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Title: Monitoring Earthquakes in the U.S. Midcontinent:


1
Monitoring Earthquakes in the U.S. Midcontinent
From Seismic Hazards to Crustal Structure
Tina M. Niemi UMKC Department of Geosciences
2
  • Outline
  • Crustal structure - Archean to Proterozoic
  • Formation of the Reelfoot Rift
  • Earthquakes on the New Madrid Seismic zone
  • Earthquakes on the Nemaha structure
  • Earthscope
  • Central Plains Earthscope Partnership

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1850 ma
1850 ma
1000 ma
1750 ma
1630 ma
300 ma
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Rodinia - NeoProterozoic
http//www.uky.edu/KGS/emsweb/ecrb/pcrift2.html
http//www.palaeos.com/Earth/Geography/Rodinia.htm
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Ouachita Orogeny - Pennsylvanian
Laurentia
300 ma
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Pangaea
http//www.scotese.com/
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http//www.dnr.mo.gov/geology/geosrv/geores/Unders
tandEQs.htm
11
Large Earthquakes in the United States New
Madrid 1811-1812 December 16, 1811, January 23,
1812, February 7, 1812 Judging from newspaper
accounts of damage to buildings, the February 7
earthquake was the biggest of the three.
12
Congress passed in 1815 the first disaster relief
act providing the landowners of ravaged ground
with an equal amount of land in unaffected
regions.
Stumps of trees killed by the sudden submergence
of the ground can still be seen in Reelfoot Lake,
TN.
Sandblow dike indicating paleoliquefaction in the
New Madrid area (photo by USGS
Isoseismal map
Liquefaction
Sourcehttp//www.showme.net/fkeller/quake/liquef
action.htm
13
Existing Permanent Broadband Stations in the
Region
The major reason for the uneven distribution of
seismic stations Difference in seismic
activities
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Seismic Hazards Peak Acceleration Probability
source USGS Earthquakes Hazard program
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The Humboldt fault lies along the eastern
boundary of the Nemaha Ridge.
16
New epicentral locations are marked by circles.
The tails represent the vector from the previous
locations to the new epicentral locations. The
positive midcontinent Bouger gravity anomaly is
also shown. The Nemaha Ridge and Humboldt fault
(NRHF), Midcontinent rift system (MRS), and
Mansfield- Bolivar tectonic zone (MBTZ) are
labeled.
Relocation of the Kansas-Nebraska earthquakes
from the Kansas Catalog (1977-1985) plotted on a
shaded relief topographic map of the region.
17
Manhattan, Riley County, Kansas ? 1867 04 24
2022 M 5.10 Wamego Earthquake Isoseismals for
the largest known earthquake in Kansas, MM
intensity index contoured. Site effects along
the E-W Kansas River valley may distort the 1867
isoseismal pattern.
DuBois and Wilson (1978) List of Earthquake
Intensities for Kansas, 1867-1977.
?
18
A.D. 1450, A.D. 900, A.D. 300 and 2350 B.C.
19
Detecting small earthquakes
MicroseismicityKansas Catalog (1977-1989)
Niemi, T.M., Ferris, A.N., and Abers, G.A., 2004,
Investigation of microearthquakes, macroseismic
data, and liquefaction associated with the 1867
Wamego earthquake in eastern Kansas Bulletin of
the Seismological Society of America, v. 94, no.
6, p. 2,317-2,329.
20
Shake map (from Susan Hough, USGS) comparison for
New Madrid and Landers earthquakes.
When large New Madrid earthquakes do occur, the
effects will be significant and very widespread
(due to low attenuation of seismic wave
propagation in eastern N. America)
21
Historical Seismology
  • Isoseismal Map--map contoured with equal
    earthquake intensity.
  • Roman numerals indicate estimated Modified
    Mercalli intensities for a 6.6 magnitude
    earthquake.
  • Structural damage
  • Liquefaction
  • Sand blows
  • Based on maps in W. Atkinson, 1989, The Next New
    Madrid Earthquake, Southern Illinois University
    Press

Near Charleston, Missouri Oct. 31, 1895
Magnitude 6.6
22
  • Modified Mercalli Intensity scale
  • I Barely felt
  • II Felt by a few sensitive people, some suspended
    objects may swing
  • III Slightly felt indoors as though a large truck
    were passing
  • IV Felt indoors by many people, most suspended
    objects swing, windows and dishes rattle,
    standing autos rock
  • V Felt by almost everyone, sleeping people are
    awakened, dishes and windows break
  • VI Felt by everyone, some are frightened and run
    outside, some chimneys break, some furniture
    moves, slight damage
  • VII Considerable damage in poorly built
    structures, felt by people driving, most are
    frightened and run outside
  • VIII Slight damage to well built structures,
    poorly built structures are heavily damaged,
    walls, chimneys, monuments fall
  • IX Underground pipes break, foundations of
    buildings are damaged and building shift off
    foundations, considerable damage to well built
    structures
  • X Few structures survive, most foundations
    destroyed, water moved out of banks of rivers and
    lakes, avalanches and rockslides, railroads are
    bent
  • XI Few structures remain standing, total panic,
    large cracks in the ground
  • XII Total destruction, objects thrown into the
    air, the land appears to be liquid and is visibly
    rolling like waves.

23
Although earthquakes in the central and eastern
United States are less frequent than in the
western United States, they affect much larger
areas. This is shown by two areas affected by
earthquakes of similar magnitude-the 1895
Charleston, Missouri, earthquake in the New
Madrid seismic zone and the 1994 Northridge,
California, earthquake. Red indicates minor to
major damage to buildings and their contents.
Yellow indicates shaking felt, but little or no
damage to objects, such as dishes.
24
Northridge, California, 1994 Photograph by Peter
Weigand January 1994 magnitude 6.7 earthquake.
25
EarthScope
EarthScope is the first Major Research Equipment
and Facilities Construction (MREFC) investment
for NSF Earth Science Research goal Explore
the structure and dynamics of the North American
Continent Education goal Provide opportunities
for all ages to participate in a national
scientific experiment.
  • San Andreas Fault
  • Observatory at Depth
  • (SAFOD)
  • Plate Boundary
  • Observatory
  • (PBO)
  • Seismic Observatory
  • (USArray)

Source http//www.earthscope.org
26
EARTHSCOPE all stations
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University Siting Assistance
  • Universities in some states are helping to find
    sites in that region
  • Provides students an opportunity to participate
    in a major research project
  • Students work in pairs
  • Final selection and permitting handled by TA
    staff
  • Promotes active involvement of wider Earth
    science community
  • Effective use of local knowledge and interaction
    with local communities

29
2008 Summer Siting Plans
  • 326 sites will be identified in
  • North Dakota (37 sites)
  • South Dakota (43 sites)
  • Nebraska (43 sites)
  • Kansas (43 sites)
  • Oklahoma (39 sites)
  • Texas, excluding Big Bend (121 sites)
  • Will enable permits for the remainder of 2008,
    all of 2009, and into 2010
  • Two 4-day training workshops are being organized

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Construction Period
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Digging the vault and trenching for cables
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Preparing the hole for the vault
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Burying the vault and cables
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Seismic sensor (seismometer) digital recorder,
and telemetry electronics in vault
35
Final site with power, cell modem antenna, and
GPS antenna
36
Satellite VSAT uplinks
AC
Solar
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Central Plains Partnership
CPEP
NE IA KS MO
The Central Plains EarthScope Partnership (CPEP)
is a coalition of universities, schools, state
geological surveys, and state and federal
agencies organized to promote earth science
research and education in the four states of
Kansas, Nebraska, Iowa, and Missouri by utilizing
the NSF-funded EarthScope facility. CPEP
Goals Coordinate conversion of 1/10 of the
USArray stations into permanent stations for
long-term monitoring, research, and education
through private, state, and federal ownership.
Partner with the USArray Facility to select
sites for the transportable array. Educate and
enhance the public awareness and knowledge of
EarthScope, earthquakes, and earth structure in
the Central Plain states through development of
programs and materials. Promote
EarthScope-related outreach activities in the
Central Plains states.
39
During 2009 and 2010, approximately156
transportable three-component, broadband
seismometers will be installed every 70 km (43
mi) across Kansas, Nebraska, Iowa, and Missouri
as part of the NSF-funded EarthScope USArray.
40
Yet USArray deals with much more than earthquake
distribution
Receiver function studies (azimuth variation in
crust) Seismic tomography Shear wave splitting
(mantle anisotropy)
Velocity structure of the mantle from seismic
tomography van der Lee and Frederiksen, 2005
Horizontal slices at three different depths
showing azimuthal anisotropy in the NA upper
mantle. Model was obtained by joint inversion of
surface waveforms and SKS splitting measurements.
Marione and Romanowicz 2007, Nature
41
Bouguer gravity map and major tectonic features
of the Central Plains and adjacent areas. Blue
lines separate crustal blocks with different
ages, which become progressively younger toward
the south. The permanent seismic network would
enable a significantly improved understanding
about the formation, evolution, and structure of
these tectonic features and their roles in the
formation and distribution of earthquakes in the
Central Plains.
  • Major features to be studied by the CPEP
    permanent seismic network
  • MCR
  • Boundaries of tectonics units
  • NMSZ

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Recorded at UMKC.
Seismogram of Mw 5.2 earthquake that occurred in
Southern Illinois on April 18, 2008. The event
was recorded at UMKC UTC 093818 by an AS-1
seismograph.
Magnitude 5.2 Mt. Carmel, ILLINOIS Friday, April
18, 2008 at 093700 UTC
http//www.earthquake.usgs.gov/
44
Mt. Carmel, IL www.pantagraph.com/
Louisville, KY
45
Thank you
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