the kasian volcanic body is located in the eastern margin of the zagros thrust belt, close to the sanandaj-sirjan metamorphic zone. these volcanic rocks are mainly composed of andesite and andesite-basalt rocks with porphyritic, hypocrystalline porphyritic, hyalo-porphyritic and hyalo-microlitic porphyritic textures. analyses of the distributions of major, rare earth and trace elements reveal a...

In recent years, a rapidly expanding database, especially in sensitive high-resolution ion microprobe (SHRIMP) geochronology, has led to signifi cant advances in understanding of the Precambrian tectonic evolution of the Grenville Province, including its Adirondack outlier, and the Mesoproterozoic inliers of the Appalachians. Based upon this information, we review the geochronology and tectonic...

Chemical investigations of marine sponges from the genus Hyrtios has yielded a predominance of scalarane-type sesterterpenes.' We have previously isolated heteronemin and the new 12-epi-heteronemin as representatives of this class of sesterterpenes, from the marine sponge Hyrtìos erecta collected in New Caledonia? However, both scalarane-type sesterterpenes and those of the manoalide family hav...

Many animals use tools, but their understanding of physical forces or causal relations is unclear (1, 2). Primates are considered the most versatile and complex tool users, but observations of New Caledonian crows (Corvus moneduloides) (3–5) raise the possibility that these birds may rival nonhuman primates in tool-related cognitive capabilities. We report here an experiment inspired by the obs...

this paper presents evidence on mesozoic inversion of basin bounding faults within the taleqan-gajereh-lar paleograben (tglp) in central alborz range. for this purpose, well documented stratigraphy data across the tglp together with the new acquired structural data on the geometry and kinematics of the paleograben basin bounding faults are utilized. the tglp has evolved through the early and mi...