This document provides an overview of seismotectonics and its importance in understanding earthquake hazards. It defines seismotectonics as the relationship between earthquakes, active tectonics and faults in a region. Seismotectonic maps and zonation are used to identify active faults and determine zones of similar seismic potential. Together with information on regional tectonics, historical seismicity, and stress fields, seismotectonics allows scientists to assess earthquake hazards by identifying capable faults. The document outlines these concepts and techniques and provides examples of seismotectonic analysis in Pakistan.
It covers seismic method, gravity method, electromagnetic method, magnetic method and radiometric method. all these methods help in mineral exploration
Boundary problems between :-
Precambrian/Cambrian
Permian/Triassic
Cretaceous/Tertiary
Neogene/Quaternary
Stratigraphic boundaries are determined by one or more of geological events such as volcanic activity, sedimentation, tectonism, paleo-environments & evolution of life.
Faunal records have played major role in determining the boundaries of the Phanerozoic units.
The other geological events are dated on the evidence of fossil records.
Metallogenic Epoch and Province
Metallogenetic Epochs
Metallogenetic epochs, as defined above, are specific periods characterised by formation of large number of mineral deposits. It does not mean that all the mineral deposits formed during a definite metallogenetic epochs. In India the chief metallogenetic epochs were:
1. Precambrian
2. Late Palaeozoic
3. Late Mesozoic to Early Tertiary
Groundwater province is an area or region in which geology and climate combine to produce groundwater conditions consistent enough to permit useful generalisations.
It covers seismic method, gravity method, electromagnetic method, magnetic method and radiometric method. all these methods help in mineral exploration
Boundary problems between :-
Precambrian/Cambrian
Permian/Triassic
Cretaceous/Tertiary
Neogene/Quaternary
Stratigraphic boundaries are determined by one or more of geological events such as volcanic activity, sedimentation, tectonism, paleo-environments & evolution of life.
Faunal records have played major role in determining the boundaries of the Phanerozoic units.
The other geological events are dated on the evidence of fossil records.
Metallogenic Epoch and Province
Metallogenetic Epochs
Metallogenetic epochs, as defined above, are specific periods characterised by formation of large number of mineral deposits. It does not mean that all the mineral deposits formed during a definite metallogenetic epochs. In India the chief metallogenetic epochs were:
1. Precambrian
2. Late Palaeozoic
3. Late Mesozoic to Early Tertiary
Groundwater province is an area or region in which geology and climate combine to produce groundwater conditions consistent enough to permit useful generalisations.
The current ppt discusses the different types of lineations formed due to deformation.
Lineations are genetically related to the foliation planes on which they occur, particularly where both are shaped by mineral orientations. Therefore, the planar and linear fabrics are both together aspects of the same three-dimensional geometry, which is related to the shape of the finite strain ellipsoid or,
more important still, to the history of incremental strains.
Seismic Refraction Test
Subsurface investigation by seismic refraction
Seismic Data Analysis
Seismic refraction instrumental set up and operation
P-waves velocity ranges for different strata
Sedimentary basins are the depressions in the earth's crust where loose particles accumulate and finally lithified to form sedimentary rocks. Basins are particularly attractive to geoscientists from time immemorial due to the wealth hidden here in the form of oil, gas, coal etc. In this document you will find the types of basins, basin-fill types, methods of basin analysis and so on.
The presentation comprises the Gravity Method, It's anomaly, reduction, and its applications. The Gravity method is commonly used in Geology specifically in Geophysics.
THE PRESENCE AND VARIETY OF A PARTICULAR PLANTS
SPECIES IN THE AREA OF MINERALISATION HAVE BEEN RECOGNISED AS A GUIDE TO LOCATING ORE, METHOD,UNIVERSAL INDICATORS , UNIVERSAL INDICATOR ,LOCAL INDICATOR
Earthquake and its predictions. by engr. ghulam yasin taunsviShan Khan
Earthquakes occur where tectonic plates meet, called faults.
California lies on one of the most active faults in the world, the San Andreas Fault.
Methods for predicting earthquakes on these faults vary, none of them being 100% accurate.
Predictions are generally given for a time frame instead of an exact date
The current ppt discusses the different types of lineations formed due to deformation.
Lineations are genetically related to the foliation planes on which they occur, particularly where both are shaped by mineral orientations. Therefore, the planar and linear fabrics are both together aspects of the same three-dimensional geometry, which is related to the shape of the finite strain ellipsoid or,
more important still, to the history of incremental strains.
Seismic Refraction Test
Subsurface investigation by seismic refraction
Seismic Data Analysis
Seismic refraction instrumental set up and operation
P-waves velocity ranges for different strata
Sedimentary basins are the depressions in the earth's crust where loose particles accumulate and finally lithified to form sedimentary rocks. Basins are particularly attractive to geoscientists from time immemorial due to the wealth hidden here in the form of oil, gas, coal etc. In this document you will find the types of basins, basin-fill types, methods of basin analysis and so on.
The presentation comprises the Gravity Method, It's anomaly, reduction, and its applications. The Gravity method is commonly used in Geology specifically in Geophysics.
THE PRESENCE AND VARIETY OF A PARTICULAR PLANTS
SPECIES IN THE AREA OF MINERALISATION HAVE BEEN RECOGNISED AS A GUIDE TO LOCATING ORE, METHOD,UNIVERSAL INDICATORS , UNIVERSAL INDICATOR ,LOCAL INDICATOR
Earthquake and its predictions. by engr. ghulam yasin taunsviShan Khan
Earthquakes occur where tectonic plates meet, called faults.
California lies on one of the most active faults in the world, the San Andreas Fault.
Methods for predicting earthquakes on these faults vary, none of them being 100% accurate.
Predictions are generally given for a time frame instead of an exact date
RUNING HEAD THE CONTINENTAL DRIFT THEORY1THE CONTINENTAL DR.docxjoellemurphey
RUNING HEAD: THE CONTINENTAL DRIFT THEORY
1
THE CONTINENTAL DRIFT THEORY 2
The Continental Drift Theory
Benjamin Bogan
SCI101-1303B-11: Introduction to the Sciences
9/16/13
The Continental Drift Theory
The continental drift theory was developed by a German scientist, Alfred Wegener. In his book, The Origin of Continents and Oceans, he argued that the continental landmasses were drifting across the earth. He based this on the fact that the coast of Western Africa and South America looked like the edges of interlocking pieces of a jigsaw puzzle. He was thus convinced that the two were once part of an enormous single landmass known as Pangaea before it split apart. This was supported by geological and biological similarities in these areas. The development of this theory spearheaded a lot of research since many scientists did not agree with the idea. It led to more developments in the mid and late 20th century that proved that the landmasses were in constant motion. The additions on the Wegener’s evidence include paleomagnetism and seafloor spreading.
Paleomagnetism is the study of the intensity and orientation of the Earth’s magnetic field as preserved in the magnetic orientation of certain minerals present in rocks. Many scientists have explored this field to find evidence of continental drift. When hot magma rises and cools on the surface of the Earth, the minerals present become magnetized in alignment with the Earth’s magnetic field. Rocks formed at different places on the Earth’s surface have different magnetizations. Some rocks have magnetizations that do not agree with their position on the Earth but this is due to the wandering of the Earth’s magnetic poles. Using the alignment of magnetic minerals in the rock layers, the movement of the magnetic poles could be traced through the different geologic periods. The record of direction and intensity of magnetic field kept by certain minerals in rocks provide information on the past behavior of Earth’s magnetic field and the past location of tectonic plates. This is therefore an evidence of landmasses drifting. The magnetized minerals also show the direction to the Earth’s magnetic poles and provide a means of determining their latitude of origin. Polar wandering, which is the apparent movement of the magnetic poles illustrated in rocks, indicates that continents have moved. This is shown in polar wandering curves. The curves for North America and Europe have similar shapes but are separated by about 240 of longitude. The difference between the paths can be reconciled if the continents are placed next to one another.
In 1962, Harry Hess, a geologist and an army commander during the World War II, added a geologic mechanism to account for Wegener’s moving continents. During his work to determine the deepest part of the sea, he discovered hundreds of flat-topped mountains that shaped the floor of the Pacif ...
Probabilistic seismic hazard assessment in the vicinity of MBT and MCT in wes...inventy
Research Inventy : International Journal of Engineering and Science is published by the group of young academic and industrial researchers with 12 Issues per year. It is an online as well as print version open access journal that provides rapid publication (monthly) of articles in all areas of the subject such as: civil, mechanical, chemical, electronic and computer engineering as well as production and information technology. The Journal welcomes the submission of manuscripts that meet the general criteria of significance and scientific excellence. Papers will be published by rapid process within 20 days after acceptance and peer review process takes only 7 days. All articles published in Research Inventy will be peer-reviewed.
Earth Expansion Tectonics - The New Paradigm (Part 4)Proyecto Matriz
“Que cese su guerra de todos contra todos y que en lugar de esto se unan en la conquista
de las rocas. Que el ser humano, en lugar de ir en busca del oro, en busca de fama
o malgastando su fuerza productiva en labores infructíferas, escoja la mejor parte:
la cooperación pacífica en la investigación y el descubrimiento del rumbo de las fuerzas
naturales con el fin de desarrollar productos nutritivos, y el apacible deleite
de las frutas que la tierra puede producir en abundancia para todos..”
JULIUS HENSEL (1892)
Shear wave velocity and Geology Based Seismic Microzonation of Port-au-Prince...Johana Sharmin
This is a presentation entirely based on the paper published by Brady R. Cox and his team. I just focused on the key points of the paper in the presentation.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
Earliest Galaxies in the JADES Origins Field: Luminosity Function and Cosmic ...Sérgio Sacani
We characterize the earliest galaxy population in the JADES Origins Field (JOF), the deepest
imaging field observed with JWST. We make use of the ancillary Hubble optical images (5 filters
spanning 0.4−0.9µm) and novel JWST images with 14 filters spanning 0.8−5µm, including 7 mediumband filters, and reaching total exposure times of up to 46 hours per filter. We combine all our data
at > 2.3µm to construct an ultradeep image, reaching as deep as ≈ 31.4 AB mag in the stack and
30.3-31.0 AB mag (5σ, r = 0.1” circular aperture) in individual filters. We measure photometric
redshifts and use robust selection criteria to identify a sample of eight galaxy candidates at redshifts
z = 11.5 − 15. These objects show compact half-light radii of R1/2 ∼ 50 − 200pc, stellar masses of
M⋆ ∼ 107−108M⊙, and star-formation rates of SFR ∼ 0.1−1 M⊙ yr−1
. Our search finds no candidates
at 15 < z < 20, placing upper limits at these redshifts. We develop a forward modeling approach to
infer the properties of the evolving luminosity function without binning in redshift or luminosity that
marginalizes over the photometric redshift uncertainty of our candidate galaxies and incorporates the
impact of non-detections. We find a z = 12 luminosity function in good agreement with prior results,
and that the luminosity function normalization and UV luminosity density decline by a factor of ∼ 2.5
from z = 12 to z = 14. We discuss the possible implications of our results in the context of theoretical
models for evolution of the dark matter halo mass function.
(May 29th, 2024) Advancements in Intravital Microscopy- Insights for Preclini...Scintica Instrumentation
Intravital microscopy (IVM) is a powerful tool utilized to study cellular behavior over time and space in vivo. Much of our understanding of cell biology has been accomplished using various in vitro and ex vivo methods; however, these studies do not necessarily reflect the natural dynamics of biological processes. Unlike traditional cell culture or fixed tissue imaging, IVM allows for the ultra-fast high-resolution imaging of cellular processes over time and space and were studied in its natural environment. Real-time visualization of biological processes in the context of an intact organism helps maintain physiological relevance and provide insights into the progression of disease, response to treatments or developmental processes.
In this webinar we give an overview of advanced applications of the IVM system in preclinical research. IVIM technology is a provider of all-in-one intravital microscopy systems and solutions optimized for in vivo imaging of live animal models at sub-micron resolution. The system’s unique features and user-friendly software enables researchers to probe fast dynamic biological processes such as immune cell tracking, cell-cell interaction as well as vascularization and tumor metastasis with exceptional detail. This webinar will also give an overview of IVM being utilized in drug development, offering a view into the intricate interaction between drugs/nanoparticles and tissues in vivo and allows for the evaluation of therapeutic intervention in a variety of tissues and organs. This interdisciplinary collaboration continues to drive the advancements of novel therapeutic strategies.
Introduction:
RNA interference (RNAi) or Post-Transcriptional Gene Silencing (PTGS) is an important biological process for modulating eukaryotic gene expression.
It is highly conserved process of posttranscriptional gene silencing by which double stranded RNA (dsRNA) causes sequence-specific degradation of mRNA sequences.
dsRNA-induced gene silencing (RNAi) is reported in a wide range of eukaryotes ranging from worms, insects, mammals and plants.
This process mediates resistance to both endogenous parasitic and exogenous pathogenic nucleic acids, and regulates the expression of protein-coding genes.
What are small ncRNAs?
micro RNA (miRNA)
short interfering RNA (siRNA)
Properties of small non-coding RNA:
Involved in silencing mRNA transcripts.
Called “small” because they are usually only about 21-24 nucleotides long.
Synthesized by first cutting up longer precursor sequences (like the 61nt one that Lee discovered).
Silence an mRNA by base pairing with some sequence on the mRNA.
Discovery of siRNA?
The first small RNA:
In 1993 Rosalind Lee (Victor Ambros lab) was studying a non- coding gene in C. elegans, lin-4, that was involved in silencing of another gene, lin-14, at the appropriate time in the
development of the worm C. elegans.
Two small transcripts of lin-4 (22nt and 61nt) were found to be complementary to a sequence in the 3' UTR of lin-14.
Because lin-4 encoded no protein, she deduced that it must be these transcripts that are causing the silencing by RNA-RNA interactions.
Types of RNAi ( non coding RNA)
MiRNA
Length (23-25 nt)
Trans acting
Binds with target MRNA in mismatch
Translation inhibition
Si RNA
Length 21 nt.
Cis acting
Bind with target Mrna in perfect complementary sequence
Piwi-RNA
Length ; 25 to 36 nt.
Expressed in Germ Cells
Regulates trnasposomes activity
MECHANISM OF RNAI:
First the double-stranded RNA teams up with a protein complex named Dicer, which cuts the long RNA into short pieces.
Then another protein complex called RISC (RNA-induced silencing complex) discards one of the two RNA strands.
The RISC-docked, single-stranded RNA then pairs with the homologous mRNA and destroys it.
THE RISC COMPLEX:
RISC is large(>500kD) RNA multi- protein Binding complex which triggers MRNA degradation in response to MRNA
Unwinding of double stranded Si RNA by ATP independent Helicase
Active component of RISC is Ago proteins( ENDONUCLEASE) which cleave target MRNA.
DICER: endonuclease (RNase Family III)
Argonaute: Central Component of the RNA-Induced Silencing Complex (RISC)
One strand of the dsRNA produced by Dicer is retained in the RISC complex in association with Argonaute
ARGONAUTE PROTEIN :
1.PAZ(PIWI/Argonaute/ Zwille)- Recognition of target MRNA
2.PIWI (p-element induced wimpy Testis)- breaks Phosphodiester bond of mRNA.)RNAse H activity.
MiRNA:
The Double-stranded RNAs are naturally produced in eukaryotic cells during development, and they have a key role in regulating gene expression .
Cancer cell metabolism: special Reference to Lactate PathwayAADYARAJPANDEY1
Normal Cell Metabolism:
Cellular respiration describes the series of steps that cells use to break down sugar and other chemicals to get the energy we need to function.
Energy is stored in the bonds of glucose and when glucose is broken down, much of that energy is released.
Cell utilize energy in the form of ATP.
The first step of respiration is called glycolysis. In a series of steps, glycolysis breaks glucose into two smaller molecules - a chemical called pyruvate. A small amount of ATP is formed during this process.
Most healthy cells continue the breakdown in a second process, called the Kreb's cycle. The Kreb's cycle allows cells to “burn” the pyruvates made in glycolysis to get more ATP.
The last step in the breakdown of glucose is called oxidative phosphorylation (Ox-Phos).
It takes place in specialized cell structures called mitochondria. This process produces a large amount of ATP. Importantly, cells need oxygen to complete oxidative phosphorylation.
If a cell completes only glycolysis, only 2 molecules of ATP are made per glucose. However, if the cell completes the entire respiration process (glycolysis - Kreb's - oxidative phosphorylation), about 36 molecules of ATP are created, giving it much more energy to use.
IN CANCER CELL:
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
Unlike healthy cells that "burn" the entire molecule of sugar to capture a large amount of energy as ATP, cancer cells are wasteful.
Cancer cells only partially break down sugar molecules. They overuse the first step of respiration, glycolysis. They frequently do not complete the second step, oxidative phosphorylation.
This results in only 2 molecules of ATP per each glucose molecule instead of the 36 or so ATPs healthy cells gain. As a result, cancer cells need to use a lot more sugar molecules to get enough energy to survive.
introduction to WARBERG PHENOMENA:
WARBURG EFFECT Usually, cancer cells are highly glycolytic (glucose addiction) and take up more glucose than do normal cells from outside.
Otto Heinrich Warburg (; 8 October 1883 – 1 August 1970) In 1931 was awarded the Nobel Prize in Physiology for his "discovery of the nature and mode of action of the respiratory enzyme.
WARNBURG EFFECT : cancer cells under aerobic (well-oxygenated) conditions to metabolize glucose to lactate (aerobic glycolysis) is known as the Warburg effect. Warburg made the observation that tumor slices consume glucose and secrete lactate at a higher rate than normal tissues.
2. 2
Aim
GEOL 541 Dr. Perveiz Khalid
To understand:
basic concepts of seismotectonics
Seismotectonics zonation
the role of seismotectonics in earthquake
hazard analysis
3. 3
Outline
Introduction
Concept of plate tectonics
Seismicity and plate boundaries
Seismotectonic maps
Seismotectonic Zonation
Seismotectonic zones of Pakistan
GEOL 541 Dr. Perveiz Khalid
4. 4
Introduction
Seismic waves provides the information about active, present
day existing processes in the subsurface.
Analysis (qualitative & quantitative) of earthquake faulting
characteristics such as
• Fault orientation,
• Sense of slip,
• Net cumulative displacement along the fault plane
played the major role in evolution of the theory of plate tectonic.
GEOL 541 Dr. Perveiz Khalid
5. 5
What is Seismotectonics?
The spatial distribution of earthquake may be
used to determine the location of plate boundaries,
faults, direction of relative motion between the plates,.
The rate of earthquake occurrence in some
particular area, and the cumulative displacement of
earthquake occurrence can be bused to infer the
relative velocity between the plates.
GEOL 541 Dr. Perveiz Khalid
6. 6
What is Seismotectonics?
The study of the relationship between the
earthquakes, active tectonics and individual faults of a
region.
OR
The study of active faulting, and its relationship to
plate motion and lithospheric properties.
GEOL 541 Dr. Perveiz Khalid
7. 7
Significance
To understand which faults (seismic source) are responsible for seismic activity
in an area by analyzing a combination of
regional tectonics
recent instrumentally recorded events
accounts of historical earthquakes
geophysical data
This information can then be used to quantify the seismic hazard of an area.
GEOL 541 Dr. Perveiz Khalid
8. 8
Concept of Plate Tectonics (1)
Earthquakes are closely related to tectonic activities, therefore, it is
necessary to understand basic concept of plate tectonics.
Mobile lithosphere concept
GEOL 541 Dr. Perveiz Khalid
9. 9
Concept of Plate Tectonics (2)
Lithosphere: Highly viscous region, movement involve shearing
motion at the boundaries and produced shear-faulting
earthquakes.
Asthenosphere: relatively less viscous
Mesosphere: relatively viscous
GEOL 541 Dr. Perveiz Khalid
10. 10
Seismicity and plate boundaries (3)
Release of strain energy by seismic events is restricted to inhomogeneous stress
regions. i.e., plate boundaries
GEOL 541 Dr. Perveiz Khalid
Plates
A. Pacific
B. North
America
C. Cocos
D. Nazca
E. South
America
F. Caribbean
G. Antarctic
H. Indian
I. Philippine
J. African
K. Eurasian
L. Arabian
Boundaries
1. Aleutian SZ
2. San Andreas Fault
3. Central American
SZ
4. Antilles Sz
5. South American SZ
6. Scotia SZ
7. East Pacific Rise
8. Tonga-Kermadec
SZ
9. New Hebrides SZ
10. Mariana SZ
11. Japan SZ
12. Indonesian SZ
13. Hindu Kush
14. Mid Atlantic Rise
A
K
J
I
H
G
F
ED
C
B
L
1
9
8
7
6
5
4
1432
13
12
11
10
11. 11
Seismicity and plate boundaries (4)
Seismotectonic zones are concentrated near to the plate boundaries.
Divergent boundaries: Two plates are moving apart and new lithosphere is
produced (or old lithosphere is thinned). E.g., midoceanic ridges, continental rifts
Convergent boundaries: Litjosphere is thickened or consumed by sinking into
the mantle. E.g., subduction zones, alpine belts
Transcurrent boundaries: plates move past one another without either
convergence or divergence. E.g., transform faults, strike-slip faults
GEOL 541 Dr. Perveiz Khalid
12. 12
Seismicity and plate boundaries (5)
Divergent and transcurrent plate boundaries are
characterized by shallow seismicity (focal depth < 30 km).
GEOL 541 Dr. Perveiz Khalid
13. 13
Seismotectonic Maps
Show:
geology (structure)
geomorphology
water features
faults (orientation, geometry, fault plane etc.)
lineaments
shear zone
past earthquake events
GEOL 541 Dr. Perveiz Khalid
14. 14
Main elements of map
Seismicity: A careful study and compilation of data will be devoted to the
historical and instrumental seismicity. Regional and local maps may include
earthquake magnitude as low as M 1 but the final seismotectonic map will have to
consider magnitudes large than M 4.
Active tectonics and faulting:
Plate movement sketch (with kinematic indicators).
Plate sketch map with principal stress direction.
Explanatory notes (including a more comprehensive description of the
oceanic.
GEOL 541 Dr. Perveiz Khalid
15. 15
Seismotectonic Zonation
A seismotectonic zone is considered to be a geographic region of some
geological, geophysical and seismological similarity with a uniform earthquake
potential.
In a particular seismotectonic zone, the seismicity (earthquakes etc.) is
assumed uniform & homogeneous throughout the zone.
Seismotectonics zonation provides the basis for Seismic Hazard Assessment
(SHA) of any area.
GEOL 541 Dr. Perveiz Khalid
17. 17
Preparation of seismotectonic zones
Regional tectonics
Integrated data sets
Geomorphology
Earthquake records
Scale
Limitations
GEOL 541 Dr. Perveiz Khalid
18. 18
Regional tectonics
An understanding of the regional tectonics of an area is
likely to be derived from
published geological maps
research publications on the geological structure and
seismic reflection data (2D, 3D)
GEOL 541 Dr. Perveiz Khalid
19. 19
Geomorphology
Seismically active faults and related fault generated folds have a direct
effect on the geomorphology of a region.
This may allow the direct identification of active structures not
previously known.
In some cases such observations can be used quantitatively to constrain
the repeat period of major earthquakes.
GEOL 541 Dr. Perveiz Khalid
20. 20
Integrated data sets
Seismotectonic zonation of an area requires the integration of a large number
of disparate datasets:
1. Satellite images (remote sensing)
2. Digital elevation models
3. Geodic maps (conventional geodesy, GPS data)
4. Earthquake/ seismicity data
Instrumentally recorded events
Historical records
Field investigations
5. Geophysical data (gravity, magnetic, seismic profiles and tomography).
GEOL 541 Dr. Perveiz Khalid
21. 21
Earthquake: Instrumental records
Sufficient information has been available from seismometers to allow the
location,
depth and
magnitude
of earthquakes to be calculated.
In terms of identifying the fault responsible for an earthquake where
there is no clear surface trace, recording the locations of aftershocks
generally gives a strong indication of the strike of the fault.
GEOL 541 Dr. Perveiz Khalid
22. 22
Earthquake: Historical records
To understand the long-term seismicity of an area, information from
earthquakes before the era of instrumental recording are required.
Careful assessment of historical data in terms of their reliability is
mandatory.
In most cases, all that can be derived is an estimate of the location and
magnitude of the event. However, such data is needed to fill the gaps in the
instrumental record, particularly in areas with either relatively low seismicity or
where the repeat periods for major earthquakes is more than a hundred years.
GEOL 541 Dr. Perveiz Khalid
23. 23
Earthquake: Field investigations
Information on the timing and magnitude of seismic events that occurred
before instrumental recording can be obtained from excavations across faults
that are thought to be seismically active and by studying recent sedimentary
sequences for evidence of seismically active faults.
Seismically active faults and related fault generated folds have a direct effect
on the geomorphology of a region. This may allow the direct identification of
active structures not previously known. In some cases such observations can be
used quantitatively to constrain the repeat period of major earthquakes.
GEOL 541 Dr. Perveiz Khalid
24. 24
Seismotectonic zones of Pakistan
GEOL 541 Dr. Perveiz Khalid
1. Kohistan-Kashmir
2. Northern Baluchistan
3. Quetta-Sibi
4. Southern Baluchistan
5. Northern Afghanistan-
Tajikistan
6. Hindu Kush
7. NW Afghanistan-
Tajikistan Border Region
8. Eastern Afghanistan
9. Makran Coast
10. Runn of Kuchch
11. Sindh-Punjab
12. Pamir-Kunlun
13. Indian Kashmir
14. Upper Punjab-NWFP
15. Chitral
16. Koh e Sulaiman
17. South West Iran
18. Western Baluchistan
Based on seismicity, geology, source mechanism and the stress direction of the region,
Pakistan is divided into 19 (18) seismotectonic zones.
25. 25
Seismicity map of the NW Himalayan Fold-and-Thrust Belt for pre-
instrumental (pre-1904) and instrumental (post-1904-2006) earthquakes.
GEOL 541 Dr. Perveiz Khalid
Plates
A. Pacific
B. North
America
C. Cocos
D. Nazca
E. South
America
F. Caribbean
G. Antarctic
H. Indian
I. Philippine
J. African
K. Eurasian
L. Arabian
Boundaries
1. Aleutian SZ
2. San Andreas Fault
3. Central American
SZ
4. Antilles Sz
5. South American SZ
6. Scotia SZ
7. East Pacific Rise
8. Tonga-Kermadec
SZ
9. New Hebrides SZ
10. Mariana SZ
11. Japan SZ
12. Indonesian SZ
13. Hindu Kush
14. Mid Atlantic Rise
26. 26
Seismotectonic zonation map of the NW Himalayan Fold-and-Thrust Belt for
the period 1904-2006.
GEOL 541 Dr. Perveiz Khalid
Plates
A. Pacific
B. North
America
C. Cocos
D. Nazca
E. South
America
F. Caribbean
G. Antarctic
H. Indian
I. Philippine
J. African
K. Eurasian
L. Arabian
Boundaries
1. Aleutian SZ
2. San Andreas Fault
3. Central American
SZ
4. Antilles Sz
5. South American SZ
6. Scotia SZ
7. East Pacific Rise
8. Tonga-Kermadec
SZ
9. New Hebrides SZ
10. Mariana SZ
11. Japan SZ
12. Indonesian SZ
13. Hindu Kush
14. Mid Atlantic Rise
27. 27
Seismic Hazard Analysis
In order to understand the seismic hazard of an area it is necessary not only to
know where potentially active faults are, but also the orientation of the stress
field. This is normally derived from a combination of earthquake data, borehole
breakout analysis, direct stress measurement and the analysis of geologically
young fault networks. The World Stress Map Project provides a useful online
compilation of such data
GEOL 541 Dr. Perveiz Khalid