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GS Paper: GS1-15.Geographical features and their location- Changes in critical geographical features (including water-bodies and ice-caps) and in flora and fauna and the effects of such changes.

  • Palghat Gap: A break in the Western Ghats

    palghat

    Central Idea: The article discusses the Palghat (Palakkad) Gap, a significant corridor in the Western Ghats of India. It provides information about the geological origin of the gap.

    What is Palghat Gap?

    • The Palghat Gap is a 40 km wide corridor in the Western Ghats, known for its steep hills and serving as a gateway to Kerala.
    • It is a crucial passage for roads and railways connecting Coimbatore and Palakkad.
    • The Bharathappuzha River flows through the Palghat Gap.
    • The vegetation in the gap is classified as dry evergreen forest, different from the tropical rainforests of the Western Ghats.
    • The Palghat Gap marks a distinct divide in the flora and fauna of the region.

    Geological origin of the Palghat Gap

    • The Palghat Gap is a geological shear zone running from east to west.
    • Shear zones are weak regions in the Earth’s crust, occasionally causing tremors in the Coimbatore region.
    • The formation of the Palghat Gap occurred when the continental shelves shifted after the separation of Australia and Africa from the Gondwana landmass.
    • India and Madagascar were connected until volcanic activity led to their split, with a similar gap called the Ranotsara Gap in Madagascar.

    Biogeographic distinctions and ancient history

    • The biogeographic distinctions in species north and south of the Palghat Gap may be attributed to an ancient river or an incursion of the sea in the distant past.
    • Elephant populations on the Nilgiris side of the gap have different mitochondrial DNA from elephants in the Anamalai and Periyar sanctuaries.
    • DNA analysis of the White-bellied Shortwing, an endemic bird species, shows divergence between populations in the Nilgiris and the Anamalai regions.

    Biodiversity south of the Palghat Gap

    • The southern region of the Western Ghats, located south of the Palghat Gap, exhibits high species richness and phylogenetic diversity.
    • A recent study reports over 450 tree species, including ancient species like Magnolia champaca, dating back 130 million years.
    • The warm weather and moist air of the southern Western Ghats support a diverse range of life, making it an island refuge during cycles of ice ages and droughts.
    • The southern Western Ghats receive rainfall more evenly throughout the year compared to the northern region.

    Back2Basics: Western Ghats

    • The Western Ghats, also known as the Sahyadri mountain range, is a UNESCO World Heritage Site and one of the 36 biodiversity hotspots in the world.
    • It spans an area of 160,000 sq. km. and stretches for 1,600 km parallel to the western coast of the Indian peninsula, passing through the states of Gujarat, Maharashtra, Goa, Karnataka, Kerala, and Tamil Nadu.
    Description
    Flora and Fauna The Western Ghats are home to a rich diversity of flora and fauna, including over 7,402 species of flowering plants, 1,814 species of non-flowering plants, 139 mammal species, 508 bird species, 227 reptile species, 179 amphibian species, 290 freshwater fish species, and 6,000 insect species.
    Geological Significance The Western Ghats, known as the “Great Escarpment of India,” are older than the Himalayas. They influence India’s monsoon weather patterns by intercepting rain-laden monsoon winds from the southwest during late summer.
    Geographic Features Stretching north to south along the western edge of the Deccan Plateau, the Western Ghats separate the plateau from the narrow coastal plain called the Western Coastal Plains, which lies along the Arabian Sea.
    Catchment Area The Western Ghats cover a vast catchment area for complex riverine drainage systems, contributing to almost 40% of India’s total drainage. The range acts as a barrier, blocking southwest monsoon winds from reaching the Deccan Plateau.

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  • Over 19,000 Seamounts discovered

    seamount

    Central Idea: Scientists have reported finding 19,325 new seamounts after poring through new high-resolution data. A study had already mapped 24,000 seamounts across the world’s oceans.

    Why study this?

    • The recent discovery of new seamounts was made possible by advancements in altimetry for gravity-field mapping, which improved spatial coverage.
    • The CryoSat-2, Envisat, Jason-1 geodetic missions, and the SARAL satellite developed by India and France contributed to these advancements.

    What are Seamounts?

    • Seamounts are underwater mountains formed through volcanic activity.
    • They are recognised as hotspots for marine life.
    • Most seamounts are formed near mid-ocean ridges, intraplate hotspots, and oceanic island chains with volcanic and seismic activity called island arcs.
    • They can be active, extinct or dormant volcanoes.

    Importance of Seamounts

    • Seamounts provide information about the mantle’s composition and how tectonic plates evolve as they are formed when molten rock comes up from below the tectonic plates.
    • Oceanographers study seamounts to understand their influence on how water circulates and absorbs heat and carbon dioxide.
    • Seamounts are home to diverse biological communities as they can cause localised ocean upwelling, which brings nutrient-rich water from deep within the ocean to the surface.

    How were they mapped?

    • Surveyors map seamounts using either echo sounders or multibeam sonar on ships for topographic mapping or using satellite altimetry for gravity-field mapping.
    • The hi-res maps produced by multibeam sonar mapping are often incomplete, whereas the low-res maps produced by satellite altimetry have better coverage.

     

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  • What is Ningaloo ‘Hybrid’ Solar Eclipse?

    ningaloo

    A ‘hybrid’ solar eclipse called the Ningaloo Eclipse recently happened on April 20, 2023.

    Ningaloo ‘Hybrid’ Solar Eclipse

    • It was a rare astronomical event that occurred on April 20, 2023.
    • The Moon passed directly between the Sun and the Earth, casting a shadow on a narrow strip of land in Western Australia.
    • It was a “hybrid” eclipse, starting as an annular eclipse and transitioning into a total eclipse.
    • The path of the eclipse crossed over the Ningaloo Reef, a world heritage site in Western Australia.
    • It offered a unique opportunity to view the eclipse against the backdrop of the reef and the Indian Ocean.

    How rare are such events?

    • During a solar eclipse, the Moon passes between the Sun and Earth, casting a shadow on Earth’s surface.
    • However, solar eclipses do not occur every month because the Moon’s orbit is tilted by about 5 degrees relative to Earth’s orbit around the Sun.
    • Therefore, the Moon’s shadow usually misses Earth, but occasionally the alignment is just right for a solar eclipse to occur.
    • In the case of the Ningaloo Hybrid Solar Eclipse, the alignment was such that the Moon was at the right distance from Earth to create both an annular and a total eclipse as it moved across the Sun.
    • This type of eclipse is quite rare, occurring only about once every 400 years.

    Back2Basics:

    ningaloo

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  • Zero Shadow Day: What is it, why does it happen?

    shadow

    Central idea: Many cities across India are experiencing Zero Shadow Day since the sun was directly overhead at that time.

    What is Zero Shadow Day?

    • Zero Shadow Day is a phenomenon that occurs twice a year at every point on Earth located between the Tropic of Cancer and the Tropic of Capricorn.
    • During Zero Shadow Day, vertical objects appear to cast no shadow at local noon, when the sun is at its zenith directly above the object.
    • It occurs when the sun’s location moves from 23.5°N to 23.5°S of Earth’s equator and back, causing the shadow to disappear beneath objects at local noon.

    Why does it happen?

    • It occurs due to the movement of the sun from south to north during the Uttarayan and back from north to south during Dakshinayan.
    • This movement is caused by Earth’s rotation axis being tilted at an angle of roughly 23.5° to the axis of revolution around the sun.
    • All places whose latitude equals the angle between the sun’s location and the equator on that day experience Zero Shadow Day, with the shadow disappearing at local noon.

    Try this PYQ:

    On 21st June, the Sun-

    (a) Does not set below the horizon at the Arctic Circle

    (b) Does not set below the horizon at Antarctic Circle

    (c) Shines vertically overhead at noon on the Equator

    (d) Shines vertically overhead at the Tropic of Capricorn

     

    [wpdiscuz-feedback id=”bqrtq7d9ey” question=”Please leave a feedback on this” opened=”1″]Post your answers here.[/wpdiscuz-feedback]

     

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  • Africa’s splitting plates could give birth to a new Ocean: Study

    africa

    Central idea

    • Scientists predict a new ocean will be created as Africa splits into two separate parts connected to the East African Rift
    • This geological process will inevitably divide the continent resulting in new coastlines and sub-sea internet infrastructure but also will have significant repercussions

    What is Rifting?

    • The Earth’s lithosphere, comprising the crust and upper part of the mantle, is divided into tectonic plates that move in relation to each other at varying speeds.
    • Tectonic forces move the plates and can cause them to rupture, resulting in the formation of a rift and potentially leading to the creation of new plate boundaries.
    • Rifting refers to the geological process in which a single tectonic plate is split into two or more plates separated by divergent plate boundaries.
    • In the present day, the gradual separation of the Somali and Nubian tectonic plates is leading to the formation of a rift that could eventually lead to the creation of a new ocean basin.
    • The movement of tectonic plates is a fascinating geological phenomenon.

    Rifting in African Continent

    • The African continent is located on the African Plate, which is one of the Earth’s major tectonic plates.
    • The continent is characterized by a number of geological features, including rift valleys.

    Most profound feature: The East African Rift System

    • The East African Rift System is the most prominent example of rifting in Africa.
    • It stretches for over 6,000 kilometers from the Red Sea in the north to the Zambezi River in the south.
    • The rift system includes a series of interconnected rift valleys, volcanoes, and lakes.

    Causes of the East African Rift System

    • The rift system is caused by the movement of the African Plate away from the Arabian Plate and the Somalian Plate.
    • This movement creates tension in the Earth’s crust, causing it to pull apart and form a rift.

    Impact: Lakes Formed by Rifting

    • Over time, the rifting process has led to the formation of several large lakes in the region.
    • These lakes include Lake Victoria, Lake Tanganyika, and Lake Malawi.
    • They are believed to have formed as a result of the sinking of the land between the rift valleys.

    Future of Rifting in Africa

    • The rifting process is ongoing and may eventually lead to the splitting of the African continent into two or more separate land masses.
    • However, this process is expected to take millions of years and is not likely to have a significant impact on human populations in the near future.
    • The necessary evacuation of people and potential loss of lives will be an unfortunate cost of this natural phenomenon.
    • The emergence of new coastlines will unlock opportunities for economic growth
    • As the plates continue to split in the future, this phenomenon will result in the displacement of communities, settlements, and various flora and fauna.

    Conclusion

    • The movement of tectonic plates has significant implications for the continent’s future.
    • It is important to study and monitor these changes while remembering the power of the Earth’s natural forces and the impact they can have over time.
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  • Earth’s inner core rotating slower than surface: Study

    earth

    Earth’s inner core, a hot iron ball the size of Pluto, has stopped spinning faster than the planet’s surface and might now be rotating slower than it, research suggested.

    A quick recap of Earth’s Interior

    earth

    Structure of earth’s interior is fundamentally divided into three layers – crust, mantle and core.

    [A] Crust

    • It is the outermost solid part of the earth, normally about 8-40 kms thick.
    • It is brittle in nature.
    • Nearly 1% of the earth’s volume and 0.5% of earth’s mass are made of the crust.
    • The thickness of the crust under the oceanic and continental areas are different. Oceanic crust is thinner (about 5kms) as compared to the continental crust (about 30kms).
    • Major constituent elements of crust are Silica (Si) and Aluminium (Al) and thus, it is often termed as SIAL(Sometimes SIAL is used to refer Lithosphere, which is the region comprising the crust and uppermost solid mantle, also).
    • The mean density of the materials in the crust is 3g/cm3.
    • The discontinuity between the hydrosphere and crustis termed as the Conrad Discontinuity.

     [B] Mantle

    • The portion of the interior beyond the crust is called as the mantle.
    • The discontinuity between the crust and mantleis called as the Mohorovich Discontinuity or Moho discontinuity.
    • The mantle is about 2900kms in thickness.
    • Nearly 84% of the earth’s volume and 67% of the earth’s mass is occupied by the mantle.
    • The major constituent elements of the mantle are Silicon and Magnesium and hence it is also termed as SIMA.
    • The density of the layer is higher than the crust and varies from 3.3 – 5.4g/cm3.
    • The uppermost solid part of the mantle and the entire crust constitute the Lithosphere.
    • The asthenosphere (in between 80-200km) is a highly viscous, mechanically weak and ductile, deforming region of the upper mantle which lies just below the lithosphere.
    • The asthenosphere is the main source of magma and it is the layer over which the lithospheric plates/ continental plates move (plate tectonics).
    • The discontinuity between the upper mantle and the lower mantleis known as Repetti Discontinuity.
    • The portion of the mantle which is just below the lithosphere and asthenosphere, but above the core is called as Mesosphere.

    [C] Core

    • It is the innermost layer surrounding the earth’s centre.
    • The core is separated from the mantle by Guttenberg’s Discontinuity.
    • It is composed mainly of iron (Fe) and nickel (Ni) and hence it is also called as NIFE.
    • It constitutes nearly 15% of earth’s volume and 32.5% of earth’s mass.
    • It is the densest layer of the earth with its density ranges between 9.5-14.5g/cm3.
    • It spins independently because it floats in the liquid metal outer core. One cycle of the swing is about seven decades approximately.
    • It consists of two sub-layers: the inner core and the outer core.
    • The inner core is in solid state and the outer core is in the liquid state (or semi-liquid).
    • The discontinuity between the upper core and the lower core is called as Lehmann Discontinuity.
    • Barysphere is sometimes used to refer the core of the earth or sometimes the whole interior.

    What should one understand about the interior of the earth?

    • It is not possible to know about the earth’s interior by direct observations because of the huge size and the changing nature of its interior composition.
    • It is an almost impossible distance for the humans to reach till the centre of the earth (The earth’s radius is 6,370 km).
    • The rapid increase in temperature below the earth’s surface is mainly responsible for setting a limit to direct observations inside the earth.

    Sources of Information about the interior of the earth

    Direct Sources:

    1. Rocks from mining area
    2. Volcanic eruptions

    Indirect Sources

    1. By analyzing the rate of change of temperature and pressurefrom the surface towards the interior.
    2. Meteors, as they belong to the same type of materials earth is made of.
    3. Gravitation, which is greater near poles and less at the equator.
    4. Gravity anomaly, which is the change in gravity value according to the mass of material, gives us information about the materials in the earth’s interior.
    5. Magnetic sources.
    6. Seismic Waves: the shadow zones of body waves (Primary and secondary waves) give us information about the state of materials in the interior.

    What is the new study about?

    • Exactly how the inner core rotates has been a matter of debate between scientists— and the latest research is expected to prove controversial.
    • A new research has analyzed seismic waves from repeating earthquakes over the last six decades.
    • It shows that- the inner core started rotating slightly faster than the rest of the planet in the early 1970s, the study said.
    • But it had been slowing down before coming in sync with Earth’s rotation around 2009.

    What made the core spin slower?

    • So far there is little to indicate that what the inner core does has many effects on surface dwellers.
    • The researchers said this rotation timeline roughly lines up with changes in what is called the “length of day”— small variations in the exact time it takes Earth to rotate on its axis.
    • But the researchers said they believed there were physical links between all of Earth’s layers, from the inner core to the surface.

     

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  • What is Winter Solstice?

    solstice

    Today, December 21, is Winter Solstice, the shortest day of the year in the Northern Hemisphere. In the Southern Hemisphere, conversely, it was Summer Solstice, the year’s longest day.

    What is Winter Solstice?

    • The winter solstice, also called the hibernal solstice, occurs when either of Earth’s poles reaches its maximum tilt away from the Sun.
    • This happens twice yearly, once in each hemisphere.

    What are Solstices?

    • Solstices occur because Earth’s axis of rotation is tilted about 23.4 degrees relative to Earth’s orbit around the sun.
    • This tilt drives our planet’s seasons, as the Northern and Southern Hemispheres get unequal amounts of sunlight over the course of a year.
    • From March to September, the Northern Hemisphere is tilted more toward the sun, driving its spring and summer.
    • From September to March, the Northern Hemisphere is tilted away, so it feels like autumn and winter.
    • The Southern Hemisphere’s seasons are reversed.
    • On two moments each year—what are called solstices—Earth’s axis is tilted most closely toward the sun.

    Impact on day-time

    • The hemisphere tilted most toward our home star sees its longest day, while the hemisphere tilted away from the sun sees its longest night.
    • During the Northern Hemisphere’s summer solstice—which always falls around June 21—the Southern Hemisphere gets its winter solstice.
    • Likewise, during the Northern Hemisphere’s winter solstice—which always falls around December 22—the Southern Hemisphere gets its summer solstice.

    Impact of the tilted axis

    • The Northern Hemisphere spends half the year tilted in the direction of the Sun, getting direct sunlight during long summer days.
    • During the other half of the year, it tilts away from the Sun, and the days are shorter.
    • Winter Solstice, December 21, is the day when the North Pole is most tilted away from the Sun.
    • The tilt is also responsible for the different seasons that we see on Earth.
    • The side facing the Sun experiences day, which changes to night as Earth continues to spin on its axis.

    Un-impacted regions

    • On the Equator, day and night are equal. The closer one moves towards the poles, the more extreme the variation.
    • During summer in either hemisphere, that pole is tilted towards the Sun and the polar region receives 24 hours of daylight for months.
    • Likewise, during winter, the region is in total darkness for months.

    Celebrations associated with the Winter Solstice

    • For centuries, this day has had a special place in several communities due to its astronomical significance and is celebrated in many ways across the world.
    • Jewish people call the Winter Solstice ‘Tekufat Tevet’, which marks the start of winter.
    • Ancient Egyptians celebrated the birth of Horus, the son of Isis (divine mother goddess) for 12 days during mid-winter.
    • In China, the day is celebrated by families coming together for a special meal.
    • In the Persian region, it is celebrated as Yalda or Shab-e-Yalda. The festival marks the last day of the Persian month of Azar and is seen as the victory of light over darkness.
    • Families celebrate Yalda late into the night with special foods such as ajeel nuts, pomegranates and watermelon, and recite works of the 14th-century Sufi poet Hafiz Shirazi.

    In Vedic tradition

    • In Vedic tradition, the northern movement of the Earth on the celestial sphere is implicitly acknowledged in the Surya Siddhanta.
    • It outlines the Uttarayana (the period between Makar Sankranti and Karka Sankranti). Hence, Winter Solstice is the first day of Uttarayana.

     

    Try this MCQ:

    Q. On 21st June, the Sun

    (a) Does not set below the horizon at the Arctic Circle

    (b) Does not set below the horizon at Antarctic Circle

    (c) Shines vertically overhead at noon on the Equator

    (d) Shines vertically overhead at the Tropic of Capricorn

     

    [wpdiscuz-feedback id=”g83sek2y9c” question=”Please leave a feedback on this” opened=”1″]Post your answers here.[/wpdiscuz-feedback]

     

     

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  • Cyclone Mandous makes landfall in Tamil Nadu

    mandous

    Cyclone Mandous crossed the north Tamil Nadu coast with fierce winds and heavy downpour.

    Cyclone Mandous

    • ‘Mandous’ was a name submitted by WMO member United Arab Emirates and is pronounced as ‘Man-Dous.’
    • It means ‘treasure box’ in Arabic.

    What are Tropical Cyclones?

    • A tropical cyclone is an intense circular storm that originates over warm tropical oceans and is characterized by low atmospheric pressure, high winds, and heavy rain.
    • Cyclones are formed over slightly warm ocean waters. The temperature of the top layer of the sea, up to a depth of about 60 meters, need to be at least 28°C to support the formation of a cyclone.
    • This explains why the April-May and October-December periods are conducive for cyclones.
    • Then, the low level of air above the waters needs to have an ‘anticlockwise’ rotation (in the northern hemisphere; clockwise in the southern hemisphere).
    • During these periods, there is an ITCZ in the Bay of Bengal whose southern boundary experiences winds from west to east, while the northern boundary has winds flowing east to west.
    • Once formed, cyclones in this area usually move northwest. As it travels over the sea, the cyclone gathers more moist air from the warm sea which adds to its heft.

    Requirements for a Cyclone to form

    There are six main requirements for tropical cyclogenesis:

    • Sufficiently warm sea surface temperatures
    • Atmospheric instability
    • High humidity in the lower to middle levels of the troposphere
    • Enough Coriolis force to develop a low-pressure centre
    • A pre-existing low-level focus or disturbance
    • Low vertical wind shear

    How are the cyclones named?

    • In 2000, a group of nations called WMO/ESCAP (World Meteorological Organisation/United Nations Economic and Social Commission for Asia and the Pacific) decided to name cyclones.
    • It comprised Bangladesh, India, the Maldives, Myanmar, Oman, Pakistan, Sri Lanka and Thailand, decided to start naming cyclones in the region.
    • After each country sent in suggestions, the WMO/ESCAP Panel on Tropical Cyclones (PTC) finalized the list.
    • The WMO/ESCAP expanded to include five more countries in 2018 — Iran, Qatar, Saudi Arabia, United Arab Emirates and Yemen.

    Basics

    Cyclones

    • The atmospheric disturbances which involve a closed circulation of air around a low pressure at the center and high pressure at the periphery, rotating anti-clockwise in the northern hemisphere and clockwise in the southern hemisphere (due to the Coriolis force) are called “cyclones”.

    Cyclones are broadly classified into two types based on the latitudes of their origin-

    • Tropical cyclones
    • Temperate/Extra-tropical cyclones

    Tropical Cyclones

    • Tropical cyclones develop in the region between the tropics of Capricorn and Cancer. These are violent storms that originate over oceans in tropical areas and move on to the coastal regions bringing large-scale destruction caused by violent winds, very heavy rainfall and storm surges. These cyclones are one of the most devastating natural calamities.
    • Tropical cyclones mostly move along with the direction of trade winds, so they travel from east to west and make landfall on the eastern coasts of the continents.
    • Tropical cyclones are known by different names depending on the regions of the world. They are known as Hurricanes in the Atlantic, Typhoons in the Western Pacific and South China Sea, Willy-willies in Western Australia and Cyclones in the Indian Ocean.

    Temperate Cyclones/Extra-Tropical Cyclones

    • It occurs between 30°-60° latitude in both hemispheres (in between the Tropic of Cancer and the Arctic circle in the northern hemisphere and in between the Tropic of Capricorn and the Antarctic Circle in the southern hemisphere).
    • These cyclones move with the westerlies and are therefore oriented from west to east.

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  • Mauna Loa: Hawaii’s biggest Volcano set to erupt

    mauna

    Mauna Loa, the world’s largest active volcano has erupted after 38 years, spewing ash and debris, and covering the sky of Hawaii’s Big Island.

    Where is Mauna Loa?

    mauna

    • Mauna Loa is one of five volcanoes that together make up the Big Island of Hawaii (biggest being the Mauna Kea).
    • It is the southernmost island in the Hawaiian archipelago.
    • It’s not the tallest (that title goes to) but it’s the largest and makes up about half of the island’s land mass.
    • It sits immediately north of Kilauea volcano, which is currently erupting from its summit crater.

    Do you know?

    Any volcano that has erupted within the Holocene period (in the last 11,650 years) is considered to be “active” by scientists. “Dormant” volcanoes are those active volcanoes which are not in the process of erupting currently, but have the potential to do so in the future.

    Why do volcanoes erupt?

    • The deeper one goes under the surface of the Earth towards its core, the hotter it gets.
    • The geothermal gradient, the amount that the Earth’s temperature increases with depth, indicates heat flowing from the Earth’s warm interior to its surface.
    • At a certain depth, the heat is such that it melts rocks and creates what geologists call ‘magma’.
    • Magma is lighter than solid rock and hence it rises, collecting in magma chambers.
    • Chambers that have the potential to cause volcanic eruptions are found at a relatively shallow depth, between six to ten km under the surface.
    • As magma builds up in these chambers, it forces its way up through cracks and fissures in Earth’s crust. This is what we call a volcanic eruption.
    • The magma that surfaces on the Earth’s crust is referred to as lava.

    Why is the eruption of Mauna Loa so explosive?

    • Eruptions vary in intensity and explosiveness, depending on the composition of the magma.
    • In simple terms, runny magma makes for less explosive volcanic eruptions that typically are less dangerous.
    • Since the magma is runny, gasses are able to escape, leading to a steady but relatively gentle flow of lava out of the mouth of the volcano.
    • The eruption at Mauna Loa is of this kind. Since the lava flows out at a slow pace, people typically have enough time to move out of the way
    • . Geologists are also able to predict the flow of the lava depending on the incline and exact consistency it has.

    How is vulcanism measured?

    • The Volcanic Explosivity Index (VEI) is a scale used to measure the explosivity of a volcano.
    • It has a range of 1 to 8 with a higher VEI indicating more explosivity.
    • While the VEI of the current eruption at Mauna Loa is not known yet, the previous eruption in 1984 was deemed to have a VEI of 0.

     

    Also read about the Pacific Ring of Fire.

     

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  • Places in news: Shiveluch Volcano

    shiveluch

    The Shiveluch volcano on the Kamchatka Peninsula in the Russian Far East has increased its activity and is now in danger of erupting violently.

    About Shiveluch

    • Shiveluch is one of the largest and most active volcanoes in Kamchatka, having erupted at least 60 times in the past 10,000 years.
    • Kamchatka is home to 29 active volcanoes, part of a vast belt of Earth known as the “Ring of Fire” which circles the Pacific Ocean and is prone to eruptions and frequent earthquakes.
    • It has two main parts: Old Shiveluch, which tops 3,283 metres (10,771 ft), and Young Shiveluch – a smaller, 2,800-metre peak protruding from its side.
    • Young Shiveluch lies within an ancient caldera – a large crater-like basin that likely formed when the older part underwent a catastrophic eruption at least 10,000 years ago.
    • It is this part that has become extremely active; the lava dome continues to grow and that stronger “fumarole activity” has been observed.

     

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