TopicTopicSeismic waves Seismic waves

their their typestypes& & Seismicity of PakistanSeismicity of Pakistan

Prepared by Prepared by

Azhar MahmoodAzhar Mahmood

Seismic Waves Seismic Waves

Seismic waves are the waves of energy Seismic waves are the waves of energy that travel through the earth layers, and that travel through the earth layers, and

are a result of an earthquake, explosion or are a result of an earthquake, explosion or a volcanism.a volcanism.

Seismic waves are studied by Seismic waves are studied by geophysicist called seismologist and these geophysicist called seismologist and these waves are recorded by a seismometer waves are recorded by a seismometer hydrophone in water, or accelerometer.hydrophone in water, or accelerometer.

The propagation The propagation velocityvelocity of the waves depends  of the waves depends on on densitydensity and  and elasticityelasticity of the medium.  of the medium. Velocity tends to increase with depth, and Velocity tends to increase with depth, and ranges from approximately 2 to 8 km/s in the ranges from approximately 2 to 8 km/s in the Earth's Earth's crustcrust up to 13 km/s in the deep  up to 13 km/s in the deep mantlemantle. .

Earthquakes create distinct types of waves with Earthquakes create distinct types of waves with different velocities; when reaching seismic different velocities; when reaching seismic observatories, their different observatories, their different travel timetravel time help  help scientists to locate the source of the scientists to locate the source of the earthquake earthquake hypocenterhypocenter..

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Diagram of waveDiagram of wave

  In geophysics the refraction or reflection In geophysics the refraction or reflection of seismic waves is used for of seismic waves is used for researchresearch into  into the structure of the Earth's interior, and the structure of the Earth's interior, and man made vibrations are often generated man made vibrations are often generated to investigate shallow, subsurface to investigate shallow, subsurface structures. structures.

1. 1. Body WavesBody Waves Primary WavesPrimary Waves Secondary WavesSecondary Waves

2. 2. Surface WavesSurface Waves Rayleigh WavesRayleigh Waves Love WavesLove Waves

Types of seismic wavesTypes of seismic waves

Traveling through the interior of the Traveling through the interior of the earth, earth, body wavesbody waves  arrive before the  arrive before the surface waves emitted by an earthquake. surface waves emitted by an earthquake. These waves are of a higherThese waves are of a higher frequency than surface waves. frequency than surface waves.

Body WavesBody Waves

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Body wavesBody waves

Primary WavesPrimary Waves The first kind of body wave is the The first kind of body wave is the P P

wavewave  or  or primary waveprimary wave . This is the . This is the fastest kind of seismic wave, and, fastest kind of seismic wave, and, consequently, the first to 'arrive' at a consequently, the first to 'arrive' at a seismic station. The P wave can move seismic station. The P wave can move through solid rock and fluids, like water or through solid rock and fluids, like water or the liquid layers of the earth.the liquid layers of the earth.

It pushes and pulls the rock it moves It pushes and pulls the rock it moves through just like sound waves push and through just like sound waves push and pull the air.pull the air.

P waves are also known P waves are also known as as compressional wavescompressional waves , because of , because of the pushing and pulling they do. the pushing and pulling they do.

Secondary WavesSecondary Waves The second type of body wave is the The second type of body wave is the S S

wavewave  or  or secondary wavesecondary wave , which is the , which is the second wave you feel in an earthquake. second wave you feel in an earthquake.

An S wave is slower than a P wave and An S wave is slower than a P wave and can only move through solid rock, not can only move through solid rock, not through any liquid medium. It is this through any liquid medium. It is this property of S waves that led seismologists property of S waves that led seismologists to conclude that the Earth's to conclude that the Earth's outer coreouter core  is  is a liquid.a liquid.

Surface WavesSurface Waves Travelling only through the crust, Travelling only through the crust, surface surface

waveswaves  are of a lower frequency than  are of a lower frequency than body waves, and are easily distinguished body waves, and are easily distinguished on a seismogram as a result. on a seismogram as a result. 

Though they arrive after body waves, it is Though they arrive after body waves, it is surface waves that are almost enitrely surface waves that are almost enitrely responsible for the damage and responsible for the damage and destruction associated with earthquakes. destruction associated with earthquakes.

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Surface wavesSurface waves

Love WavesLove Waves The first kind of surface wave is called The first kind of surface wave is called

a a Love waveLove wave , named after A.E.H. Love, , named after A.E.H. Love, a British mathematician.a British mathematician.

      It's the fastest surface wave and moves It's the fastest surface wave and moves the ground from side-to-side. Confined to the ground from side-to-side. Confined to the surface of the crust, Love waves the surface of the crust, Love waves produce entirely horizontal motion.produce entirely horizontal motion.

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DiagramDiagram

Rayleigh WavesRayleigh Waves The other kind of surface wave is The other kind of surface wave is

the the Rayleigh waveRayleigh wave , named for John , named for John William Strutt, Lord Rayleigh William Strutt, Lord Rayleigh

  A Rayleigh wave rolls along the ground A Rayleigh wave rolls along the ground just like a wave rolls across a lake or an just like a wave rolls across a lake or an ocean. Because it rolls, it moves the ocean. Because it rolls, it moves the ground up and down, and side-to-side in ground up and down, and side-to-side in the same direction that the wave is the same direction that the wave is moving. moving.

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DiagramDiagram

Most of the shaking felt from an Most of the shaking felt from an earthquake is due to the Rayleigh wave, earthquake is due to the Rayleigh wave, which can be much larger than the other which can be much larger than the other waves.waves.

On the basis of seismic waves we On the basis of seismic waves we differentiate different layers of earthdifferentiate different layers of earth

On the basis of seismic waves we sub On the basis of seismic waves we sub classified the layers.classified the layers.

FaisalFaisal 2020

Uses of seismic wavesUses of seismic waves

Use in the identification of hydrocarbons Use in the identification of hydrocarbons reservoirs.reservoirs.

Oil and gas exploration.Oil and gas exploration.

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Uses;Uses;

SEISMICITY OF PAKISTANSEISMICITY OF PAKISTAN Pakistan is an earthquake prone country. A Pakistan is an earthquake prone country. A number of earthquakes have hit Pakistan number of earthquakes have hit Pakistan resulting in losses of life and property. resulting in losses of life and property. Pakistan Meteorological Department (PMD) Pakistan Meteorological Department (PMD) presently has a network of eleven seismic presently has a network of eleven seismic stations. By using recorded data the stations. By using recorded data the seismicity and zoning maps of Pakistanseismicity and zoning maps of Pakistan

From our experiences derived from the From our experiences derived from the recent October 8, 2005, Kashmir earthquake recent October 8, 2005, Kashmir earthquake it emphasized the importance of redefining it emphasized the importance of redefining the seismic zonation for whole Pakistan the seismic zonation for whole Pakistan especially seismically active areas to especially seismically active areas to minimize further losses of human lives and minimize further losses of human lives and failure of infrastructure due to such failure of infrastructure due to such earthquakesearthquakes

Geographical and Tectonic location of Geographical and Tectonic location of PakistanPakistanPakistan is situated in South Asian region Pakistan is situated in South Asian region between longitudes 61º & 76º E and latitudes between longitudes 61º & 76º E and latitudes 24º & 37º N covering a total land area of 24º & 37º N covering a total land area of 796,095 sq. km. The country shares its 796,095 sq. km. The country shares its borders with Iran to the West, India in the borders with Iran to the West, India in the Southeast, Afghanistan in the Northwest, and Southeast, Afghanistan in the Northwest, and China in the North. China in the North. Figure 1Figure 1 shows, the shows, the Geographical location of Pakistan in South Geographical location of Pakistan in South Asia. Asia.

Seismic Zones of PakistanSeismic Zones of PakistanSeismic zoning map of Pakistan have been Seismic zoning map of Pakistan have been developed by Pakistan Meteorological developed by Pakistan Meteorological Department in 1998 by earthquake data collected Department in 1998 by earthquake data collected from United States of Geological Survey (USGS), from United States of Geological Survey (USGS), International Seismological Centre (ISC) and International Seismological Centre (ISC) and PMD for the period from 1905 to 1998.PMD for the period from 1905 to 1998.

Seismicity of PakistanSeismicity of Pakistan

The seismicity of Pakistan concern with The seismicity of Pakistan concern with the series of EARTHQUAKES damaging the series of EARTHQUAKES damaging different areas of Pakistan at huge extent.different areas of Pakistan at huge extent.

Two major earthquakes are Two major earthquakes are 1: Earthquake of 20051: Earthquake of 2005 2: Earthquake of 20082: Earthquake of 2008 3: Earthquake of 20133: Earthquake of 2013

Earthquake of 8 oct,2005Earthquake of 8 oct,2005

Use in the identification of hydrocarbons Use in the identification of hydrocarbons reservoirs.reservoirs.

Oil and gas exploration.Oil and gas exploration.

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Location MapLocation Map

The M 7.6 quake on Oct. 8, 2005, The M 7.6 quake on Oct. 8, 2005, kil led about 80,000 people in kil led about 80,000 people in northwestern Pakistan and Kashmir northwestern Pakistan and Kashmir and left more than 3 mill ion and left more than 3 mill ion homelesshomeless

THE SEVERITY OF THE THE SEVERITY OF THE 2005 KASHMIR EARTHQUAKE2005 KASHMIR EARTHQUAKE DISASTER DISASTER WAS RELATED TO ITS WAS RELATED TO ITS MAGNITUDE, SHALLOW DEPTH, MAGNITUDE, SHALLOW DEPTH, SOIL AMPLIFICATION, AND POOR SOIL AMPLIFICATION, AND POOR CONSTRUCTION CONSTRUCTION

KASHMIR EARTHQUAKEKASHMIR EARTHQUAKE

8:50 AM8:50 AM OCTOBER 8, 2005 OCTOBER 8, 2005 M 7.6M 7.6 10 KM (6 MI) 10 KM (6 MI) DEPTHDEPTH 79,000 DEAD IN PAKISTAN; 1,400 79,000 DEAD IN PAKISTAN; 1,400

IN INDIAIN INDIA COLLAPSED COLLAPSED SCHOOLS AND SCHOOLS AND

HOSPITALSHOSPITALS 3 MILLION 3 MILLION HOMELESSHOMELESS

OCTOBER 8, 2005 PAKISTAN OCTOBER 8, 2005 PAKISTAN EARTHQUAKEEARTHQUAKE

OCCURRENCEOCCURRENCE

The earthquake occurred in the The earthquake occurred in the Main Boundary Thrust Zone Main Boundary Thrust Zone (MBTZ), which runs along the (MBTZ), which runs along the Himalayan Arc for about 2,500 km.Himalayan Arc for about 2,500 km.

The epicenter was near The epicenter was near MuzaffarabadMuzaffarabad , the capital of , the capital of Pakistani administered KashmirPakistani administered Kashmir

MUZARAFFABADMUZARAFFABAD

MUZAFFARABAD MUZAFFARABAD (LANDSLIDE)(LANDSLIDE)

Earthquake of 24 sep,2013Earthquake of 24 sep,2013

4:29 PM, SEPT. 24, 20134:29 PM, SEPT. 24, 2013

At At 4:29 pm local t ime4:29 pm local t ime , a dangerous , a dangerous time of the day, a magnitude-7.7 time of the day, a magnitude-7.7 earthquake occurred at a earthquake occurred at a SHALLOW SHALLOW depth of 23 km in a depth of 23 km in a seismically active area 63 km (36 seismically active area 63 km (36 miles) from the city of miles) from the city of Awaran, Awaran, located in Pakistan’s Balochistan located in Pakistan’s Balochistan Province.Province.

TECTONIC SETTINGTECTONIC SETTING

According to the US Geological According to the US Geological Survey, the earthquake, which had Survey, the earthquake, which had a relatively shallow depth, was a relatively shallow depth, was centered at a centered at a complex triple complex triple junction in the Earth’s subsurface junction in the Earth’s subsurface where the Arabian tectonic plate is where the Arabian tectonic plate is pushing its way beneath the pushing its way beneath the Eurasian plate as the Indian plate is Eurasian plate as the Indian plate is ramming both of them from the ramming both of them from the south:south:

A COMPLEX TECTONIC A COMPLEX TECTONIC SETTINGSETTING

UNIQUE HAPPENING: UNIQUE HAPPENING: THE QUAKE’S THE QUAKE’S

TECTONICS CREATED TECTONICS CREATED AN ISLANDAN ISLAND

ISLAND CREATED ISLAND CREATED DURING THE QUAKEDURING THE QUAKE

ISLAND: EARTHQUAKE ISLAND: EARTHQUAKE OR VOLCANO RELATED? OR VOLCANO RELATED?

NEW ISLAND EMMITING NEW ISLAND EMMITING POISONOUS GASPOISONOUS GAS

The new island, now The new island, now extending 20 m (60-70 feet) extending 20 m (60-70 feet) above the water, began above the water, began emitt ing poisonous methane emitt ing poisonous methane gas on September 26.gas on September 26.

EARLY REPORTS OF EARLY REPORTS OF DEATHSDEATHS

Early reportsEarly reports indicate that indicate that at least at least 350 people died350 people died and and 450 were 450 were injured injured as the result of collapses of as the result of collapses of mud brick houses and poorly mud brick houses and poorly constructed buildings. constructed buildings.

90 present of Anwaran destroyed.90 present of Anwaran destroyed.

Earthquake of 29 Earthquake of 29 oct,2008oct,2008

2008 PAKISTAN 2008 PAKISTAN EARTHQUAKEEARTHQUAKE

2008 PAKISTAN 2008 PAKISTAN EARTHQUAKEEARTHQUAKE

The earthquake struck near Quetta, The earthquake struck near Quetta, the capital of Baluchistan Province.the capital of Baluchistan Province.

QuettaQuetta, hit by a devastating , hit by a devastating earthquake earthquake in 1935in 1935, is located in a , is located in a known fault zone caused by known fault zone caused by ongoing collision of the Indo-ongoing collision of the Indo-Australian and Eurasian plates.Australian and Eurasian plates.

2008 PAKISTAN 2008 PAKISTAN EARTHQUAKEEARTHQUAKE

ZiaratZiarat, located in the hills and , located in the hills and one of one of the poorest areas of Pakistanthe poorest areas of Pakistan, was , was devastated by devastated by landslides and landslides and collapse of mud brick housescollapse of mud brick houses..

Early estimates indicate that as Early estimates indicate that as many as many as 12,000 are now homeless 12,000 are now homeless in 40 degree weatherin 40 degree weather. .

The The 2008 Pakistan earthquake2008 Pakistan earthquake  was a  was a magnitude M6.4 earthquake that hit the magnitude M6.4 earthquake that hit the

Pakistani province of Balochistan on October Pakistani province of Balochistan on October 29, 2008. The US Geological 29, 2008. The US Geological

Survey reported that the quake occurred Survey reported that the quake occurred 60 km north of Quetta and 185 km southeast 60 km north of Quetta and 185 km southeast of the Afghanistan city of Kandahar at 04:09 of the Afghanistan city of Kandahar at 04:09

local time (28 October, 23:09 UTC) at a local time (28 October, 23:09 UTC) at a depth of 15 km at 30.653°N, 67.323°E.depth of 15 km at 30.653°N, 67.323°E. More More

than 200 were injured and 120,000 were than 200 were injured and 120,000 were homeless homeless

LONG-TERM RECOVERY LONG-TERM RECOVERY NEEDS AFTER EARTHQUAKE NEEDS AFTER EARTHQUAKE

DISASTERDISASTER NEEDNEED: 2 TO 3 MILLION NEW : 2 TO 3 MILLION NEW

DWELLINGS THAT ARE EARTHQUAKE DWELLINGS THAT ARE EARTHQUAKE RESILIENT.RESILIENT.

NEEDNEED:: NEW SCHOOLS THAT ARE NEW SCHOOLS THAT ARE EARTHQUAKE RESILIENT.EARTHQUAKE RESILIENT.

NEEDNEED:: NEW HOSPITALS THAT ARE NEW HOSPITALS THAT ARE EARTHQUAKE RESILIENT. EARTHQUAKE RESILIENT.

NEEDNEED:: INFRASTRUCTURE THAT IS INFRASTRUCTURE THAT IS EARTHQUAKE RESILIENT(Public Health EARTHQUAKE RESILIENT(Public Health for example).for example).

28 December 1974, at 12:11 28 December 1974, at 12:11 UTC35°06′N 72°54′E6.2UTC35°06′N 72°54′E6.2

5300 deaths, 17000 injured 5300 deaths, 17000 injured Hunza, Hazara and Swat districtHunza, Hazara and Swat district North-West Frontier Province  North-West Frontier Province

Named as Named as 1974 Hunza 1974 Hunza earthquakeearthquake

31 May 1935 at 3:02am 28° 31 May 1935 at 3:02am 28° 52′0″N 66°23′0″E, 7.7M, 30,000 52′0″N 66°23′0″E, 7.7M, 30,000 deaths , 60000 injured Location deaths , 60000 injured Location

Ali Jaan, Balochistan and Ali Jaan, Balochistan and Named as Named as 1935 Balochistan 1935 Balochistan

earthquakeearthquake

Precautionary Measures for Precautionary Measures for Disasters.Disasters.

STARTING POINTS STARTING POINTS

IN-COUNTRY IN-COUNTRY BASIC AND BASIC AND APPLIED APPLIED RESEARCHRESEARCH

IMPLEMENTATION IMPLEMENTATION OF LESSONS OF LESSONS FROM FROM DISASTERSDISASTERS

GROUND GROUND SHAKING MAPSSHAKING MAPS

BUILDING CODESBUILDING CODES EDUCATIONAL EDUCATIONAL

SURGES AND SURGES AND TRAINING FOR TRAINING FOR COMMUNITY COMMUNITY PROFESSIONALSPROFESSIONALS

STEPS TOWARDS STEPS TOWARDS EARTHQUAKE RESILIENCEEARTHQUAKE RESILIENCE

CONTINUOUS PUBLIC CONTINUOUS PUBLIC AWARENESS AWARENESS PROGRAMSPROGRAMS

EDUCATIONAL EDUCATIONAL SURGES AND SURGES AND TRAINING FOR TRAINING FOR PROFESSIONALSPROFESSIONALS

EXPANDED SEISMIC EXPANDED SEISMIC AND BUILDING AND BUILDING MONITORING MONITORING SYSTEMSSYSTEMS

EXPANDED EXPANDED COMMUNICATION COMMUNICATION SYSTEMSSYSTEMS

MODERN BUILDING MODERN BUILDING CODES FOR NEW CODES FOR NEW BUILDINGSBUILDINGS

MODERN STANDARDS MODERN STANDARDS FOR NEW FOR NEW INFRASTRUCTUREINFRASTRUCTURE

STRENGTHENING AND STRENGTHENING AND RETROFIT FOR RETROFIT FOR EXISTING EXISTING STRUCTURESSTRUCTURES

EXPANDED HEALTH-EXPANDED HEALTH-CARE SYSTEMSCARE SYSTEMS

LONG-TERM NEEDS OF PAKISTANLONG-TERM NEEDS OF PAKISTAN

NEED:NEED: 2 TO 3 MILLION NEW 2 TO 3 MILLION NEW DWELLINGS THAT ARE DWELLINGS THAT ARE EARTHQUAKE RESILIENT.EARTHQUAKE RESILIENT.

NEED:NEED: NEW SCHOOLS THAT ARE NEW SCHOOLS THAT ARE EARTHQUAKE RESILIENT.EARTHQUAKE RESILIENT.

NEED:NEED: NEW HOSPITALS THAT NEW HOSPITALS THAT ARE EARTHQUAKE RESILIENT. ARE EARTHQUAKE RESILIENT.

NEED:NEED: NEW INFRASTRUCTURE NEW INFRASTRUCTURE THAT IS EARTHQUAKE THAT IS EARTHQUAKE RESILIENT.RESILIENT.

THE END-GAME OF AN EDUCATIONAL SURGE

UNDER-STAND

UNDER-STAND

IDENT-IFY

IDENT-IFY

HEARHEAR

PERSON-ALIZE

PERSON-ALIZE

APPLI-CATIONSAPPLI-

CATIONS

PERIOD OF PERIOD OF INTEGRATIONINTEGRATION

WINDOW OF WINDOW OF OPPORTUNITYOPPORTUNITY

PERIOD OF PERIOD OF IMPLEMENTAIMPLEMENTA

TIONTION