The Lake Laach region as monitoring test site

The Lake Laach region
as
monitoring test site
Ingo Möller
October 17-19, 2011
Maria Laach, Germany
2nd CGS Europe Knowledge Sharing Workshop
Natural Analogues
Acknowledgements
Many thanks to
Kai Spickenbom
Christian Seeger
Dave Jones
BGR: Eckhard Faber, Martin Krüger, Dietmar Laszinski, Franz May, Jürgen Poggenburg, Nicole Rann, Stefan Schlömer, Christian Wöhrl
BGS: Tom Barlow, Patricia Coombs, Kay Green, Bob Lister, Jonathan Pearce, Richard Shaw, Michael Strutt, Julian Trick, Ian Webster, Julie West
LUWG (Mainz): Olaf Prawitt
NIAH: Volker Böder, Harro Lütjens, Arne Sauer
Inst. Geosciences (Univ. Mainz): Frank Sirocko & staff
URS: Giorgio Caramanna, Salvatore Lombardi
others: Michael Uhlenbruch, Ansgar Hehenkamp, Benedictine Abbey of Maria Laach, SGD Nord (Koblenz)
Rationale
Deployment of geological CO2 storage implies the capability to
detect possible leakage from reservoirs and eventual effects on
the environment, especially the biosphere including human
health
Monitoring as essential system component within the planning,
selection, installation and operation of geological CO2 storage
sites
Monitoring performance must ensure different methodological
components:
Detection
Verification & characterization of spots suspicious to leakage
Long-term-Monitoring in case of confirmed releases
Only a selected combination of different methods and
technologies can fulfill these necessities
Regional setting
Lake Laach is one of the
volcanic centres of the East
Eifel volcanic field
Located in the uplifting
Paleozoic Rhenish Massif
which represents the
Devonian basement
Its eruption at about 12900
yr bp is the only known large
explosive eruption in Central
Europe during late
Quaternary
Neighbouring quarternary
volcanic centres are at
Rieden and Wehr
Like at Lake Laach, their
eruptions (Rieden: ~430380 ka, Wehr: ~300-150
ka) have formed calderas
Other dominant features:
cinder cones and related
lava flows, ignimbrites &
volcanic ash and tuff
Precondition: Presence of CO2
Dissolved carbon species and free CO2 reach the surface at many
places in the East Eifel volcanic field (and other regions of the
Rhenish Massif)
Isotope analyses (noble gases and carbon) show a geogenic origin
of the CO2
It is linked to the magma source of the volcanic fields which is
located in the upper earth mantle, in an area of reduced seismic
velocities, known as “Eifel Plume”
There, magnesium rich magmas, which
are formed by partial melting of
peridotite, take up CO2 and release it
during ascent in the lower earth crust
(due to pressure release and cooling of the
magma)
In the fractured upper earth crust, CO2 migrates along the
margins of basement blocks and faults, where it comes in
contact with groundwaters. Water-rock interactions consume
some of the CO2 (transformation into dissolved bicarbonates and solid
carbonates)
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Carbonic and other
mineral springs
Environmental leakage
indicators
CO2-influenced life
communities
Deep CO2 „reservoirs“ &
industrial analogues
Sketch of the Analogue Inventory
Mofettes
10m
Surface survey
Large-area sidescan sonar survey
Underwater ROV survey
Sketch of the Analogue Inventory
Mofettes
Long-term gas flux monitoring experiment Lake Laach 2011
April 5, 2011
water depth: 7.8 m
September 19, 2011
Sketch of the Analogue Inventory
Mofettes
r = 0.3
r = -0.63
r = 0.65
Long-term gas flux monitoring experiment Lake Laach 2011
Gas flow rate (running hourly mean) vs.
water temperature, air pressure (not corr.) & wind speed
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
„Vent 1“
δ13C values
CO2 (Vol%)
Lake Laach,
western side
Large-scale
perspective
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Langer (1988)
Small-scale
perspective
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Carbonic and other mineral springs
e.g. cold water geysirs
Sketch of the Analogue Inventory
„Pferdebrunnen“
CO2 gas : 94.7 – 97.8 Vol-%
δ13CCO2 : -4.7 to -3.8 ‰
HCO3: 1010 mg/l
pH
: 5.78
Conductivity: 1265 µS/cm
Oxygen saturation: 0.4 - 2.6 mg/l
Redox potential: 35 - 40 mV
„Römerbrunnen“
CO2 gas : 89 – 96 Vol-%
δ13CCO2 : -4.6 to -5.1 ‰
HCO3: 1820 mg/l
pH
: 6.39
Conductivity: 2480 µS/cm
Oxygen saturation: 5.6 mg/l
Redox potential: 35 mV
e.g. captured springs
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Carbonic and other mineral springs
Environmental
leakage
indicators
Wehr
Small-scale
perspective
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Carbonic and other mineral springs
Environmental leakage indicators
Fe(III)-oxides
Stands of Carex sp.
in dry, terrestrial habitats
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Carbonic and other mineral springs
Environmental leakage indicators
CO2-influenced life communities
Large-scale
perspective
Sketch of the Analogue Inventory
Mofettes
Dry mofettes
Carbonic and other mineral springs
Environmental leakage indicators
CO2-influenced life communities
Deep CO2 „reservoirs“ & industrial analogues
Results of the CCS-related R&D work
„onshore“
„offshore“
Example: Stable carbon isotopes from CO2 gas
Clear isotopic distinction between deep, inorganic CO2 and shallow,
biological CO2 (though atmospheric influence, mixture &
fractionation)
Normally, CO2 generated from burning fossil fuels have isotopic
signature well differentiated from “environmental” C isotope
values. However, some CO2 species might have an isotopic
signature which is similar to that of shallow biogenic CO2
Results, continued
A good number of established and reliable methods and tools
exist for the near surface monitoring at CO2 storage sites
regarding
gas monitoring
bio monitoring (micro and makro cosmos)
eco monitoring (populations and systems)
They represent a huge toolbox
for confidence building;
confidence in technology
with regard to markets and
the public
(confidence Æ acceptance)
Results, continued
Development & evaluation of suites of techniques
enabling
small-scale surveys to detect eventual leakage
pathways on a regional level (and to contribute to
baselines)
a rapid surveying of relatively large areas and the
derivation of essential results in short time (and
even real time)
detailed large-scale verification and characterization
procedures for selected study sites
the use of local knowledge to target possible sites of
gas migration and/or release
continuous monitoring and discrete measurements
Definition of a flexible multi-level approach for the
(near surface) monitoring at CO2 storage sites of
different types:
Detection
Verification
Characterization
Long-term monitoring
Lessons-learnt
Reliable techniques exist that can distinguish
deep, geogenic CO2 from shallow, biogenic CO2
Leakage, if it occurs,
can be quantified by detailed flux measurements
Permanent gas monitoring stations are able
to observe short-term variations and
to differentiate anomalies from the background
The detection of CO2 gas is able to resolve even low levels
Once detected, the quantification accuracy is still orders of
magnitude higher;
less than 0.001 – 0.003 t per year, i.e.
less than 5 – 10 g per day
Lessons-learnt, continued
What we need is:
Baseline monitoring (besides monitoring during operation) that
reveals natural (e.g. seasonal) variations for relevant objects
explains the determining factors of these variations
seems to be specific for individual storage sites
starts well before the first CO2 injection just to have
sufficient time for the interpretation of recorded data
Systematical link between (the results of)
near surface and subsurface monitoring efforts