In this letter, we report the profiles (-160 samples) of løBe, 9Be, Zn in a Mediterranean sediment core spanning the last 60 kyr. We show the existence of a løBe peak, whose absolute age is estimated to be 34+3 kyr B P, based on its stratigraphic position between two tephra layers originating from two volcanic eruptions (Campanian Ignimbrite and Citara), dated by K-Ar, '*øAr-39Ar and methods. This peak is similar to the increase in the løBe concentration observed in Vostok and Dome C ice cores at the same age. The increase with approximately similar amplitude in both ice and sediment cores at different latitudes and hemispheres cannot be explained by changes in the archives. The present result supports the view of a well defined global enhancement of the løBe flux, related to an increase of the løBe production rate and not to a redistribution of the løBe fallout between different latitudes.

Abstract— A meteorite shower fell at Torino, Italy on 18 May 1988. Petrographic studies indicate that the stone is an H6 chondrite having features of moderate to severe shock. Chemical analyses of the meteorite are reported. Cosmic ray produced 3He, 21Ne and 126Xe yield an exposure age of about 48 Ma. The cosmic ray track densities in three fragments range between 1.8 to 5 × 105/cm2 suggesting about 99% mass ablation in the atmosphere. Twelve radioisotopes with half lives ranging between 5.6 days to 7.3 × 105 years have been measured with high precision (2 to 10%). Marginal signals were observed for several short‐lived nuclides and upper limits were obtained for the activity levels of eight radionuclides (24Na, 48Cr, 57Ni, 47Sc, 47Ca, 59Fe, 42Ar and 44Ti) some of which have not been hitherto detected in fresh falls. The data are generally consistent with the nuclide production by galactic cosmic rays when modulation due to the solar cycle is taken into consideration. The preatmospheric radius of the chondrite is estimated to be 20 cm, consistent with track densities and activity levels of 60Co, 26Al and other radionuclides.

High-K calc-alkaline and shoshonitic Oligocene volcanics of the Cover Series of the Sesia Zone occur within a volcano-sedimentary unit located in the internal part of the Sesia Zone in proximity of the Canavese Line. High-K calc-alkaline rocks are basaltic andesites to andesites (K 2 O from 2.0 to 2.6 wt%) with high alumina contents (19.2-20.3 wt% for basaltic andesites). These rocks are enriched in incompatible trace elements of low ionic potential (with Ba ranging from 920 to 1320 ppm, Rb/Sr = 0.11-0.17). High-field-strength elements (HFSE) are within the typical range of orogenic andesites, with Zr ranging from 150 to 180 ppm. Rare Earth Element patterns for high-K intermediate rocks are enriched in LREE (La/Yb ranging 15.2-16.0) and show a small Eu negative anomaly. Shoshonitic rocks are trachyandesites to trachydacites, with K 2 O ranging from 4.6 to 5.5 wt%. Alumina contents are lower than those of the high-K calc-alkaline rocks ranging from 14.8 to 16.8 wt%. When compared to calc-alkaline andesites, shoshonitic rocks show higher contents in incompatible elements (with Ba higher than 2500 ppm; Rb/Sr = 0.30-0.35; La/Yb = 26.2-28.8; Zr = 380-450 ppm). Thermobarometric data indicate that andesitic s.l. lavas of the Cover Series of the Sesia Zone started to crystallize their phenocrystic phases at pressures between 3.6-4.8 kbar, for temperatures ranging from 1,080 to 1,150 °C, for water contents of at least 2-2.7 wt%. Shoshonitic lavas crystallized at 2-2.6 kbar for temperatures of about 900 °C, and approaching water-saturated conditions. REE patterns and spiderdiagrams, together with Pearce element ratios, indicate comagmatism between the lavas and the rocks of the Valle del Cervo Pluton. In particular there is a close genetic link between the shoshonitic and the high-K calc-alkaline volcanic rocks. Geochemical modelling shows that both suites may derive from a common " parental calc-alkaline basalt " with variable enrichments in terms of incompatible elements and transition metals. This basalt has suffered a different degree of fractionation in the genesis of balsaltic andesites (with F = 0.29) and monzonites of the Valle del Cervo Pluton (F = 0.19). High-K calc-alkaline andesites may be obtained by fractional crystallization of basaltic andesites, whereas shoshonitic lavas result from fractional crystallization of a monzonitic parent. This suggests that these lavas represent a differentiated top of a magma chamber, whose remnants are now represented by the Valle del Cervo Pluton. This is also supported by comparison of the Sr-Nd isotopic signatures of both intrusive and volcanic rock suites (the latter ranging from 0.7094 to 0.71175 in measured 87 Sr/ 86 Sr, and 0.51120-0.51228 in measured 143 Nd/ 144 Nd). Calculated isotopic parameters (α Sm/Nd = 0.46-0.52, δ Sm/Nd = 0.23 to 0.26 calculated at 2 b.y., and present ε Nd =-7 to-8.5) indicate that parental basaltic magmas to the high-K calc-alkaline and shoshonitic rocks were derived by low degree of partial melting (5-7%) of a moderately enriched "eclogitic" m...

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