Planetary Geology

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Planetary Geology
Coordinator: Olga Prieto
Members of the research line: José Javier Álvaro Blasco , Ricardo Amils Pibernat, Tania Barragan Gonzalez, David
Fernández Remolar, Maite Fernández Sampedro , Miriam García Villadangos , Damhait Gleeson , Felipe Gómez
Gómez , Laura Jiménez Bonales , Fernando Izquierdo Ruiz, Emmanuel Aléxis Lalla, María Paz Martín Redondo,
Jesús Martínez Frías , Paloma Martínez Sarmiento, Jesús Medina García, Irene Melero Asensio , Antonio Molina
Jurado, Victoria Muñoz Iglesias , Delphine Nna Mvondo, Jens Olof Ormö, Fernando Rull Pérez, Mónica Sánchez
Román, Antonio Sansano Caramazana, José Aurelio Sanz Arranz, Fernando Tornos Arroyo, Jesús Ignacio Velasco
Acebes, Gloria Venegas del Valle
Resumen: Planetary Geology is the study of solid surface planetary objects in the Universe, including Earth. Specifically, this
scientific discipline investigates the composition, structure and processes and agents by which planets, satellites, comets,
asteroids and meteorites evolve since its formation. These issues are crucial in determining the habitability of planetary
environments, and basically outline the main objectives of this research area at CAB: 1) participation in planetary exploration
missions, 2) determination of the influence of the geology on extreme paleo-, and current terrestrial environments analogous to
those developed on other planets, 3) the characterization of planetary material regarding habitability, and 4) understanding the
geological processes that affects the evolution of the planets and natural satellites. The close relationship with other fields of
astrobiology, which arises naturally during the approach to these problems, is well reflected in the activities that were carried
out during 2012.
Participation In Planetary Missions
The experience of the researchers working in Planetary
Geology and Astrobiology is required for the
development of instruments and planning planetary
mission to different solar system bodies. 2012 was very
fruitful for CAB regarding participation in planetary
missions, to be noted two milestones with significant
participation of researchers of the area of Planetary
Geology: In May 2012, the European Space Agency
(ESA) elected the mission JUICE (Jupiter Icy Moon
Explorer) as the first large-budget mission to be
executed within the Cosmic Vision program. This
mission, in which members of CAB have worked for
more than five years, will arrive to the Jupiter system in
2030. The main themes of this mission are the study of
the emergence of habitable worlds around gas giant
planets, with particular interest to the satellite
Ganymede, and the examination of the Jupiter system
as an archetype of such planets in the Universe.
Another important event occurred in August 2012
when the Curiosity rover of MSL (Mars Science
Laboratory) mission managed by NASA (National
Aeronautics and Space Administration) reached the
surface of Mars and began its explorations. Since then,
the science team of the REMS instrument (Rover
Environmental Monitoring Station) led by CAB and
with participation of members of this research line
began the operations and data interpretation. REMS
reports daily on atmospheric pressure, humidity and
ultraviolet radiation on the Martian surface, data of
great importance for the understanding of the current
environment and how it affects the rocks on Mars'
surface.
The development of a Raman spectrometer for the
ExoMars mission, led by members of this research line,
continues in technological and scientific success.
Significant progress is made in the spectrometer
development with components in temperature,
radiation, and thermal and mechanical design. There
has been extensive work in the excitation laser to
optimize its performance and stability as well as on the
optical head, whose responsibility within the
international consortium fell on the German team so
far, but now also includes Spanish involvement.
Numerous tests have also been executed at INTA’s to
establish the radiometric model of the spectrometer,
estimate the calibration functions at different
temperatures, and verify scientific requirements. The
results of these trials have been excellent. Also, there
have been substantial advances in software, algorithms
and the spectral processing mode. Among the activities
to support the science of the instrument are those
related to the simulator equipment, which includes the
development of a Martian environmental chamber for
studies of polycrystalline samples with flattened
distribution following the procedure of the ExoMars’
rover, and on relevant geological samples. This
chamber is considered of great value to ESA for future
testing in coordination with the rover's analytical
laboratory. The most important tests are those where
the Raman is combined with other instruments such as
MOMA and Micromega, and in particular using
unknown samples where Raman has shown great
ability to detect both minerals and organic materials,
and also in the analysis of perchlorates in
polycrystalline samples.
In addition, members of the research line have also
participated in scientific meetings related to the
development of exploration strategies and techniques
to detect life on samples to be retrieved by a future
sample return mission to Mars. Likewise, members of
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Figura 1. Simulation of planetary processes and environments in the unique facilities at CAB. A) The
Experimental Projectile Impact Chamber (EPIC) in the Laboratory for Experimental Impact Cratering,
and B) High Pressure Equipment for the analysis of planetary geochemistry.
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the research line are also participating with their
geological expertize in the development of the Mercury
Imaging X-ray Spectrometer (MIXS) mineralogical
mapper instrument developed for the Bepi Colombo
mission to Mercury to be launched in 2015. This
geological reference work focuses on the effects of
impact cratering, the dominant surface process of
Mercury and most other solid objects in the solar
system, and is carried out through experiments in the
unique Laboratory for Experimental Impact Cratering
at CAB (Fig. 1A) as well as through remote sensing and
field studies of natural impact craters.
Characterization Of The Geology Of Current Extreme
Environments And Paleo-Environments
During the year 2012 various extreme environments of
great interest to astrobiology visited. Geological field
work provided samples for mineralogical, geochemical
and biogeochemical analysis. These analyses were
performed both in the laboratory facilities of CAB as
well as other collaborating institutes, including the
University of Western Ontario (Canada), the Natural
History Museum in London (United Kingdom) and the
University of Salamanca (Spain). Most of the explored
environments are in part analogs to some environments
observed at planetary objects in our solar system, like
Mars or Europa. Concerning the exploration of
inaccessible places, their study has been possible
thanks to the support of local researchers and
institutions, such as the GNS-Science (Institute of
Geological and Nuclear Sciences, New Zealand), the
University of Chile or the Spanish Polar Committee and
the Army, which manage the Antarctic bases.
One example of active extreme environments explored
in 2012 is the hydrothermal systems on the seafloor in
New Zealand, and those located in cold climate areas
such as Deception Island (Antarctica). Investigations
have also been carried out on the genesis of singular
magmas
of
magnetite-apatite
and
associated
hydrothermal systems in the Andes (Chile).
Environments of fossil hydrothermal systems are being
studied for some time in El Jaroso, Cabo de Gata and
the Iberian Pyrite Belt (Spain). In this regard, the
further development of the EU-funded project Iberian
Pyrite Belt Subsurface Life (IPBSL) has included the
drilling of the basement at the Rio Tinto to study the
community of microorganisms that induce the extreme
conditions of the river. In 2012, the drilling of the
longest borehole was completed, which reached the
depth of 613 meters. During this campaign, the drilling
and sampling of the terraces of the Rio Tinto river
system has also proceeded for evaluating the degree of
preservation of biological information in extreme
conditions dominating over 7 million of years. In
addition to that, sampling inside some caves has been
performed to determine the processes of crystallization
of minerals (carbonates and sulfates) that appear there,
such as some from Almeria (Spain) and northern Italy.
In some cases, the interest of a geological site is that its
rocks record periods of Earth history in which decisive
events occurred for the environment or the life of the
planet. This occurs in several studied Neo-ProterozoicCambrian outcrops including primitive microbial
communities (e.g. Montagne Noire in France, Atlas in
Morocco, Ossa Morena in Portugal and Spain, or in the
Baltic of Russia) (Fig. 2).
During 2012 some interesting results from the analysis
of samples from previous campaigns have been
obtained, such as details regarding the sedimentation
and microbial associations with hydrothermal
mineralization within Proterozoic rocks (Burkina Faso)
and the salt basins from the Neoproterozoic-Cambrian
(Mauritania), evidences by TOF-SIMS analysis of
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Figure 2. A) Image of a columnar stromatolite in a carbonatic rock that marks the Marinoense glaciation (basal
Ediacaran) in Kayes (Mali) taken with a petrographic microscope with parallel light. It shows alternating layers of
microbial mats and barite cement (BaSO4), developed on a low temperature hydrothermal emanation, where sulfur
is provided by the sea and barium hydrothermal fluid). B) Brecciated rock from a slope flanking a microbial reef
complex of the Lower Cambrian unit of Ossa-Morena (Estremoz quarries, Portugal)
organic aggregates comparable to bacterial cell
structures in rocks of the Achaean age obtained during
the 2011 Barbeton campaign (South Africa), detection of
biological bearing molecules such as DNA, proteins or
protein complexes that have great potential for
preservation in hypersaline deposits of Atacama (Chile)
that are analogs of chlorides deposits observed in
Sirenum Terra on Mars, or details of the microbial
communities associated with the permafrost of
Deception Island (Antarctica).
In addition, contributions to realize some 1/50 000
maps edited by the Ministry of Energy and Mining,
Morocco have been realized, such as The Atrous, Irara,
Merzouga, M'fis and Taouz (Tafilalt, eastern AntiAtlas).
Characterization Of Planetary Material Related To
Habitability
The essential elements for life are contained in the
materials of the geosphere, atmosphere and
hydrosphere of the planetary objects. In the area of
Planetary Geology planetary minerals, fluids and their
interactions
are
investigated
from
different
perspectives. One method involves the experimental
analysis on both natural samples (e.g. meteorites) and
synthetic samples. Another procedure for obtaining
information about the composition of a planetary object
is the analysis of sensor data from space missions such
as spectrometers of different wavelengths or mass
spectrometers.
An advantage that CAB’s researchers have is the
availability of facilities for experimental simulations of
planetary environments, e.g. the high pressure
equipment that allows studies of solid and liquid
materials in the conditions of deep planetary
environments such as the oceans of the icy satellites
and niches within the crust of rocky planets. During
2012, there have been some equipment modifications to
optimize both, the control of the temperature and for
obtaining the spectroscopic signal within the chambers
(Fig. 1B), and various experiments for characterization
of materials at high pressure were carried out, e.g. the
crystallization of hydrated minerals associations at the
prevailing pressures in the crust and ocean from
Europa satellite. This was used to assess the evolution
of the cryomagmas involved in mobilizing liquid water
within this icy satellite. High pressure experiments are
part of the collaboration with the Spanish network of
scientists working at high pressure in the context of a
Consolider-Ingenio project (MALTA).
Also, the development of spectral databases of minerals
for applications of the Raman instrument of ExoMars
mission has continued during this period. Analyzes
have been made of the material changes due to Martian
conditions
and
the
structural
transformation
phenomena (especially the hydration-dehydration
process) that can happen when the samples obtained
under the Martian surface enter the rover for analysis.
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Characterization Of Geological Processes
The evolution of planetary objects is determined by the
geological processes that affect their internal and
external dynamics. Some of these processes are of
particular interest because they have effects on the
environments in which life can develop or thrive, i.e.
the formation of habitats through access to energy
source (hydrothermalism) and space (fracturing). The
cratering phenomenon is extended to all the planets of
the solar system and has great relevance to
Astrobiology because it greatly disturbs the surface
properties of the impacted object. The cratering process
is sensitive to these surface properties and an analysis
of the craters formed by this exogenous process can be
used to reconstruct paleo-environments that could have
supported, or even still support, life, for instance past
aquatic environments or ground water/ice reservoirs.
In the Laboratory for Experimental Impact Cratering at
CAB, meteorite impact processes are studied through
experiments with projectiles in Experimental Projectile
Impact Chamber (EPIC), with numerical simulations,
field studies at natural craters, and through the analysis
of planetary analogous data. In 2012, the installation of
the hardware facilities has finished, and tests have been
performed to verify the scaling relations between the
obtained experimental impact craters and large natural
craters. The impact process is analyzed with a new high
resolution camera. Experiments at oblique impact
angles over stratified targets have been conducted,
which is essential for the understanding of the layered
upper crust of Mars, impacts in oceanic environments,
as well as calculations on deflection techniques of lifethreatening near earth objects. Furthermore, some
reference structures for impacts into layered marine
targets that were already under study such as the
Lockne/Malingen doublet impact structure (Sweden),
and the Wetumpka crater (USA) have been analyzed to
even greater detail, and a new structure was discovered
in the high Swedish arctic (the Vakkejokk breccia) that
show promising features for the understanding of
ejecta formation in a wet-target environment.