Here are the key points to cover in your 10 minute presentation:
- Clearly define the landform/concept you are presenting
- Provide a real world example to illustrate your point
- Explain how the landform is formed by tectonic processes
- Describe the characteristic features and appearance
- Discuss any environmental or geological impacts/hazards
- Use clear diagrams and images to support your explanations
- Leave time for questions
Grade 8 Integrated Science Chapter 15 Lesson 2 on volcanoes. This lesson goes into detail about volcanoes, plate boundaries, lava chemistry, eruption types, and volcano types. The purpose of this lesson is for students to understand where and why volcanoes form and what factors cause differing volcanic features.
Grade 8 Integrated Science Chapter 15 Lesson 2 on volcanoes. This lesson goes into detail about volcanoes, plate boundaries, lava chemistry, eruption types, and volcano types. The purpose of this lesson is for students to understand where and why volcanoes form and what factors cause differing volcanic features.
A PowerPoint Presentation for Grade 9 teachers. This presentation is ONLY suggested guide for teachers to assist them on the discussion after the activities as suggested in the Learner's Module were performed. Please feel free to add comments and suggestions. Thanks!
(Yes, a parody of dumb ways to die). Key geography notes I made for a homework task - covering key volcanic hazards as part of tectonics, including examples and case studies.
what are Volcanism and volcano,
Distribution of Volcanoes
Kinds of Volcanoes
Types of Volcanic Hazards
Preparing for Volcanic Emergencies
A volcano is generally a conical shaped hill or mountain built by accumulations of lava flows, tephra, and volcanic ash. About 95% of active volcanoes occur at the plate subduction zones and at the mid-oceanic ridges. The other 5% occur in areas associated with lithospheric hot spots. These hot spots have no direct relationships with areas of crustal creation or subduction zones. It is believed that hot spots are caused by plumes of rising magma that have their origin within the asthenosphere.
Over the last 2 million years, volcanoes have been depositing lava, tephra, and ash in particular areas of the globe. These areas occur at hot spots, rift zones, and along plate boundaries where tectonic subduction is taking place within the asthenosphere.
The most prevalent kinds of volcanoes on the Earth's surface are the kind which form the "Pacific Rim of Fire". Those are volcanoes which form as a result of subduction of the nearby lithosphere.
A PowerPoint Presentation for Grade 9 teachers. This presentation is ONLY suggested guide for teachers to assist them on the discussion after the activities as suggested in the Learner's Module were performed. Please feel free to add comments and suggestions. Thanks!
(Yes, a parody of dumb ways to die). Key geography notes I made for a homework task - covering key volcanic hazards as part of tectonics, including examples and case studies.
what are Volcanism and volcano,
Distribution of Volcanoes
Kinds of Volcanoes
Types of Volcanic Hazards
Preparing for Volcanic Emergencies
A volcano is generally a conical shaped hill or mountain built by accumulations of lava flows, tephra, and volcanic ash. About 95% of active volcanoes occur at the plate subduction zones and at the mid-oceanic ridges. The other 5% occur in areas associated with lithospheric hot spots. These hot spots have no direct relationships with areas of crustal creation or subduction zones. It is believed that hot spots are caused by plumes of rising magma that have their origin within the asthenosphere.
Over the last 2 million years, volcanoes have been depositing lava, tephra, and ash in particular areas of the globe. These areas occur at hot spots, rift zones, and along plate boundaries where tectonic subduction is taking place within the asthenosphere.
The most prevalent kinds of volcanoes on the Earth's surface are the kind which form the "Pacific Rim of Fire". Those are volcanoes which form as a result of subduction of the nearby lithosphere.
I made this presentation for my school project after that I thought that I should upload it on any slide so I uploaded this to help others in making presentations and getting ideas.It is a class 7 project.
Volcanoes , What Causes Volcanoes , Volcanic Landforms: Extrusive & Intrusive Volcanic Landforms , Distribution of Volcanoes around the Globe
, Effects of Volcanism , Reasons for Concentration of volcanoes along the Ring of Fire .
A volcano is an opening in the Earth’s crust that allows molten rock, gases and debris to escape to the surface.
During a volcanic eruption, lava and other debris can flow at speeds of up to 100 mph, destroying everything in their path.
Different magma types behave differently as lava flows, depending on their temperature, viscosity, and gas content.
Magmas that are generated deep within the Earth begin to rise because they are less dense than the surrounding solid rocks.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
How to Make a Field invisible in Odoo 17Celine George
It is possible to hide or invisible some fields in odoo. Commonly using “invisible” attribute in the field definition to invisible the fields. This slide will show how to make a field invisible in odoo 17.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Introduction to AI for Nonprofits with Tapp NetworkTechSoup
Dive into the world of AI! Experts Jon Hill and Tareq Monaur will guide you through AI's role in enhancing nonprofit websites and basic marketing strategies, making it easy to understand and apply.
Synthetic Fiber Construction in lab .pptxPavel ( NSTU)
Synthetic fiber production is a fascinating and complex field that blends chemistry, engineering, and environmental science. By understanding these aspects, students can gain a comprehensive view of synthetic fiber production, its impact on society and the environment, and the potential for future innovations. Synthetic fibers play a crucial role in modern society, impacting various aspects of daily life, industry, and the environment. ynthetic fibers are integral to modern life, offering a range of benefits from cost-effectiveness and versatility to innovative applications and performance characteristics. While they pose environmental challenges, ongoing research and development aim to create more sustainable and eco-friendly alternatives. Understanding the importance of synthetic fibers helps in appreciating their role in the economy, industry, and daily life, while also emphasizing the need for sustainable practices and innovation.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Biological screening of herbal drugs: Introduction and Need for
Phyto-Pharmacological Screening, New Strategies for evaluating
Natural Products, In vitro evaluation techniques for Antioxidants, Antimicrobial and Anticancer drugs. In vivo evaluation techniques
for Anti-inflammatory, Antiulcer, Anticancer, Wound healing, Antidiabetic, Hepatoprotective, Cardio protective, Diuretics and
Antifertility, Toxicity studies as per OECD guidelines
2. Learning Objectives
• Look at the various aspects of extrusive
igneous activity
• formation of volcanic cones and fissures
• The formation of Lava plateaux
3. What is extrusive igneous
activity?
• In simple terms extrusive igneous activity
refers to when magma reaches the surface
of the earth and becomes known as lava.
• The lava flows once cooled form landforms
such as volcanoes
4. 3 Forms of activity
• Major extrusive activity can come as a gas, liquid or solid:
• Gas - sulphur, hydrogen, carbon dioxide and hot
steam(geysers).: When uprising magma decreases in pressure
suddenly, gases within magma explode to the earth's surface
and cause destruction.
• Solid - pyroclast: Mainly composed of: fragments of country-
rock, solidified lava and fine materials of volcanic ash and dust. It
can be classified in term of size into volcanic bombs, volcanic
blocks, lapilli, volcanic ash and volcanic dust.
• Liquid – lava, hot springs.
5. Extrusive Landforms
• There are several types of extrusive landforms
whose nature depends on how gaseous or
viscous the lava is when it reaches the earth’s
surface.
• Lava produced by the upward movement of
material from the mantle is Basaltic and tends
to be located along mid-ocean ridges, over hot
spots and along rift valleys.
6. • Lava that results from the process of subduction is described
as andesitic (after the Andes) and occurs as island arcs or at
destructive plate boundaries where oceanic crust is
destroyed.
8. Volcano Classification
• There is no universally accepted method of
classification. The two most quoted groupings
are:
- According to shape
- Nature of the eruption.
10. Fissure Eruptions
• When two plates move apart lava may be ejected
through fissures rather than a central vent.
• The Heimaey eruption of 1973 in Iceland began
with a fissure of over 3km.
• This is small compared to Laki also in Iceland in
1783 where a fissure exceeding 30km in length
opened up.
• The basalt may form a large plateaux, filling
hollows rather than building up into a typical cone-
shaped volcanic peak.
• The columnar jointing produced by the slow
cooling of the lava provides tourist attractions e.g.
Giant’s Causeway
11. Basic or shield volcanoes such as Mauna Loa
in Hawaii have lava flowing out of a central
vent and can spread over a wide area before
solidifying. The result is a cone with long
gentle sides made up of many layers of lava
from repeated flows.
Acid or dome volcanoes – acid lava quickly
solidifies in the air and this produces a steep
sided, convex cone as most lava builds up
near to the vent. In the case of Mt Pelee the
lava actually solidified as it came up the vent
and produced a spine rather than flowing
down the sides.
12. Ash and cinder cones (e.g. Paricutin) form when
ash and cinders building up into a symmetrical
cone with a larger crater.
Composite cones – many of the larger, classically
shaped volcanoes result from alternating types
of eruption in which first ash and then lava
(usually acidic) is ejected. Mt Etna is a result of a
series of both violent and more gentle eruptions.
13. Calderas - when the build up of gases
becomes extreme, huge explosions may
clear the magma chamber beneath the
volcano and remove the summit of the
cone. This causes the sides of the crater
to subside, thus widening the opening to
several kilometres in diameter. In the case
of both Thira and Krakatoa, the enlarged
crater or caldera has been flooded by the
sea and within the resultant lagoons, later
eruptions have formed smaller cones.
14. Minor Extrusive Landforms
Minor extrusive landforms are often associated with, but not
exclusive to, areas of declining volcanic activity. They include
soltfatara, fumaroles, geysers and mud volcanoes.
15. The Nature of Eruptions
• Icelandic - lava flows gently from the
fissure, usually on flat slopes
• there is no central crater.
• Giant cracks open in the ground and expel
vast quantities of lava that spread far and
wide to form huge pools that can cover
almost everything around.
• When these pools of lava cool and
solidify, the surface remains mostly flat.
• Since the source cracks are usually
buried, there is often nothing "volcano-like"
to see--only a flat plain.
•
16. Hawaiian type (VEI 0-1)
• there is a small vent through which small amount
• fluid basaltic lava is thrown into the air in jets from a vent or
line of vents (a fissure) at the summit or on the flank of a
volcano.
• The jets can last for hours or even days, a phenomenon
known as fire fountaining.
• The spatter created by bits of hot lava falling out of the
fountain can melt together and form lava flows, or build hills
called spatter cones.
• Lava flows may also come from vents at the same time as
fountaining occurs, or during periods where fountaining has
paused.
17. Hawaiian type
• Because these flows are very fluid, they can travel miles
from their source before they cool and harden.
• Hawaiian eruptions get their names from the Kilauea
volcano on the Big Island of Hawaii, which is famous for
producing spectacular fire fountains.
• Two excellent examples of these are the 1969-1974
Mauna Ulu eruption on the volcano’s flank, and the 1959
eruption of the Kilauea Iki Crater at the summit of
Kilauea.
• In both of these eruptions, lava fountains reached heights
of well over a thousand feet
19. Strombolian type (VEI 1-2)
• These are distinct bursts of fluid lava (usually basalt or
basaltic andesite) from the mouth of a magma-filled
summit conduit.
• The explosions usually occur every few minutes at regular
or irregular intervals.
• The explosions of lava, which can reach heights of
hundreds of meters, are caused by the bursting of large
bubbles of gas, which travel upward in the magma-filled
conduit until they reach the open air.
20. Strombolian type
• This kind of eruption can create a
variety of forms of eruptive products:
• Spatter, or hardened globs of glassy
lava.
• Scoria, which are hardened chunks of
bubbly lava; lava bombs, or chunks of
lava a few cm to a few m in size; ash
• Small lava flows (which form when hot
spatter melts together and flows
downslope).
• Products of an explosive eruption are
often collectively called tephra.
21. Strombolian type
• Strombolian eruptions are often associated with
small lava lakes, which can build up in the
conduits of volcanoes.
• They are one of the least violent of the
explosive eruptions, although they can still be
very dangerous if bombs or lava flows reach
inhabited areas.
• Strombolian eruptions are named for the
volcano that makes up the Italian island of
Stromboli, which has several erupting summit
vents.
• These eruptions are particularly spectacular at
night, when the lava glows brightly
22. Vulcanian type (VEI 2-3)
• A Vulcanian eruption is a short, violent, relatively small
explosion of viscous magma (usually andesite, dacite, or
rhyolite).
• This type of eruption results from the fragmentation and
explosion of a plug of lava in a volcanic conduit, or from
the rupture of a lava dome (viscous lava that piles up
over a vent).
• Vulcanian eruptions create powerful explosions in which
material can travel faster than 350 meters per second
(800 mph) and rise several kilometres into the air.
• They produce tephra, ash clouds, and pyroclastic
density currents (clouds of hot ash, gas and rock that
flow almost like fluids).
23. Vulcanian type
• Vulcanian eruptions may be repetitive and
go on for days, months, or years, or they
may precede even larger explosive
eruptions.
• They are named for the Italian island of
Vulcano, where a small volcano that
experienced this type of explosive eruption
was thought to be the vent above the forge
of the Roman smith god Vulcan.
24. Vesuvian type
• Typified by the eruption of Mount Vesuvius
in Italy in A.D. 79, great quantities of ash-
laden gas are violently discharged to form
cauliflower-shaped cloud high above the
volcano
• It has a long period of inactivity but right
after it erupts with enormous power
25. Peléan eruption (VEI 3-4)
• They can occur when viscous magma, typically of rhyolitic
or andesitic type, is involved, and share some similarities
with Vulcanian eruptions.
• The most important characteristics of a Peléan eruption is
the presence of a glowing avalanche of hot volcanic ash, a
pyroclastic flow.
• Formation of lava domes is another characteristic feature.
Short flows of ash or creation of pumice cones may be
observed as well.
• The initial phases of eruption are characterized by
pyroclastic flows.
26. Peléan eruption
• The tephra deposits have lower volume and
range than the corresponding Plinian and
Vulcanian eruptions.
• The viscous magma then forms a steep-
sided dome or volcanic spine in the
volcano's vent.
• The dome may later collapse, resulting in
flows of ash and hot blocks. The eruption
cycle is usually completed in few years, but
in some cases may continue for decades.
• The 1902 explosion of Mount Pelée is the
first described case of a Peléan
eruption, and gave it its name.
27. Krakatoan or Plinian (VEI 4-8)
• They are caused by the fragmentation of gassy magma, and are
usually associated with very viscous magmas (dacite and rhyolite).
• They release enormous amounts of energy and create eruption
columns of gas and ash that can rise up to 50 km (35 miles) high at
speeds of hundreds of meters per second.
• Ash from an eruption column can drift or be blown hundreds or
thousands of miles away from the volcano.
• The eruption columns are usually shaped like a mushroom (similar to
a nuclear explosion) or an Italian pine tree; Pliny the Younger, a
Roman historian, made the comparison while viewing the 79 AD
eruption of Mount Vesuvius, and Plinian eruptions are named for him.
28. Point of Note
• Vesuvian and Plinian are often to referred to as one and the
same but differentiations are made within certain textbooks
• Plinian eruptions are extremely destructive, and can
even obliterate the entire top of a mountain, as occurred
at Mount St. Helens in 1980.
• They can produce falls of ash, scoria and lava bombs
miles from the volcano, and pyroclastic density currents
that raze forests, strip soil from bedrock and obliterate
anything in their paths.
• These eruptions are often climactic, and a volcano with
a magma chamber emptied by a large Plinian eruption
may subsequently enter a period of inactivity.
29. Eruptions and the VEI
• VEI was proposed in 1982 as a way to describe the
relative size or magnitude of explosive volcanic
eruptions.
• It is a 0-to-8 index of increasing explosivity. Each
increase in number represents an increase around a
factor of ten.
• The VEI uses several factors to assign a number,
including volume of erupted pyroclastic material (for
example, ashfall, pyroclastic flows, and other ejecta),
height of eruption column, duration in hours, and
qualitative descriptive terms
30. Eruptions and the VEI
The classification of the eruption shows some similarity to the Volcano Explosivity Index
(VEI) developed in the USA.
32. •In the figure, the volumes of several
past explosive eruptions and the
corresponding VEI are shown.
• Numbers in parentheses represent
total volume of erupted pyroclastic
material (tephra, volcanic ash, and
pyroclastic flows) for selected
eruptions; the volumes are for
uncompacted deposits.
• Each step increase represents a ten
fold increase in the volume of erupted
pyroclastic material.
33. What Determines Eruption Type?
• The crystal and gas content and temperature of a magma
help determine a volcano’s eruption style.
• Crystals in magma make it more viscous, so magma with a
high crystal content is more likely to explode than flow.
• Gases create explosions if they cannot easily escape from
viscous magma, but they can also be released without
explosions (or with only minor ones) from fluid magma.
• High-temperature magmas usually erupt effusively, while
low-temperature magmas cannot flow easily and are more
likely to erupt explosively.
34. Lava Domes
• Are mounds that form when viscous lava is erupted slowly
and piles up over the vent, rather than moving away as a
lava flow.
• The sides of most domes are very steep and typically are
mantled with unstable rock debris formed during or shortly
after dome emplacement.
• Most domes are composed of silica-rich lava which may
contain enough pressurized gas to cause explosions
during dome extrusion.
36. Your task
In pairs you have to choose one of the two most devastating
eruptions of the last 100,000 years:
- Mount Tambora 1815 VEI 7
-Mount Toba 73,000 BP (Before Present 1950) VEI 8
You must then put together a short presentation covering the
following key areas:
- Location (geographical and geological)
-Type of volcano (fissure, composite cone etc.)
- Events leading to the eruption
- Effects of the eruption (immediate, short-term, long-term) at a
number of different scales – local, regional, global.
37. TASKS
• Students are to separate into groups of three and
research the effects earthquakes can have on the
landscape and give a presentation on one of the following:
– Rift Valleys
– Ground Displacement
– Dip slips and Strike Slip
– Definition and Example of S and P waves
– Normal Fault, Reverse Fault, Oblique-slip fault
– Block Mountains or Horst
– Fault Scarps
– Fold Landforms – Anticline, Recumbent Fold, Fold Mountains