Results 21 to 30 of about 2,363 (234)

Polymorphism of feldspars above 10 GPa

Nature Communications, 2020
Feldspars are stable at pressures up to 3 GPa along the mantle geotherm, but they can persist metastably at higher pressures at colder conditions. Here, above 10 GPa the authors find  new high-pressure polymorphs of feldspars that could persist at depths
Anna Pakhomova, Dariia Simonova, Iuliia Koemets, Egor Koemets, Georgios Aprilis, Maxim Bykov, Liudmila Gorelova, Timofey Fedotenko, Vitali Prakapenka, Leonid Dubrovinsky   +9 more
doaj   +1 more source

Trace elements in some Finnish pegmatitic potassium feldspars [PDF]

Bulletin of the Geological Society of Finland, 1968
Thirty eight potassium feldspar samples from pegmatites were analyzed for K, Na, Ca, Fe, Rb, Sr, Cs, Ba and Pb. The X-ray fluorescence method used and the distribution of the trace elements are described and discussed.
R. Lappalainen, K.J. Neuvonen
doaj   +1 more source

Ba, Sr, and Rb feldspar/melt partitioning in recent eruptions from Teide-Pico Viejo volcanic complex, Tenerife: New insights into pre-eruptive processes

Frontiers in Earth Science, 2023
The behaviour of Group I and II elements during the petrogenesis of felsic igneous rocks is largely controlled by feldspar-liquid relationships. Numerous experimental studies have addressed plagioclase/melt element partitioning, with fewer studies ...
Olaya Dorado, Olaya Dorado, John A. Wolff, Frank C. Ramos, Joan Martí   +4 more
doaj   +1 more source

K-feldspar enrichment in the Pacific pelagic sediments before Miocene

Progress in Earth and Planetary Science, 2023
The mineralogy of atmospheric silicate dust controls its interaction with clouds. K-feldspar has a remarkably high ice-nucleating activity, and its distribution may have influenced the global climate throughout Earth's history.
Yoichi Usui, Toshitsugu Yamazaki
doaj   +1 more source

First-Principles Study of the Structural Evolution of Microcline Under High Pressure

Crystals
Microcline is an important rock-forming mineral in the Earth’s crust, and characterizing its structural behavior under compression is essential for understanding the high-pressure response of feldspar minerals under geological conditions.
Baoyun Wang, Meisu Xiang
doaj   +1 more source

Possible reasons for anomalous fading in alkali feldspars used for luminescence dating of Quaternary deposits [PDF]

Estonian Journal of Earth Sciences, 2007
According to many publications, alkali feldspars are characterized by specific athermal (anomalous) fading of their thermoluminescence and optically-stimulated luminescence.
Jaek, Ivar, Molodkov, Anatoli, Vasilchenko, Valery   +2 more
doaj  

Potassium Fractionation and Stock in Clay Soils: Influence of Geochemical and Mineralogical Properties in Yogyakarta Region, Indonesia

Caraka Tani: Journal of Sustainable Agriculture
Research on potassium (K) dynamics in upland clay soils, particularly those derived from tertiary-aged rocks, remains limited in Yogyakarta. This study aimed to investigate the relationships among geochemical indices, K fractions, and K stock in upland ...
Eko Hanudin, Padana Aperta Barus, Makruf Nurudin, Sri Nuryani Hidayah Utami   +3 more
doaj   +1 more source

Feldspar: Application and Implementation [PDF]

, 2012
The Feldspar project aims to develop a domain specific language for Digital Signal Processing algorithm design. From functional descriptions, imperative code (currently C) is generated. The project partners are Ericsson, Chalmers and ELTE, Budapest. The background and motivation for the project have been documented elsewhere [3].
Emil Axelsson, Mary Sheeran
openaire   +1 more source

Feldspar alteration by disequilibrium CO₂-H₂O fluids in reservoir sandstones: implications for CCS [PDF]

Solid Earth
Understanding how the minerals in reservoir rocks respond to CO2 injection is vital for the success and safety of Carbon Capture and Storage (CCS) projects. Feldspars are the most common mineral in the Earth's crust and act as primary framework grains in
N. J. C. Farrell, L. Yang, M. J. Flowerdew, C. Mark, C. Mark, B. Ardo, K. G. Taylor, N. Bigaroni, M. Pointon, L. Hughes, J. Waters, L. Paul   +11 more
doaj   +1 more source

The damage and failure mechanism of prestatically loaded rock during medium‐strain rate cyclic impact loading

Deep Underground Science and Engineering, EarlyView.
Based on experimental results and theoretical analysis, an established rock damage accumulation model that comprehensively considers the preapplied static load, impact peak value, impact frequency, and impact times. Abstract To study the rock damage mechanism under high static loading and superimposed medium strain rate cyclic impact loading, a series ...
Wei Wang, Hanpeng Wang, Zicheng Wang, Xinyuan Xie, Yunhao Wu, Jinhou Zhang, Dekang Sun   +6 more
wiley   +1 more source