeochemical processes.
However oxygen dynamics can only be studied if the
underlying physical gas exchange processes are understood in
a mechanistic and quantitative way. In recent years gas
exchange processes in porous media were thoroughly studied.
The resulting conceptual and quantitative models describe
gas/water partitioning in groundwater and yield mechanistic
insight in the formation of excess air, a commonly observed
super saturation of dissolved atmospheric gases (e.g. oxygen
or noble gases) in ground waters. The initial oxygen
concentrations typically exceed the atmospheric equilibrium
concentration considerably (>20%). Quantification of excess
air is therefore crucial to study the biogeochemical turnover of
oxygen in natural groundwater.
The solubility and diffusion coefficients of O2 in water are
similar to those of Ar. However, the Ar concentration in the
groundwater is unaffected by the geochemical processes of
oxygen turnover. Hence, the concentration of dissolved Ar is a
direct proxy that allows quantification of the initial oxygen
concentration at recharge. The difference of the initial oxygen
concentration with the concentration observed in a
groundwater sample corresponds to the oxygen consumed
since recharge of this water.
We developed a massspectrometric system for in situ
analysis of O2 and Ar concentrations in groundwater during
field work. The gas probe consists of a membrane inlet that is
submerged in the groundwater and separates the water from
the gas phase to be analysed. The probe is connected to a
quadrupole mass spectrometer (QMS200, SRS) via a tube of
several meters length to allow in situ analyses in groundwater
wells. A continuous vapor flow transports the gases to be
analysed (Ar, O2, N2, and possibly also CH4 and CO2) from
the probe to the mass spectrometer. The short response time of
the system (seconds to minutes) allows continuous analysis of
the dissolved gas concentrations in groundwaters. This enables
us to study the O2 dynamics, e.g. during bank infiltration of
groundwater in response to the hydraulic conditions of the
infiltrating river.
Iron removal enhancement of a
two step calcite passive treatment
system at the Iberian Pyrite Belt
FRANCISCO MACÍAS1*, MANUEL A. CARABALLO1,
JOSÉ MIGUEL NIETO1, CARLOS AYORA2
AND TOBIAS S. RÖTTING3
1Dpt. of Geology, Univ. of Huelva. Avda Fuerzas Armadas s/n
21071 Huelva, Spain (*francisco.macias@dgeo.uhu.es)
2Institute of Environmental Assessment and Water Research,
CSIC, Jordi Girona 18, E-08034 Barcelona, Spain
3HERO Group, Sir Joseph Swan Institute, 3rd Floor
Devonshire Building, Newcastle University, Newcastle
upon Tyne, NE1 7RU, United Kingdom
The previous calcite passive treatment systems developed
at Monte Romero (SW, Iberian Pyrite Belt) have shown a
significant effectiveness in iron and aluminum removal from
the highly polluted acid mine drainage (AMD) emerging from
the mine shaft. However, in previous experiments using two
reactive tanks in series filled with calcite Dispersed Alkaline
Substrate (Calcite-DAS), Al and Fe were not completely
removed. The system was modified to improve treatment
efficiency.
Anoxic acid discharge of Monte Romero mine flows
across several iron terraces where the acidophilic microbes
and atmospheric oxigen diffusion cause some iron oxidation
and subsequent removal. To enhance this natural attenuation, a
100m3 dam was built after several meters of the iron terraces,
and before the input of the passive treatment system (two 3m3
reactive tanks, Calcite-DAS, connected in series with two
decantation ponds).
AMD treated at Monte Romero has a pH of 3-3.5, a net
acidity over 1800 mg/L as CaCO3 equivalents and contains
440 mg/L Zn, 330 mg/L Fe (98% Fe+2), 100 mg/L Al, 3750
mg/L SO4 and 0.1-3 mg/L Cu, As, Pb, Co, Ni and Cd.
The natural attenuation (fomented by the dam) and the
passive treatment system showed excellents results. In the dam
almost 50% of ferrous iron were oxidized and 25% of ferric
iron precipitated. As well, 75% of As and 7% of net acidity
(140 mg/L as CaCO3) were removed from the emerging
AMD. Without the presence of the dam the oxidation and
removal of Fe in the iron terraces would be only 6% and 3%
respectively. The passive treatment system (Calcite-DAS)
eliminated a net acidity of more than 1300 mg/L as CaCO3
equivalents (72%) and removed 100% of Fe, Al, Cu, As, Cr
and Pb from the AMD.
This pretreatment by the dam requires only minimal
maintenance and no additional input of alkaline reagents


Skarn mineralization and related
hydrothermal alterations in Aliabad
Cu-porphyry deposit
(Taft-Yazd)
M.A. MACKIZADEH1*, F. DALIRAN2
AND B. TAGHIPOUR3
1Department of Geology, Esfahan University, Esfahan, Iran
(*ma_mackizadeh@yahoo.com)
2Geological Institute, University of Karlsruhe, Karlsruhe,
Germany (farahnaz.daliran@agk.uni-karlsruhe.de)
3Department of Earth Sciences, College of Sciences, Shiraz
University, Shiraz, Iran (goharrr@yahoo.com)
The area is a part of Cenozoic magmatic belt of Central
Iran which is contact in West of Yazd province & North-West
margin of Shirkuk batolite granite. Nayband terigenous
formation is the oldest rock unit as bed rock and has
undergone weak contact metamorphism by Shirkuh granite in
middle Jurasic. The young intrusive bodies which are mainly
leucocrate are granite to granodiorite with Cu-porphyry
mineralizations. They have widespread fractures & alterations.
Those intrusives have intruded Shirkuh granite, arcosic
sandstones & conglomerates of Sangestan formation (lower
Cretaceous). Skarns are formed in expense of carbonate huge
pebbles of Sangestan conglomerates. The following mineral
assemblage has been determined: garnet + epidote + quartz +
calcite + pyrite and turquoise.
Turquoise (Cu Al6 (PO4)4 (OH) 8 5H2O) is a phosphate
mineral with secondary origin that occurs veinlet shape in
volcanic rocks. This mineral is accompanied with other
mineral such as: alunite, jarosite, iron oxides and (Cu, OH)
carbonates in oxidation zone that formed in a late stage after
scarnization. Grassular formed in the kaoline, SiO2, CaO and
CaCl2 mixture in the 900°C and 2000 atmosphere pressure
(Dear et al, 1991). But volastonite and grassular formed in
500°C temperature in the mixture of silica, calcite and
aluminum oxide with ratio: 3 SiO2: Al2O3: 3 CaCO3 This
reaction supposed for formation of andradite (Dear et al.,
1991): 3CaCO3 + Fe2O3 + 3SiO2 = Ca3Fe2Si3O12 + 3CO2
Stable formation condition of andradite is in the high fO2
and temperature> 390°C. 1 and 2 area (Fig. ) that indicate
stable condition of garnet-pyrite and quartz. Hydrothrmal
alteration took place after contact metamorphism (skarn
formation) in intrusive bodies, skarns, conglomerates &
specially arcosic sandstones quartz-sericite-pyrite (or phyllic)
type alteration is characteristic in those rocks.
Subduction zone magmatism without
a slab-derived flux:
High-Nb basalts from Sabah
(Borneo)
COLIN G. MACPHERSON1, KAI KIM CHIANG2,
ROBERT HALL2, GEOFF M. NOWELL1,
PATERNO R. CASTILLO3
AND MATTHEW F. THIRLWALL4
1Department of Earth Sciences, Durham University, UK
(colin.macpherson@durham.ac.uk)
2Southeast Asia Research Group, Department of Earth
Sciences, Royal Holloway University of London, UK
3Geosciences Research Division, Scripps Institution of
Oceanography, USA
4Department of Earth Sciences, Royal Holloway University of
London, UK
Low concentrations of High Field Strength Elements
(HFSE) and their depletion relative to Large Ion Lithophile
Elements (LILE) and Rare Earth Elements (REE) are
characteristic of many subduction zone magmas. Some
subduction zones, however, have generated basaltic rocks in
which HFSE are abundant and only mildly depleted, or even
enriched, relative to the LILE. These “high-Nb basalt” have
been attributed either to (i) low degree melts derived from
beneath the slab, (ii) mantle wedge metasomatised by partial
melts of subducted basaltic crust, or (iii) melting of enriched
mantle without a significant slab input. Neither of the first two
models is consistent with compositions and spatial
distributions of Plio-Pleistocene high-Nb basalts from Sabah,
NE Borneo. First, the most primitive Sabah basalts are
isotopically similar to high-Nb basalts from SW Philippines
and several sites in the South China Sea, requiring similar
sources throughout SE Asia. This is highly unlikely to result
from mantle metasomatism by slab melts. Second, the Sabah
rocks are part of a Late-Miocene to Pleistocene low-volume
magmatic province extending SW into Borneo and NE into the
Philippines. Basement fabrics display similar orientations
suggesting that the lithosphere plays a key role in determining
the locus of magmatism. Either the sources of high-Nb basalts
reside in the lithospheric mantle, or they represent a regional
component of the convecting mantle from which melt is
transported along lithospheric structures. In either case, the
creation of the high-Nb basalt source is independent of
recent/active subduction. Sources of high-Nb basalt may melt
when subduction induces stress in arc lithosphere and/or
upwelling of sub-lithospheric mantle. The presence of high-
Nb basalt in several active arcs suggests that these sources can
escape modification by material derived from the slab through
the lifetime of a subduction zone.

Reactive transport modelling of a
long-term core infiltration
experiment with claystone
U. MÄDER1* AND TH. GIMMI1,2
1Institut für Geologie, University of Bern, Blatzerstrasse 3,
CH-3012 Bern, Switzerland
(*correspondence: urs.maeder@geo.unibe.ch)
2Laboratory for Waste Management, Paul Scherrer Insitut,
CH-5232 Villigen Switzerland (thomas.gimmi@psi.ch)
Argillacious rocks have low hydraulic conductivities (10-
14-10-13 m/s), large sorption and ion exchange capacities, are
homogeneous, and are thus consdiered as host rocks for deep
storage of radioactive waste in several countries. Constraining
multicomponent transport parameters for dissolved species are
of importance in this context.
A three-year advective-diffusive experiment under a
hydrostatic confining pressure with a preserved drill core from
Opalinus Clay (mid Jurassic, Switzerland) was used to (1)
displace the in situ pore water with an artificail pore water [1],
and (2) to monitor the breakthrough of tracres (2H, 18O, 36Cl,
Br) and major chemical components (this study). A multicomponent
reactive transport model (PHREEQC) was used
considering explecitly free porewater and pore water affected
by clay-bound diffuse double layers [2], species-specific
diffusion coefficients, ion-exchange, and slected carbonate /
silicate equilibria.
A much faster break-through is observed for Br- (an Cl-)
compared to 2H due to anion-exclusion effects and the
advective flow regime. While the break-through of individual
tracres can be modelled with a classical 1D
advection/diffusion approach constraining accessible
porosities and effective diffusion coefficients, an adequate
multi-component reactive transport model does require the
consideration of different types of accessible porosities, e.g.
including a diffuse-double layer model [2]. The elution
behaviour of cations is constrained by multi-component ion
exchange and ionic-strength effects that can drive some of the
eluted cation concentrations distinctly above those of the
infiltrating solution.
[1] Mäder et al. (2004) Proceedings of the 11th International
Symposium on Water-Rock Interaction, 445-449, Balkema. [2]
Appelo and Wersin (2007). [2] Appelo and Wersin (2007)
Env. Sci. Tech., 41, 5002-5007.
Adsorption of transgenic Cry1Ab
protein to the silica-water interface
MICHAEL MADLIGER, RENÉ P. SCHWARZENBACH
AND MICHAEL SANDER*
Institute of Biogeochemistry and Pollutant Dynamics, ETH
Zurich, Switzerland
(*correspondence: michael.sander@env.ethz.ch)
Bt crops are genetically modified to produce insecticidal
Cry proteins against pests. Bt crops release Cry to soils. Little
is known about adsorption of Cry to soil particles, albeit this
process governs Cry fate and bioactivity in soils. The aim of
this work was to systematically investigate and model the
adsorption of model protein Cry1Ab to silica (SiO2) as a
function of solution chemistry. To this end, we combined
solution-depletion experiments coupled to immunological
protein detection with in situ real time adsorption
measurements using quartz crystal microbalance (QCM-D).
Electrostatics governed the adsorption of Cry1Ab
(isoelectric point (IEP) = 6.4) to SiO2 (point of zero charge =
2-3) at I = 50 mM (NaCl). Favorable electrostatics at pH 5 and
6 resulted in fast and pronounced adsorption. At pH 5 and
c(Cry1Ab) = 10 μg mL-1, a protein monolayer formed on the
SiO2 surface. Conversely, at pH 7 and 8, no adsorption was
detected, due to electrostatic repulsion. At I = 10 mM,
electrostatics still governed Cry1Ab adsorption. Yet, proteinprotein
interactions and/or entropic effects facilitated
adsorption resulting in a protein bi-layer and a monolayer on
SiO2 at pH 6 and 7, respectively. Also, at pH 8, detectable
amounts of Cry adsorbed despite unfavorable electrostatics.
Adsorption at both I= 10 mM and 50 mM was highly
concentration dependent and reversible. Desorption rates
increased with increasing pH of the rinsing buffer. Control
experiments involving two additional proteins (bovine serum
albumin (IEP 4.6) and hen egg white lysozyme IEP = 10.5))
and positively and negatively charged polymers as adsorbents
confirmed the dominant role of electrostatics in Cry1Ab-SiO2
interactions.
Irreversible sorption of BSA to SiO2 pointed to structural
unfolding of BSA on the surface, resulting in a larger contact
area and hence an increase in the activation energy of
desorption. Conversely, reversible sorption of Cry1Ab
suggested that this protein remained in near native
conformation and that an adsorption-desorption cycle of did
not result in irreversible structural changes in Cry1Ab and
hence loss of its bioactivity. This was confirmed in diet
incorporation bioassays using the susceptible pest organism
Ostrinia nubilalis, where effect concentrations for 50%
growth inhibition of the test organisms were only slightly
higher for SiO2-adsorbed than freely dissolved Cry1Ab.

Episodes of gas hydrate dissociation
and enhanced methane flux recorded
by methane-derived authigenic
carbonates in the Gulf of Cadiz
V.H. MAGALHAES* AND L.M. PINHEIRO
Centre for Environmental and Marine Studies (CESAM) and
Geosciences Department, Univ. Aveiro, Campus de
Santiago, 3810-193 Aveiro, Portugal
(*correspondence: vhm@ua.pt)
Extensive occurrences of mud volcanoes, diapiric ridges,
pockmarks and methane seepages in the Gulf of Cadiz, often
fault controlled, are characterized by high methane contents in
the shallow sediments and by the presence of gas hydrates on
the most active structures, indicating that these are preferential
pathways for the escape of hydrocarbon-rich deep fluids
(mainly methane). Methane-derived authigenic carbonates
(MDAC) are found associated with mud volcanoes, diapiric
ridges or along faults, mainly along the upper and midcontinental
slope, where the Mediterranean Outflow (MO)
water is in direct contact with the seafloor.
Two distinct groups of MDAC are found in the Gulf of
Cadiz: one consisting of dolomite crusts, nodules and
chimneys, and the other of aragonite pavements, slabs, crusts
and buildups. The widespread abundance of MDAC is
interpreted as evidence of several episodes of extensive
methane seepage. Considering the minimum and maximum
temperature limits admitted to have occurred in the Gulf of
Cadiz, some MDAC samples indicate a formation from 18Oenriched
pore fluids that could have resulted from a
contribution of dissociated gas hydrates to the pore waters
from which the authigenic carbonates were formed. The
estimated U/Th ages of selected dolomite chimneys indicate
episodes of intense precipitation of the authigenic carbonates,
that correlate with periods of rapid paleoceanographic
changes, such as the onsets of glacial/interglacial terminations.
Calculations for the depth of the gas hydrate stability zone
for different paleoceanographic scenarios indicate that
increases in the seafloor temperature associated with glacial to
interglacial transitions and changes of the position of the MO
as a bottom current, could efficiently trigger episodes of gas
hydrates dissociation that would result in intense flux of
methane rich fluids to shallow sediments or even into the
seabottom.
Aerosol transformation and
scavenging in stratocumulus clouds
LEEHI MAGARTTZ, ALEXANDER KHAIN
AND MARK PINSKY
Department of the atmospheric Sciences, The Hebrew
University of Jerusalem, Israel (khain@vms.huji.ac.il)
A novel Lagrangian model of straocumulus cloud is used
for investigation of transformation of aerosol size distribution
and aerosol removal from the boundary layer covered by a
startocumulus clouds. The moldel consists of about 1500
lagrangian parcels that move within a turbulent –like flow
which statistical parameters are taken from observations. The
model takes into account processes of diffusion growth,
collisions, droplet scavenging and mixing between parcels.
The stratocumulus clouds observed during research flights
RF01 and Rf07 of the field experiment DYCOMS-II are
simulated.
The model described diffusion growth of wet aerosols to
drops and back to wet aerosols during droplet evaporation.
The amount of aereosols in each bin of aerosl/drop size
distribution is calculated at each time step. It is shown that
aerosols within drops grow by collisions, so that drizzle
contains largest aerosols. The rate of aerosol scavenging by
drizzle is evaluated. The salinity of drops of different size is
calculated. The evaluated rate of aereosol scavenging can be
used for estimation of necessry rate of aerosol production in
the atmosphere (assuming the balance of the aerosol mass in
the atmosphere).

Geochemical zonation in Mirkoh
alimirza area, Arasbaran zone,
NW Iran
A. MAGHSOUDI1, M. YAZDI2, M. MEHRPARTO3
AND M. VOSOGHI ABIDENI4
1Faculty of Earth Science, Shahid Behshti University, Tehran,
Iran (ab_maghsoudi@yahoo.com)
2Faculty of Earth Science, Shahid Behshti University, Iran
3Geological Survey of Iran (GSI), Tehran, Iran
4Faculty of Earth Science, Shahid Behshti University, Iran
The Mirkoh Ali Mirza area is located in the Arasbaran
zone. Arasbaran Zone in NW of iran is a metallogenic
province of Cenozoic age. Mineralization in this zone is
associated mainly plutonic-volcanic-related porphyry copper,
skarn copper-gold and epithermal gold deposits.
The major exposed rocks in the area are related to
Neogene volcanic and subvolcanic rocks. The local
mineralization is structurally controlled, and are localized
preferentially in faults and fault intersections. The alteration is
dominated by quartz, propylitic, argillic, sericite.
Recent geochemical studies within the north of Mirkoh Ali
Mirza area shows a distinct lateral metal zonation of gold and
base metals which can be used as a guide to exploration of
copper porphyry at depth in the adjacent magmatic systems.
Chemical variation include Cu as disseminated sulphides and
stockwork systems in the center of suvolcanic-volcanic dom.
The Au-Ag mineralization shows lateral zonation to outside of
the Cu mineralization. The outside chemical zonation
continues to Sb, Pb, Zn, Ba and Mn.
Data processing of geochemical data shows low but
anomalous values for Mo, W, Be and Bi which are associated
with the Cu-Au-Ag-Sb mineralization. These elements are
sensitive indicators of physicochemical conditions during the
ore deposition and therefore can be used as a tool for outlining
the center of hydrothermal activity in the sub volcanic body
and hydrothermal fluid evolution respect to time and space.
Evaluation study of CCS for the
mitigation measure of atmospheric
CO2 and ocean acidification by the
global carbon cycle model
MICHIMASA MAGI
Research Institute of Innovative Technology for the Earth,
Kizugawadai 9-2, Kizugawa, Kyoto, Japan
(magi@rite.or.jp)
Background
IPCC AR4 reported that the emission of the anthropogenic
Carbon Dioxide (CO2) increase the CO2 concentration in
atmosphere after the Industrial Revolution, and increasing of
CO2 concentration caused the global warming. Moreover, it is
shown that CO2 dissolution into the ocean causes the
acidification in the surface layer. The buffering effect of the
ocean can suppress the change of the CO2 concentration in the
atmosphere. However, the rise of the CO2 concentration in the
ocean surface means the pH of seawater decreases. This
phenomenon continues until the difference of CO2 partial
pressure between the atmosphere and the ocean disappears if
the emission of CO2 is stopped. But, the acidification of the
ocean progresses as long as it keeps CO2 emission. It is feared
that the ocean acidification has crises influence on various
organisms and entire ocean ecosystem.
Methods and Results
Carbon Capture and Storage (CCS) is one of the
mitigation measure technologies of CO2 emission. Famous
carbon storage technology of the CCS using ocean region is
sub-seabed geological storage (SGS) and dilution type ocean
sequestration (DOS). The evaluation and comparison study for
atmospheric CO2 decreasing measure and ocean acidification
mitigation measure was carried out using 3-dimensional
numerical model with ocean circulation model and a global
carbon cycle model based on a lower trophic ecosystem
model. The results of the simulation study under the several
scenarios showed “SGS without leakage is the best as the
effect of measures”. And it is suggested that “There is a
possibility of suppressing the ocean surface acidification to
more effective by combining DOS with SGS”. This study is
supported by the CCS project of RITE under the fund from
METI.

On lithium isotope systematics and
abundances in lunar mare basalts
T. MAGNA1*, C.R. NEAL2, P.B. TOMASCAK3,
B. BOURDON4, F. OBERLI4 AND J.M.D. DAY5
1Univ. Münster, Germany
(*correspondence, tomas.magna@uni-muenster.de)
2Univ. Notre Dame, USA (neal.1@nd.edu)
3SUNY Oswego, USA (tomascak@oswego.edu)
4ETH Zürich, Switzerland (bourdon@erdw.ethz.ch,
oberli@erdw.ethz.ch)
5Univ. Maryland, USA (jamesday@geol.umd.edu)
Recent studies of lunar mare basalts and volcanic glasses
[1,2] have revealed resolvable δ7Li differences between the
melt products of low-Ti olivine-orthopyroxene-rich cumulates
and high-Ti clinopyroxene-dominated lithologies formed
after extensive crystallization of the lunar magma ocean
(LMO), where the high-Ti basalts carry a higher δ7Li
signature. To more rigorously assess δ7Li variations in the
Moon, we have analyzed a variety of lunar low- and high-Ti
mare basalts from the Apollo 11, 12, 14, 15 and 17 sites for
their Li abundances and isotope compositions. The new data
indicate broad δ7Li homogeneity for the suite as a whole, with
a few subtypes clearly deviating from the main field, and only
subtle differences between low- and high-Ti basalts. High-K
A-type basalts from the A11 site show a significant imprint of
Li-rich material, likely consistent with addition of a KREEP
component [3]. This is further corroborated by our new
estimate of KREEP δ7Li and Li abundances derived from
KREEP basalt 15386 and impact melt 14310. C-type basalts
from the A17 site have consistently higher δ7Li than all other
mare basalts, which may relate to metasomatic overprint by
alkali-rich fluids [4], rather than the effect of clinopyroxene
accumulation [1]. The δ7Li variability of A17 high-Ti mare
basalts provides further evidence for their origin from heterogeneous
mantle sources [5]. Subtle δ7Li fluctuations within
individual A12 flows (olivine, pigeonite and ilmenite basalts)
can be explained by fractional crystallization of olivine (± pigeonite).
Our new results for olivine-normative A15 basalts
(ONBs) further underscore their differences with A15 quartznormative
basalts (QNBs) [1], possibly indicating gradual
evolution of their common source via accumulation of olivine
in ONBs and plagioclase accumulation in QNBs [6].
[1] Magna et al. (2006) Earth Planet. Sci. Lett. 243, 336; [2]
Day et al. (2008) Lunar Planet. Sci. Conf. XXXIX, #1072; [3]
Jerde et al. (1994) Geochim. Cosmochim. Acta 58, 515; [4]
Neal et al. (1990) Lunar Planet. Sci. Conf. XXI, 855; [5]
Rhodes et al. (1976) Lunar Planet. Sci. Conf. 7th; 1467; [6]
Schnare et al. (2008) Geochim. Cosmochim. Acta 72, 2556.
Why weathering rates differ between
the laboratory and the field
KATE MAHER1, CARL I. STEEFEL2
AND ART F. WHITE3
1School of Earth Sciences, Stanford University
(*correspondence: kmaher@stanford.edu)
2Earth Sciences Division, Berkeley National Laboratory
(CISteefel@lbl.gov)
3U.S. Geological Survey, Menlo Park, CA
(afwhite@usgs.gov)
In order to understand how experimentally-determined
rate constants and kinetic rate laws can be extrapolated to
capture the overall rates and chemical evolution of natural
systems, a reactive transport model was used to fit the aqueous
chemistry, mineral saturation state and solid elemental and
mineral abundances
from a well-studied
chronosequence at
Santa Cruz, CA.
Rate constants were
initially calculated
for the primary
dissolving minerals
(albite and Kfeldspar)
and the
dominant
precipitating
mineral (kaolinite)
using a simple
linear TST approach. The intrinsic rate constant for the linear
TST model was found to be 2 orders of magnitude smaller
than the experimentally determined laboratory rate constant,
even though the effect of kaolinite precipitation on the fluid
saturation state was accounted for. The ability of the linear
reference model to match the available data was compared to
simulations that used experimentally-derived rate constants
and rate laws with a non-linear dependence on the approach to
equilibrium. When a non-linear dependence on the approach
to equilibrium was considered using alternative rate law
formulations, we found that the calculated rate constants were
within error of experimental rate constants for the same fit to
the data. These results suggest that the discrepancy between
experimentally and field-calculated rates is not purely a result
of close-to-equilibrium dissolution in natural systems, but
depends on the particular form of the rate law as reaction rates
approach equilibrium and on the identity and solubility of
precipitating minerals.
intermediate
late gas potential
low late gas potential high late gas potential
0.45 0.5 0.55 0.6
late gas ratio (1) (LGR1) 0.6
0.8
1
1.2
1.4
late gas ratio (2) (LGR2)
Petroleum Type Organofacies
PNA High Wax
PNA Low Wax
Paraffinic
Gas + Condensate



High temperature methane as an
unconventional gas source
N. MAHLSTEDT* AND B. HORSFIELD
GFZ German Research Centre for Geosciences,
Telegrafenberg, 14473 Potsdam, Germany
(*correspondence:nick@gfz-potsdam.de)
Late gas potential evaluation
In this study we consider in detail which source rocks
possess a late gas potential in general. Late dry gas generation
can be expected for organic matter with R0 > 2.0% and for
geologic temperatures in excess of 200°C [1, 2]. This may, in
addition to the cracking of unexpelled oil, contribute
significantly to the accumulation of thermogenic gas in gas
shales and coal seams.
Figure 1: Late gas potentials of analysed source rocks, based
upon C1-5 and C6+ MSSV-pyrolysis yields at 560°C and 700°C
(see equation 1 and 2 for the late gas ratios definition).
Equations: Late gas ratios (MSSV-pyrolysis)
(1)
(2)
Discussion of Results
High late gas potentials (LGR1 > 0.55) are mainly seen for
terrestrial influenced type III to type II/III shales and coals.
The late gas yield cannot be attributed to secondary cracking
of C6+ compounds alone (LGR2 > 1) but is related to the
decomposition of a
neoformed
recombination
residue generated at lower
maturation levels [1, 2].
[1] Erdmann & Horsfield (2006), Geochim. Cosmochim. Acta
70, 3943-3956. [2] Dieckmann et al. (2006), Mar. Pet. Geol.
23, 183-199.
Climate impacts on annual-average
airborne particle source
contributions in California
ABDULLAH MAHMUD1, ZHAN ZHAO2,
MARK HIXSON1, JIANLIN HU2, SHU-HUA CHEN2
AND MICHAEL J. KLEEMAN1*
1Department of Civil and Environmental Engineering,
University of California at Davis, One Shields Avenue,
Davis, CA 95616.
(*correspondence: mjkleeman@ucdavis.edu)
2Department of Land, Air, and Water Resources, University of
California at Davis, One Shields Avenue, Davis, CA
95616
California has one of the worst particulate air pollution
problems in the United States with some estimates predicting
more than 5000 premature deaths each year attributed to air
pollution. Climate change will modify weather patterns in
California with unknown consequences for airborne
particulate matter (PM). Previous down-scaling exercises
carried out for the entire United States have typically not
resolved the details associated with California’s mountainvalley
topography and mixture of urban-rural emissions
characteristics. Those detailed studies specifically carried out
for California have identified strong effects on PM acting in
opposite directions making the net prediction for climate
effects on PM somewhat uncertain. More research is needed to
reduce this uncertainty so that we can truly understand climate
impacts on PM and public health.
The objective of this research is to predict climate change
effects on annual average concentrations of particulate matter
(PM) in California with sufficient resolution to capture the
details of California’s air basins. Particular emphasis will be
placed on trends in source contributions to PM in the presence
of climate change. Business-as-usual scenarios generated by
the Parallel Climate Model (PCM) will be downscaled to 4km
meteorology using the Weather Research Forecast (WRF)
model. The CIT/UCD source-oriented photochemical air
quality model will be employed to predict PM source
contributions throughout the entire state of California. The
modeled annual average total and speciated PM concentrations
for the future (2047-2049) and the present-day (2004-2006)
periods will be compared to determine climate change effects.
The results from this study will improve our understanding of
global climate change effects on PM source contributions in
California.

Combined FISH, µ-XRF and SEM
analysis to examine microbe-metal
interactions on root surfaces
R.M. MAIER*, J. CHOROVER, S.L. IVERSON
AND S.M. HAYES
Department of Soil, Water and Environmental Science,
University of Arizona, Tucsion, AZ 85721, USA
(*correspondence: rmaier@ag.arizona.edu)
Metalliferous mine tailings in arid regions pose a
significant health risk to proximal populations because they
are prone to wind-borne dispersion and water erosion. The
problems are extensive and persistent as impacted sites lack
normal soil stabilization processes. Phytostabilization is the
revegetation of mine tailings to ameliorate these issues with
the goal of root zone metal accumulation to avoid metals from
entering the food chain through above-ground biomass. The
role of plant roots and microbes in promoting mineral
dissolution-precipitation reactions and associated metal
sequestration is an active area of research, but little is known
about reaction trajectories and changes in particle-scale metal
speciation of plant-tailings systems, owing largely to their
geochemical heterogeneity and microbial complexity. Since
the form or speciation of a metal controls its bioavailability
and toxicity, research that probes coupling between metal
speciation and microbial dynamics in response to
phytostabilization is needed. The goal of this research is to
develop methodology to combine the use of fluorescent in situ
hybridization (FISH), microfocused-x-ray fluorescence (u-
XRF), and scanning electron microscopy (SEM) to assess the
spatial heterogeneity and relationship between bacterial
colonization (FISH) and metal distribution (u-XRF) on root
surfaces of plants grown in metalliferous tailings. Initial data
will be presented that show FISH, u-XRF, and SEM can be
technically combined to examine the same root sample. These
initial results visually co-localize bacteria with metal
precipitates on root surfaces.
The Bluebush Zinc Prospect, NW
Queensland: Multiple base metal
mineralising events and a record of
fluctuating redox conditions in late
Palaeoproterozoic seas
RODNEY C. MAIER AND PETER J. MCGOLDRICK*
Centre of Excellence in Ore Deposits, University of Tasmania,
Hobart, Tas 7001, Australia
(*correspondence: p.mcgoldrick@utas.edu.au)
The Bluebush Zinc Prospect is a huge accumulation of
weakly Zn mineralized bedded pyrite in sedimentary rocks of
late Palaeproterozoic age. It is obscured by Mesozoic
sedimentary cover some 55 – 350 m thick, but geophysical
surveys indicate that pyrite-rich stratigraphy occupies an area
at least 25 x 10 km. Anomalous Zn grades (0.5 – 1wt%) are
present over intervals up to a few tens of metre thick in both
reduced and oxidised rocks.
The sequence is conformable, laterally continuous, and
composed of organic-rich silt, shale, and chemical sediments,
significantly modified by diagenetic and hydrothermal
alteration. Zinc mineralization occurs over 600 m of
stratigraphy comprising a lower (reduced) facies that is highly
pyritic and and contains distinctive ‘fluidal’ pyrite and
carbonate textures. This unit is overlain by thick-bedded
(barren) mass flow deposits, which are in turn overlain by a
distinctive green-pink laminated and nodular (oxidised) facies
containing magnetite (minor hematite) and chlorite. The
oxidised facies is Zn mineralized and passes gradationally
upwards into barren siltstones and pyritic, carbonaceous
shales.
Sulfide textures and pyrite trace element chemistry
support a multi-stage (diagenetic) origin for the Zn
mineralisation [1].
The redox changes manifested in the sedimentary facies
variations can be accounted for in terms of relative sea level
changes over time [2]. However, we will present new S
isotope data from pyrite that suggest high productivity
(perhaps associated with a brine pool) had role in producing
the lower pyritc facies, whereas, the upper pyritic unit formed
in a more ‘normal’ Proterozoic deep marine setting.


Environmental constrains on
microbial methane oxidation activity
and community structure in Gulf of
Cadiz mud volcanoes
L. MAIGNIEN, N. BOON AND THE RV JAMES COOK JC10
SHIPBOARD SCIENTIFIC PARTY
LabMET, Ghent University, Belgium
(*correspondence: lois.maignien@ugent.be)
In the Gulf of Cadiz, mud volcanism is supporting the
development of cold seep ecosystems based on the Anoxic
Oxidation of Methane (AOM). Due to the variety of eruptive
processes and geochemical settings, these mud volcanoes
(mv’s) constitute an ideal natural laboratory to study the AOM
microbial community ecology. During the RV James Cook
JC10 cruise, we targeted three mv’s, with the aim to measure
methane turnover, its potential controls and associated
microbial diversity. Sulphate reduction and methane oxidation
activities were measured using radio-labelled substrates
immediately upon sediment recovery, whereas diversity
survey was carried by mean 16s rDNA libraries.
Typical Methane and sulphate gradients associated with
AOM were present in the sediment except at MERCATOR mv
where dissolution of gypsum (CaSO4) maintained high
sulphate concentration along the entire core. The lowest
activities were measured at MERCATOR mv, where salt
concentration up to 10 times sweater concentration may
inhibit the AOM reaction. At DARWIN mv, discrete AOM
near-surface hot-spots sampled with the Remote Operated
Vehicle ISIS resulted in highest activities and revealed the
heterogeneous nature of this mv. Archaeal and bacterial 16S
rRNA gene clone libraries showed that AOM communities
differed considerably between these three mv’ s. At DARWIN
and CARLOS RIBEIRO mv’s, AOM communities were
relatively diverse and dominated by ANME-2, ANME-3 and
associated sulfate-reducing bacterial phylotypes, whereas
AOM diversity at MERCATOR was much lower and
dominated by the ANME-1b phylotype. Overall, these results
demonstrate the influence of several environmental parameters
such as sediment geochemistry, seep relocalization following
carbonate crust development and methane flux on the
microbial activity and community structure at these cold seep
sites.
Study of petrology and magmatic
evolutions in west part of Shir Kuh
batholite
SH. MAKVANDI1, N. RASHID NEJAD2
AND F. MASOUDI3
1Tarbiat Modares University, National geosciences database of
Iran
2Tarbiat Modares University
3Tarbiat Moalem University
Western part of Shirkuh Granitoid Batholite is a
peraluminous multiphase plutonic complex based on
geochemistry and petrography studies. In this complex
considered as S-type granites due to the presence of mica and
garnet, silica range (65-75%), high A/CNK ratio, calc-alkaline
characters and syncollisional volcanic arc setting. At the same
time, younger phases are belived as I-type bodies because of
their petrography, major elements, oxide trends and spiky
spider diagrams.
Pertite texture is resulted in high-K replacement processes.
This texture is the most common texture in Shirkuh Complex
which is along to graphic overgrowth textures indicates that
this complex is a subsolvus granite, crystallized in the high
vapor pressure conditions. Furthermore, geochemistry analysis
and petrography represent Hydrothermal Fluids invasion and
metasomatic origin at least in some parts of this Batholite

Sulfide mineral paragenesis at the
Hugo Dummett porphyry Cu-Au
deposit, Oyu Tolgoi, South Mongolia
S. MYAGMARSUREN* AND H. FUJIMAKI
Tohoku University, Sendai, 980-8578, Japan
(*correspondence: sanjaa_m@ganko.tohoku.ac.jp,
h-fujimaki@mail.tains.tohoku.ac.jp)
Mineralogical studies of ore minerals have been conducted
for the Hugo Dummett porphyry copper-gold deposit. The
Hugo Dummett porphyry Cu–Au deposit is hosted within Late
Devonian quartz monzodiorite intrusions, augite basalt and
dacitic ash-flow tuff situated in the South Gobi region,
Mongolia.
Copper-gold mineralizations at this deposit are centered
on a high-grade copper (> 2.5%) and gold (0.5–2 g/t) zone of
intense quartz veining. Intense quartz veining (up to 90% by
volume) forms a lens up to 100 m wide, hosted by augite
basalt and spatially by quartz monzodiorite.
The Hugo Dummett porphyry copper-gold deposit is
characterized by three mineralized stages based on textural
relationships of ore minerals: (1) early stage (2) middle stage
and (3) late stage. The main copper-gold mineralization occurs
in the early and middle stages, which is related to the quartz
monzodiorite and dacitic ash-flow tuff. Pyrite, chalcopyrite
and bornite occur in all stages. The early stage of pyrite,
chalcopyrite, bornite, molybdenite and sphalerite were
replaced by middle stage of minerals. The middle stage
minerals are sphalerite, tennantite, tetrahedrite, chalcocite,
covellite, eugenite, galena, electrum, and gold, those are
dominantly occur in the quartz monzodiorite. Eugenite is
determined in trace amount for the first time in the Hugo
Dummett deposit. Additional pyrite, bornite and chalcopyrite
were also deposited during this stage. In the late stage, pyrite,
chalcopyrite and bornite are dominantly occurs as veins,
veinlets and fracture filling in the quartz.
Chemistry of bacterial interfaces:
Functional group composition and
implications for metal and mineral
surface complexation
S.C.B. MYNENI AND B. MISHRA
Department of Geosciences, Princeton University, Princeton,
NJ 08544, USA
Knowledge on the composition of surface functional
groups and their reactions is critical in determining the role of
bacteria in bacterial mediated biogeochemical reactions.
However, bacterial surface chemistry is less well understood,
and most of our current understanding comes from the
potentiometric titrations of isolated cell wall membranes.
Using STXM, and X-ray and infrared spectroscopy we studied
the C-, N-, P-, and S-functional group composition of Grampositive
and Gram-negative cells.
Our studies indicate that all identified functional groups
and their relative concentrations are similar to both Grampositive
and Gram-negative bacterial surfaces, without any
detectable differences. The dominant functional groups are as
follows- C: unsaturated C=C (aliphatic and aromatic), C=O of
amide and carboxyls, and C-N of amines; N: amine and
amides; P: phosphate esters; S: methionine. Several other
groups, such as aromatic N and cysteine, are identified at low
concentration, but they play an important role in the metal and
mineral surface complexation reactions.
Bacterial cell surface functional groups exhibit different
affinities with metals based on the functional group type and
the Lewis acidity of metal. For example, Hg reactions with
bacteria showed that Hg preferentially reacts with cysteine and
exhibits different coordination geometries at nanomolar Hg
concentration. However, Hg binds to carboxyls at micromolar
concentration. A summary of bacterial surface functional
groups, and their reactions with selected metals will be
discussed.

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