GEOLOGY     oelbohr.wmf (14422 bytes)

Updated 14-Mrz-11 02:30h

Earthquakes, especially in Japan, March 2011

An earthquake is a vibration of the Earth (Moon - a moonquake, and similarly the quakes of other bodies, such as planets, their satellites and the Sun). The Earth is an inhomogeneous body: even its uppermost solid layer, the crust, consists of about 7 large blocks called plates and many smaller ones, called microplates, terranes etc.. All the blocks are slowly drifting, each with a various speed (centimeters per year) and direction. The forces driving the plates are assumed to be related to a deep (mantle) convection and differential tidal (gravitational) attractivities.  Relatively, there are two mutual motion directions:

1) divergent one, in which the plates and microplates separate by a growing new crust; Example: the Midatlantic ridge. This relative motion is associated with "smooth" release of magma - a "peaceful" volcanism, such as on and around Island, without any pressure cumulation and therefore without any vibration and earthquake.

2) convergent one, in which one of the plates is pressing on or submerging beneath the other one, so called subduction. The convergence creates pressure, which may at places cumulate until a breakage. The breakages are the places of abrupt shifts starting vibrations which propagate through the plates as earthquakes. Shifts of the ocean floor may produce tsunamis, which are special water waves with unusually long wavelength (see below).

The vibrational energy dissipates from the point of the earthquake focus (origin) with the distance mostly horizontally, therefore the energy decreases with the square of the distance, sometimes also downwards, which increases the dissipation distance exponent up to about 2.5 .

Earthquake destructive effects are due to the response of the solid bodies on the Erth's surface: various rocks, having different density, react differently due to their specific inertia and usually anisotropic hardness and may deform and even separate first on discontinuities. A protection of human property and lives is based on our knowledge of the territory mechanical properties, partially revealed by their earthquake history. The protective principle attempts to mechanically separate our property (constructions etc.) from the ground expected to vibrate. The ideal separation may be understood as materialized by a suspension in the air, an easy compressible gas with a minimum possible friction (viscosity), for example a baloon suspension  Even this is an impractible example, it illustrates well the protective method.

 

Nitrates in drinking water in the Sembach area
Kaiserslautern American, the AvantiPro weekly, reported in the May 15, 2009 (vol. 33, Nr. 19, page 4) issue:
If the nitrates contaminate the drinking water, they represent the most soluble anion, which can not be chemically bound to any metal. The 435th Medical Group Bioenvironmental Engineering Flight regularly monitors drinking water quality for many constituents throughout the year. The quarterly sampling for nitrates for Sembach Annex revealed an elevated level. The maximum contaminant level for nitrates is 10 milligrams per liter and the reportable level from recent results is 13 mg/l. ...
http://www.kaiserslauternamerican.com/article.php?i=10166
Upon request, Mr. Scott Vincent, PE, Chief, Programs Flight, emailed me the following information:
Nitrate is the common form of inorganic nitrogen found in water solution. In agricultural regions, heavy fertilizer application results in unused nitrate migrating down into the groundwater. As a result, groundwater withdrawn by private and public wells is likely to have measurable concentrations of nitrate, and in the same regions well waters in many rural communities can exceed the recommended limit of 10 mg/l of nitrate nitrogen. Surface waters can be contaminated by nitrogen from both discharge of municipal wastewater and drainage from agricultural lands. The health hazard of ingesting excessive nitrate in water is infant methemoglobinemia. In the intestine of an infant, nitrate can be reduced to nitrite that is absorbed into the blood oxidizing the iron of hemoglobin. This interferes with oxygen transfer, resulting in cyanosis and giving the baby a blue color. During the first 3 months of age, infants are particularly susceptible. Incidents of infant methemoglobinemia are extremely rare since most mothers in regions of known high-nitrate drinking water use either bottled water or a liquid formula requiring no dilution. Methemoglobinemia is readily diagnosed and rapidly reversed by injecting methylene blue into the infant's blood. Healthy adults are able to consume large quantities of nitrate in drinking water without adverse effects. The principal sources of nitrate in the average adult diet are saliva and vegetables amounting to about 130 mg/day. Two liters per day at 10 mg/l equals only 20 mg/day. Justified by epidemiological evidence on this occurrence of methemoglobinemia in infants, the standard of 10 mg/l is the maximum contaminent level for water with no observed adverse health effects. - Water Supply and Pollution Control, 5th Edition, Viessman & Hammer, Harper Collins College Publishers, 1993.

A short note about GEOL-120 and GEOL-110 LAB appeared in Kaiserslautern American, the AvantiPro weekly, the May 28, 2009 issue. Thank you, Nicky (Editor):
http://www.kaiserslauternamerican.com/article.php?i=10269

This recent report is important for the following courses, currently scheduled at Kaiserslautern KAPAUN, summer term (June-July), MoWe:

MAG 7.7 Earthquake shakes the Banda Sea floor, Fri, 27-Jan-06, 16:58:48h UTC, Fri, 27-Jan-06, 17:58:48h MidEuropean Time,
local time: Sat, 28-Jan-06, 1:58:48h; hypocenter  ≈351.7 km deep.

Location:  5.462°S, 128.096°E

USGS Naional Earthquake Information Center, World Data Center for Seismology, Denver, released a Preliminary Earthquake Report:
"
A major earthquake occurred 195 km (120 miles) S of Ambon, Moluccas, Indonesia. The magnitude and location may be revised when additional data and further analysis results are available. There have been no reports of damage":

Last USGS NEIC FELT REPORT (28-Jan-06, 14:00h UTC):
Felt (V) on Ambon; (IV) at Kupang, Saumlaki, Sorong, Tual, and Waingapu; (III) at Makassar, Indonesia. Felt (V) at Dili, East Timor and (III) at Darwin, Australia. Also felt at Humpty Doo-MacMinns Lagoon, Australia.

http://earthquake.usgs.gov/eqinthenews/2006/usika7/
http://earthquake.usgs.gov/recenteqsww/Maps/10/125_-5.html

Replacement of Microscopes:

http://www.aperio.com/

Dangerous Phenomena such as Hurricans

"Preparation through education is less costly than learning through tragedy."
- MAX MAYFIELD, DIRECTOR
NATIONAL HURRICANE CENTER

GEOGRAPHICAL CENTER of the Continent EUROPE
The National Geographic Institute of France, Paris (Institut Géographique National) defined it as a point 26 km N from Vilnius, the capital of Lithuania, towards Moletai, near the Purnuskes village, already in 1989:
http://www.ign.fr

There were performed several calculations of the Center of Europe in the history:
http://en.wikipedia.org/wiki/Geographic_centre_of_Europe

# date location author coordinates
1 1775 town Suchowola, NE Poland Szymon Antoni Sobiekrajski, cartographer & astronomer 53°35′ N 23°06′ E
2 late 18th century St. John's Church, village Krahule on the road to Kremnické Bane, near Kremnica, central Slovak Republic Legend 48°45′ N 18°55′ E
3 1887 Dilove on the Tisza river, Rachiw, Galicia, SE Ukraine (near Romania) Austrian geographers 47º 56' 3" N, 24º 11' 30" E
4 >1900 Frauenkirche church, Dresden, the Saxon capital, Germany German geographers  
5 1910 hill Dyleň, 939 m/m, W of Marienbad, W Czech Republic Austrian geographers  

6

after WW2

Hildweinsreuth near Flossenbürg, N Oberpfalz, Bavaria, Germany (south from the location above)

Geographic Institute, University München, Germany

7 near the city Toruń, about 350 km east of the border with Germany, 150 km south of Gdańsk, 200 km NW of the Polish capital Warsaw. unknown
8   memorial W from České Budějovice, S Czech Republic unknown  
9 1989 26 km N from Vilnius, the capital of Lithuania, towards Moletai, near the Purnuskes village Jean-George Affholder, Institut Géographique National, Paris, France 54° 51' N, 25°19' E
below the Earth surface
10 1-MAY-2005 Kleinmaischeid, near Neuwied, 40 km SE from Bonn, N of Koblenz, Germany Center of EU: Institut Géographique National, Paris, France  

The surprisingly far north and far east position in Lithuania is caused by the European limits:
west at Azores Islands, south at Canaries Islands, north at Spitzbergen, Norway, and east at the Urals, Russia.
http://en.wikipedia.org/wiki/Extreme_points_of_Europe

Note: the determinations may be based on various criteria, but have no scientific value.
http://home.no.net/enklaver/other.htm

MAG 7.2 Earthquake shakes Japanese coast, Tue, 16-Aug-05, 02:46:30h UTC,  (near epicenter: Tue Aug 16 11:46:30h)
http://www.geotimes.org/current/WebExtra081605.html

http://earthquake.usgs.gov/recenteqsww/Quakes/usbvae.htm

MAG 9.0 - 4th Strongest Earthquake since 1960:
Sunday, 26-DEC-04,
off the west coast of northern Sumatra

There was a strong (MAG 9.0) earthquake on the Indian Ocean floor in South-East Asia, at the site where the India + Australia lithospheric plates are subducted beneath the south-east margin of the Eurasia plate, which is there separated by the microplates of Burma and Sunda (tectonic settings). See also EQflyer.doc.

Astronomic View at the Involved Geologic Phenomena

On Sunday, 26-DEC-04, the Earth, in its slightly elliptical orbit around the Sun, our nearest star, was approaching its closest distance from the Sun, which is attained on 4-JAN. In so doing, the Earth movement accelerated. The curvature of its path developed exactly the centrifugal force that maintains the orbit in which the Earth will neither fall onto the Sun nor escape from it.

On Sunday, 26-DEC-04, the Moon, in its elliptical orbit around the Earth which is nearly in the same plane as ecliptic, the Earth's orbital plane (only 5° tilt), arrived at a position outside of the Earth's orbit around the Sun. In fact, it was located almost exactly on the Sun - Earth line, but on the opposite side from the Sun. This time from the Earth, we see that the Moon is completely illuminated by the Sun and call it full moon. In this arrangement of these three cosmic bodies, due to their extreme mutual closeness, they interact by their force of gravity.

Though the Sun is huge and the Moon is small, we see both in a similar angular size (as known from the solar eclipse). This "apparent (angular) size compensation" is caused by their inversely related distances. The Earth - Moon distance is 3.844 x 105 km ±5.5% and the Earth - Sun distance is 1.495979 x 108 km ±1.7%. The Moon's diameter is 3.476 x 103  km and the Sun's diameter is 1.392 x 106 km, enough to swallow the Moon's orbit around the Earth. Similarly, even the incredibly great ratio of the masses (responsible for their gravitational forces) of the Sun (1.989 x 1030 kg) to that of the Moon (7.35 x 1022 kg) is overcompensated by the inverse proportionality of their cubed distances to the Earth, mathematically: (mSun/mMoon)x(aMoon/aSun)3 ≈ 0.46, where m is mass of the Sun and Moon respectively, a is the distance to the Earth of the Sun and Moon respectively (equation 4.17 in MURRAY & DERMOTT, 1999, page 135). This is why the Sun's gravity pull on the Earth is 45.9 % of the Moon's gravity pull only. Dermot states that the tide raised in the Earth's crust by the Moon is 36 cm, while that by the Sun is 16 cm.

At 7:58h local time at the earthquake site, the Sun rose to about 30° above the eastern horizon and the full Moon set to that same angle below the western horizon. These two cosmic bodies, at 180° around the Earth, have been strongly stretching (flexing) our planet by their gravity. This gravitational (tidal) force is acting not only on the waters, but also on the atmosphere and lithosphere (solid Earth's surface, see above). Within the solid Earth's surface, the flexing (changing deformation) has to focus on the large lithospheric discontinuities (faults), preferably those with an approximate North - South direction in the given location. The extraterrestrial gravity forces strongly change their pressure on the plates,  the Burma plate overriding westwards the India and Australia plates (the movement direction of the celestial bodies in the sky due to the Earth's rotation). There is a probability that a crustal slip on a major discontinuity causing earthquake could be triggered by the tidal flexing forces, particularly when the tide is strongest, such as the full and new moon positions of the nearby cosmic bodies. According to the standard rebound theory of earthquakes, a temporarily blocked plate drifting, leading to an increasing rock compression has abruptly been released: perhaps by the tidal flexing.

That devastating megathrust earthquake occurred at the interface of the India and Burma plates. The India plate as a gigantic spring released its stress, which developed as the India plate was subducted beneath the Burma microplate. The India plate begins its descent into the mantle at the Sunda trench, which lies about 100 km to the west of the earthquake’s epicenter. The trench is the surface (submarine) expression of the Australia & India plate subduction beneath the Burma & Sunda plates, situated to the northeast.

In the region of the earthquake, the India plate moves toward the northeast at a rate of 6.1 cm/year relative to the Burma plate. This results into oblique convergence at the Sunda trench. The oblique motion is partitioned into thrust-faulting, which occurs on the plate-interface and which involves slip directed perpendicular to the trench, and strike-slip faulting, which occurs several hundred km to the east of the trench and involves slip directed parallel to the trench. The December 26 earthquake occurred as the result of thrust-faulting. Approximately 1200 km of the plate boundary slipped and caused the earthquake – Earth’s crust vibration. The average displacement on the fault plane was about 15 meters.

The abrupt motion of a gigantic mass also influenced the whole Earth. Both USGS and NASA scientists calculated it. First, the masses on the equator moved closer to the Earth's center and the bulging at the equator decreased (by one part in 10 billion): the Earth became more spherical, and spins faster by 2.68 microseconds per day.

This is like a spinning skater drawing arms closer to the body resulting in a faster spin. This effect is common in astronomy, of course, in a clearly visible manner. This explains why the gaseous (Jupiter-like) planets, although giants, spin rapidly (Jupiter's day is <10 hours only): they consist of gases which are easily compressible, and therefore were subject to a much stronger compression than the slowly rotating Earth-like planets. We see the fastest rotation on neutron stars which experienced the strongest imaginable compression: from the diameter of about 2 million km to 20 km, a ratio of about 100,000 : 1 and therefore their spins are in the range of milliseconds.

Because the abruptly moved gigantic plate mass was located close to equator but on one side only (asymmetric "glitch"), it also shifted the Earth's rotational axis: mean North Pole moved about 2.5 centimeters (1 inch) in the direction of 134° east longitude (toward Guam in the Pacific Ocean). See the NASA report:

http://science.nasa.gov/headlines/y2005/10jan_earthquake.htm?list51473

Here is probably the best reference literature for the above subjects:

Carl D. MURRAY & Stanley F. DERMOTT, Solar System Dynamics; Cambridge University Press, 1999, 592 pages; ISBN 0-521-57597-4; especially:

Chapter 4, Tides, Rotation, and Shape (130 - 188 pp), written by Prof. Stanley Dermott.

http://ssdbook.maths.qmw.ac.uk/

How do Earthquakes Generate Tsunamis?

A tsunami (pronounced tsoo-nah-mee) is a wave train, or series of waves that form when the sea floor abruptly deforms and vertically displaces a body of overlying water. Earthquakes, landslides, volcanic eruptions, explosions, and even the impact of cosmic bodies such as meteorites, can generate tsunamis. Tsunamis can savagely attack coastlines, causing devastating property damage and loss of life. Tsunamis are unlike wind-generated waves, which many of us may have observed on a local lake or at a coastal beach, in that they are shallow-water waves with long periods & wavelengths. The wind-generated swell one sees at a California beach, for example, spawned by a storm out in the Pacific and rhythmically rolling in, one wave after another, might have a period of about 10 seconds and a wavelength of 150 m. A tsunami, on the other hand, can have a wavelength in excess of 100 km and period on the order of one hour. Tsunamis are only about a meter high at the most in the open ocean.

The best description of the tsunami physics, see:
Harald Ulrik SVERDRUP, Martin W. JOHNSON & Richard H. FLEMING: The Oceans, Their Physics, Chemistry, and General Biology; Prentice-Hall Inc., New York, 1942, 1087 pages (Chapter 14, Waves & Tides, p. 516 - 604, especially 542 - 545),

As a result of their long wavelengths, tsunamis behave as shallow-water waves. A wave becomes a shallow-water wave when the ratio between the water depth and its wavelength gets very small. Shallow-water waves move at a speed that is equal to the square root of the product of the acceleration of gravity (9.8 m/s/s) and the water depth - let's see what this implies: In the Pacific Ocean, where the typical water depth is about 4000 m, a tsunami travels at about 200 m/s, or over 700 km/hr. Because the rate at which a wave loses its energy is inversely related to its wavelength, tsunamis not only propagate at high speeds, they also travel great transoceanic distances with limited energy losses.

Tsunami fault photographed:                      http://www.geotimes.org/current/NN_sumatrafault.html

USGS Earthquake Hazard Reports:          http://earthquake.usgs.gov/eqinthenews/2004/usslav/

                                                                        http://neic.usgs.gov/neis/bulletin/neic_slav_ts.html

Physics of Tsunamis:            http://www.geophys.washington.edu/tsunami/general/physics/characteristics.html

 

Epicenter location: 250 km SSE of Banda Aceh, Sumatra, Indonesia
  310 km W of Medan, Sumatra, Indonesia
  1260 km SSW of BANGKOK, Thailand
  1605 km NW of JAKARTA, Java, Indonesia
Focus depth:  

30 km

 

 

Coordinates (GPS): N latitude 3.30°

  =    3° 18'

  E longitude 95.87°

  =  95° 52' 12"

 

Earthquake Date + Time: 26-DEC-04

07:58:53

local time
    00:58:53 UTC

Duration:

3 to 4 minutes subjectively

 

Rupture length 1200 km

along the Sunda trench

Maximum plates displacement 20 meters

of the overriding Burma plate

to the west-southwest

Dip of the subducting India plate 10° to the east-northeast at the focus; up to 45° at greater depth
Maximum sea floor displacement 10 meters  

 

Earthquake's Energy: 20 x 1017 Joules 475 megatons TNT 23,000 Hiroshima bombs

USGS calculations:

Length of day -2.676 microseconds >20 microseconds are measurable only
Polar motion excitation X -0.670 milliarcseconds due to the closeness to the equator, the total effect (0.82 milliarcseconds) is also negligible and hardly detectable

excitation Y

-0.475 milliarcseconds

Earthquake MAG 5.4 in South-West Germany Early Sunday, 5-DEC-04

There was a strong (MAG 5.4) earthquake in SW Germany early tonight:

Epicenter location: 5.45km ESE of Waldkirch
  14.2 km ESE of Emmendingen
  17.4 km NE  of Freiburg im Breisgau
Focus depth:   <12km within gneisses of Hochschwarzwald

 

Coordinates (GPS): N latitude 48°05' =48.08333°
  E longitude 8°02' = 8.03333°

 

Earthquake Date+Time: 5-DEC-04 02:52:36 MET
Arrival Time at my LAB:   02:53:45 MET
Earthquake Duration:   5 seconds  

 

Damages until 6-DEC-04, 13:38 Stuttgarter Nachrichten >10,000,000 EURO
   

http://www.stuttgarter-nachrichten.de/stn/page/detail.php/841609

Mostly gas pipelines, hospital,

The delay at my LAB was due to the propagation velocity of the Secondary seismic waves causing the main shaking. These S waves propagate within hard rocks (gneisses etc.) at a velocity of about 3.5 km/sec, whereas the P (Primary) waves are faster (about 7 km/sec), but usually are passing sites at longer distances such as my LAB (200 km).

Have you observed this earthquake?
I had been sitting at my PC at home and suddenly felt a strong wavy shaking, causing me a slight vertigo lasting about 5 seconds. My first impression was that my wife had lost her patience with me and was strongly shaking my spring chair while I was sitting at my PC. This spring chair even hit the other chair nearby and caused a ringing (clinking) sound. But my wife was quite innocent, quietly sleeping. It was an earthquake.

Geophysical / seismological studies:
Seismological Service, Feiburg im Breisgau: Mr. Wolfgang Brüstle
GeoCenter, Potsdam, Prof. Jochen Zschau

You may find maps, seismographic records and other info under:
http://www.seismo.ethz.ch/
http://www.seismo.ethz.ch/alarm/maps/KP200412050152.map.html
http://www.lgrb.uni-freiburg.de/lgrb/Fachbereiche/erdbebendienst/erdbebenmeldung/led_pool/images/karte041205.gif
http://earthquake.usgs.gov/recenteqsww/Quakes/usrraj.htm

http://edition.cnn.com/2004/WORLD/europe/12/05/germany.quake.ap/
http://www.gfz-potsdam.de/geofon/alerts/welcome.html
http://www.frsw.de/geologie.htm
 

Earth's Inner Core is Layered ...

Seismic evidence for an inner core transition zone by Xiaodong SONG, at Lamont-Doherty Earth Observatory, and Don V. HELMBERGER, at Seismological Laboratory, California Institute of Technology;
Science (AAAS, Washington D.C.), vol. 282, Nr. 5390/30 Oct. 98, p. 924 - 927 (short summary by Phil Szuromi, Ibiden, p. 841).

Reviewed in Geotimes, published by AGI (Alexandria VA), January 1999 issue, "News Notes": 
http://www.geotimes.org/current/newsnotes.html

See also:    Geophysical dynamics at the center of the Earth, by Raymond JEANLOZ and Barbara ROMANOWICZ, Physics Today, August 1997, pp. 22 - 27;    
Undestanding the Earth: When North Goes South:    http://www.psc.edu/science/glatzmaier.html/
showcases famous computer simulations of how the inner core gives rise to Earth's magnetic field.

This recent discovery is important to:

Currently, it is known that the Earth's core is composed of iron (probably of an iron and nickel alloy), that the outer core is liquid, and that the inner core is solid.

The liquid state is a special type of fluid state of matter. In solids, particles (atoms, ions, molecules) are so close to each other that they are fixed in regular positions, called crystal structure. In fluids, particles are more distant from each other so that they are not fixed but slide past each other. The particles of liquids attract each other so that they just slide at a constant distance from (in contact with) each other. Therefore, liquids maintain nearly the same volume and are almost incompressible.

The authors suggest that the inner core is composed of two distinct layers: the upper one completely isotropic, and the lower anisotropic.

Isotropy is a feature of a medium whereby all or certain medium properties are identical in all directions. Fluids are typically isotropic. Glass, being a stiff liquid, is also isotropic. In optics, the isotropy of a medium implies that the velocity of light is the same in all directions. We say that a medium has the same index of refraction in all directions. In the case of solids, only those crystallizing in the cubic (isometric) system are optically isometric. Solids crystallizing in other systems than cubic are optically anisometric. In seismic isotropy, the velocity of seismic waves is the same in all directions within the given medium. Anisotropic media have certain properties that change with the direction.

The thin isotropic outermost shell of the inner core probably consists of randomly oriented iron grains (of about 200 kilometer maximum thickness). It surrounds an anisotropic inner core of iron grains aligned along a north-south direction. Such a model can be used to test theories about the geodynamo, the cooling of the core, and the structural transition between the inner and outer core.