GeoLog

Half Dome

Imaggeo on Mondays: Sunset and moonrise at Yosemite

Imaggeo on Mondays: Sunset and moonrise at Yosemite

This side view of Half Dome at Yosemite National Park (California, USA) was taken from Washburn Point, a less frequented overlook a few hundred meters away from the popular Glacier Point outlook. The sun just on the right side behind the camera, which gave the orange tint to the back side of Half Dome. At the same time a full moon was mere minutes from bursting in the background, which resulted in the warm glow of the horizon. A few stars have already started appearing on the clear sky and a few star trails are visible.

Description by Teamrat Ghezzehei, as it first appeared on imaggeo.egu.eu.

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.

Imaggeo on Mondays: Half dome at sunset

Imaggeo on Mondays: Half dome at sunset

Yosemite’s Half Dome stands, majestic, over a granite dominated terrain in the Yosemite Valley area;  one of the most beautiful landscapes in northern America, and arguably, the world – it is also an Earth scientist’ playground.

Stamped into the west slope of the Sierra Nevada range, the Yosemite Valley is a collection of lush forests, deep valleys, meandering rivers and streams, all punctuated by huge domes and cliffs of ancient volcanic origin.

Come and explore this part of the world and you’ll not miss Half Dome. Standing at the head of the valley, the quartz monzonite (a coarse grained orthoclase and plagioclase feldspar dominated rock) structure rises a little short of 2700 m above sea level.

Despite standing proud in the present landscape, it was once a magma chamber, buried deep below a volcano. Over a long period of time, the molten magma cooled and crystalised to form the coarse granite rock we see today. Erosion and exposure did the rest, eventually exhuming the dome and cutting deep valleys into the surrounding landscapes.

For more information on the geology of the Yosemite Valley and Half Dome, please refer to these United States Geological Survey (USGS) resources:

The Geological Story of Yosemite Valley
How did Half Dome, acquire its unique shape?
Bedrock Geology of the Yosemite Valley Area

Imaggeo is the EGU’s online open access geosciences image repository. All geoscientists (and others) can submit their photographs and videos to this repository and, since it is open access, these images can be used for free by scientists for their presentations or publications, by educators and the general public, and some images can even be used freely for commercial purposes. Photographers also retain full rights of use, as Imaggeo images are licensed and distributed by the EGU under a Creative Commons licence. Submit your photos at http://imaggeo.egu.eu/upload/.