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 |  Subject: New Madrid Seismic Zone graphics, illustrations, diagrams  Thu 23 Aug 2012, 10:17 | |
| New Madrid Seismic Zone graphics, illustrations, diagramsNatural gas pipelines & NMSZMap pages 1 | 2 | 3 | 4 | 5 | 6 | aerials
This company (above) delivers Billions of cubic feet of gas per year
through 19 major pipelines. Note how the pipelines cross the New Madrid
Seismic Zone. Click map to their website.
"You have four of the five major natural-gas pipelines come
right through the soup in New Madrid, the soft alluvial soil," says
Gray. "They carry gas all the way to Detroit, Chicago, Indianapolis and
Pittsburgh. If (the earthquake) happened during the winter, you're going
to have major-league problems on your hands. Try to explain to somebody
why you cannot heat a nursing home or keep a hospital warm."
-- Ed Gray, Missouri State Emergency Management Agency (SEMA)
Riverfront Times
An earthquake in the middle of the country, along the precarious New
Madrid fault, could have enormous fiscal and energy consequences. "Virtually
every natural gas pipeline in the nation is built over that fault,"
Geller says. "You'll see the explosion reflected off the moon."
--insurancenewsnet.com
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|  The main production areas and pipeline routes for natural gas (American Gas Association)
|  The graphics immediately above and below are from a Feb 09 PDF (3 meg) from Argonne Labs. Note from above... TEN pipelines. From below: several high voltage towers and transmission lines. Widespread multiple failures would take longer to repair. 
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|  above: typical pumping station along a gas pipeline. below: Texas Eastern pipeline crosses Mississippi river at Grand Tower IL  
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Meeman/Shelby / Porter's Gap Fault in West Tennessee
We may hear more about it, or others like it. - says geologist Roy Van Arsdale..
It runs along the bluffs just NW of Memphis. Has been dormant. Could
devastate Memphis if it cut loose.
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Most SBC/AT&T phone office switching buildings in Missouri's
Bootheel were retrofitted in the 1990s to withstand a good shake.
Pictured is in Charleston. Click pic for more.
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50-60ka means 50,000 to 60,000 years ago. Holocene means last 10,000 |  | 
A magnitude 4+ quake southeast of Cairo near Bardwell KY in 2003. USGS
map from a PDF poster shows entire New Madrid region (above). |
<blockquote> Wide map of New Madrid Seismic Zone</blockquote> <blockquote> 2003: Kentucky Emergency officials see the hazard as less serious PDFSeth Stein of Northwestern University sees threat as less serious </blockquote> "NEW MADRID really scares me," said Jim Wilkinson, director of the Memphis- Central United States Earthquake Consortium, ( cusec.org
) an eight-state emergency preparedness group. "If New Madrid goes on
the scale that we think it will ... we are going to impede the entire
country.
"All of the commerce, all of the oil and gas
pipelines, everything comes right the central U.S.," Wilkinson said.
"You drop the bridges across the Mississippi and Missouri rivers and the
river locks and you've frozen this country." But Ky State Geologist Jim
Cobb disagreed with the level of risk.
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|  Main New Madrid quakes of 1811-12
|  New Madrid area sandblows
|  New Madrid area showing mafic intrusions, plutons (iron type material that came up from earth's liquid core through cracks caused by ancient continents moving, faulting, earthquakes). Earthquakes tend to be near / between plutons. Illustrations above are from nrc.gov
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|  Seismic Zones near, north, east of New Madrid area
|  Fault Segmentation and possible rupture scenarios, New Madrid Fault
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BA Blytheville Arch
BFZ Blytheville Fault Zone
BL Bootheel Lineament (now designated as fault)
NN New Madrid North
RF Reelfoot Fault
NW New Madrid West (Not shown here, see below)
RS Reelfoot South (Not shown here, see below)
-- NW and RS are defined solely from seismicity
| In recent years, numerous minor earthquakes or "microearthquakes"
have revealed the presence of three deep subsurface faults in the New
Madrid area. Two of the faults are southwest-northeast trending
right-lateral strike-slips.
The southernmost strike-slip is called the Blytheville seismic zone
and runs at least 70 miles from Arkansas through Missouri and into
Tennessee. The other strike-slip fault is called the New Madrid north
zone.
The third fault or Reelfoot fault, is a southeast-northwest trending
reverse fault, which is located between the two strike-slip faults. On
the reverse fault, the rocks on the southwest side move up relative to
the rocks on the northeast side.
The main shock on December 16, 1811 may have been associated with
activity on the southernmost strike-slip fault or the Blytheville
seismic zone. The January 23, 1812 quake may have originated from the
strike slip fault in the New Madrid north zone.
Radiocarbon dating of wood in the remains of ancient seismic
features, including old sand blowouts, suggest that significant
earthquakes occurred in the New Madrid system between 780 and 1000 AD,
1180 and 1650 AD, and 4,000 to 5,000 years ago. Magnetic measurements
and studies of seismic waves that pass through the subsurface bedrock of
the region indicate that the rocks around the New Madrid system have
not been overly deformed over the past 300 million years.
Like other rift zones, the Reelfoot Rift is a sunken linear valley
bounded by normal faults. The normal faults run southwest-northeast. The
rift formed about 600 million years ago, but spreading stopped before
the North American plate could be broken in two. Tectonic activity
restarted in the rift zone about 100 million years ago during the age of
the dinosaurs. Lava erupted out of the normal faults, perhaps from a
hotspot that now exists near Bermuda. Currently, we don't know if the
periodic earthquakes in the New Madrid fault system are related to a
slow reactivation of the Reelfoot Rift zone or not.
Reference books: Hyndman and Hyndman, Sieh and LeVay
above credit David Rodgers, UM Rolla
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| The Bootheel Lineament
was termed a "fault" in 2003 after scientists dug and found
displacement they had suspected. Click the illustration above for the
story.
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|  | (above): Earthquake epicenters in the NMSZ and surrounding regions projected onto a topographic base map.
Modern earthquake data (for events M>2 since 1974, dark blue dots) are from the NEIC and CERI Catalog (1974-2003);
pre-1974 and historic earthquake data (M>5, red dots) are from Stover and Coffman [1993].
Yellow dots: large 1811-1812 events [Stover and Coffman, 1993]. |
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Above: Some researchers focus on coulomb stress change and say there is a
greater chance of quakes just outside the New Madrid Seismic zone than
inside it. |  |
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DescriptionMagnitudeFrequency per year | Great | 8.0+ | 1 | | Major | 7.0-7.9 | 18 | | Large (destructive) | 6.0-6.9 | 120 | | Moderate (damaging) | 5.0-5.9 | 1,000 | | Minor (damage slight) | 4.0-4.0 | 6,000 | | Generally felt | 3.0-3.9 | 49,000 | | Potentially perceptible | 2.0-2.9 | 300,000 | | Imperceptible | less than 2.0 | 600,000+ |
<blockquote> From Earthquakes and the Urban Environment, Vol. 1, G. Lennis Berlin, 1980How Many Earthquakes Happen Every Month? Day? Minute?Using the previous table: </blockquote> Per month..........................................Approximately 80,000
Per day.........................................Approximately 2,600
Per minute..................................Approximately 2
from CERI - Memphis
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