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The rocks of the Jasra intrusive complex (Shillong Plateau, northeastern India) include phlogopite clinopyroxenites (with olivine or perovskite relics), alkali gabbros/monzodiorites, syenites and nepheline syenites. They have a potassic affinity (Na2O/K2O ∼1), and their mineralogy is dominated by clinopyroxene with which phlogopite, olivine, amphibole, feldspars, feldspathoids, oxides, orthopyroxenes, perovskite, titanite and other accessory phases are variably associated. The Jasra intrusive rocks are cumulates derived from at least two distinct magmatic liquids. The potassic affinity of the Jasra rocks differs from the nearby Sung Valley ijolitic-carbonatitic complex and from the ultrapotassic lamproitic rocks of the Damodar Valley, which are of approximately the same age. This suggests major variability in the mantle sources of small-volume alkaline volcanism in the Early Cretaceous of northeastern India.

The Massif d'Ambre is the largest stratovolcano (similar to 2500 km(2)) in the Cenozoic igneous province of northern Madagascar. It is broadly elongated in a N-S direction and is formed by hundreds of lava flows, plugs, spatter cones, tuff rings, pyroclastic flows, and pyroclastic fall deposits. New Ar-40-Ar-39 age determinations for lavas of Massif d'Ambre and Bobaomby Peninsula (the northernmost tip of Madagascar) yield ages of 12.1 +/- 0.2 Ma and 10.56 +/- 0.09 Ma. These ages indicate that at least part of the volcanic activity of the Bobaomby Peninsula occurred later than the beginning of the activity of the Massif d'Ambre. The volcanic products of Massif d'Ambre are mildly to strongly alkaline (with sodic affinity) to tholeiitic with very limited amounts of evolved magmas. The mafic rocks have compositions similar to those of primitive mantle-derived magmas (MgO >10 wt%, Cr and Ni >400 and >200 ppm, respectively). The strongly alkaline suite shows a liquid line of descent from basanite to phonolite, dominated by fractional crystallization of clinopyroxene and olivine. The mafic rocks (basanites, alkali basalts, transitional and tholeiitic basalts) have Zr/Nb (2.4-5.8), Ba/Nb (7-24) and La/Nb (0.7-1.1) ratios typical of incompatible element-rich within-plate basalts. The primitive mantle-normalized incompatible element patterns of the Massif d'Ambre mafic rocks are characterized by peaks at Nb and troughs at K, and are identical in shape and absolute abundances to those of the Nosy Be and Bobaomby (Cap d'Ambre) basanites. The range of (La/Yb)(n) ratios (9-24) indicates that the Massif d'Ambre primitive compositions are the product of variable degrees of partial melting (4%-12%) of a broadly similar and slightly incompatible element-enriched mantle source. Initial Sr-87/Sr-86 and Nd-143/Nd-144 ratios of alkali basalts and basanites vary from 0.70326 to 0.70359 and 0.51279 to 0.51286, respectively. Alkali basalts and basanites have little variation in Pb-206/Pb-204 (19.073-19.369), Pb-207/Pb-204 (15.613-15.616), and Pb-208/Pb-204 (39.046-39.257). This range is well within that of Sr-Nd-Pb isotope values of the basanites of the Nosy Be Archipelago, thus again confirming substantially similar source compositions throughout northern Madagascar.

A multidisciplinary study has been conducted on 109 intrusive sheets of Stromboli. The relation between sheet injection conditions with the magmatic and structural variations of the volcano, and the parameters governing the preferential intrusion geometry inside the volcano in a time perspective have been determined. During its subaerial activity (the last 100 ka) Stromboli experienced periods of extrusive growth and sheet intrusions, alternated to caldera and lateral collapses of the NW Sciara del Fuoco flank. The sheet intrusions, similar to the extrusive rocks, span a large compositional range from calc-alkaline to potassic, through high-K calc-alkaline and shoshonitic series. The most evolved compositions of the effusive rocks, however, have not been found as intrusions, whereas some mafic and basic magmas of sheets were never erupted. The repeated time change of location of the intrusions from Strombolicchio to the NE-SW trend passing trough the inferred Paleostromboli summit cone and the southern flank could represent the expression of the shift of the magma chamber towards the southeast, and the subsequent onset of a clear NE-SW-elongated magma chamber located along the main Stromboli weakness zone. The Stromboli evolution in the last 100 ka has been characterized by the persistent N 10-55° E intrusion direction, which reflects the influence of the edifice's state of stress on the magma feeding paths. After 13 ka ago, sheets mainly intruded along to the sector collapse scarps in a circum-amphitheatre geometry, which has been demonstrated to be influenced by the new cone morphostructure and not by different magma rheological characters. © 2008 Elsevier B.V. All rights reserved.

The St Mary9s Islands (southwestern India) expose silicic volcanic and sub-volcanic rocks (rhyolites and granophyric dacites) emplaced contemporaneously with the Cretaceous igneous province of Madagascar, roughly 88–90 Ma ago. The St Mary9s Islands rocks have phenocrysts of plagioclase, clinopyroxene, orthopyroxene and opaque oxide, moderate enrichment in the incompatible elements (e.g. Zr = 580–720 ppm, Nb = 43–53 ppm, La/Yb n = 6.9–7.2), relatively low initial 87 Sr/ 86 Sr (0.7052–0.7055) and near-chondritic initial 143 Nd/ 144 Nd (0.51248–0.51249). They have mineral chemical, whole-rock chemical and isotopic compositions very close to those of rhyolites exposed between Vatomandry–Ilaka and Mananjary in eastern Madagascar, and are distinctly different from rhyolites from other sectors of the Madagascan province. We therefore postulate that the St Mary9s and the Vatomandry–Ilaka–Mananjary silicic rock outcrops were adjacent before the Late Cretaceous rifting that split Madagascar from India. If so, they provide a valuable tool to check and aid traditional Cretaceous India–Madagascar reconstructions based on palaeomagnetism, matching Precambrian geological features, and geometric fitting of continental shelves. Supplementary material: Mineral analyses, mass-balance calculations and locality information are available at http://www.geolsoc.org.uk/SUP18332.

The ancient town of Allifae (modern Alife) represents one of the most interesting settlements of the Northern Campania area that, together with the ancient city of Cales, was a thriving production centre of pottery. Excavations carried out inside the city wall, near the south gate, the so-called Porta Fiume, unearthed a huge dump of thin walled ware where the most abundant forms were cups and beakers, decorated with grooves or rouletting. The dump has been dated Augustan/ early Tiberian age (20 b.C.- 20 AD) and the thin walled vessels found can be identified with similar wares from Allifae, Cubulteria, Caiatia and perhaps Neapolis. Horace in his Sermones (II, 8,39) cited the Allifana beakers (described as fictiles ac subtiles by a Horace scholiast) and they could possibly be identified with the thin walled wares produced in Allifae. If this the case, then the thin walled vessels produced in Allifae were known in Rome as early as the end of I century B.C. In order to investigate and characterise the Allifae thin-walled pottery, twenty-one samples were selected and mineralogical-petrographic analyses (OM, XRPD, XRF and SEM/EDS) were carried out. The clayey raw material used was a low-CaO alluvial clayey deposit from the Middle Valley of the Volturno River. The potters probably handled the sediment by a levigation process in order to remove the coarser grains, and making the clay suitable to produce such thin walls. Comparison with other regional production of thin-walled pottery allowed us to strictly distinguish the Allifana beakers.