Results 91 to 100 of about 1,213,951 (200)

Magnetic susceptibility of Variscan granite-types of the Spanish Central System and the redox state of magma

Geologica Acta, 2017
Magnetic susceptibility (MS) has been measured in Variscan granites from central Spain. They yield values in the order of 15 to 180μSI units for S- and I-type granites, indicating that both types belong to the ilmenite series.
C. VILLASECA, V.C. RUIZ-MARTÍNEZ, C. PÉREZ-SOBA   +2 more
doaj  

Geochemical indicators for cobalt-rich skarn exploration: constraints from the Pusangguo granodiorite (Gangdese) on geochemistry, zircon U-Pb geochronology and Hf-Nd-Sr isotopes

Frontiers in Earth Science
The Pusangguo skarn-type copper-polymetallic deposit in the Gangdese metallogenic belt hosts economic cobalt mineralization. An integrated study of petrography, zircon U-Pb geochronology, whole-rock geochemistry, and Sr–Nd–Hf isotopes indicates the ore ...
Zhaxi Pubu, Qiong Ci, Fuzhi Gong, Nan Chao   +3 more
doaj   +1 more source

Controlling factors of the metallogenic intensity in Han–Xing-type skarn iron deposits: insights from trace elements in magmatic magnetite

Frontiers in Earth Science
The Handan–Xingtai region is one of the important production areas of skarn-type iron deposits in China. The magmatic rocks associated with iron mineralization in this region are predominantly intermediate-basic and intermediate-felsic in composition ...
Jin Yanan, Jin Yanan, Wang Denghong, Zhang Juquan, Zhang Juquan, Zhang Long   +5 more
doaj   +1 more source

Pressure Dependence of the Oxygen Electrode

, 2020
A commercial oxygen electrode (YSI 5750) has been calibrated from 1 to 1500 bar. The theory of the pressure dependence of the electrode processes, the oxygen fugacity, and the membrane permeability is presented.
Jan E ~lmheim, Eddie Morild
core  

Volatiles and Redox Along the East African Rift

Geochemistry, Geophysics, Geosystems
The upper mantle under the Afar Depression in the East African Rift displays some of the slowest seismic wave speeds observed globally. Despite the extreme nature of the geophysical anomaly, lavas that erupted along the East African Rift record modest ...
Maryjo Brounce, Sara Scoggins, Tobias P. Fischer, Heather Ford, Joseph Byrnes   +4 more
doaj   +1 more source

Geological characteristics of neoproterozoic motianling granitic pluton hosting uranium mineralization in North Guangxi, China: Insights from biotite chemistry

Frontiers in Earth Science
The Motianling pluton represents a characteristic U-bearing granite pluton in South China. Biotite serves as an indicator for the mineralization of metals such as Cu, Sn, and W in granite. Previous studies have extensively investigated the U metallogenic
Pailong Luo, Pailong Luo, Chunying Guo, Chunying Guo, Chunying Guo, Qiaohui Pi, Qiaohui Pi, Ning Wang, Ning Wang, Naiyuan Liu, Naiyuan Liu, Naiyuan Liu   +11 more
doaj   +1 more source

Evidence for a dominantly reducing Archaean ambient mantle from two redox proxies, and low oxygen fugacity of deeply subducted oceanic crust. [PDF]

Sci Rep, 2019
Aulbach S, Woodland AB, Stern RA, Vasilyev P, Heaman LM, Viljoen KS.   +5 more
europepmc   +1 more source

Redox variations in Mauna Kea lavas, the oxygen fugacity of the Hawaiian plume, and the role of volcanic gases in Earth's oxygenation. [PDF]

Proc Natl Acad Sci U S A, 2017
Brounce M, Stolper E, Eiler J.
europepmc   +1 more source

Effect of Oxygen Fugacity on Fassaitic Pyroxene

Effect of Oxygen Fugacity on Fassaitic Pyroxene
Stability of fassaitic pyroxene in the system CaMgSi2O6-CaFeAlSiO6-CaAl2SiO6-CaTiAl2O6 is discussed on the basis of published data. In the system CaMgSi2O6-CaFeAlSiO6 the stability field of clinopyroxene decreases with an increase in CaFeAlSiO6 content and a decrease in oxygen fugacity at constant temperature.
openaire   +1 more source

Sensibility of tourmaline chemistry to granitic magma composition and oxygen fugacity

Massive granitic magmatism is a dominant feature of the Central Iberian Zone (CIZ) of the Variscan Orogen. For the most part, these are S-type per-aluminous granitic rocks exhibiting variable degrees of evolution and compositions ranging from ...
Ribeiro da Costa, Isabel, Antunes, Isabel Margarida Horta Ribeiro   +1 more
core   +1 more source