Monazite-(Ce) and xenotime-(Y) were found in the metacherts (pumpellyite–actinolite-facies conditions: 3 ≤ P ≤ 4 kbars and 300 ≤ T ≤ 350°C) of the Monte Figogna Unit, Sestri–Voltaggio Zone, Liguria, in Italy, as scattered submillimetric grains in pelitic beds and as euhedral crystals in both millimeter-thick quartz veins and open fissures. Their composition is comparable to those of known occur...

Early Jurassic U-Pb age is obtained for both foliated and undeformed granites on Horseshoe Island, Antarctic Peninsula. Some microstructures in the granites/orthogneisses indicate high-temperature greenschist or low- to medium-temperature amphibolite facies deformation conditions. Additionally, a Late Cretaceous yielded gabbro intruding deformed granitoids.

, ABSTRACT Metabasaltic rocks in the Klamath Mountains of California with 'komatiitic' major element concentrations were investigated in order to elucidate the origin of the magnesian signature. Trace-element concentrations preserve relict igneous trends and suggest that the rocks are not komatiitic basalts, but im~at~re arc rocks and within-plate alkalic lavas. Correlation of 'excess' MgO with...

Two large-scale north-dipping, low-angle normal faults cut the Everest massif at the top of the High Himalayan slab in Nepal. The upper fault the Qomolangma Detachment, follows the north slope of Everest from above the ‘Yellow Band’ at c. 8500 m on the Southwest Face down to the Rongbuk glacier. On the south side of Everest this fault places unmetamorphosed Ordovician mudstones and limestones a...