beecee Posted June 25, 2019 Posted June 25, 2019 https://phys.org/news/2019-06-santorini-volcano-terrestrial-analogue-mars.html The Greek island of Santorini is now one of the most popular tourist destinations in the Mediterranean, but 3,600 years ago it suffered one of the largest volcanic eruptions in recorded history. Among the material that was exposed, scientists have now found rocks similar to those of Mars. "In the Balos Cove, located to the south of the island, we have discovered basalts such as those that have been identified by the rovers on Mars and with properties similar to those of certain meteorites from the red planet and those of terrestrial rocks classified as Martian analogues," says Ioannis Baziotis, a researcher at the Agricultural University of Athens and co-author of the study, recently published in Icarus. more at link..... the paper: https://www.sciencedirect.com/science/article/abs/pii/S001910351830681X?via%3Dihub Santorini volcano as a potential Martian analogue: The Balos Cove Basalts: Αbstract The interpretation of geologic processes on Mars from sparse meteorite, remote sensing and rover data is influenced by knowledge gained from well-characterized terrestrial analogues. This calls for detailed study of candidate terrestrial analogues and comparison of their observable features to those encountered on the surface of Mars. We evaluated the mineralogical, geochemical, and physical properties of the Balos covebasalts (BCB) from the island of Santorini and compared them to Martian meteorites, Mars rover surface measurements, and other verified Martian analogues obtained from the International Space Analogue Rockstore (ISAR). Twenty rock samples were collected from the Balos cove area based on their freshness, integrity, and basaltic appearance in the field. Optical microscopy of BCB revealed a pilotaxitic to trachytic texture, with olivine and clinopyroxene phenocrysts in a fine groundmass of olivine, clinopyroxene, plagioclase, magnetite, and devitrified glass. All major minerals show normal zoning, including calcic plagioclase (An78–85 at the core and An60–76 at the rim), augite(En36-48Wo41-44Fs11–21), and olivine (Fo74–88). The dominant bands in the infrared-attenuated total reflectance (IR-ATR) spectra from BCB can be assigned to olivine (~875 cm−1), calcic plagioclase (~1130 cm−1), and augite (~970 cm−1). The whole-rock chemical compositions and mineralogy of the BCB are similar to published analyses of typical olivine-phyric shergottites and basalts and basaltic materials analyzed in Gusev and Gale craters on Mars. BCB porosity is in the range of 7–15% and is similar to the porosities of the ISAR samples. Although no terrestrial rock is ever a perfect match to Martian compositions, the differences in mineralogy and geochemistry between BCB and some classes of Martian samples are relatively subtle and the basalts of Santorini are as close a match as other accepted Mars basalt analogues. The Santorini site offers excellent field logistics that, together with the petrology of the outcrop, makes it a valuable locality for testing and calibration deployments, field training, and other activities related to current and future Mars exploration. 1
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