Cretaceous plutonic rocks of the southern Sierra Nevada batholith between latitudes 35.5°N and 36°N lie in a strategic position that physically links shallow, subvolcanic levels of the batholith to lower-crustal (~35 km deep) batholithic rocks. This region preserves an oblique crustal section through the southern Sierra Nevada batholith. Prior studies have produced large U/Pb zircon data sets f...

Biotite and K-feldspar Ar/Ar systems from the east-central Peninsular Ranges batholith near 33°N were affected by two distinct phases of Late Cretaceous rapid cooling. The 85-Ma biotite K-Ar isochron separates comparatively shallow rocks in the southwest that record earlier cooling (91–86 Ma) from deeper rocks in the northeast that record later cooling (78–68 Ma). Samples close to 85 Ma isochro...

The distribution of Selenium (Se) in the Jurassic-Cretaceous Mist Mountain Formation of southeastern British Columbia was documented in a previous study by Ryan and Dittrick (2001). As part of that study, complete sections of rock types, including coal seams were sampled, as well as various materials segregated by mining such as coarse refuse and solid tailings from tailings ponds. Preliminary ...

Large albitite bodies associated with explosive brecciation, fenite aureoles, intrusive carbonate rocks, olivine dolerites, and copper mineralization are described from the Dead Sea rift region in the south-eastern Sinai Peninsula. The main carbonate phases comprise breunnerite and dolomite with actinolite the main phase in the fenites. Field and isotopic evidence indicates that the intrusive c...

introduction the investigated area is situated in the south west of the khorasan razavi province along the north west of the lut block. different types of metal ore bodies along with non-metal deposits have already been documented in the lut block (karimpour et al., 2008). most of the study area is covered with granitoid rocks. metamorphic rocks with unknown age are present in the north of the ...

The Skeena Arch project was initiated in the 2000 field season as a follow up to work completed as part of the Nechako NATMAP project (MacIntyre and Struik, 1999). The main objective of this project is to define areas that have a high potent ia l for the discovery of volcanogenic massive sulphide and/or subaqueous hot spring deposits (Eskay Creek type) along the trend of the Skeena Arch, in cen...

In the area SW of Arak, intrusives are emplaced into metasediments of early Mesozoic age. The intrusive rocks vary in morphology, structure and mineralogy, and exhibit various degrees of alterations; Rb-Sr geochronological data have been obtained to constrain their timing. There are three different groups of granitic rocks in the area: (a) the Astaneh intrusion, consisting of granite, biotite g...

The geology of the Darien province of eastern Panama is presented through a new geologic map and detailed biostratigraphic and paleobathymetric analysis of its Upper Cretaceous to upper Miocene sediments. The sequence of events inferred from the stratigraphie record includes the collision of the Panama arc (the southwestern margin of the Caribbean plate) and South American continent. Three tect...