Results 121 to 130 of about 1,782 (304)
Journal of Economic Geology, 2015 Introduction Hornblende-bearing gabbroic rocks are quite common in subduction-related magmatic suites and considered to represent magmatic differentiation process in arc magmas (Heliker, 1995; Hickey-Vargas et al., 1995; Mandal and Ray, 2012).
Seyed Masoud Homam
doaj
The secondary classification of unequilibrated chondrites [PDF]
arXivThe multiplication of decimal petrologic schemes for different or the same chondrite groups evinces a lack of unified guiding principle in the secondary classification of type 1-3 chondrites. We show that the current OC, R and CO classifications can be a posteriori unified, with only minor reclassifications, if the decimal part of the subtype is ...
arxiv
Ultrahigh Pressure Metamorphism: Cambridge Topics in Petrology
Eos, Transactions American Geophysical Union, 1996 The field of ultra‐high pressure metamorphism (UHPM) emerged only 12 years ago when microscopic relics of coesite were found in crustal rocks that had been metamorphosed during subduction related to continental collision. Coesite‐bearing metamorphic rocks were soon found elsewhere, and then metamorphic microdiamonds were discovered.
openaire +2 more sources
The Chamrousse Ophiolite (Western Alps, France): Relict of a Devono‐Carboniferous Ocean
Terra Nova, EarlyView.ABSTRACT The Chamrousse ophiolite (Western Alps, France) is one of the best‐preserved Variscan relicts of Cambro‐Ordovician oceanisation within the northern Gondwana margin. This study presents new in situ U–Pb isotope analyses on zircon grains from that ophiolite, revealing that the oceanic stage in Chamrousse has occurred 150 Ma later than estimated.
Maureen Gunia +6 more
wiley +1 more source
Towards OWL-based Knowledge Representation in Petrology [PDF]
arXiv, 2011 This paper presents our work on development of OWL-driven systems for formal representation and reasoning about terminological knowledge and facts in petrology. The long-term aim of our project is to provide solid foundations for a large-scale integration of various kinds of knowledge, including basic terms, rock classification algorithms, findings and
arxiv
Schist Belts of the Benin‐Nigeria Shield Reveal a Neoproterozoic History
Terra Nova, EarlyView.ABSTRACT Belts of metasedimentary rocks (schist belts) in the Benin‐Nigeria Shield (BNS) are investigated for the first time using U–Pb dating and Lu‐Hf isotope analysis of detrital zircons. We report maximum depositional ages that place their deposition firmly in the Neoproterozoic and link them with strata in the Dahomey Belt, the central African ...
Axel Hofmann +6 more
wiley +1 more source
Predicting Metamorphic Relation for Matrix Calculation Programs [PDF]
arXiv, 2018 Matrices often represent important information in scientific applications and are involved in performing complex calculations. But systematically testing these applications is hard due to the oracle problem. Metamorphic testing is an effective approach to test such applications because it uses metamorphic relations to determine whether test cases have ...
arxiv
Analysing Temporal Variations in Radon Concentrations: Identifying Trends and Changes
Terra Nova, EarlyView.ABSTRACT Radon is a well‐known precursor for geodynamic events such as earthquakes and volcanic tremors. Radon concentration variations in soil gas have been monitored worldwide, and extreme radon values have been identified as radon anomalies associated with geodynamic events.
Mutlu İçhedef +3 more
wiley +1 more source
Deformation history and nappe stacking in Rudabánya Hills (Inner Western Carpathians) unravelled by structural geological, metamorphic petrological and geochronological studies of Jurassic sediments [PDF]
, 2009 Szilvia Kövér +5 more
openalex +1 more source
Terra Nova, EarlyView.ABSTRACT Mylonites and pseudotachylytes play a crucial role in defining the rheology of extending continental crust. In this context, determining the age of brittle‐ductile deformation is fundamental to understanding the rifting evolution stages. Here, we investigate the Premosello Shear Zone, an extensional structure of the Ivrea‐Verbano lower crust ...
Stefania Corvò +3 more
wiley +1 more source