22-EPN3-076: Aeolian Ripples Development under Martian Atmospheric Conditions

22-EPN3-076: Aeolian Ripples Development under Martian Atmospheric Conditions

Visit by Simone Silvestro and Giuseppe Mongelluzzo of INAF (Italy), to TA2.4 Planetary Environment Facilities (PEF), AU (Denmark)
Dates of visit: 16-20 October 2023

Report summary: In our experiments in the Planetary Environment Facility in Aarhus we obtained, two superimposed ripple patterns on monodisperse (90-150) glass beads in CO2 air. The presence of two distinct sets of aeolian sand ripples in unimodal sand suggests two formational mechanisms, impact for the cm-scale ripples and hydrodynamic for the decimetre scale set. We also run the experiment for natural 125µm-sand for terrestrial and Martian pressures (and below). Two patterns might be visible, but not very clearly, suggesting that the shape of the grains is playing a role in the formation of the hydrodynamic pattern. We also found a potential inverse relationship between impact ripple wavelength and pressure that we are currently investigating.

Fig. 1: Ripple pattern obtained in the wind tunnel. a) two ripple sets formed in glass beads at 1031 mb. b) ripples in natural 125µm-sand at 250 mb. Two patterns might be distinguished but they are not as evident as in the glass beads. c) ripples at 4 mb in natural sand. Only one pattern can be distinguished. Credit: Silvestro et al.

20-EPN-064: Impact induced polypeptide synthesis on low-temperature astrochemical ices containing amino acids

20-EPN-064: Impact induced polypeptide synthesis on low-temperature astrochemical ices containing amino acids

Visit by Ragav Ramanchandran and Jaya Krishna Mekaof the Physical Research Laboratory, Ahmedabad, (India), to TA2.7 Light Gas Gun Laboratory, University of Kent (UK)
Dates of visit: 25 June – 10 July 2023

Report summary: Impacts are the most common events across the solar system, shaping the evolution of planetary bodies,including icy satellites, such as Jupiter’s moon Europa, which are prime targets for future space missions finding signatures of life. Impacting bodies are known to deliver important organics, such as amino acids, to the planetary surface and sub-surface. Apart from this, high pressure and temperature created during impacts can provide pathways for chemical reactions leading to the formation of more complex molecules from simple precursors. Thus impacts have significant consequences for the potential habitability and synthesis of organic compounds.

We performed a series of experiments at the light gas gun facility of the University of Kent, simulating the impact on targets containing amino acids embedded in water ice. A stainless steel bolide of size 1.5 mm was used as a projectile and fired at a velocity of ~ 5 km s-1. After impact, the ejecta ice materials were collected in a specially designed chamber, and materials were also collected from crates and theirsurroundings that were formed after impact. The collected materials will be analyzed using different techniques for the identification of synthesized products after impact. Previous studies suggested that building blocks of life, such as amino acids, can be synthesized by impact-induced processes. However, it is unknown how the formation of macromolecular architectures from the combination of simple building blocks would have happened. Our objective with these experiments will be to explore the formation of such macromolecules through impact events and explore potential pathways toward life.  


22-EPN3-016: Noble Gas Tracing the Paleo-Fluids Involved in the Origin of the Crystal Caves

22-EPN3-016: Noble Gas Tracing the Paleo-Fluids Involved in the Origin of the Crystal Caves

Visit by Petronela Ševčíková, Slovak Hydrometeorological Institute (Italy), to TA2.18 Isotoptech Noble Gas Laboratory, Debrecen (Hungary).
Dates of visit: 27 November – 07 December 2023

Report summary: We employed Noble gasses as a tracer of past and recent fluids, that may relate to the crystal caves origin. Samples represented the early and the late crystallisation of calcites (difference in 18O) of 6 caves located in different distances from large Neogene volcanic province in central Slovakia, samples of Quartz vein from the Kremica Stratovolcano, and samples of recent thermal waters in vicinity of studied caves. The question to address in this study was, whether, and to what extent, the early crystallisation fluids were mixed with fluids from a large volcanic province 12+ km to the South of the studied caves, or whether they were local fluids equilibrated with crystalline basement.

During the analytical phase we ran into unforeseen difficulties with high background, and we spent large portion of time until the background was low enough to permit the measurements. During 10 days we were able to measure five samples, where He and Ne concentrations are reliable, but the Ar-Kr- Xe fraction is affected by the incomplete purification, which indicates the presence of hydrocarbons in the fluids. The results show very high concentration of Helium with clear crustal signal of 3He/4He. Among the measured samples (all calcites) two represent the early crystallization, two represent late crystallisation and one sample was not distinguished (lacked the late phase). The lowest He concentrations were recorded for one ‘early’ sample and one ‘undistinguished’ sample and the phases representing the late crystallisation returned higher He concentrations. The difference is up to two orders of magnitude.

(Figure reproduced from full scientific report with kind permission by Petronela Ševčíková.)

20-EPN-046: Impact-induced volatile release from calcium sulphates anhydrite and gypsum

20-EPN-046: iVOL – Impact-induced volatile release from calcium sulphates anhydrite and gypsum re-investigated in an open system by two-stage light-gas gun impact experiments

Virtual visit by Christopher Hamann and Robert Luther of Museum für Naturkunde Berlin (Germany), to TA2.7 Light Gas Gun Laboratory, University of Kent (UK)
Dates of visit: 01 September 2021 – 01 May 2022

Clarifying the response of volatile-bearing materials such as sulphates and carbonates to hypervelocity impacts is important, as it relates to the potential modification of planetary atmospheres by release of volatiles. However, most previous studies aimed at delineating the shock behaviour of sulphates and carbonates were done using confined or ‘closed’ setups (e.g., shock-recovery experiments) that hampered formation and escape of volatile species resulting from shock compression and subsequent release. Here, we focus on calcium sulphates, which are abundant on Earth and Mars and are likely targets of hypervelocity impacts. 

By using the two-stage light-gas gun at the University of Kent Light Gas Gun Laboratory, we investigated the response of gypsum (CaSO4⋅2H2O) and anhydrite (CaSO4) to hypervelocity impacts in a fully unconfined or ‘open’ system that allowed impact-induced formation and escape of volatiles such as H2O and SO2/SO3 as well as recovery of shocked materials. By petrographic investigation of shocked, solid ejecta and materials lining the impact craters, we find that dehydration of gypsum to anhydrite proceeds via bassanite (CaSO4⋅0.5H2O) and results in distinct changes of microtextures (e.g., dehydration cracks) and Raman spectra (e.g., weakening of water Raman bands). In addition, further devolatilization of sulphur-bearing species from anhydrite or solid dehydration products as well as melting is suggested from a distinct Ca-enrichment in µXRF element distribution maps and certain microtextures (e.g., spherical objects resembling melt spherules) observed under the SEM, respectively. These characteristics may be used to identify shocked calcium sulphates among terrestrial or extraterrestrial (e.g., future Martian) samples.


22-EPN3-037: Alteration and Element Mass Transfer from Source to Sink in Planetary Crusts

22-EPN3-037: Alteration and Element Mass Transfer from Source to Sink in Planetary Crusts

Virtual visit by Astrid Holzheid (Kiel University, Germany) to TA2 Facility 23 – Open University Flow Through Simulation Chambers (UK).
Dates of visit: 19-23 February 2024

Report Summary: Sound knowledge of the processes and conditions that drive hydrothermal systems is one of the prerequisites to understand not only the geological, geochemical, and geophysical evolution of our planet and other terrestrial planets, especially Mars, but also to shed light on the origin and early evolution of life since hydrothermal systems can be hospitable to certain life forms.

The use of the unique experimental set-ups of the reaction chambers at Open University allows determination of the mass transport of dissolved metals with either continuous sampling of the fluid or recirculation the fluid with built-in Ti gaze as precipitation traps. We used this set up to better understand environmental conditions during active hydrothermal alteration.

The source rocks of the experiments were fresh basalts from the Indian ocean ridge that served as analogue material to the Martian surface. The fluid was Indian ocean seawater sampled 100m above seafloor.

We observed precipitation of minerals like Ca-sulphates, NaCl, FeOOH and Fe-Mg-Na-containing clay minerals, but also native Ta and Fe-Ni-Cr alloy. While the ions of the mineral phases originated from leaching of the basalt, the metals might have come from the stainless-steel tube that served as container of the Ti gaze.

Based on the newly formed minerals, the pH – redox state – conditions can be deduced. This information is a prerequisite together with the cations enriched in the post-run fluid phase to allow geochemical reaction-path modelling which will be the next step after the post-run fluids are analysed at Kiel University.


22-EPN3-092: Deciphering Traces of Life from the Dawn of Earth’s Biosphere

22-EPN3-092: Deciphering Traces of Life from the Dawn of Earth’s Biosphere

Visit by Nisha Ramkissooon (The Open University, UK) to TA2.2 VU (Exo)Planetary Interior Simulation Laboratory (PISL).
Dates of visit: 12-16 February 2024

Report Summary: In the search for evidence of ancient terrestrial life there are some obstacles. Purported biosignatures have been identified in a range of ancient mineral deposits, including silica. However, some of these signatures can also be generated under abiotic conditions, which brings into question their biological origin. In addition, the oldest fragments of the Earth’s crust are at least 3.8 Gyr, and would have experienced significant metamorphic alteration since their formation. Therefore, any preserved biosignatures could have also undergone extensive modification during metamorphism potentially making some of them unidentifiable. This project aimed to examine the effect of metamorphism on the modification of biosignatures preserved in silica deposits. 

Silica sinters were synthetically created in the laboratory via evaporation in the presence and absence of microbes. These samples were then exposed to simultaneous high temperature and high pressure conditions using the end-loaded piston-cylinder at the (Exo) Planetary Interior Simulation Laboratory (PISL), VU University, Amsterdam. Samples were individually subjected to pressures and temperatures of 650 °C and 12 kbar, respectively, for 20 hours. Raman spectroscopy and GC-MS will be used to assess changes in mineralogy and to quantify changes to organic molecules. Initial results obtained after returning to my home institution show that the high pressure and high temperature conditions experienced in these experiments led to changes in the crystalline structure of the samples. This resulted in samples transforming from silica glass to quartz. 


22-EPN3-124: Unfolding Geochemical Evolution of the Subcontinental Lithospheric Mantle

22-EPN3-124: Unfolding Geochemical Evolution of the Subcontinental Lithospheric Mantle Recorded by Diamond-Forming Carbon and Water Rich (C-O-H) Mantle Fluids Throughout Time

Virtual visit by Yael Kempe and Ofir Tirosh (The Hebrew University of Jerusalem, Israel) to TA2.1 VU Geology and Geochemistry radiogenic and non-traditional stable Isotope Facility (GGIF).
Dates of visit: 9 November 2023 – 25 January 2024.

Report Summary: Fibrous diamonds from the Voorspoed, Venetia and Koffiefontein mines record deep mantle events involving C-O-H fluid types, alongside gem diamonds containing mineral inclusions that were related to modification episodes of the Kaapvaal lithospheric region. Although a connection has been made, the longstanding debate between diamond formation in the mantle and the relationship between gem diamonds and fibrous diamonds is yet to be resolved.

While we have extensive radiometric dating of mineral inclusions trapped in gem diamonds, alongside knowledge about the major and trace elements of C-O-H fluid microinclusions in diamonds, their radiogenic isotopic data is insufficient (e.g. Sr, Nd, and Pb isotopes). High-precision Sr-Nd-Pb isotope TIMS analyses of C-O-H mantle fluids in diamonds from these three prime locations in the Kaapvaal craton were preformed using a novel laser ablation diamond-in-water technique, combined with ultra-low blank column chromatography and 1013 Ohm resistors.

The team successfully processed and analysed 12 samples from Voorspoed, 5 from Venetia and 5 from Koffiefontein mines, as well as standards and blanks. The collected data show intriguing Sr-Nd-Pb relationships that vary between diamonds carrying different C-O-H fluids. The team has further data processing and calculations to complete, as well as correlate the isotopic ratios with trace element compositions to fully understand the results and their geological significance. The outcome of this Europlanet project is expected to provide new insights into the complex tectonic history of this lithospheric province, the fluids themselves and the connection between different diamond types and their formation mechanism.


22-EPN3-063: The Origin of Early Archean Barite

22-EPN3-063: The Origin of Early Archean Barite – Insights from the Geochemical and Isotopic Composition of Associated Chert Deposits

Visit by Desiree Roerdink (University of Bergen, Norway) to TA2.1 VU Geology and Geochemistry radiogenic and non-traditional stable Isotope Facility (GGIF).
Dates of visit: 6-10 November 2023

Report Summary: The formation of bedded barite (BaSO4) deposits in the low-sulfate environments of the early Earth has been a long-standing paradox despite decades of field and geochemical studies. In this project, the team investigated the Si isotope geochemistry of chert (SiO2) dykes and beds found in association with barite to evaluate roles of hydrothermal fluids and seawater during barite formation. A total of 14 chert samples from three localities in the ~3.3 Ga Mapepe and Mendon Formations of the Barberton Greenstone Belt, South Africa were microdrilled and dissolved using sodium hydroxide digestion. Pure silicon fractions were obtained using cation exchange chromatography columns, and analysed for 29Si/28Si and 30Si/28Si isotope ratios by multi-collector inductively-coupled plasma mass spectrometry (MC-ICP-MS) in wet plasma mode using standard-sample bracketing for mass bias correction. Measured silicon isotope ratios (δ30Si) range from 0.27 to 1.29‰. Chert dykes (n = 6) and bedded cherts (n = 3) have similar silicon isotopic compositions, with an average δ30Si value of 0.88‰ for the dykes and 0.80‰ for the bedded cherts. Black chert from the Mendon formation is isotopically distinct (δ30Si = 0.45‰) from the Mapepe Formation cherts. These results tentatively suggest that the chert dykes and bedded cherts associated with barite formed from isotopically-heavy seawater (δ30Si > 0‰), and that the role of high-temperature hydrothermal fluids (δ30Si < 0‰) was limited. 


22-EPN3-074: Emergence of Ice Ripples by Sublimation at Various Wind Velocities and Air Pressure

22-EPN3-074: Emergence of Ice Ripples by Sublimation at Various Wind Velocities and Air Pressure

Visit by María Belén Maté and Ramón Javier Peláez (IEM-CSIC, Spain) to TA2.12 Atomki-Queen’s University Ice Laboratory for Astrochemistry (Hungary).
Dates of visit: 07-11 November 2023

Report Summary: The possibility that prebiotic precursors of life formed in the space and were then transported to the early Earth by comets, asteroids and meteorites is a fascinating hypothesis. We focus in this project on hydroxylamine, NH2OH, a key N-bearing species that has been proposed as an important precursor in the formation of amino acids like glycine or alanine. Very recently, hydroxylamine has been detected in the gas phase in dense clouds in the interstellar medium. It has been predicted to form efficiently on dust grains according to laboratory experiments and chemical models. Then, the presence of this species in ISM ices and on the surface of Solar System bodies is probable, and in those surfaces can react to form more complex prebiotic species like amino acids.

Although the chemical pathways leading to the formation of NH2OH in astrophysical ices have been thoroughly studied, the next step in the chemical evolution that would begin with NH2OH as a precursor in ice has, to our knowledge, not been addressed experimentally.

In this TA project the team studied the chemistry induced by Cosmic Rays on ices containing hydroxylamine. They studied pure NH2OH ices and mixtures with H2O, CO and D2O, at 20 K, irradiated with 15 keV H+ ions. In particular, we were interested in finding complex organic molecules in the processed ices, and learning how different ice composition affects the chemistry and the destruction efficiency of NH2OH by Cosmic Rays.


22-EPN3-065: Ion Bombardment of Glycine and Glycine Embedded Within Water Ice in Solar System and Interstellar Conditions

22-EPN3-065: Ion Bombardment of Glycine and Glycine Embedded Within Water Ice in Solar System and Interstellar Conditions

Visit by Alfred Hopkinson (Aarhus University, Denmark) to TA2.12 Atomki-Queen’s University Ice Laboratory for Astrochemistry (Hungary).
Dates of visit: 04-08 December 2023

Report Summary: During this TNA visit, the simplest amino acid glycine (NH2CH2COOH), and its deuterated analogs, partially deuterated d3-glycine (ND2CH2COOD) and fully deuterated d5-glycine (ND2CD2COOD), were irradiated using 10 KeV protons. The subsequent products of this processing were then measured using infrared spectroscopy and a quadrupole mass spectrometer. The aim of this was to investigate the products of glycine destruction and investigate if this energetic processing could result in the formation of glycine peptides. The outcome of the TNA visit was the collection of infrared spectra of the irradiation of these molecules and then following this, temperature-programmed desorption measurements. These preliminary results show the formation of CO2, CO, and D2O.

Full scientific report published by kind permission of Alfred Hopkinson.


22-EPN3-053: Proton Processing of Phenanthrene Ice Mixtures for Application to Titan’s Lower Atmosphere

22-EPN3-053: Proton Processing of Phenanthrene Ice Mixtures for Application to Titan’s Lower Atmosphere

Visit by Alessandra Candian and Annemieke Petrignani (University of Amsterdam, Netherlands) to TA2.11 Atomki Ice Chamber for Astrophysics / Astrochemistry (ICA) (Hungary).
Dates of visit: 4-8 March 2024

Report Summary: During this TNA visit, the three-ring PAH phenanthrene (C14H10), acetonitrile (CH3CN) and their 1:1 mixture were irradiated using 10 KeV protons. The subsequent products of this processing were then measured using infrared spectroscopy (5000-700 cm-1) and a quadrupole mass spectrometer.

The aim of these experiments was to investigate 1) if energetic processing can modify the structure of solid hydrocarbons and 2) if proton irradiation could trigger the formation of new species. During the visit to Atomki, the team collected infrared spectra of at different proton fluences and then following this, infrared spectra during temperature-programmed desorption (TPD). They also obtained the residues after TPD for ex-situ analysis. The preliminary results show a) the puckering of phenanthrene solid, b) the formation of ethanimine (C2H5N) in acetonitrile solid, c) a complex behaviour of the 1:1 mixture, with puckering and formation of new hydrocarbon species.

Full scientific report published by kind permission of Alessandra Candian and Annemieke Petrignani.


22-EPN3-091: Evolution Under Radiation of Organics Pertaining to Europa

22-EPN3-091: Evolution Under Radiation of Organics Pertaining to Europa

Visit by Alexis Bouquet (Aix-Marseilles University, France) to TA2.11 Atomki Ice Chamber for Astrophysics / Astrochemistry (ICA) (Hungary).
Dates of visit: 19-24 February 2024

Report Summary: Several of the icy moons of Jupiter possess a liquid water ocean under a thick icy crust. In the especially promising case of Europa, a young surface (>100 Myr), and likely recent cryovolcanicactivity (within the last 8 years) imply the presence of ocean material on the surface. Therefore, observations performed by space missions could determine the ocean’s composition, and derive indications on its potential habitability (presence of chemical gradients providing metabolic energy, quantity and composition of available organic matter…). Characterising Europa’s ocean and its possible habitability requires to understand processes that alter organic and inorganic molecules in this environment. These processes include the processing by energetic ions coming from Jupiter’s magnetosphere and hitting the surface.

In this project, Alexis Bouquet visited the Atomki facility to study the effect of sulfur ion bombardment on methanol, a species that could be indicative of key characteristics of the ocean, pure and within an ice matrix. The alteration of the sample was followed using infrared spectroscopy, and the resulting complex organic residues were retrieved for ultra-high resolution mass spectrometry.

Full scientific report published by kind permission of Alexis Bouquet.


20-EPN2-090 – A Search for Thiols Formation Pathways Under Space-Relevant Conditions

20-EPN2-090 – A Search for Thiols Formation Pathways Under Space-Relevant Conditions

Visit by Zuzana Kaňuchová (Astronomical Institute of the Slovak Academy of Sciences, Slovakia) and Tom Field (Queen’s University Belfast, UK) TA2.11 Atomki Ice Chamber for Astrophysics / Astrochemistry (ICA) (Hungary).
Dates of visit: 27 November – 8 December 2023

Report Summary: Despite being only the tenth most abundant element in space, sulfur is a component of several biomolecules, making it a key subject for astrochemistry studies. Sulfur containing molecules were observed in the solid phase on the surfaces of icy moons and in the icy mantles of interstellar grains. Despite the seemingly ubiquitous detection of sulfur-bearing species in space, the sulfur budget is still puzzling the scientific community. To address this, Zuzana Kaňuchová and Tom Field conducted an exploratory series of irradiation experiments to determine if species with thiol (-SH) groups may be formed in hydrocarbon-rich ices at temperatures relevant to interstellar matter, the surfaces of Solar System icy satellites, and Kuiper Belt objects.

They implanted 200 keV S+ ions in methane (CH4), ethane (C2H6), ethene (C2H4), and ethyne (C2H2) ices at 20 K and 60 K. Formation (and destruction) of species was monitored via FTIR spectroscopy and quadrupole mass spectrometry. Based on preliminary analysis performed during the TA they decided to conduct one extra (supplementary) experiment to explore the possibility of forming carbon and sulfur-bearing molecules by implanting high-energy carbon (750 keV) ions into hydrogen sulfide (H2S).
The preliminary analysis does not indicate the formation of thiols in the investigated hydrocarbon ices as a result of high-energy sulfur ions implantation. However, several new absorption bands appeared in the
spectra of all irradiated hydrocarbons, indicating the formation of various alkanes and alkenes. The emergence of a prominent band around ~1600 cm-1 could suggest the presence of carbon in an amorphous form.


22-EPN3-028 – Energetic Ion Processing of Pyrene Ice

22-EPN3-028 – Energetic Ion Processing of Pyrene Ice

Visit by Alicja Domaracka (CIMAP-CNRS, France) and Anna Bychkovato (Normandie Université, France) TA2.11 Atomki Ice Chamber for Astrophysics / Astrochemistry (ICA) (Hungary).
Dates of visit: 16-20 October 2023

Report Summary: Over the last decades it became clear that we live in a “molecular universe”. Carbon forms the basis of the majority of the molecular species that so far have been identified in space. Although small carbon-based molecules, like CO and CO2, are some of the most abundant molecules in space, only a small fraction of the carbon is expected to be locked up in such species. It was proposed that a large portion of the interstellar carbon, up to 20%, is built in polycyclic aromatic hydrocarbons (PAHs) and fullerenes. There is a clear lack of information about interaction of energetic ions with pyrene in the solid phase.

In January 2022, Alicja Domaracka (CIMAP-CNRS, France) and Anna Bychkovato (Normandie Université) performed irradiations of pure pyrene 20 K by protons and carbon ions at the ATOMKI facility. Within the present TA, they studied pure pyrene ice at 20K irradiated with 6.4 MeV S3+, 4 MeV S2+, 2,4 MeV C2+, 400 KeV He+, 800 keV He+ and 800 keV H+ ion beams, respectively. In particular, we are interested in learning how the pyrene destruction cross sections depend on the projectile parameters (atomic number, energy).


20-EPN2-116: Hypervelocity Impacts for DISC Calibration

20-EPN2-116: HIDISCC (Hypervelocity Impacts for DISC Calibration)

Visit by Vincenzo Della Corte, Osservatorio Astronomico Capodimonte Napoli, INAF (Italy), to TA2.7 Light Gas Gun Laboratory, University of Kent (UK)
Dates of visit: 27-29 March 2023

Report summary: The Comet Interceptor space mission is to launch in 2029 to study a dynamically new comet. Two of the three spacecraft involved will host copies of the Dust Impact Sensor and Counter (DISC), which will measure the physical properties of cometary dust. The spacecraft’s velocity (7-70 km/s) will result in hypervelocity dust impacts on DISC. Combined with the range of dust particle sizes, this will create a wide range of impact momentum (10-11–10-3 kg/m/s). To cover the upper part of the momentum range, DISC calibration will be performed with hypervelocity simulated impacts induced by lasers. To perform DISC characterization and calibration in the lower momentum range, we carried out experiments at the Light Gas Gun Impact Facility at the University of Kent (UK).

To calibrate DISC and check the sensing element formed by the aluminum plate and the piezoelectric transducers:

  • We performed 9 shots at the Light Gas Gun Impact Facility at the University of Kent. We used different particle sizes and materials and different speeds, utilising different approaches, i.e. single particles with diameters down to 400 nm and buck-shots of a mixture of minerals and very light hollow spheres.
  • The signals from the piezoelectrics will be used to verify DISC estimated performance and enable a generally-valid impact sensor calibration procedure.

All 9 shots provided signals, this was for both single impacts and multiple buck- shot impacts. The results of the experiment confirmed the capability of the instrument to measure the momentum of particles impacting in the hypervelocity range.


20-EPN2-098: Constraining the Thermal History of Water-Rich Asteroids Using Noble Gas Analysis of Heated CM Chondrites

20-EPN2-098: Constraining the Thermal History of Water-Rich Asteroids Using Noble Gas Analysis of Heated CM Chondrites

Visit by Ashley King and Helena Bates (Natural History Museum, UK) to TA2.15 ETH Zurich Geo- and Cosmochemistry Isotope Facility (Switzerland).
Dates of visit: 28 November – 08 December 2022

Report Summary:

In this TA visit, the team investigated the abundance and isotopic composition of noble gases (He – Xe) in CM chondrites that record both aqueous and thermal metamorphism. These unusual meteorites are likely good analogues for the types of material found on the surfaces of primitive C-type asteroids; however, the timing and mechanism of the metamorphism remains unknown.

The team measured He – Xe in five CM chondrites that experienced peak metamorphic temperatures of <300°C to >750°C using stepped-heating and the “ALBATROS” mass spectrometer at the ETH Zürich Geo- and Cosmochemistry Noble Gas Laboratory. Preliminary results show that the concentrations of 4He and 22Ne are depleted in the lowest temperature steps (300 and 450°C) for all samples, consistent with degassing during (a) metamorphic event(s). Peaks in the concentration of both light and heavy noble gases in the 660°C and 800°C steps agree with previous estimates of metamorphic temperatures based on mineralogy and H2O loss. Isotopic compositions are mainly a mixture of primordial (so-called Q/HL) and cosmogenic components. In addition, EET 96029 and WIS 91600 contain a trapped solar wind component, suggesting that these meteorites may have been heated by impacts during residence in the asteroid regolith. Comparison of the data to unheated CM chondrites will be used to further constrain the thermal history of C-type asteroids in the early Solar System.

Read the full scientific report with kind permission by Ashley King and Helena Bates.


22-EPN3-019: Investigation of Ceres Bright Spots

22-EPN3-019: Investigation of Ceres Bright Spots – VIS-NIR Spectral Simulation of Haulani bright Areas by Means of Spectral Analysis on Produced Analogue Mixtures

Visit by Fabrizio Dirri and Giuseppe Massa (INAF-IAPS, Italy) to TA2.8 CSS (Cold Surfaces Spectroscopy) at IPAG (France).
Dates of visit: 22 May – 03 June 2023

Report Summary: In this project different bright areas of Haulani crater (i.e. Southern floor and Central Crater Peak, named ROI3 and ROI1) on Ceres have been studied by producing different analogue mixtures starting from previous results and comparing them with Dawn VIR data. The end-members have been identified based on previous studies (Tosi et al. 2018, Dirri et al. 2022) and the analogue mixtures have been produced with grain size 50-100 µm. The two initial mixtures, i.e. SF1 and CCP_#1 have been acquired in the VIS-NIR spectral range (0.4-4.5 µm) at T environment. The Band Center, Band Depth and FWHM of absorption bands at 2.7, 3.1, 3.4 µm, spectral slope (1.2-1.9 µm range) and reflectance level at 2.1 µm of the produced SFs and CCPs mixtures have been analysed and then compared with VIR data.

The best analogues are the SF_#5 and CCP_#6 mixtures and their spectra have been acquired at low temperatures, i.e. from 190K to 230K, similar to Haulani base temperature by using Cold Spectroscopy Facility (CSS) (IPAG, France). These mixtures exhibit values for the 2.7BD (Antigorite, Illite), 3.1BD (NH4-Montmorillonite) and 3.4 BD (NaCO3) similar to Haulani ROI3 and ROI1. In particular, different dark components have been used (i.e. magnetite plus carbon black) with the aims of better reproducing the Haulani spectral slope and reflectance level. Different carbonates mix involving trona, dolomite, hydrous and anhydrous natrite have been studied to assess their contribution to 2.7 µm spectral band and the three minima at 3.33, 3.42, 3.52 µm of Haulani ROI3.


22-EPN3-038: Asteroidal source(s) of L chondrites and its collisional evolution

22-EPN3-038: Asteroidal source(s) of L chondrites and its collisional evolution – U,Pb geochemistry of phosphates in meteorite Antonin.

Visit by Monika Kusiak (Institute of Geophysics Polish Academy of Sciences (IG PAS), Poland) and Agata Krzesinska (University of Oslo) to TA2 Facility 26 – KBSI Sensitive High Resolution Ion MicroProbe / SHRIMP-IIe/MC (South Korea).
Dates of visit: 12-23 May 23

Report Summary: The main goal of the visit was to conduct in-situ U-Pb geochronological study of phosphate minerals in the Antonin L chondrite. Fall of the Antonin, on 15th July 2021, was recorded by European Fireball Network, and this recording led to reconstruction of the pre-atmospheric orbit of meteoroid. The orbital parameters of the Antonin differ from reconstructed orbits of other L chondrites, but suggest it was sourced from the inner asteroid belt. To track the orbit to the parent body, it is important to understand dynamic collisions experienced, which are recorded in minerals of the meteorite. U-Pb dating allows to decipher details on events that led to resetting of phosphates.

During the visit to KBSI facility, we collected SHRIMP (Sensitive High-Resolution Ion MicroProbe) analyses within multiple apatite and merrillite grains. Initial U-Pb results show minor discordance of ages of phosphates, indicating a mild collision after the crystallization of the minerals. The timing of reset event cannot be inferred with high precision, but it likely occurred between 500–100 Ma.

Additionally, formation of phosphates can be well constrained from collected data at ca. 4450 Ma. This age implies that phosphates formed/recrystallized in response to a collision as impacts were the only source of heat after cessation of accretional activity. Altogether, the results suggest two collisions in the evolution of parent body and will be combined with further data to pinpoint key events in dynamical evolution of parent body of L chondrites.


22-EPN3-008: U/Pb-Dating of the Youngest Eclogites on Earth

22-EPN3-008: U/Pb-Dating of the Youngest Eclogites on Earth.

Visit by Linus Streichers and Willem van Westrenen (Vrije Universiteit Amsterdam, Netherlands) to TA2 Facility 26 – KBSI Sensitive High Resolution Ion MicroProbe / SHRIMP-IIe/MC (South Korea).
Dates of visit: 05 April 2023 – 01 May 23

Report Summary: A total of 184 U-Pb-ages of zircon from eclogites from Sulu-Dabie UHP metamorphic belt (China), the D’Entrecasteaux Islands (Papua New Guinea) and the Western Gneiss Region (Norway) were successfully determined using the SHRIMP IIe/mc of the Korean Basic Science Institute.

Using the concordia method, we could identify a concordant age of the peak metamorphism of eclogite from Sulu-Dabie of ca. 240 Ma. In addition, a discordant age of around 720 Ma could be identified, which may reflect the age of inherited, magmatic zircon cores. The zircon from the D’Entrecasteaux Islands revealed ages below 8 Ma, which is younger than ages previously measured on the same sample in a previous study. This makes this sample one of the youngest eclogites ever discovered on Earth’s surface. Zircons from the Western Gneiss Region reveal ages of three distinct events. With 1.5 Ga, the oldest age determined probably reflects the Precambrian formation of the UHP region, while ages of around ca.

900 Ma correspond with the Sveconorwegian orogeny. The youngest age found in Norway reflects the Scandian orogeny at an age of ca. 415 Ma. The age information obtained will help us to develop improved evolutionary models for the formation of UHP rocks by combining these ages with trace element data.


20-EPN2-057: A Zircon Provenance Study of the Kanye Basin (Botswana) to Constrain Terrestrial Geodynamics Across the Archaean-Proterozoic Transition

20-EPN2-057: A Zircon Provenance Study of the Kanye Basin (Botswana) to Constrain Terrestrial Geodynamics Across the Archaean-Proterozoic Transition.

Virtual visit by Denice Borsten and Jochem Sikkes (Vrije Universiteit Amsterdam, Netherlands) to TA2 Facility 26 – KBSI Sensitive High Resolution Ion MicroProbe / SHRIMP-IIe/MC (South Korea).
Dates of visit: 23 September 2021 -17 February 2022

Report Summary: This study investigates the Neoarchaean to Paleoproterozoic Transvaal Supergroup sedimentary sequence in Botswana that formed in the centre of the Kaapvaal Craton during the early oxygenation of the atmosphere. We used U-Pb dating on magmatic and sedimentary zircons from throughout the sedimentary sequence to determine the tectono-magmatic evolution of the hinterland basement. This approach constrains regional crustal growth, uplift and erosion events and establishes if additional cratons were in the hinterland, e.g. Pilbara. Knowledge of zircon provenance will allow critical comparison to known tectonic scenarios, e.g. Alpine style molasse basin and any potential change in Neoarchaean tectonics by considering erosion and crustal growth-reworking. The geochronology results help evaluate spatial and temporal variations in depositional environments associated with oxygenation of the atmosphere. Results indicate that the age of the basement, Gaborone Granite and the Kanye volcanic are indistinguishable (2768.9 ± 6.0 Ma). Sediments deposited from 2.642 Ga to 2.550 Ga are also dominated (> 90%) by zircons of ~2.77 Ga. This implies that there was a major crustal growth event in the Kanye region at 2.77 Ga that included minimal crustal reworking. Erosion products to the Kanye Basin are derived from this juvenile crust throughout the Archaean and Proterozoic until > 2.0 Ga.  Only then are older and younger basement rocks recorded in the sedimentary sequence. This region of the planet yields no evidence of a major tectono-magmatic event associated with the oxygenation of the atmosphere. 


22-EPN3-060: A new apparatus for measuring the electrical charge of volcanic ash particles

22-EPN3-060: A new apparatus for measuring the electrical charge of volcanic ash particles

Visit by Allan Fries, University of Geneva (Switzerland), to TA2.4 Planetary Environment Facilities (PEF), AU (Denmark)
Dates of visit: 02-11 August 2023

Report summary: The electrical charge carried by volcanic ash particles is known to play a crucial role in the formation of aggregates, which modulate the atmospheric transport and deposition rate of volcanic ash. However, direct field measurements of these charges remain rare, and more investigations are required to better comprehend both charge generation and aggregation mechanisms. This study aimed at building and testing a portable device to quantify the charge of individual volcanic ash particles and aggregates using a Through-Type Faraday Cage (TTFC) connected to a charge amplifier circuit capable of detecting the very small voltages induced by charged particles entering the TTFC.

After building the apparatus, 187 tests were performed, using different quantities and types of particles, as well as varying the measurement technique. First results show that the newly built device is capable of measuring charges down to 0.1 pC and that measurements agree well with alternative estimations obtained by directly integrating the current generated in the TTFC over time.

Beside the charge, results also suggest that the device can be used to obtain the particle settling velocity, based on the duration of the voltage signal. Few additionnal tests are now required to detect smaller particles (i.e., smaller charges) and the instrument will then be used for field analysis and laboratory experiments.

Read the full scientific report, with kind permission from Allan Fries.