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Earth of fire

Actualité volcanique, Article de fond sur étude de volcan, tectonique, récits et photos de voyage

Publié par Bernard Duyck
Publié dans : #Excursions et voyages

Located as the Kurile Lake in the Pauzhetka caldera, dated 443,000 years , the complex of domes Diky Greben covers more than 60 km ².

The complex consists of Mont Nepriyatnaya - "Unpleasant " , the main dome , many flanks domes , their lavas and pyroclastic flows ; it is the largest extrusive block of the Kamchatka - Kurile arc .

 

The Diky Greben complex , Mt Nepriyatnaya , its N & S flows, and , in the background , the Kuril Lake - / KSCNET Photo Nikolai Smelov

The Diky Greben complex , Mt Nepriyatnaya , its N & S flows, and , in the background , the Kuril Lake - / KSCNET Photo Nikolai Smelov

The complex is formed during three short periods of activity separated by long rest periods of about 3,000 years each.

- His life begins to 5700-5600 BC, after the collapse of the caldera of Lake Kuril .

- The second phase takes place between 3500 and 2250 BC.

- The greater part of the complex, including lava north and south of Mt Nepriyatnaya , was formed during an eruption in the year 350 : on the north of the latter, a thick lava flow lined with well expressed levees, and south, a topography that marks its origins in a sector collapse of the main lava dome. A total of 9-10 km ³ of dacite and 2-3 km ³ of andesite was issued at that time.

Two large craters and some smaller vents were formed thereafter.

During these three phases , deformation and landslides occurred , some constituting dams on the Ozernaia River, the drainage of Lake Kuril .

Diky Greben - Mt Nepriyatnaya and his flows - Landsat 7 image of Dikii Greben ' volcano draped over a digital elevation model . Processed by Dmitry Melnikov .

Diky Greben - Mt Nepriyatnaya and his flows - Landsat 7 image of Dikii Greben ' volcano draped over a digital elevation model . Processed by Dmitry Melnikov .

The Kambalny , located south of the volcano -tectonic depression Pauzhetka is the major stratovolcano the southernmost of the peninsula of Kamchatka .

Peaking at 2156 meters, it consists of two cones : in the west, a cone formed there about 6,300 years , was destroyed by a large collapse 6,000 years ago ( radiocarbon ), which has generated at least three avalanches debris , estimated between 5 and 10 km ³ of total volume.

 

The Kambalny - photo Igor Shpilenok / live newspaper

The Kambalny - photo Igor Shpilenok / live newspaper

The first avalanche traveled 14 km south-easterly direction . A new cone is then formed in the crater , following strong explosive eruptions . Another collapse involved as the former cone cone as the new emerging cone, forming a deposit of 20 km long and 5 wide, to the SSO of the volcano. The third debris avalanche , which traveled more than 10 km NE, is dominated by hydrothermally altered rocks of the former ridge.

Subsequent eruptions have built the new cone, that filled a part of the collapsed crater, forming an asymmetric structure. The present crater is 800 meters wide by 400, and 150 m deep . Five cinder cones dot the flanks of the volcano .

The clearance between the hummocks of the debris avalanches deposits is now occupied by peatlands , which protected all the thin layers of ash from the volcanoes of South-Kamchatka and history.

The last major eruption of Kambalny date of 1350 ; the phreatic eruption left debris on the southwest slopes of the volcano . Subsequent smaller eruptions have produced lahars .


 

Kambalny - area avalanche hummock swamp - photo LD Shulerzhitsky

Kambalny - area avalanche hummock swamp - photo LD Shulerzhitsky

Its current activity is confirmed by the presence of zones of fumaroles , hot springs and mud pots in nine areas concentrated on the dorsal Kambalny dominant the tundra of 800-1000 meters.
 

Hydrothermal field near Black Cliffs / Kambalny volcano - photo I.Shpilenok / Kronoki.ru

Hydrothermal field near Black Cliffs / Kambalny volcano - photo I.Shpilenok / Kronoki.ru

Hydrothermal field near Black Cliffs / Kambalny volcano - photo I.Shpilenok / Kronoki.ru

Hydrothermal field near Black Cliffs / Kambalny volcano - photo I.Shpilenok / Kronoki.ru

Sources :

- KSCNET - Holocene Kamchaka volcanoes - link

- Global Volcanism Program - Diky Greben

- Gloval Volcanism Program - Kambalny

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