Image: Earth from space -- wind-inspired design

Nov 19, 2010
Image: ESA

The pastel colours and soft, flowing shapes in this Envisat radar image of the Tanezrouft Basin in the Algerian Sahara contradict the harshness of the terrain that has led to it being commonly referred to as the 'Land of Terror'.

Stone and pebbles make up most of the Sahara surface in Northern Africa. Erosion – first by water, now by wind – has created this landscape of hills, basins, steep canyon walls, stone plateaus and multi-storey sand dunes.

The concentric loop patterns of the sedimentary rock are exposed by wind erosion, much like the grain of wood after sanding.

Radar images reveal surface roughness – the rougher the surface, the brighter it appears. Hence, darker areas represent softer rock with a sandy or small-stoned surface.

Many steep canyon walls rising 250–500 m tower above the surrounding arid terrain. In this image, very low cliffs and faults appear bright.

This image was created by combining three Envisat radar passes (23 March 2009, 1 June 2009 and 14 September 2009) over the same area. The colours result from changes in the between acquisitions.

Explore further: Heavy metal frost? A new look at a Venusian mystery

add to favorites email to friend print save as pdf

Related Stories

Envisat monitors oil spill proximity to Loop Current

May 05, 2010

As fears grow that the Loop Current in the Gulf of Mexico could soon catch the oil slick and drag it south towards coral reefs in the Florida Keys, scientists are monitoring the situation closely with ESA's ...

Gulf of Mexico oil spill in the Loop Current

May 19, 2010

(PhysOrg.com) -- Scientists monitoring the US oil spill with ESA's Envisat radar satellite say that it has entered the Loop Current, a powerful conveyor belt that flows clockwise around the Gulf of Mexico ...

Insight into volcanic eruptions, courtesy of space

Oct 15, 2010

(PhysOrg.com) -- Scientists are crediting satellite imagery with helping to predict where volcanic eruptions could strike. It is well known that earthquakes can stress Earth’s crust and trigger subsequent ...

Martian rock arrangement not alien handiwork

Jan 07, 2009

At first, figuring out how pebble-sized rocks organize themselves in evenly-spaced patterns in sand seemed simple and even intuitive. But once Andrew Leier, an assistant geoscience professor at the U of C, started observing, ...

Recommended for you

Heavy metal frost? A new look at a Venusian mystery

5 hours ago

Venus is hiding something beneath its brilliant shroud of clouds: a first order mystery about the planet that researchers may be a little closer to solving because of a new re-analysis of twenty-year-old ...

Hot explosions on the cool sun

10 hours ago

(Phys.org) —The Sun is more spirited than previously thought. Apart from the solar eruptions, huge bursts of particles and radiation from the outer atmosphere of our star, also the cooler layer right below ...

Europe secures new generation of weather satellites

11 hours ago

Contracts were signed today to build three pairs of MetOp Second Generation satellites, ensuring the continuity of essential information for global weather forecasting and climate monitoring for decades to ...

User comments : 0