GeoLog

Geochemistry, Mineralogy, Petrology & Volcanology

Imaggeo On Monday: Quartz – sericite mylonite, Calamita, Elba

January 17, 2022
Imaggeo On Monday: Quartz – sericite mylonite, Calamita, Elba
Quartz - sericite mylonite, Calamita, Elba . Credit: Samuele Papeschi (distributed via imaggeo.egu.eu)

Concomitant thrusting and magmatism resulted in the development of ductile mylonites in the Calamita Schists, part of the contact aureole of the Late Miocene Porto Azzurro pluton. This mylonite is made up of stretched and recrystallized quartz layers, interlayered with thin sericite-rich levels. Sericite resulted from the crushing of contact-metamorphic minerals such as andalusite, cordierite, and ...[Read More]

Imaggeo On Monday: Artificial peridotite takes its gold coat off

January 10, 2022
Imaggeo On Monday: Artificial peridotite takes its gold coat off
Artificial peridotite takes its gold coat off . Credit: Thomas P. Ferrand (distributed via imaggeo.egu.eu)

Sometimes in order to test a theory about how processes work below the surface of the Earth, scientists need to recreate minerals found in very specific circumstances. This photograph was taken through a binocular microscope during a critical step of the creation of artificial peridotite: extraction of the artificial peridotite from its gold capsule. The sample is a little cylinder, 3 mm long with ...[Read More]

Imaggeo On Monday: Geometric Microscape of Agate

January 3, 2022
Imaggeo On Monday: Geometric Microscape of Agate
Geometric Microscape of Agate . Credit: Bernardo Cesare (distributed via imaggeo.egu.eu)

“Crazy Lace” is an agate collected in Mexico, which offers great opportunities for aesthetic photomicrography. Here we see the common arrangement of fibers of chalcedony (microcrystalline quartz) in parallel bands alternating with black thin layers of Fe oxides. Polarized light photomicrograph, crossed polarizers and red tint plate. width 5.4 mm. Sample kindly provided by Denise M. Har ...[Read More]

Winners of the EGU Best Blog Posts of 2020 Competition

February 5, 2021
Winners of the EGU Best Blog Posts of 2020 Competition

2020 was a brilliant year for our blogging network here at EGU. Across the EGU’s official blog, GeoLog, as well as the network and division blogs there were so many interesting, educational and just downright entertaining posts this year it was hard to get the blog editors to choose their favourites! Nevertheless at the beginning of January, to celebrate the excellent display of science writing ac ...[Read More]