Earths Richat Structure
Explanation:
What on Earth is that?
The
Richat Structure
in the
Sahara Desert of Mauritania
is easily visible from space
because it is nearly 50 kilometers across.
Once thought to be an
impact crater, the
Richat Structure's
flat middle and lack of shock-altered rock indicates otherwise.
The possibility that the
Richat Structure
was formed by a
volcanic eruption
also seems improbable because of the lack of a dome of
igneous or volcanic rock.
Rather, the layered
sedimentary rock
of the Richat structure is now thought by many to have
been caused by uplifted rock sculpted by
erosion.
The
above image was captured by the
ASTER instruments
onboard the orbiting orbiting
Terra satellite.
Why the
Richat Structure is nearly circular remains a mystery.
Authors & editors:
Robert Nemiroff
(MTU) &
Jerry Bonnell
(USRA)
NASA Web Site Statements, Warnings,
and Disclaimers
NASA Official: Jay Norris.
Specific
rights apply.
A service of:
LHEA at
NASA /
GSFC
& Michigan Tech. U.