Page 21 - Amazonia

Amazonia | 21
Magazine Name 21

Scientists estimate the subterranean river may their results last week at the
be 6,000km long and hundreds of times wider International Congress of the
Society Brasiliera Geophysical
than the Amazon. Covering more than 7 million square in Rio de Janeiro.

kilometres in South America, the Amazon basin is one The researchers used a math-
of the biggest and most impressive river systems in the ematical model to predict the
presence of the underground
world. river, based on the measured
changes in temperature down
the wells. In the presentation,
Piementel said that the flow of
groundwater was almost verti-
cal through the rocks to depths
of around 2,000m. After this,
the water flow changes direc-
tion and becomes almost hori-
zontal.
According to the researchers,
the presence of the Rio Hamza
river might account for the
relatively low salinity of the wa-
ters around the mouth of the
Amazon.
Professor Hamza said Piemen-
tel’s measurements represented
preliminary work on the discov-
ery of the new river, but Hamza
said he expected to confirm the
existence of the flow with addi-
tional measurements within the
Both the Amazon and Hamza water flow through the Ama- next few years.
flow from west to east and zon per second at speeds of
are around the same length, up to 5 metres per second. The Using mathematical models re-
at 6,000km. But whereas the underground river’s flow rate lating temperature differences
Amazon ranges from 1km to has been estimated at around to water movement, the scien-
100km in width, the Hamza 3,900m3 per second and it tists inferred that water must
ranges from 200km to 400km. barely inches along at less than be moving downwards through
a millimetre per hour. the ground around the holes,
The underground river starts and then flowing horizontally
in the Acre region under the The Hamza was located using at a depth of several km. They
Andes and flows through the data collected inside a series of concluded that this movement
Solimões, Amazonas and 241 abandoned deep wells that had to be from West to East,
Marajó basins before opening were drilled in the Amazon re- mimicking the mighty Amazon
out directly into the depths of gion by the petrochemical com- itself.
the Atlantic Ocean. pany Petrobras in the 1970s
and 1980s. Elizabeth Tavares A true underground river on
The Amazon flows much fast- Pimentel and Valiya Hamza of this scale - 6,000km (4,000
er than the Hamza, however, the Department of Geophysics miles) long - would be the long-
draining a greater volume of at Brazil’s National Observato- est of its kind in the world by
water. Around 133,000m3 of ry led the work and presented far.

https://www.bbc.com/news/science-environment-14693637