voluminous quaternary extrusive rocks, associated with widespread volcanic activities, occur in the northwestern iran and across the turkish-iranian plateau. field and petrographic studies reveal that these volcanic rocks, consisting of basalt to trachyandesite, occur as lava flows, columnar basalts, and cinder cones in three distinct areas of northern (bazergan-maku-burlan), middle (chalderan)...

Abstract China has a rich record of Holocene volcanism that is relatively little known outside the country. It encountered in large stratovolcanoes NE, linked to subduction Pacific plate (e.g. Changbaishan), smaller volcanoes on Tibetan margin, associated with collision India and Eurasia Tengchong, Ashishan), more isolated centres, possibly resulting from mantle upwelling Hainan island). This m...

The southern part of the West African Craton includes Baoulé-Mossi Domain, world’s premier Paleoproterozoic gold province (~10,000 metric ton endowment). Structural, metamorphic, and geochronological data suggest mineralisation occurred during three episodes that span much Eoeburnean Eburnean orogenic cycles. rare skarn-hosted deposits formed between ca. 2200 2135 Ma repeated volcanism, plutoni...

In Africa volumetrically minor, mid-plate volcanic rocks of Cenozoic age are concentrated in areas affected by Pan-African (500 _+ 150 Ma) crustal reactivation, and are virtually absent from cratonic areas. We interpret this as indicating that Pan-African areas are underlain by fertile lithospheric mantle and cratons by depleted lithospheric mantle, and propose a model to explain both the distr...

Petrologic analysis of the lunar surface is critical for determining lunar formation and evolution. Here, we report the first global petrologic map that includes the five most important lunar lithological units: the Ferroan Anorthositic (FAN) Unit, the Magnesian Suite (MS) Unit, the Alkali Suite (AS) Unit, the KREEP Basalt (KB) Unit and the Mare Basalt (MB) Unit. Based on the petrologic map and...

1019 eology, November 2007; v. 35; no. 11; p. 1019–1022; doi: 10.1130/G24141A.1; 3 fi gures; 1 table; Data Repository item 2007250. © 2007 The Geological Society of America. For permission to copy, contact Copyright Permissions, GSA, or [email protected]. ABSTRACT We report oxygen isotope compositions of phenocrysts and U-Pb ages of zircons in four large caldera-forming ignimbrites and pos...

Geophysical data have led to the interpretation that Beta Regio, a 2000×25000 km wide topographic rise with associated rifting and volcanism, formed due to the rise of a hot mantle diapir interpreted to be caused by a mantle plume. We have tested this hypothesis through detailed geologic mapping of the V-17 quadrangle, which includes a significant part of the Beta Regio rise, and reconnaissance...

We review new advances in volcano–ice interactions on Mars and focus additional attention on (1) recent analyses of the mechanisms of penetration of the cryosphere by dikes and sills; (2) documentation of the glacial origin of huge fan-shaped deposits on the northwest margins of the Tharis Montes and evidence for abundant volcano–ice interactions during the later Amazonian period of volcanic ed...

In the Central IranianVolcanic Belt (CIVB), north-west of Shahre-Babak, in the area of Javazm, Dehaj and khabr, about 60 subvolcanic porphyritic dacitic to rhyodacitic domes (1-10 km2) are intruded into a variety of rock sequences from Mesozoic to Early Miocene in age. These rocks are a part of Dehaj-Sardoieh belt. The CIVB contains intrusive and extrusive rocks of Cretaceous-Quaternary age. Ge...