Earthquakes occur along faults when built-up elastic stress is suddenly released. Sensitive instruments around the world record seismic waves from earthquakes, which are used to determine the focus and epicenter. The epicenter is the point on the surface directly above the focus. Magnitude scales such as the Richter scale are used to measure earthquake size based on wave amplitude. Structural damage from earthquakes depends on factors like ground shaking intensity and the nature of the material buildings are constructed on. Seismographs can also detect other seismic events like explosions, which seismologists use to investigate events like alleged nuclear tests.
8th Grade Integrated Science Chapter 5 Lesson 1 on Earthquakes. This lesson covers a broad range of information including types of faults, earthquake distribution, types of seismic waves, the difference between focus and epicenter, as well as mapping Earth's interior. There is a section that introduces how to locate an epicenter. Additional labs have been added for practice. Finally the lesson ends with different scales including the Richter magnitude scale, the moment magnitude scale, and the Modified Mercalli scale.
8th Grade Integrated Science Chapter 5 Lesson 1 on Earthquakes. This lesson covers a broad range of information including types of faults, earthquake distribution, types of seismic waves, the difference between focus and epicenter, as well as mapping Earth's interior. There is a section that introduces how to locate an epicenter. Additional labs have been added for practice. Finally the lesson ends with different scales including the Richter magnitude scale, the moment magnitude scale, and the Modified Mercalli scale.
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.
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.
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.
Ethnobotany and Ethnopharmacology:
Ethnobotany in herbal drug evaluation,
Impact of Ethnobotany in traditional medicine,
New development in herbals,
Bio-prospecting tools for drug discovery,
Role of Ethnopharmacology in drug evaluation,
Reverse Pharmacology.
Instructions for Submissions thorugh G- Classroom.pptxJheel Barad
This presentation provides a briefing on how to upload submissions and documents in Google Classroom. It was prepared as part of an orientation for new Sainik School in-service teacher trainees. As a training officer, my goal is to ensure that you are comfortable and proficient with this essential tool for managing assignments and fostering student engagement.
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.
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 Indian economy is classified into different sectors to simplify the analysis and understanding of economic activities. For Class 10, it's essential to grasp the sectors of the Indian economy, understand their characteristics, and recognize their importance. This guide will provide detailed notes on the Sectors of the Indian Economy Class 10, using specific long-tail keywords to enhance comprehension.
For more information, visit-www.vavaclasses.com
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
2. What is an earthquake ?
• An earthquake is the vibration of Earth
produced by the rapid release of energy
• Energy released radiates in all directions
from its source, the focus
• Energy is in the form of waves
• Sensitive instruments around the world
record the event
4. What is an earthquake
• Earthquakes and faults
• Movements that produce earthquakes are
usually associated with large fractures in
Earth’s crust called faults
• Most of the motion along faults can be
explained by the plate tectonics theory
5. What is an earthquake
• Elastic rebound
• Mechanism for earthquakes was first
explained by H.F. Reid
– Rocks on both sides of an existing fault are
deformed by tectonic forces
– Rocks bend and store elastic energy
– Frictional resistance holding the rocks
together is overcome
6. What is an earthquake ?
• Elastic rebound
• Earthquake mechanism
– Slippage at the weakest
point (the focus) occurs
– Vibrations (earthquakes)
occur as the deformed
rock “springs back” to its
original shape (elastic
rebound)
• Earthquakes most often
occur along existing faults
whenever the frictional
forces on the fault
surfaces are overcome
7. San Andreas: An active
earthquake zone
• San Andreas is the most
studied fault system in the
world
• Displacement occurs along
discrete segments 100 to 200
kilometres long
• Some portions exhibit slow,
gradual displacement known
as fault creep
• Other segments regularly slip
producing small earthquakes
8. San Andreas: An active
earthquake zone
• Displacements along the San
Andreas fault
• Still other segments store elastic
energy for hundreds of years
before rupturing in great
earthquakes
– Process described as stick-slip motion
– Great earthquakes should occur
about every 50 to 200 years along
these sections
10. Seismology
• Seismographs are instruments that
record seismic waves
• Records the movement of Earth in
relation to a stationary mass on a rotating
drum or magnetic tape
12. Seismology
• Seismographs
• More than one type of seismograph is
needed to record both vertical and
horizontal ground motion
• Types of seismic waves
• Surface waves
• Body waves
13. Seismology
• Types of seismic waves
• Surface waves
– Travel along outer part of Earth
– Complex motion
– Cause greatest destruction
– referred to as long waves, or L waves
14. Seismology
• Types of seismic waves
• Body Waves (Primary and Secondary)
– Primary (P) waves
» Push-pull (compress and expand) motion,
changing the volume of the intervening material
» Travel through solids, liquids, and gases
– Secondary (S) waves
» Shake" motion at right angles to their direction of
travel
» Travel only through solids
15. Seismology
• Types of seismic waves
• Body waves
– Secondary (S) waves
» Slower velocity than P waves
» Slightly greater amplitude than P waves
16. Locating the source of earthquakes
• Terms
• Focus - the place within Earth where
earthquake waves originate
• Epicenter – location on the surface
directly above the focus
• Epicenter is located using the difference
in velocities of P and S waves
17. Locating the source of earthquakes
• Locating the epicenter of an earthquake
• Three station recordings are needed to
locate an epicenter
• Each station determines the time interval
between the arrival of the first P wave and
the first S wave at their location
• A travel-time graph is used to determine
each station’s distance to the epicenter
19. Locating the source of earthquakes
• Locating the epicenter of an earthquake
• A circle with a radius equal to the distance
to the epicenter is drawn around each
station
• The point where all three circles intersect
is the earthquake epicenter
21. Locating the source of earthquakes
• Earthquake belts
• About 95 percent of the energy released
by earthquakes originates in a few
relatively narrow zones that wind around
the globe
• Major earthquake zones include the
Circum-Pacific belt, Mediterranean Sea
region to the Himalayan complex, and the
oceanic ridge system
23. Locating the source of earthquakes
• Earthquake depths
• Definite patterns exist
– Shallow focus occur along the oceanic ridge
system
– Almost all deep-focus earthquakes occur in
the circum-Pacific belt, particularly in
regions situated landward of deep-ocean
trenches
25. Measuring the size of earthquakes
• Two measurements that describe the size
of an earthquake are
• Intensity – a measure of the degree of
earthquake shaking at a given locale
based on the amount of damage
• Magnitude – estimates the amount of
energy released at the source of the
earthquake
26. Measuring the size of earthquakes
• Magnitude scales
• Richter magnitude - concept introduced
by Charles Richter in 1935
• Richter scale
– Based on the amplitude of the largest seismic
wave recorded
– Accounts for the decrease in wave amplitude
with increased distance
27. Measuring the size of earthquakes
• Magnitude scales
• Richter scale
– Largest magnitude recorded on a Wood-
Anderson seismograph was 8.9 (earthquake
in Chile, 1960 –
– Magnitudes less than 2.0 are not felt by
humans
– Each unit of Richter magnitude increase
corresponds to a tenfold increase in wave
amplitude and a 32-fold energy increase
28.
29. Earthquake destruction
• Amount of structural damage
attributable to earthquake vibrations
depends on
• Intensity and duration of the vibrations
• Nature of the material upon which the
structure rests
• Design of the structure
30. Earthquake destruction
• Destruction from seismic vibrations
• Ground shaking
– Regions within 20 to 50 kilometers of the
epicenter will experience about the same
intensity of ground shaking
– However, destruction varies considerably
mainly due to the nature of the ground on
which the structures are built
32. Earthquake destruction
• Destruction from seismic vibrations
• Basic Shaking
-degree of damage partly depends on
severity of earthquake and integrity of
material (e.g. buildings on igneous rocks
sustain less damage than on loose
sediments)
33. Earthquake destruction
• Liquefaction of the ground
– Unconsolidated materials saturated with
water turn into a mobile fluid
– Characterization of material upon which
buildings are constructed can make or break
an insurance claim
(Damage due to earthquake-induced
liquefaction, or faulty construction ?
Differences in effect can be more subtle than
one might think).
- relevant also to building contractors (can be
sued for knowingly building on high-risk
ground)
34. Effects of liquefaction
Buildings built on poorly consolidated sediment
-tilted due to sediment liquefaction resulting from earthquake
35. An accident long-waiting to happen
Subdivision at Point Fermin, California
-shore undercut by waves, poorly consolidated material highly unstable
-add seismic activity, and you’re toast !
36. Forensics on a Global Scale
Seismographs not only tell us when and where
an earthquake occurred.
Other vibrations can also be recorded:
Rockfalls (if close enough to recording station),
Mine and Quarry Blasts,
Nuclear Explosions
37. Geophysicists can use seismograph records to
subtantiate or dispel reported events that could
produce significant vibrations
Similar to the way voices of different
people differ in acoustic characteristics,
so do different seismic events (seismic
fingerprints).
38. For example, nuclear test events
can be detected
Significant nuclear test sites: 1945-1998
39. Comparison of signatures of nuclear test
explosion and an earthquake
Primary Secondary Surface Waves
Nuclear test recorded at international monitoring station in
Pakistan, May 11, 1998, about 740 km from blast
40. Example:
Alleged nuclear testing in Iraq in 1989
Alleged test was reported to have been carried in the
vicinity of Lake Rezazza, approximately 100 km
southwest of Baghdad at 10:30 am on 19 September,
1989
Terry Wallace (University of Arizona), examined the
global seismicity catalogues produced by the
International Seismic Center and the US Geological
Survey.
No seismic disturbances at all were detected in Iraq that
day
41. Significantly, no seismicity within 50 km of the reported
test site was apparent for the years 1980 to 1999 !
Problem: some asserted that the lower limit of
detection for global catalogues was magnitude 4.0,
so it was possible that a smaller magnitude event
might have not been picked up by the sensors.
However, seismicity catalogues for Israel, Jordan and
Iran (well within range of detection) reported no
seismic event in the region on that date either (19
September 1989).
Verdict: allegation of Iraqi nuclear testing was false
42. Another Example:
Sinking of Russian Sub
12th August 2000, it was reported
that a Russian submarine (the
Kursk) sank north of Kola
Peninsula (Barents Sea).
On same date, two explosions
were detected on seismic
records, with gap of two minutes
between explosions (the second
event being much bigger)
Comparison of results from different
seismograph revealed that the
second explosion was the
equivalent of five tonnes of TNT
exploding (within the range
expected for detonation of a
nuclear warhead)
43. Other events detected from
seismograph records
1. Sinking of USS Scorpion submarine
near the mid-Atlantic ridge in 1968
2. Sinking of another Russian sub in the
Baltic in 1989.
3. Sinking of a large oil derrick in the
North Sea (produced a 3.5-magnitude
quake when it hit the ocean floor)