imaggeo on mondays

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

Samuele Papeschi January 17, 2022

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

Thomas P. Ferrand January 10, 2022

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

Bernardo Cesare January 3, 2022

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]

Imaggeo On Monday: A meander in the meltwater valley

Julien Seguinot December 27, 2021

A meander in the meltwater valley . Credit: Julien Seguinot (distributed via imaggeo.egu.eu)

At the edge of the Greenland Ice Sheet, surface melt releases old layers of dust, that have travelled thousands of years into the ice. Under sunny weather, the dust heats up with radiation, melts the ice underneath, and thus accumulates in tiny potholes and meltwater creeks. However, this photo was taken after a rainy day. The rain triggered increased melt on the surface of the ice irrelevant of i ...[Read More]