Results 91 to 100 of about 22,653 (256)

Timing of Dike and Sill Emplacement in the Inner Aureole of the Alta Stock, Utah Determined by Zircon and Monazite Petrochronology

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 5, May 2025.
Abstract Detailed geochronology from two compositionally distinct generations of dikes and sills intruded into the Alta metamorphic aureole, north‐central Utah, complement previous geochronologic studies from the Alta stock, providing information on the timing of magmatism and the nature of emplacement.
C. J. Beno, M. A. Stearns, J. R. Bowman, J. M. Bartley, D. P. Fernandez, A. R. C. Kylander‐Clark   +5 more
wiley   +1 more source

Seismic anisotropy of Precambrian lithosphere : Insights from Rayleigh wave tomography of the eastern Superior Craton [PDF]

, 2017
The seismic data used in this study are freely available from the CNDC (Canadian National Data Centre for Earthquake Seismology and Nuclear Explosion Monitoring) and IRIS DMC (Data Management Center) via their data request tools.
Lee S., Nolet G., Sato Y., Snieder R., Vinnik L., Wardle R. J.   +5 more
core   +2 more sources

Relict Back‐Arc Basin Crustal Structure in the Western Greater Caucasus, Georgia

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 5, May 2025.
Abstract Back‐arc basins frequently form within subduction zones, creating sources of lithospheric weakness that can accommodate subsequent compressional deformation. The crustal structure of these basins, including whether they contain extended preexisting crust and/or new crust formed by seafloor spreading, can thus exert a major influence on strain ...
Dylan A. Vasey, Eric Cowgill, Jill A. VanTongeren, Catherine O. Anderson   +3 more
wiley   +1 more source

Geochemistry and Geochronology of A‐Type Intermediate‐Felsic Rocks in NW Himalaya, Pakistan: Implications for Petrogenesis and Tectonic Evolution of Northern Gondwana

Geochemistry, Geophysics, Geosystems
Igneous intrusives in northern Pakistan can provide valuable insights into pre‐Himalayan metaluminous to peraluminous magmatism along the northern boundary of the supercontinent Gondwana and its potential tectonic significance.
Musa Khan, Huan Li, Thomas J. Algeo, Asad Khan, Michael W. Förster, Zaheen Ullah   +5 more
doaj   +1 more source

Avanços na caracterização das estruturas geológicas em subsuperfície da provincia uranífera lagoa real (ba) a partir de dados aerogeofísicos [PDF]

arXiv, 2011
In this work we present results of a recent re-evaluation of airborne magnetometric and gamma spectrometric data of the uranium province of Lagoa Real (BA), acquired under the project S\~ao Timoteo. The main purpose is to provide new insights into the magnetic and radiometric characteristics of the structural units in this region, derived from a ...
arxiv  

Heterogeneous Mantle Metasomatism Controlled by Continental Subduction: Evidence From Post‐Collisional Mafic Rocks in the North Qaidam Orogen

Geochemistry, Geophysics, Geosystems, Volume 26, Issue 5, May 2025.
Abstract Post‐collisional mafic rocks not only record geodynamic processes at the end of the orogenic cycle but also retain various clues regarding preceding interactions between subducted slabs and mantle wedges. However, the latter and related indicators have often been overlooked; in particular, how the continental crust interacts with the mantle in
Xiangyu Gao, Shengyao Yu, Yu Qi, Lintao Wang, Chuanzhi Li, Xiaocong Jiang, Xingzhou Jiang, Yang Yu   +7 more
wiley   +1 more source

The Lages diatremes: mineral composition and petrological implications

Anais da Academia Brasileira de Ciências, 2007
Chemical data of heavy minerals from Lages diatremes in southern Brazil have been studied with the aim of characterizing the sample source(s). Three groups of minerals are recognized: I) aluminian-chromian pyroxene, pyrope garnet and chromian spinel ...
Giancarlo Barabino, Celso B. Gomes, Gianbosco Traversa   +2 more
doaj   +1 more source

A Mechanistic Look at the Amphibolitization of Mafic Crust: Insights From the Kråkeneset Gabbro Body, Western Gneiss Region, Norway

Journal of Metamorphic Geology, Volume 43, Issue 4, Page 385-405, May 2025.
ABSTRACT Fluid–rock interactions play a key role in the formation, evolution and recycling of the Earth's crust. For fluids to infiltrate rocks and enable and sustain fluid‐mediated mineral transformations, fluid pathways are required. In this study, we examined the potential mechanisms of formation of such pathways via detailed mineralogical ...
Saskia Grund, Timm John, Johannes C. Vrijmoed, Håkon Austrheim, Torgeir B. Andersen   +4 more
wiley   +1 more source

Equilibrium Silicon Isotope Fractionation in Eclogites and Granites Constrained by Single Crystal X‐Ray Diffraction and the Force Constants Approach

Geophysical Research Letters, Volume 52, Issue 8, 28 April 2025.
Abstract Using our recently developed X‐ray diffraction based force constants approach, we have determined the equilibrium Si isotope fractionation between omphacite/garnet, quartz/kyanite, and quartz/zircon at temperatures relevant to the petrogenesis. We find that Na strongly affects the Si isotope fractionation between omphacite and garnet.
Dongzhou Zhang, Jingui Xu, Przemyslaw K. Dera, Bin Chen, Ming Chen   +4 more
wiley   +1 more source

Field Utilization and Analysis of AIS 128-channel Imagery Using Microcomputers: Application to Yerington, Nevada Field Area [PDF]

, 1985
Geologists in exploration need to be able to determine the mineral composition of a given outcrop, and then proceed to another in order to carry out the process of geologic mapping.
Lanz, K., Lyon, R. J. P.
core   +1 more source