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The pumice volcanic samples could have possible connections to the evolution of life and give us insight about their bio-geochemical processes related. In this regard, the samples from the volcanic eruption from La Restinga (El Hierro, Spain) in 2011 have been mainly studied by means of Raman spectroscopy. The research also includes analysis of XRD, Scanning Electron Microscopy and Optical Microscopy to support the Raman analysis. The results show that the Raman methods and mineral analyses are in strong agreement with the results obtained from other authors and techniques. The internal white foamy core (WFC) of the studied pumice samples shows amorphous silica, Fe-oxides, Ti-oxides, quartz, certain sulfates, carbonates, zeolites and organics. On the other hand, the external part (dark crust – DC) of these samples mainly presents primary-sequence mineralogy combined with some secondary alteration minerals such as olivine, feldspar, pyroxene, amorphous silica, and Fe-oxide. Raman spectroscopy detected other minerals not yet reported on these samples like barite, celestine and lepidocrocite. Also, the different chemometric and calibration methods for Raman spectroscopy in elemental composition, mineral classification and structural characterization has been successfully applied. From the astrobiological perspective, the research was also complemented with comparisons to other similar samples from terrestrial analogs. The main consideration was taking into account the proposed hypothesis regarding the potential behavior of the pumice as a substrate for the evolution of life. Furthermore, the detailed analysis from La Restinga eruption is coherent with the mineral phases and processes discussed from previous literature. The white internal part fulfills the conditions to work as an organic reservoir, confirmed by the detection of organic matter and selected minerals that could be used as energy sources for bacterial communities. The external layers of the samples work as a shielding layer to protect the organics from decay in extreme conditions. Finally, here we have demonstrated that the characteristics and advantages of Raman spectroscopy could help to assess and understand the possible biogenicity and alteration processes of any geological sample to be found on Mars., The work was supported by the MINECO of Spain through the project the ESP2014-56138-C3-2-R for the development of the Raman instrument for the ESA-ExoMars Mission. The first author would like to thanks to the Ontario Centres of Excellence (OCE) for the TalentEdge Funding at York University.

This paper investigates the relationship between the stiffness and rutting resistance of hot-mix asphalt. Ten different types of hot-mix asphalt were examined. The Superpave mix design method was utilized to produce nine mixes; the remaining mix was designed using the Marshall method. The asphalt mixes were tested for stiffness and rutting resistance under the Centre for Pavement and Transportation Technology research program at the University of Waterloo. The stiffness was determined by the laboratory resilient and dynamic moduli tests. The dynamic modulus test was conducted at six different loading frequencies and five different temperatures. The rutting test was executed by the Hamburg Wheel Rut Tester and the French Laboratory Rutting Tester to obtain rutting depth. The regression analysis was performed to examine the relationships of resilient and dynamic moduli with rutting depth. The results of the regression analysis revealed that resilient modulus did not correlate well with rutting depth. In contrast, dynamic modulus showed strong correlation with rutting depth for a number of loading frequencies and temperatures. The strong relationship was observed at the higher temperatures of +46.1 oC and +54.4 oC. Moreover, the relationship between dynamic modulus and rutting depth was better for lower loading cycles/wheel passes applied in the rutting test. It was also noticed that dynamic modulus exhibited a better relationship with rutting depth obtained from the French Laboratory Rutting Tester. The overall findings indicate that the dynamic moduli obtained at 0.1–1.0 Hz and +46.1–(+54.4) oC are useful to predict the rutting resistance of hot-mix asphalt.