GeoLog

imaggeo on mondays

Imaggeo On Monday: A steady silent witness

Imaggeo On Monday: A steady silent witness

I took this picture during a sunny field work day in the Mara Wetland, Tanzania. The granitic inselberg appeared to me as a huge silent witness not only of siltation and inundation of the wetland but also of the human actions. Slash-and-burn is widely used to deforest lands and riparian vegetation for new crops and grazing fields along the Mara River. The induced habitat degradation is jeopardizin ...[Read More]

Imaggeo On Monday: Stands of Time

Imaggeo On Monday: Stands of Time

Within the heart of the Malagasy Hauts-Plateaux, the rolling grasslands are pitted by deep incisions locally referred to as lavaka (‘hole’ in Malagasy). These mass failure features provide vast quantities of terrestrial matter to local freshwater arteries, accounting for over 80% of the annual sediment load of the Betsiboka River. The collapse of the overlying laterite exposes a comparatively nutr ...[Read More]

Imaggeo On Monday: The Heart of a Stone

Imaggeo On Monday: The Heart of a Stone

Heart-shaped glomerocryst (aggregate of phenocrysts) made of plagioclase and pyroxene in a cordierite-bearing dacitic lava from Lipari (Eolie Islands). I study the crustal xenoliths of these lavas to understand the processes accompanying high-temperature metamorphism and crustal melting. But I came across this spectacular glomerocryst and couldn’t help but take a picture! Polarized light pho ...[Read More]

Imaggeo On Monday: Salt marsh in El Rocío (Huelva, SW Spain)

Imaggeo On Monday: Salt marsh in El Rocío (Huelva, SW Spain)

The coast line of Huelva is furrowed by wetlands and sprinkled with salt flats. These areas are a sanctuary for wildlife and are visited by migrating birds travelling between Europe and Africa. In these wetlands grow the salt cedar, the Phoenician juniper, the mastic tree, the Montpellier cistus, the rockrose, the kermes oak, rosemary, cordgrass, reeds and bulrushes. The picture shows part of the ...[Read More]