Rewilding in Africa brings back key species to restore ecological balance

Episode Transcript

Speaker 1 (00:00):
Earth's crust is dripping into the interior. Researchers have found
evidence of lithospheric dripping occurring beneath the Central Anatolian Plateau
in Turkey. Beneath the Conya Basin, a depression located on
the Central Anatolian Plateau, Earth's crust is slowly dripping deeper
into the planet. This process, known as lithospheric dripping, is

(00:24):
gradually reshaping the surface geology of both the basin and
the surrounding plateau. The phenomenon was only recently identified on Earth,
and geologists are still exploring its various expressions. Analyzing satellite data,
we observed a circular feature in the Conya Basin where

(00:46):
the crust appears to be sinking or the basin deepening,
said Julia Anderson, a geophysicist at the University of Toronto.
This led us to examine data beneath the surface, where
we found so issmic anomalies in the upper mantle and
a thickened crust, indicating high density material and revealing the

(01:07):
process of lithospheric dripping. As the lower part of Earth's
crust heats up to a certain temperature, it becomes sticky
and begins to drip downward, similar to honey or syrup,
but on a much larger and slower scale. When a
drop forms and descends, it pulls the crust downward, creating

(01:28):
depressions or basins. As the drop sinks into the mantle,
the surface rebounds and bulges with a spreading effect. Researchers
have only recently started to understand this process through modeling
its evolution. Anderson and her team identified an area of
the mantle where lithospheric dripping is happening beneath the Arizaro

(01:52):
Basin in the central Andes Now. After careful surface geological
analysis and experimentation, they have discovered another instance of lithospheric
dripping beneath the central Anatolian Plateau, which has been slowly
rising over time. Previous research suggested that this region has

(02:13):
gained around one kilometer in elevation over ten million years
due to crustal dripping. The Conya Basin is sinking at
a rate of about twenty millimeters per year, which may
not seem significant, but the subsidence in a rising plateau
warrants further investigation. The research team found that the broader

(02:34):
plateau region is in the rebound phase of lithospheric dripping,
after molten rock from the crust sank into the mantle
while the Conya basin is forming a second, smaller drip.
They validated their model through laboratory experiments. In these the
research has used a high viscosity silicone polymer called polydemethyl

(02:57):
sylock sane to mimic Earth's stick key lower mantle, while
a mix of polydemethyl siloxane and clay simulated the upper mantle.
Ceramic beads and quartz sand acted as the crust. By
pressing a seed like object into the upper mantle layer,
they recreated the dripping process and observed the results. Within

(03:20):
ten hours, the first drip began to form and descend.
After fifty hours the second drip started. Neither drip was
associated with horizontal surface deformation, only vertical changes, which matched
the Conya basin. The results suggest lithospheric dripping is a
multi stage process, explaining the simultaneous uplift and subsidence in

(03:46):
the Central Anatolian Plateau. The team published their findings in
the journal Nature Communications.