Elgygytgyn is a crater lake in Chukotka. Located on the Anadyr plateau, in the Anadyr region, about 390 kilometers north-west of Anadyr. The name is translated from Chukchi as "white lake".
The diameter of the
lake is about 12 kilometers;
depth in the central part of 169 m;
maximum depth - 174 m;
area - 119 km²;
volume - 14.1 km³;
catchment area - 293 km²;
the average temperature is about 3 ° C
in the bottom layers and about 0 ° C at the surface;
height above
sea level - 489 m.
For most of the year, the surface of the lake
is covered with ice; in some years it does not have time to melt
even in summer. The shores of the lake are bound by permafrost, its
thickness is 481 m. About 50 tributaries flow into the lake. In the
mouths of rivers and streams, the lake water in summer can warm up
to +7 +10 ° C. The Enmyvaam River flows out of the lake (a tributary
of the Belaya River, Anadyr basin).
There are no permanent
settlements of people near the lake, there are no roads to it.
The bottom sediments of the lake have a depth of more than 200 m
and are a repository of information about the conditions of the
natural environment of this region over the past three and a half
million years.
Three types of char (palii) live in water layers of Lake Elgygytgyn of different depths: large and predatory Boganid char (below), as well as planktivorous smallmouth char, and long-feather char (above). Svetovidov's long-finned char (Salvethymus svetovidovi) is a narrow-range fish species, described in 1990, not found anywhere outside this lake. In order to protect it, the lake was declared a natural monument of Chukotka.
The lake is a water-filled depression in
the earth's surface that was formed about 3.6 million years ago.
The basin of the lake is of meteorite origin and is an impact
crater (astroblem) filled with water and sediments. For a long time,
there was an assumption that this is a volcanic crater, but it was
refuted by the results of drilling the bottom of the lake in 2008.
The crater is located in acid rocks of volcanic origin (including
tuffs) and at the time of research was the only impact crater known
on Earth in rocks of this type.
The first lake
was described by Sergei Vladimirovich Obruchev in the 1930s. In his
works, this lake was called Elgydhyn.
In the 1950s, research
was carried out by employees of the Anadyr permafrost station. The
depths were measured, the temperature was measured, water samples
were taken, the lake shoreline was surveyed, rock samples were taken
from wells and outcrops, samples of lake bottom sediments, plankton
samples, control samples of lake water.
In 1984, an
expedition to the lake was undertaken by the Magadan writer Albert
Miftakhutdinov, dedicating it to the 50th anniversary of Oleg
Kuvaev.
In the 1980s-1990s, specialists from the
North-Eastern Complex Research Institute (Magadan) worked on the
lake. Many articles and books have been published on the results of
the expeditions.
In 1998, 2000, 2003, 2008 and 2009,
international expeditions went to the lake: researchers from the
Institute of Geology and Geophysics of the University of Leipzig,
the Institute for Polar and Marine Research named after I. Alfred
Wegener (Germany), Massachusetts and Alaska Universities (USA),
Russian scientists from the Arctic and Antarctic Research Institute
of Roshydromet (St. Petersburg) and the North-Eastern Complex
Research Institute of the Far Eastern Branch of the Russian Academy
of Sciences. The international project "Paleoclimate of Lake
Elgygytgyn" is funded by the USA and Germany.
In August 2020,
employees of the Kronotsky Nature Reserve, Moscow State University
named after I. MV Lomonosov, Institute of Ecology and Evolution. A.
N. Severtsov RAS and Institute of Developmental Biology named after
NK Koltsov RAS, within the framework of a scientific expedition,
conducted research on the ichthyofauna of Lake Elgygytgyn.
Scientists also collected hydrobiological materials - samples of
invertebrates that inhabit the bottom of the lake and the water
column. Instrumental complex measurements of the parameters of the
fish habitat have been carried out. Further processing of field
materials will reveal many mysteries of the unique lake and its
surroundings.
In the winter of 2008-2009. An international group of scientists
from Russia, Germany and the United States drilled the bottom of
Lake Elgygytgyn with equipment installed on the ice and studied the
bottom sediments of the lake and the rocks beneath them.
A
well drilled under a 225-meter layer of lacustrine deposits revealed
a layer of shock breccia - suevite, more than 200 meters thick.
Rocks of this type are formed only in impact craters - thus, the
meteoric origin of the lake has been confirmed.