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Central European Geology
Authors:
Mir Ali Asghar Mokhtari
,
H. Moinvaziri
,
M. R. Ghorbani
, and
M. Mehrpartou

of Petrology 35 525 541 . Aghanabati , S.A. 2004 : Geology of Iran . — Geological Survey of Iran, 606 p

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) , the AH is part of the Bihor Autochthonous Domain and is exposed in a tectonic window within the Codru Nappe System. Limited contradictory information is available regarding the petrological character, metamorphic evolution and structural development of

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. Árkai , P. 1978 : A Kiskunhalas ÉK-i terület mezozoikumnál idõsebb metamorf és magmás képzõdményeinek szénhidrogénprognózist elõsegítõ ásványtan-kõzettani és geokémiai vizsgálata (Mineralogical-petrological investigation of the igneous and

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Abstract  

The activity of the Department of Geology, Petrology and Geochemistry University of Liège, Belgium, is discussed.

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Journal of Radioanalytical and Nuclear Chemistry
Authors:
J. Kučera
,
J. Novák
,
K. Kranda
,
J. Poncar
,
I. Krausová
,
L. Soukal
,
O. Cunin
, and
M. Lang

Abstract  

We determined 35 major, minor and trace elements in sandstone samples taken from building blocks of 19 Angkor temples and from an old and a new quarry using INAA. We also characterized the sandstone samples with conventional microscopy and electron microprobe analysis. Using cluster analysis, we found no straightforward correlation between the chemical/petrological properties of the sandstones and a presumed period of individual temples construction. The poor correlation may result either from the inherent inhomogeneity of sandstone or just reflect the diversity of quarries that supplied building blocks for the construction of any particular temple.

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: Evidence from peridotite xenoliths of the Kozákov volcano, Czech Republic . – Journal of Petrology, 59 / 12 , pp.  1 – 1 . Ackerman , L. , P

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The metamorphic basement of the Pannonian Basin consists of uplifted highs and deep sub-basins among them. One of the best-known highs is the so-called Szeghalom Dome, which is surrounded by less intensely explored ones. The eastern neighbour, the Mezõsas-Furta Dome (MFD), is studied in this paper. Based on detailed petrologic investigation, six main lithologies are distinguished for the MFD, which can be well compared to those described previously for the Szeghalom Dome. All these rock types (orthogneiss, mafic-ultramafic xenolith, granite, sillimanite-biotite gneiss, garnet-bearing amphibolite, amphibole-biotite gneiss) are classified into three main units based on different metamorphic and deformation history. Understanding their relative spatial position permitted the elaboration of geologic map and sections of the MFD

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Zurbriggen, R., 1996: Crustal genesis and uplift history of the Strona-Ceneri zone (Southern Alps): a combined petrological, structural, geochemical, isotopic and paleomagnetic study. - Unpublished Ph.D. thesis, University of Bern

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of the observed diagenetic events Discussion – Petrological characteristics of the main rock types Limestone Based on the core analysis, there

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Seismically Kutch peninsula is very active. The distribution of seismicity in Peninsular Shield region from 1902 to 2001 show 12 earthquakes of M ≥ 6. The energy ratio from Kutch basin to Deccan trap is 20:1 and from trap to rest of the shield is 5:1. The last one hundred years seismicity data show Kutch basin is seismically more active than Deccan trap and the rest of the Peninsular Shield. The maximum magnitude of earthquake in the Kutch region is 7.7. The generations of large earthquakes in the region are difficult to explain, as plate boundary does not exist. In order to understand the physical processes that are taking place in the region to generate such large events the detailed analyses of geophysical and geological data have been examined in the light of development of rift, subsidence of basin, vertical tectonics and recent geophysical findings. In such regions, petrologic model can provide better explanation for release of fluid that generates large earthquakes, sprouting of sands, liquefaction, and large number of aftershocks activities and direction of stresses for aftershock sequences. The presence of magma in the Kutch upper mantle could be derived from various geological (subsidence of basin, development of rift faults) and geophysical observations (high heat flow over Cambay region, prominent positive Bouguer gravity anomalies and low shear velocity in the upper mantle). The inspection of seismological data shows all the medium size to large earthquake have occurred in shear zone of large gravity gradients or along the four major faults of the region. In view of geological and geophysical observations, petrologic model is proposed for generation of earthquakes in the region. The number of aftershocks and direction of stresses in the focal region of aftershocks would depend on the direction of movement of fluid incursion in the focal region after the occurrence of the main events. The recent Bhuj earthquake also shows more than 3000 aftershocks from Jan 29 to April 15, 2001. The expanding swarm activity in the focal region and the direction of stresses derived from first motion data of aftershocks for focal depths 2 to 8 km, 8 to 25 km, and 25 to 38 km supports the proposed model. Also, shear wave tomography studies in this region have revealed low shear wave velocity in the upper mantle of Cambay from shallow depth to 200 km depth showing high temperature zone. The analyses reveal the presence of conducting fluid in the focal zone, which is the main cause for generation of medium size to large earthquake in the region.

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