Volcanic eruption on the Kuril Islands. Underwater volcanic group "Paramushirskaya

Volcanoes of the Kuril Islands

Volcanic activity is observed exclusively in the Greater Kuril Range, whose islands are mainly of volcanic origin and only the northernmost and southernmost are composed of Neogene sedimentary rocks. These rocks serve here as the foundation on which volcanic structures arose.

Volcanoes of the Kuril Islands are confined to deep faults in the earth's crust, which are a continuation of faults in Kamchatka. Together with the latter, they form one volcanic and tectonic Kuril-Kamchatka arc, convex to the side Pacific Ocean. On the Kuril Islands There are 25 active volcanoes (of which 4 are underwater), 13 are attenuated and more than 60 are extinct. The volcanoes of the Kuril Islands have been studied very little. Of these, the Alaid, Sarychev Fuss, Snow and Milya volcanoes stand out for their increased activity. Volcano Alaid is located on the first northern island (Atlasov Island) and is the most active of all the Kuril volcanoes. It is the highest (2239 m) and beautifully rises in the form of a regular cone directly from the surface of the sea. At the top of the cone in a small depression is the central crater of the volcano. By the nature of the eruptions, the Alaid volcano belongs to the ethno-Vesuvian type. Over the past 180 years, eight eruptions of this volcano and two eruptions from the lateral cone of Taketomi, which formed at the time, are known. eruptions of Alaid in 1934. Volcanic activity on the Kuril Islands is accompanied by numerous hot springs with temperatures from 36 to 100 C. The springs are diverse in form and salt composition and are even less studied than volcanoes.

Underwater volcanic group "Paramushirskaya"

Within this volcanic group, the underwater volcano Grigorieva, an underwater volcano located to the west of about. Paramushir and underwater lava cones at about. Paramushir.

Underwater volcano Grigorieva. The flat-topped underwater volcano Grigoriev, named after an outstanding Russian geologist, is located 5.5 km northwest of about. Atlasov (Alaid volcano) (Fig. 17).

It rises from depths of 800-850 m, and its base has grown together with the base of the Alaid volcano. Grigoriev volcano is located on the general line of the north-north-western direction of the location of the side cones of the Alaid volcano.

The dimensions of the base of the volcano along the isobath 500 m 11.5 8.5 km, and the volume of the building is about 40 km 3 . The steepness of the slopes reaches 10o-15o.

The top of the underwater volcano Grigorieva was cut off by abrasion and leveled to a level of 120-140 m (Fig. 18), which practically corresponds to the sea level in the Late Pleistocene. In the southern part of the peak, rocky ledges were noted, rising to a depth of 55 m. Apparently, these rocky ledges represent a prepared neck.

Judging by the records of continuous seismic profiling, the volcanic edifice is composed mainly of dense volcanic rocks.

An intense magnetic field anomaly with a amplitude of more than 1000 nT is confined to the underwater volcano Grigoriev (see Fig. 18). All rock ledges, marked in the southern part of the flat top, are clearly fixed in the magnetic field by the presence of local anomalies. The volcanic edifice is magnetized in the direction of the current magnetic field.

During the dredging of an underwater volcano, basalts were raised, varying in composition from very low-silica to high-silica varieties. The remanent magnetization of these basalts varies in the range of 7.3-28.5 A/m, and the Koenigsberger ratio - in the range of 8.4-26.5.

Data from echo sounding, continuous seismic profiling, hydromagnetic surveys, and measurements of the magnetic properties of dredged samples suggest that the entire edifice of the underwater volcano Grigoriev is composed of dense basalts.

The presence of a pre-Holocene 120-140 meter terrace and the magnetization of the volcanic edifice in the direction of the modern magnetic field allows us to estimate the age of the formation of the volcano in the range of 700-10 thousand years ago.

An underwater volcano to the west of about. Paramushir. In 1989, during the 34th and 35th cruises of the R/V Vulkanolog in the rear part of the Kuril arc, 80 km west of the island. Paramushir was discovered and studied in detail previously unknown underwater volcano.

This submarine volcano is located at the intersection of the Atlasov trough with the continuation of the transverse structure of the 4th Kuril trough. Like the Belyankin and Edelstein underwater volcanoes, it is located far in the rear of the Kuril Island Arc and is 280 km away from the axis of the Kuril-Kamchatka Trench.

The volcano is located on a gentle slope of a trough, rising 650–700 m above the surrounding bottom of the Sea of ​​Okhotsk (Fig. 19). Its base is slightly elongated in the northwest direction and measures ~ 6.5 7 km. The top of the mountain is complicated by a number of peaks. The negative shape of the relief encircles the base of the volcano in an almost closed ring.

In the vicinity of the volcano, there are no extended scattering horizons in the sedimentary section. Only at the very base, an unextended "acoustically muddy" wedge sometimes stands out, apparently due to the accumulation of detrital material and landslide sediments. The position in the section of this “acoustically muddy” wedge corresponds to the estimated time of the formation of the volcano, which, according to the NSP, is 400-700 thousand years.

Structural features of the sedimentary cover indicate that the magma breakthrough to the bottom surface here was not accompanied by a large-scale accumulation of volcanic-sedimentary material, and most likely ended with the formation of one or a series of volcanic extrusions. Most likely, the entire building is composed of volcanic rocks.

At a distance of 5-10 km from the volcano, according to the NSP data, three small (apparently magmatic) bodies were identified that did not reach the bottom surface. Overlying sediments are folded into anticlinal folds.

The anomalous field (T) a in the area of ​​the underwater volcano is characterized by positive values. Only in the northwestern part of the study area, negative field values ​​with an intensity of up to -200 nT are noted. The areas of positive and negative values ​​of the magnetic field are separated by a linear zone of high gradients, which strikes northwest. The horizontal field gradient in this zone reaches 80–100 nT/km. A positive anomaly of the magnetic field with an intensity of up to 400-500 nT is associated directly with the volcanic edifice. Near the summit part of the structure, a local maximum with an intensity of up to 700 nT was noted. The maximum of the anomaly is shifted to the south of the top of the volcano. Marked magmatic bodies that have not reached the bottom surface are not expressed as independent anomalies in the anomalous magnetic field.

The observed pattern of the anomalous magnetic field indicates the direct magnetization of the underwater volcanic structure.

Apparently, the age of the formation of the volcano is not older than 700 thousand years, which is in good agreement with the NSP data.

During the dredging of the near-top part of the mountain, mainly amphibole andesites were raised, with a subordinate amount of pyroxene andesite-basalts and plagiobasalts. In small quantities, there are fragments of granitoids, andesitic pumice, cinders, pebbles of sedimentary rocks, iron-manganese formations, and benthic biota.

Echo sounding, NSP, HMS and geological sampling data suggest that the bulk of the volcanic edifice is composed of rocks of andesite-basalt composition.

Underwater lava cones at about. Paramushir. On a number of cruises of the R/V Vulkanolog and on cruise 11-A of the R/V Akademik Mstislav Keldysh, a study was made of underwater gas-hydrothermal activity on the northwestern slope of the island. Paramushir. On cruise 11-A of the R/V Akademik Mstislav Keldysh, either 11 dives of the Pisis VII and Pisis XI, or 13 submersibles, were performed in the study area.

The signal for such a close study of this area was a radiogram sent on March 20, 1982 by the captain of the fishing vessel "Pogranichnik Zmeev" to the newspaper "Kamchatskaya Pravda" that near about. Paramushir "an active underwater volcano was discovered at a depth of 820 m, the extreme height of the ejection is 290 m ...". In April of the same year, on the 13th cruise of the R/V Vulkanolog, acoustic noise was detected at the indicated point, which is clearly manifested in the echo sounder records. Similar records were repeatedly recorded during research from the board of research vessels in the area of ​​active volcanoes and were associated with the action of underwater fumaroles. In its form, the identified interference resembled a torch. Subsequently, when conducting research at the indicated point, acoustic interference on the records of various echo sounders installed on board the R/V Vulkanolog was noted until 1991, when the last specialized cruise No. 40 of this vessel was performed within the RCD.

Prior to the start of research in the area of ​​the "torch" were not known any signs of manifestation volcanic activity. To establish the nature of the "torch" of anomalous water, so many studies were carried out. They made it possible to establish that the "torch" was formed by underwater gas-hydrothermal vents (SGHT), similar to an underwater fumarole, but not directly connected with any volcanic center. Therefore, the application of the term "underwater fumarole" to it would be incorrect.

PGTV is located on the west-north-western slope of about. Paramushir in the rear part of the KKOS, approximately in the middle between the Alaid and Antsiferov volcanoes. Its coordinates are 50o30.8 "N and 155o18.45" E. It is confined to a weakly manifested transverse volcanic zone, represented by almost completely buried extrusive domes or small volcanic cones, stretching from the Chikurachki volcano in a west-northwest direction. On the NSP records, these structures are similar to the side cinder cones of the Alaid volcano, which also have a transverse orientation with respect to the RCD. Most of the buried structures are 0.5-3 km in size at the base and 50-400 m in height. Taking into account that these dimensions are less than the inter-tack distance, excluding a small area around the PGTV itself, it can be assumed that the number of buried structures in the described area is somewhat larger. It should be noted that the buried structures in the KOD area during volcanological expeditions aboard the R/V Vulkanolog were found only in two places: in the PGTV area and near an underwater volcano to the west of the island. Paramushir.

Judging by the HMS data, not all volcanic buried structures have the same structure. Some of them are not expressed in any way in the magnetic field, but are only fixed on the NSP tapes, distinct positive or negative anomalies of the magnetic field are confined to others, and they are, most likely, lava domes or cones, frozen mainly in the sedimentary mass. Non-magnetic cone-shaped structures can be composed of cinder cones or acid rocks.

The largest lava cone is located at the northeastern end of the detailed study area. It is almost entirely located inside the sedimentary sequence, which here has a thickness of more than 1500 m. Only its near-top part rises above the bottom surface, forming a hill 100-120 m high. The recorded depth above the top is 580 m. The dimensions of this structure in its lower part at a depth of 800 -1000 m from the bottom surface reach 5-6 km. The size of the building according to the buried base is 7.5 11 km, the area is ~ 65 km 2, the total height is 1600 m. The steepness of the slopes of the building is 5o-8o. A smaller cone with a base size of ~3 km adjoins it from the south-southwest. Both of these structures are magnetic and form an anomaly, within which two extrema with an intensity of 370 and 440 nT are noted (Fig. 4). The buildings are magnetized in the direction of the modern magnetic field, and the age of their formation is not older than 700 thousand years.

The performed two-dimensional modeling showed that the effective magnetization of the northern cone is 1.56 A/m, and that of the southern cone is 3.7 A/m. Based on the average values ​​of effective magnetization for underwater volcanoes, it can be assumed that the northern cone is composed of andesites, and the southern cone is composed of andesite-basalts.

During PHA dives on the northern cone, plagioclase-hornblende andesites and predominantly homogeneous basalts were sampled.

Comparison of geomagnetic modeling results with geological sampling data suggests that the upper part of this cone is composed of basalts, while the deeper parts are composed of andesites.

Estimates of the age of the northern cone, given in various works, vary within the Neogene-Quaternary.

A small cone, located in the southern part of the detailed work area, has a base size of ~ 1.5 km in diameter. A negative anomaly of the magnetic field with an intensity of -200 nT is confined to it (see Fig. 4). The effective magnetization of this cone is 1.3 A/m, which corresponds to the magnetization of andesitic volcanoes. The negative nature of the magnetic field suggests that the age of formation of this cone is no younger than 700 thousand years.

It should be noted that the PGTV is located in a zone of increased fracturing with a large number of small faults.

PHA subsidence in the PGTV zone showed that the most characteristic landforms in the PGTV area are chaotically located sinkholes and pits. The size of the pits varies from 1 to 10 m in diameter and has a depth of up to 3 m. The distance between the pits is 0.5-2 m.

PGTV is associated with deposits of solid gas hydrates.

Employees of the IO RAS believe that the investigated outlets are gas, and not hydrothermal.

The studies performed have shown that the PGTWs are located within a weakly expressed Quaternary (Neogene-Quaternary?) volcanic zone. They are confined to a zone of increased fracturing and are not directly connected with any volcanic center. The nearest non-magnetic (slag?) cone is located ~ 2 km to the east-south-east of the point of manifestation of acoustic interference.

Underwater volcanic group "Makanrushi".

Within this volcanic group, the contrasting underwater volcanoes Belyankina and Smirnov, named after prominent Russian geologists, were studied. These underwater volcanoes are located in the rear of Onekotan Island (see Fig. 17). The underwater volcano Belyankina is located 23 km northwest of about. Makanrushi (Fig. 21). On navigation charts, prior to the work from the R/V Vulkanolog, two distinctive depths were shown in this area, which could be the depths marked above the peaks of this underwater volcano. Our studies unequivocally showed that the Belyankin underwater volcano has only one peak.

Belyankina volcano has the shape of an isometric cone and rises above the surrounding bottom to a height of about 1100 m. The sharp peak of the volcano is located at a depth of 508 m. Belyankina volcano is located not only outside the mountain structure of the Kuril-Kamchatka island arc, but even on the other side of the Kuril basin - on its northwestern slope. The maximum size of the base of the volcanic edifice is 97 km with an area of ​​about 50 km 2 . The volcano has steep slopes. Their steepness increases in the direction from the base to the top from 15o-20o to 25o-30o. The slopes of the volcano rising above the bottom of the basin are devoid of a sedimentary cover. The base of the overlying volcano is covered by a thick layer of sediments. On the seismograms of the NSP, they correspond to the pattern of the seismoacoustic image, which is generally typical for the sedimentary strata of this region of the Sea of ​​Okhotsk. The volume of the volcanic edifice, taking into account the part covered by sediments, is ~35 km3. The thickness of sedimentary deposits near the volcano exceeds 1000 m. With the available estimates of the rate of sedimentation in the Sea of ​​Okhotsk (20-200 m/m.y.), it would take from 1 to 10 m.y. to form this sequence.

Underwater volcano Belyankina clearly manifests itself in a magnetic field. It is associated with a magnetic field anomaly with a swing of 650 nT, the extremum of which is shifted to the southeast of the peak (see Fig. 21). The volcanic edifice has a direct magnetization.

During the dredging of the Belyankin underwater volcano homogeneous olivine basalts were raised. Based on the study of dredged rocks, some authors believe that the volcanic eruptions occurred in underwater conditions, while others - that in land conditions.

Measurement of the magnetic properties of the dredged samples showed that their residual magnetization varies within 10-29 A/m, and the Koenigsberger ratio - within 5.5-16.

To interpret the HMS data, 2.5-dimensional modeling was performed according to the method proposed in the work. As a priori information, the materials of the echo-sounding sounding and NSP were used. One of the most realistic models, in which the best coincidence of the curves of the anomalous and model magnetic fields is observed, is shown in Fig. 6.

It follows from the modeling results that the anomalous magnetic field in the region of the volcano is mainly due to its construction. The role of the deep roots of the volcano is very insignificant. The rocks that make up the volcanic edifice have a direct magnetization and are quite homogeneous in composition, which is in good agreement with the geological sampling data. Modeling performed by two other independent methods gave similar results.

Comparing the modeling results with the NSP and echo sounding data, and taking into account the freshness of the dredged material, it can be assumed that, most likely, the sedimentary sequence was cut through during the formation of the volcanic edifice. The base of the volcano apparently began to form in the Pliocene, while the main part of the edifice formed in the Pleistocene.

The underwater volcano Smirnov is located 12 km north-north-west of about. Macanrushi (see Fig. 21). Its base merges with the base of Macanrushi Island at a depth of about 1800 m. Slopes about. Makanrushi are covered with a thick (up to 0.5 s) cover of "acoustically opaque", probably volcanogenic and volcanogenic-sedimentary deposits. The same deposits overlap the southern part of the base of the Smirnov volcano and, as it were, “flow around” it from the southwest and southeast. From the north, the foot of the volcano is blocked by sedimentary deposits typical for this region of the Sea of ​​Okhotsk, at least 1000 m thick. According to available estimates of the rate of sedimentation in the Sea of ​​Okhotsk, it would take at least 5 million years for the formation of this sequence.

The flat top of the volcano is located at a depth of 950 m and is covered with horizontally layered sediments 100-150 m thick. The maximum size of the base of the volcano is 8 11 km, with an area of ​​~ 70 km 2, and a flat top - 2? 3 km. The relative height of the volcanic edifice is 850 m, and its volume is about 20 km 3 .

The underwater Smirnov volcano also clearly manifests itself in the magnetic field, and a magnetic field anomaly with an amplitude of 470 nT is confined to it (see Fig. 21). The volcanic edifice has a direct magnetization.

During the dredging of the Smirnov volcano, various rocks were raised, varying in composition from basalts to dacites.

Dredged andesite-basalts have a residual magnetization of 1.5-4.1 A/m and a Koenigsberger ratio of 1.5-6.9, and andesites - 3.1-5.6 A/m and 28-33, respectively.

To interpret the HMS data, 2.5-dimensional modeling was performed according to the method proposed in . One of the most realistic models, in which the best coincidence of the curves of the anomalous and model magnetic fields is observed, is shown in Fig. 6. The discrepancy at the beginning of the profile of the observed and calculated curves of the anomalous magnetic field is due to the influence of the nearby Makanrushi Island. It follows from the simulation results that the anomalous magnetic field in the region of the volcano is due to its structure, and not to deep roots. Despite the heterogeneity of the dredged material, the vast majority of the structure is rather homogeneous in composition of its constituent rocks, which have a direct magnetization. Based on the magnitude of the effective magnetization, such rocks can be high-potassium amphibole-bearing andesites, typical of the rear zone of the Kuril-Kamchatka island arc.

The flat top of the volcano indicates that it once rose to sea level, and then experienced a significant subsidence. Extensive underwater terraces about. Makanrushi are located at depths of about 120-130 m. This practically corresponds to the sea level in the late Pleistocene, i.e. no significant subsidence has occurred in this area since the late Pleistocene. Therefore, we can assume that the lowering of the flat top of the Smirnov volcano to a depth of 950 m occurred before the beginning of the Late Pleistocene. The nature of the relationships between the Smirnov volcano edifice and the sedimentary deposits of the bottom of the Sea of ​​Okhotsk and the deposits of the submarine slopes of Okhotsk Island. Makanrushi suggests that this volcano is one of the most ancient parts of the massif about. Macanrushi. Its age is at least Pliocene.

The Kuril Islands is a 1200-kilometer chain of 56 islands stretching from the Kamchatka Peninsula to the Japanese island of Hokkaido. They form two parallel ridges, which are called the Greater Kuril and Lesser Kuril.

All islands are part of Sakhalin region RF. Many of them have rich and picturesque nature. There are many volcanoes here.
There is evidence of fighting with the Japanese in 1945. The economy of a few settlements is mainly associated with fishing and fish processing. These places have a huge tourist and recreational potential. Several islands in the South Kuriles are disputed by Japan, which considers them part of Hokkaido Prefecture.

In the northern part of Iturup Island on the coast of the Sea of ​​Okhotsk, there are unusual volcanic phenomena called the White Rocks. They are composed of pumice or a glass-like porous mass and stretch for 28 kilometers.

The ridges created by nature have a fantastic view and are cut by beautiful canyons. The shore near them is a beach covered with white quartz and black titanomagnetite sand. The sight of such an extraordinarily beautiful natural object leaves a lasting impression.

On one of the islands there is an unusually beautiful bay called Crater. It is a biological reserve. Its uniqueness lies in the isolation of flora and fauna from the surrounding nature. Here, along with sea urchins living at the bottom, several new species of animals have been discovered.

South-facing bay deep 56 meters has a shallow entrance width of 300 meters and protrudes into the island for a kilometer. A 388-meter volcano operates in the bay Ushishir, the picturesque slopes of which are covered with dense vegetation, descending directly to the water.

This island volcano is the highest active volcano on the islands. Its height is 2339 meters and the correct shape of the cone, which is often compared with the outlines of the Japanese volcano Fuji.

At the base and on the slopes there are more than three dozen cinder cones. The volcano is located 70 kilometers from the Kamchatka coast and 30 kilometers from the largest North Kuril island, Paramushir. It is classified as a double stratovolcano, on top of which there is an explosive crater 200 m deep and up to 1300 m in diameter.

The city of Severo-Kurilsk, located on the island of Paramushir, is its administrative center. 2587 people live in it. After the war, fish processing plants operated here on the basis of former Japanese enterprises.

Residential buildings, schools, hospitals, etc. were built. In 1952, a tsunami with a wave height of 10 meters that arose as a result of an earthquake destroyed the city and surrounding settlements. In the 60s of the last century, the city was restored.

In 1982, on some of the islands belonging to the Lesser Kuril Ridge, a federal natural state reserve was founded. Its purpose is to increase the number and conservation of rare birds and marine animals.

Among them are Red Book birds, as well as local sea otters, seals, sea lions, northern fur seals, killer whales, gray dolphins and humpback whales. Most of the reserve is occupied by coniferous and broad-leaved forests. On its territory there are nesting places for sea birds and a rookery for a seal listed in the Red Book.

In the south of the island Iturup a natural reserve has been created, where there are two volcanoes, three mountain ranges, isthmuses, large picturesque lakes and many streams. Spruce and mixed forests covering the island are extraordinarily beautiful. In them great amount mushrooms and berries, there are thickets of bamboo.

There are unique plants like the huge Sakhalin champignon. In Lake Krasivoye, which is 48 meters deep, salmon spawn. You can get to the reserve through a small airport and a pier in Kasatka Bay.

This unique place on the planet got its name due to its ring-shaped form surrounding the Krenitsyn volcano, which is considered one of the largest in the world.

The lake with a volcano is located on a quiet and calm uninhabited island of Onekotan. The depth of the reservoir does not exceed a meter. it perfect place for connoisseurs of untouched nature who admire the surrounding landscapes while climbing a huge volcano.

This small island-volcano with a constantly smoking upper cone has a square shape with a side of 3.7 kilometers.

The island is almost impregnable because of the rockiness, you can moor to it only by boat in one place in the absence of wind and waves. At the same time, you need to focus on a beautiful 48-meter rock. The vegetation is sparse, there are mosses and grasses, alder bushes. Hundreds of thousands of birds gather here for bird markets.

This is the name of the border and southernmost of the Kuril Islands. It is separated from Japan by two straits. The city of Yuzhno-Kurilsk is its main settlement. In fact, the island consists of a chain of volcanoes, which bear the names of Golovin, Mendeleev and Tyat.

They are connected by washed sandstone. The island has rich flora and fauna. There are many thermal springs, unique volcanic lakes. One of them - Boiling, is considered the main South Kuril attraction.

This island is the largest in the northern part of the Kuriles. Its length about 120 kilometers, a width of about 30. It has a rich relief, consisting of mountain ranges, which are a chain of volcanoes, some of which are active. There are many grassy meadows, many rivers, streams and lakes.

The forests are predominantly willow. Wild rosemary and rhododendrons bloom beautifully, there are a lot of lingonberries, blueberries and other berries. Salmon fish live in the large river Tukharka. You can meet brown bears, hares, rodents, sea otters, sea lions and seals.

This North Kuril island was an important military facility of the Japanese army. It housed an 8.5 thousandth garrison with aircraft, tanks, guns, mortars, underground fortifications.

This 15 km strait connects the Sea of ​​Okhotsk with the Pacific Ocean. He received the name of the Russian naval officer I.F. Kruzenshtern, who first walked along it in 1805 on the Nadezhda sailboat.

The strait is picturesque, along it there are uninhabited rocky and steep islands, and in the center there are the Trap rocks dangerous for sailors. At its narrowest point, it is 74 kilometers wide. With a maximum depth of 1764 meters, there are two 150-meter shallows.

There are unique thermal springs and reservoirs on the slopes of the Baransky volcano. On a rocky plateau there is a geothermal station that generates electricity.

There are geysers, lakes, sulfur streams, baths with boiling mud. In the lake with the name "Emerald Eye" the temperature reaches 90 degrees. It feeds the picturesque four-kilometer-long rapids river Boiling with hot and sour water.

In one place, it ends with an incredibly beautiful 8-meter waterfall, the water temperature in which is 43 degrees.

21 active volcanoes are known on the Kuril Islands, of which five stand out for their more active activity, among the most active volcanoes of the Kuril ridge, these include Alaid, Sarychev Peak, Fuss, Snow and Milna.

Among the active volcanoes of the Kuril Islands, the most active volcano is Alaid. It is also the highest among all the volcanoes of this ridge. As a beautiful cone-shaped mountain, it rises directly from the sea surface to a height of 2,339 m. At the top of the volcano there is a small depression, in the middle of which the central cone rises.

It erupted in 1770, 1789, 1790, 1793, 1828, 1829, 1843 and 1858, that is, eight eruptions in the last 180 years.

In addition, near the northeastern shores of Alaid, an underwater eruption occurred in 1932, and in December 1933 and January 1934, eruptions occurred 2 km from its eastern shore. As a result of the last eruption, a volcanic island with a wide crater was formed, called Taketomi. It is a side cone of the Alaid volcano. Taking into account all these eruptions, we can say that over the past 180 years, at least 10 eruptions have occurred from the Alaid volcanic chamber.

In 1936, a spit formed between Taketomi and Alaid volcanoes, which connected them. The lavas and loose volcanic products of Alaida and Taketomi are basaltic.

Sarychev Peak is in second place in terms of the intensity of volcanic activity and is a stratovolcano located on the island of Matua. It has the form of a two-headed cone with a gentle slope in the lower part and with a steeper one - up to 45 °, in the upper part.

On the higher (1497 m) peak there is a crater with a diameter of about 250 m and a depth of about 100 - 150 m. There are many cracks near the crater on the outer side of the cone, from which white vapors and gases were emitted (August and September 1946).

On the south side, the cliff surrounds Sarychev Peak in a semicircle, which, most likely, is a remnant of the crest of the original volcano. To the southeast of the volcano are, apparently, small secondary cones.

From the 60s of the XVIII century to the present, its eruptions occurred in 1767, around 1770, around 1780, in 1878-1879, 1928, 1930 and 1946. In addition, there are numerous data on its fumarole activity. So in 1805, 1811, 1850, 1860. he "smoked". In 1924, an underwater eruption occurred near it.

Thus, over the past 180 years, there have been at least seven eruptions. They were accompanied by both explosive activity and outpourings of basaltic lava.

The last eruption occurred in November 1946. This eruption was preceded by a revival of activity of the neighboring volcano Rasshua, located on the island of the same name. On November 4, it began to rapidly emit gases, and a glow was visible at night, and from November 7, an increased release of white gases from the crater of the Sarychev Peak volcano began.

On November 9, at 17:00, a column of gases and black ash rose above its crater, and in the evening a glow appeared that was visible all night. During November 10, ash was thrown out of the volcano and light, but frequent tremors occurred, and an uninterrupted underground rumble was heard, and occasionally thunder peals.

On the night of November 11-12, mainly hot bombs were thrown to a height of up to 100 m, which, falling along the slopes of the volcano, cooled rather quickly. From 22:00 12 to 14 November, the eruption reached its maximum stress. First, a huge glow appeared above the crater, the height of the flight of volcanic bombs reached 200 m, the height of the gas-ash column - 7000 m above the crater. Particularly deafening explosions occurred on the night of the 12th to the 13th and on the morning of November 13th. On November 13, the outpouring of lava began, and side craters formed on the slope.

The eruption was especially beautiful and spectacular on the night of November 13 and 14. Fiery tongues descended from the crater down the slope. The entire top of the volcano, 500 m down from the crater, seemed red-hot from a large amount of ejected bombs, debris and sand. From the morning of November 13 to 2 pm on November 14, the eruption was accompanied by various types of lightning, which almost every minute sparkled in different directions.

The Fussa Peak Volcano is located on the island of Paramushir and is a separate beautiful gkonus, the western slopes of which abruptly break into the Sea of ​​Okhotsk.

Fuss Peak erupted in 1737, 1742, 1793, 1854 and H859, and the last eruption, i.e., 1859, was accompanied by the release of asphyxiating gases.

Snow Volcano is a small low domed volcano, about 400 m high, located on Chirpoy Island (Black Brothers Islands). At its top (there is a crater about 300 m in diameter. In the northern part of the bottom of the crater there is a depression in the form of a well, with a diameter of about 150 m. Numerous lava flows erupted mainly to the south of the crater. Apparently, it belongs to shield volcanoes. It is known an indication without an exact date of the eruption of this volcano in the 18th century.In addition, Snow volcano erupted in 1854, 1857, 1859 and 1879. Miln volcano is located on Simushir Island, is a two-headed volcano with an inner cone 1,526 m high and bordering on the western side parts of the ridge - the remains of a destroyed more ancient volcano, 1,489 m high. Lava flows are visible on the slopes, which in some places protrude into the sea in the form of huge lava fields.

There are several side cones on the slopes, of which one, called the "Burning Hill", acts along with the main cone and, thus, is, as it were, an independent volcano.
There is information about the volcanic activity of the Milna volcano dating back to the 18th century. According to more accurate information, it erupted in 1849, 1881 and 1914. Some of them, in all likelihood, refer only to the eruptions of the Burning Hill.

Less active volcanoes include Severgin, Sinarka, Raikoke and Medvezhiy volcanoes.

The Kuriles are the place where the End of the World is located, in any case, that's what it is called cape on Shikotan. The mysterious archipelago keeps a lot of unusual things - this is the Udachny stream with outcrops of quartz gold, the largest waterfall in Russia (140m) Ilya Muromets, and fire-breathing islands with volcanoes and geysers. The Kuriles are compared with a large arboretum, where you can visit various natural areas, and where stone birches, lianas, cedar elfin and bamboo thickets coexist, exceeding the height of a person. Large bird markets, bears, sables and foxes, whales and dolphins, underwater inhabitants - seals, squids, crabs and starfish - all this can be seen while traveling through these pristine islands.

Thermal springs are attractive for the traveler, volcanoes Alaid, Chikurachki, Fussa, Ebeko and others; and military history will reveal to you the secrets of its past during the Kuril landing in 1945.

Great Kuril Ridge- one of two parallel groups of islands of the Kuril archipelago. The Krusenstern and Bussol straits divide it into three parts:

The northern group includes the islands of Paramushir, Onekotan, Shumshu, Traps, Atlasova, Shiashkotan and others;
- middle - Simushir, Ketoi, Rasshua, Matua, Ushishir and others;
- the southern group includes the islands of Iturup, Kunashir, Urup.

The territory of the islands is unevenly populated and is uninhabited south of the island of Paramushir and up to the island of Iturup. In this regard, tourist routes mainly run along the islands of the Northern and Southern Kuriles. The most popular are Iturup, Paramushir, Shikatan, Shumshu, Kunashir, Matua.

Northern Kuriles

Severo-Kurilsk is the main city of this group of islands. Until 1946, it was called Kashiwa-bora. The city is located on the shores of the 2nd Kuril Strait in the northeast of Paramushir Island. Its population is 2400 inhabitants (data for 2007). The seiner fleet is based here, there is a heliport, and the total length of roads is about 10 km.

The islands can only be reached by helicopter from Petropavlovsk-Kamchatsky or by PTR ship. The main types of tourism include historical and educational and ecological. The remoteness of the islands is still an obstacle to mass tourism. However, thermal springs, military routes, volcanoes and unusual flora and fauna of the Kuriles are attractions that attract an increasing number of tourists.

The volcanoes of the Kuril Islands are part of the Pacific Ring of Fire.

Ebeko Volcano (1156m). This active volcano is located on Paramushir Island, 7 km from Severo-Kurilsk. Being one of the most active on the Kuril Islands, it is interesting for the presence of several craters. On the southern part of the cone is an active crater that appeared after the eruption in 1965. In the northern part, in the crater is located small lake with greenish water. Known in literature, the North Crater was filled with cinders and volcanic bombs during the last eruption. And another one - the central one - is filled with a lake, which is replenished with water from a snowfield. Once the lake was hot, but later lost contact with underground heat sources. Climbing the Evbeko volcano, you can see a Japanese sulfur plant and many fumaroles. These are holes through which gases rise. Each fumarole is surrounded by intricate figures made of native sulfur. Among the large fumarole fields, the northeastern field stands out, known as the "Roaring Fumaroles" or "White Key".

Volcano Alaid (2339m). It is the highest active volcano in the Kuril Islands. It is located on Atlasov Island, 70 km from Kamchatka and 30 km from Paramushir Island. According to legend, Alaid used to be located in the south of Kamchatka. But other mountains drove him away, because he was the highest among them and blocked the light. Since then, the volcano-island has stood alone. The shape of the Alaid cone is more correct than Mount Fuji. Its feature is the presence of 33 secondary cinder cones on the slopes and at the base. Intense fumarolic activity takes place inside a young 250-meter cinder cone. Alaid is a double stratovolcano with a summit explosive crater 900-1300m in diameter and 200m deep.

Volcano Chikurachki (1816m) – highest point Paramurshir, located in the southwestern part of the island, 60 km from Severo-Kurilsk. In the chain of volcanoes of the Karpinsky Ridge, it is the northernmost. Chikurachki is a stratovolcano standing on an ancient lava base, with a regular cone, the upper half of which is red. It is mainly composed of pyroclastic deposits.

Fussa Volcano (1772m). This complex stratovolcano forms a peninsula in the southwestern part of Paramushir Island, 75 km from Severo-Kurilsk. It is a strongly truncated regular cone with a crater 700 m in diameter and up to 300 m deep. The crater has steep walls, steep in places, and the bottom, divided into two unequal parts, is dotted with snowfields. The volcano offers a breathtaking view of the rocky outcrops of the Arkhangelsky and Belousov mountains, the gentle slopes of the Karpinsky caldera and the saddle between the Lomonosov and Tatarinov volcanoes.

Shumshu and Matua islands. These islands are especially interesting to visit from a historical and educational point of view. They are famous for the catacombs of the war years and preserved fortifications, including numerous trenches, bunkers and rock holes, where the personnel of the garrison of the islands took refuge and guns were installed.

Southern Kuriles

The most easily accessible and interesting to visit in this part of the Kuriles are the islands of Kunashir and Iturup. You can get to them by air from Yuzhno-Sakhalinsk or by boat from Korsakov. Due to constant fog and weather changes, the An-24 aircraft, which flies three times a week, can wait quite a long time for the right weather. Therefore, the ship is a more reliable way to travel, although due to weather conditions can also change the schedule of arrival to the islands. It is obligatory to visit the South Kuriles to issue a pass in Yuzhno-Sakhalinsk, since the islands are located in the border zone.

Kunashir Island. This is one of the largest and most south island Greater Kuril Ridge with the administrative center in Yuzhno-Kurilsk. In fact, it is a chain of volcanoes - Tyatya, Mendeleev, Golovnin volcano, which are connected by washed sandstone. The Kunashirsky and Treason Straits separate the island from Japan. Many thermal springs and waterfalls are also popular with travelers. Another place worth visiting is the caldera of the Golovnin volcano, where two lakes lie - Hot and Boiling. The latter, formed in an explosive funnel, is considered the hallmark of the South Kuriles. The lake is famous for the fact that a boiling steam-water jet can suddenly hit from its bottom.

Cape Stolbchaty- This is one of the main attractions of Kunashir. Located on the shores of the Sea of ​​Okhotsk, it was formed in the process of pouring lava into the water column. Tall basalt pillars create ribbed walls, resembling a giant organ. Another highlight of the cape is salmon spawning, which you can follow for hours, watching the fish overcome waterfalls, rapids and streams on the way to the spawning ground.

Iturup Island. This is the most large island archipelago. From the east it is washed by the Pacific Ocean, from the west by the Sea of ​​Okhotsk. Of the 20 volcanoes on the island, 9 are active, and the highest is Stockap, 1634 meters in height. On Iturup, it is recommended to visit the Lion's Mouth Bay and three volcanoes - Berutarube, Atsonopuri and Curly. There are also more than 30 lakes, many waterfalls, hot and mineral springs.

Volcano Berutarube (1222m). In both craters of the volcano, active fumarolic activity takes place. At the top there is a destroyed caldera with a diameter of more than 2 km.

Volcano Atsonopuri (1205m). Due to the high porosity of the slag hallmark islands became a complete lack of water. Atsonopuri is the so-called “volcano within a volcano”, which extends far into the open sea. The correctness of the cone allowed him to take 3rd place in the world after Fujiyama and Vesuvius.

Volcano Curly (991m). It is an active volcano, with a dome in the shape of an isosceles triangle. The height of vertical columns of gas and steam above the crater in calm weather reaches 1 kilometer. In addition, here is the only place in the world where rhenium, a rare earth metal, is mined.

Lion's Mouth Bay. Located in the southwestern part of Iturup, the bay (caldera) resembles a broken ring. The dimensions of the caldera are 7 x 9 km, and its rocky shores rise up to 400 meters. In the strait, at the entrance to the bay, there is a rocky island - Lion Stone, resembling a sleeping lion. The two capes jutting out into the sea are called Fang and Jaw.

But back to active volcanoes. In the Soviet Union, the region of active volcanoes lies in the east, at the very borders of our country. This region, illuminated by the fires of eruptions, is Kamchatka and the Kuril Islands. There are 129 volcanoes in Kamchatka. They form an almost continuous volcanic belt stretching along the eastern coast of the peninsula.

29 volcanoes are active or fell asleep for a while, the rest are considered extinct.

Sheveluch volcano rises in the north of the Kamchatka volcanic belt. To the south of Sheveluch, in the right-bank part of the Kamchatka River basin, is the famous Klyuchevskaya group of volcanoes. It contains and highest volcano Eurasia - Klyuchevskaya Sopka. Further south, a strip of active and extinct volcanoes stretches for several hundred kilometers. In the vicinity of the city of Petropavlovsk, Avachinskaya Sopka concludes this strip. Finally, in the very south of the peninsula, in the family of dormant and extinct volcanoes, there is another interesting volcano - Ksudach, dormant for more than 50 years. In the past, apparently, it was one of the largest volcanoes in the south of Kamchatka.

In 1935, at the foot of Klyuchevskaya Sopka in the village of Klyuchi, the Volcanological Station of the USSR Academy of Sciences was built. Since that time, for more than a quarter of a century, volcanologists have been continuously monitoring Kamchatka volcanoes. Researchers have collected rich material on the nature of eruptions, on changes in the activity of volcanoes, on the temperature and composition of their lavas.

It turned out that the volcanoes of Kamchatka are very diverse. Almost everyone has their own characteristics, svchzh "temper". Sheveluch by the nature of the eruptions is a brother of the Martinique volcano Mont Pele and the Indonesian Merapi. The closest "relatives" of the Klyuchevskoy volcano, similar in behavior, are found in Italy. This is Etna and the volcanoes of the environs of Naples.

The lavas of Sheveluch, the northernmost of the Kamchatka volcanoes, are very viscous and contain a huge amount of vapors and gases. During eruptions, they do not form streams flowing down the slope of the volcano, but are slowly squeezed out of the crater and piled up above it in the form of a dome. During the 1945 eruption, lava squeezing was accompanied by strong explosions that shook the neighborhood for tens of kilometers around. During the explosions, clouds of hot gases escaped from under the lava dome. These clouds contained a huge amount of small lava particles. With tremendous speed, they rolled down the slopes of the volcano and burned everything in their path. Sheveluch eruptions make themselves felt at a great distance. On a fine September day in 1964, we were at the foot of the Klyuchevskoy volcano. The path passed through flat terrain, in some places cut through by valleys of "dry" rivers. Here and there there were glacial boulders, and even huge blocks, covered with black-gray volcanic ash, born from the eruptions of the Klyuchevskoy volcano. It was a kind of stony ash desert. Ashes easily rose into the air and clouds of volcanic dust remained behind the traveler. But in the cliff of the valley of the Apakhonchich stream, among the ash, sand and gravel deposited by water, something else was visible. Against the background of this dark gray mass, two layers of yellowish-gray volcanic ash were clearly distinguished (Fig. 23), completely unlike the ash of Klyuchevskoy volcano. This is the ashes of Sheveluch. The upper layer arose during an eruption in the middle of the last century. The distance that the ash was carried from the volcano to the place of its burial in a straight line is about 60-70 km.

Volcanoes of the Klyuchevskaya group behave differently during eruptions. This group consists of twelve volcanic cones. All of them are located on the same lava pedestal, apparently representing the remains of a huge, more ancient volcano. The largest and most active volcano of this group is Klyuchevskoy. He is rightfully considered a handsome volcano. Its high, regular cone is crowned with a constantly smoking or white peak illuminated by the reflections of fire (Fig. 24). Like a gigantic, ice-bound lighthouse, it is visible from the sea at a distance of several hundred kilometers.

At the top of the Klyuchevskoy volcano there is a huge bowl-shaped depression - a crater with a diameter of about 0.5 km. In the depths of the crater, deep channels darken, going into the bowels of the volcano. Clubs of dark and white vapors, clouds of ash and hot stones break out from these channels every minute with a roar. When the volcano is calm, the ash and stones rise only to a height of 200-300 m and fall back into the crater.

Employees of the Volcanological Station descended into the crater of the Klyuchevskoy volcano and found that the entire bottom of the crater was covered with loose volcanic ash. Plunging into it knee-deep, volcanologists tried to get to the central channel - the vent. But they failed. Explosions followed one after another, red-hot stones continuously flew from the vent. I had to stop a few tens of meters from the border of falling stones. Then the explosions intensified, "jets" of hot stones rapidly hit from the bowels of the volcano, and the entire bowl of the crater began to quickly cloud over with clouds of dark smoke. The explorers had to retreat.

It was possible to climb to the top of Klyuchevskaya Sopka and descend into the crater at a time when the volcano was relatively calm. And Klyuchevskaya Sopka is famous for the strength and duration of its eruptions. One of the last major eruptions lasted from the end of 1944 until the summer of 1945. When it began, the walls of houses trembled from the roar of explosions at a distance of 50 km from the volcano. Volcanic ash fell all over the peninsula. By the end of the eruption, several large explosion craters formed along the crack, which stretched from the top of the hill to its foot, and a small slag body grew at the lower end of the crack. From it began an outpouring of lava.

Volcanoes like Klyuchevskoy, composed of lava flows and layers of volcanic ash and bombs, are called stratified, or stratovolcanoes. Eruptions gradually increase the height of Klyuchevskaya Sopka. They repeat on average every six to eight years, and each eruption increases the volume of the volcanic cone by about 0.5 km3. Having determined the volume of the cone of the Klyuchevskoy volcano, scientists calculated that it was formed in seven hundred eruptions. Thus, it was established that Klyuchevskaya Sopka is a relatively young volcano. Its formation began about 5000 years ago.

In the center of the Klyuchevskaya group is the Bezymyanny volcano, which for a long time was considered extinct. However, in October 1955, he suddenly woke up. The awakening was unusual and terrible. It began with earthquakes in the vicinity of the volcano. They were followed by explosions, and the volcano began to throw out ash. The amount of ash erupted gradually increased, it was carried over a distance of 100 km. In some places, the ash fell so thickly that the sun's rays did not penetrate through its veil. During the day it became as dark as at night.

Then the eruption began to subside, but suddenly, on March 30, 1956, an explosion of monstrous force occurred. A cloud of ash rose to a height of 40 km above the volcano. A jet of hot gases escaped from the crater, which burned and knocked down trees even at a distance of 25 km from Bezymyanny. The top of the mountain and the entire eastern part of the cone were blown up. A red-hot mass of loose material poured into the gap formed from the revived volcano, consisting of volcanic ash and blocks of various shapes and sizes. The ejection of a loose flow of incandescent debris was so rapid that it quickly filled the river valley to a depth of 80-100 m. The flow cooled down for several months, and thousands of jets of hot vapors and gases rose from its surface.

As a result of the explosion of Bezymyanny, volcanic ash was carried to a distance of 400 km in a radius, and the volcano itself dropped by almost a third of a kilometer. At its top, a giant crater appeared in the form of a semicircle, open to the east. Such large depressions formed during volcanic explosions are called calderas. After the explosion, viscous lava began to gradually squeeze out from the bottom of the Bezymyanny volcano caldera, which by the end of the eruption formed a dome about 300 m high.

The eruption of Bezymyanny lasted almost a year and ended only in the fall of 1956. It was calculated that the explosion on March 30, 1956 released a colossal amount of energy, equal to approximately 4 10 23 ergs. This amount of energy is generated by the Kuibyshevskaya HPP during the year. The force of the air wave was monstrously enormous, and its initial speed was almost twice the speed of sound. Apparently, the Nameless eruption was one of the strongest volcanic explosions ever observed by people.

In subsequent years, the activity of Bezymyanny manifested itself only in the summer, mainly in the growth of the dome and the formation of stone obelisks on it. In the early autumn of 1964, we were able to see for ourselves the increased activity of the volcano. On the southeastern slope of the crater, two pointed gray obelisks were squeezed out. At night, a fiery glow could be seen above the obelisks. Collapsed and hot pyroclastic avalanches rolled down the slope, which, like a chisel, cut through a deep and narrow cavity-slit on the slope of the volcano. Here and there, lava was showing through the cracks. Judging by the color, its temperature was about 900°C. On September 9, 1964, the activity of Bezymyanny began to decrease, but in the following September days, dark smoky clouds up to 3-4 km high rose above the volcano.

Avachinsky volcano, like Klyuchevskoy, is also layered. Its eruptions are very similar in nature to the eruptions of Mount Vesuvius, located in the vicinity of Naples. The last major eruption of Avacha Sopka occurred in the winter of 1945. It lasted less than a day. After several strong explosions, a black mushroom-shaped ash cloud several kilometers high rose above the cone of the volcano. It swirled, lit up with crimson reflections, volcanic bombs flew from it, and ash fell. Bombs and hot ash melted the snow at the top of the volcano, and swift streams of hot water and mud rushed from the slopes of the mountain. Then the ash cloud began to dissipate, and the volcano subsided.

Ksudach, located in the south of Kamchatka, is a volcano-caldera. Once upon a time he was large volcano with a diameter of about 20 km, but during one of the eruptions, its cone was destroyed by a strong explosion. A funnel-shaped basin-caldera with a diameter of 8 km was formed, surrounded on all sides by a low ring-shaped ridge. Inside the ring there is now a lake, along the banks of which numerous pairs of fumaroles rise.

The last eruption of the Ksudach volcano occurred in 1907. It began with a strong explosion and the release of a huge amount of ash. Fine volcanic dust rose into the stratosphere and was carried away tens of thousands of kilometers from the volcano. As a result of the explosion, a new funnel appeared inside the caldera itself, with a diameter of about 1.5 km, with almost sheer walls. Soon a lake also formed in this smaller, inner caldera.

In addition to volcanoes, there are many geysers in Kamchatka - boiling springs, periodically ejecting fountains of hot water. There are about twenty large and at least a hundred small geysers in the valley of the Geysernaya River. The water temperature in them reaches 94-98°C. The largest geyser - "Giant" - throws out giant jets of water to a height of 40-50 m every 3-4 hours.

The abundance of vapors released during volcanic eruptions, a huge number of geysers and hot springs indicate that huge reserves of superheated steam and hot water are hidden in the depths of the Kamchatka Peninsula, which can easily be used for human needs. In the land of volcanoes in Iceland and in the vicinity of Naples in Italy, people are already using the volcanic heat of the bowels. Hot steam coming from hundreds of boreholes turns turbines in power plants, heats houses, drives machines in factories. And in Kamchatka we have begun drilling test wells to produce hot water and steam. They will be used for heating and for technical purposes at fish canning plants.

The volcanoes of the Kuril Islands are a continuation of the belt of Kamchatka volcanoes. The Kuril arc stretches for 1200 km between the southern tip of Kamchatka and the Japanese island of Hokkaido. The underwater ridge, the peaks of which are the islands of the Kuril arc, serves as the boundary separating the Sea of ​​Okhotsk from the vast expanses of the Pacific Ocean. There are 61 extinct and 39 active volcanoes on the islands of the Kuril arc. The most active of them are Alaid, Ebeko, Krenitsina, Mendeleev volcanoes, etc.

The largest of the Kuril volcanoes is Alaid. Its top, crowned with a small glacier, rises to 2300 m above sea level. People have seen this volcano erupt more than once. The last eruption of Alaid was in 1932. It did not occur through the main crater, but through a crack in the underwater part of the volcano. As a result of this eruption, a smoking island appeared in the sea, which turned out to be the side cone of Alaid. The cone had its own crater. A few years after the end of the eruption, the island was connected by sandy spits to the parent island and turned into the Alaida Peninsula.

In the autumn of 1952, the Krenitsina volcano, located on Onekotan Island, one of the northern Kuril Islands, woke up after a long sleep. The volcano is located in the southern part of the island in an ancient caldera. The cone of the Krenitsina volcano rises from the blue waters of the lake, which fills the wide funnel-shaped caldera bowl. The eruption began with a roar that was heard at a distance of 100 km from the volcano. From the waters blue lake clouds of steam rose, then a cloud of ash rose over the island and hid the volcano with an impenetrable veil. Ashes fell throughout the day, thickly covering the island. At night, a fiery glow appeared over the crater. Clouds of ash, illuminated by the reflections of the eruption and bright flashes of lightning, the wind carried into the ocean. From a distance, from the passing steamers, it seemed that a fiery whirlwind was escaping from the depths of the ocean. A few days later, the eruption gradually began to weaken, and a week after awakening, the volcano calmed down again and has been sleeping for more than ten years.

The volcanoes of Kamchatka and the Kuril Islands are associated with huge faults in the earth's crust. A whole belt of such faults borders the Pacific Ocean. Molten masses of sub-crustal matter - magma - rise from the depths of the Earth along the cracks of the faults. Volcanoes, Sheveluch, Klyuchevskaya Sopka, Bezymyanny, Ksudach, Alaid, Krenitsina volcano and the rest 233 extinct, dormant and active volcano The Kuril-Kamchatka arc is only a small part of the Great Fiery Pacific Ring, which has hundreds of underwater and surface volcanoes. The amazing accumulation of volcanoes around the Pacific Ocean and at its bottom is one of the many mysteries of geology. To unravel this mystery, geologists of future generations will have to penetrate the bottom of the Earth's greatest ocean. And when the ocean floor is studied at least with the same detail with which geologists have currently studied the earth's continents, the mystery of the Pacific Ring of Fire, which contains more than two-thirds of the Earth's volcanoes, will probably be close to being solved.