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    PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

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    HigherLove

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    PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:04 pm

    In accordance with Title 17 U.S.C. Section 107, this material is distributed without profit to those who have expressed a prior interest in receiving the included information for research and educational purposes.

    A roundup of plate tectonics from other threads, as well as a place to post new information.


    The World's Lithospheric Plates


    http://geology.about.com/library/bl/blplate_size_table.htm

    Plate Area (km2) Plate Area (km2)
    Pacific 103,300,000
    Scotia 1,600,000
    North American 75,900,000
    Burma microplate 1,100,000
    Eurasian 67,800,000
    Fiji microplates 1,100,000
    African 61,300,000
    Tonga microplate 960,000
    Antarctic 60,900,000
    Mariana microplate 360,000
    Australian 47,000,000
    Bismark microplate 300,000
    South American 43,600,000
    Juan de Fuca 250,000
    Somali 16,700,000
    Solomon microplate 250,000
    Nazca 15,600,000
    South Sandwich microplate 170,000
    Indian 11,900,000
    Easter microplate 130,000
    Philippine 5,500,000
    Juan Fernandez microplate 96,000
    Arabian 5,000,000
    Rivera microplate 73,000
    Caribbean 3,300,000
    Gorda microplate 70,000
    Cocos 2,900,000
    Explorer microplate 18,000


    Last edited by HigherLove on Thu Jul 21, 2011 7:34 pm; edited 1 time in total
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:08 pm

    Question: How Many Plates Are There?

    This question came up in email. It's not one that geologists ask—we're content to say "about a dozen major ones." But, my correspondent says, "The folks who write the standardized tests for our school district seem to think that the number of plates is an important fact." So you must have one right answer.

    Answer: I would object strenuously to this question because there are many right answers. A compilation by Peter Bird in 2003 listed 52 plates. The authoritative MORVEL model added six more in 2010. And they don't include a large number of smaller "microplates" and "blocks" named by regional researchers. But let's step back from that cliff and see how many plates really matter.

    The Earth's surface is about 500 million square kilometers, which is handy for the arithmetic. The seven largest plates (Pacific, North American, Eurasian, African, Antarctic, Australian and South American) add up to about 460 million, which is close enough to the whole thing. The seventh-largest plate, South America, is about 44 million, and the next largest is the Somali plate at 17 million, so seven seems like a natural cutoff.

    But then we get into the quibbles of schoolkids and teachers. "What about India?" they want to know. "I never heard of this Somali thing," they whine. Okay, to get to India (tenth-largest at 12 million) we have to include the Somali and Nazca plates. Because India, whatever its status as a plate, is important for reasons that are cultural and pedagogical—it's right in the middle of the map, and you can't teach about continental collisions or the Tibetan plateau without mentioning it. And those top-ten plates add up to more than 90 percent of the Earth, so that should end the discussion.

    But now that we've given in so far, we can't stop. In for a penny, in for a pound, as they used to say. Three more important places—the Philippines, Arabia and the Caribbean—come next, riding on their own little plates of 5.5, 5 and 3.3 million square kilometers respectively. But we can't stop at thirteen because only slightly smaller, at 2.9 million, is the Cocos plate, so that makes fourteen. The next-smallest (the Caroline microplate) is quite a bit smaller at 1.7 million, so I'm cutting things off at 14.

    Unfortunately, the whiners have another complaint: "Those aren't all on the map." The canonical plate map that I and everyone else uses doesn't match the list of the plates and doesn't match the plates I've just recited. The largest map I have doesn't point them all out. If anyone is reading this from the U.S. Geological Survey, would you please produce a new map?

    Another thing is that all the maps insist that the tiny Juan de Fuca "plate," actually just a microplate, belongs on the map with its name carefully pointed out, even though it ranks twenty-second in size. That's for pedagogical reasons, too, stemming from the history of science. The Juan de Fuca plate is where seafloor spreading was first convincingly mapped in the late 1950s, and that old map of seafloor "magnetic stripes" is still pulling its weight in the classroom.

    So please, teachers, don't make your students learn a number for the number of plates. There isn't just one. And geologists, if you haven't read Don Anderson's treatment of this question, see "How Many Plates?" which was published in the May 2002 Geology.

    http://geology.about.com/od/platetectonics/f/howmanyplates.htm
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:11 pm

    I live near the San Andreas Fault ("Strike-Slip" = side to side action). It goes off land and into the ocean just off of Cape Mendocino, which also places me near the Gorda and Juan de Fuca plates, which form part of the Cascadia Subduction Zone.

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/300px-Juan_de_fuca_plate.png" border="0" alt="Photobucket"></a>


    There are many local faults that are quite dangerous, inluding the Roger's Creek Fault, which is just the northern extension of the Hayward Fault Zone that runs through the east Bay Area, and just to the south.

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/2plates.jpg" border="0" alt="Photobucket"></a>

    In addition to dealing with the San Andreas nightmare and other strike-slip faults, Southern California is riddled with "Blind Thrust" faults (up and down, as with the Northridge quake).

    http://en.wikipedia.org/wiki/Fault_(geology)


    PLATE TECTONICS LINK


    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/img0061.jpg" border="0" alt="Photobucket"></a>


    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/534997631.jpg" border="0" alt="Photobucket"></a>

    Clear Lake Geology: Filed Trip Guide for Teachers

    http://lakeconews.com/content/view/15193/919/

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/201020State20fault20map20detail20-20Clear20Lake1.jpg" border="0" alt="Photobucket"></a>
    I live in the red area at the base of the volcano (all orange stripes) near the "175" sign. :op


    Can you see me waving from the fields?

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/AHLB36051.jpg" border="0" alt="Photobucket"></a>

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:14 pm

    Cape Mendocino


    http://en.wikipedia.org/wiki/Cape_Mendocino


    Where the San Andreas Fault goes slightly out to sea -


    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/tidesta10061.png" border="0" alt="Photobucket"></a>

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/MendocinoQuad1.jpg" border="0" alt="Photobucket"></a>

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/Cape-Mendocino101.jpg" border="0" alt="Photobucket"></a>

    King Range

    Cape Mendocino -

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:17 pm

    Note: Transform and strike-slip are the same thing.


    http://www.themistsofavalon.net/t2336-caribbean-plate-tension-increasing-7-seismic-swarms-erupting-across-the-planet#42946



    Eventually, this one may rear itself -


    clicking on graphic just takes you to my pics
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    HigherLove

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:22 pm

    Turkey is past due, and their big quakes tend to travel east to west, leaving Istanbul in the danger zone.

    http://en.wikipedia.org/wiki/Geology_of_Turkey








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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:24 pm

    http://volcano.oregonstate.edu/vwdocs/volc_images/southeast_asia/papua_new_guinea/tectonics.html

    Tectonic Setting and Volcanoes
    of Papua New Guinea, New Britain, and the Solomon Islands







    Tectonic microplates of the Melanesian region. Arrows show net plate motion relative to the Australian Plate. The volcanoes of New Britain are the result of subduction of the northward-migrating Solomon Sea Plate under the South Bismarck Plate. The volcanoes in the Solomon Islands are associated with the Solomon Sea Plate as it is subducted beneath the Pacific Plate. Two short spreading centers, one at the southeast margin of the Solomon Sea Plate and the other at the north edge of the South Bismarck Plate, influence volcanism at Kavachi (Solomon Islands) and the Admiralty Islands, respectively. Simplified from Hamilton (1979).


    The Solomon Islands, in the south-western Pacific Ocean, were struck by a powerful earthquake in the early hours of the 23 April 2011. The earthquake, which was reported by the United States Geological Survey as having a magnitude of 6.9, occurred offshore, around 50 miles from the town of Kirakira (USGS “Magnitude 6.9 Solomon islands”, earthquake.usgs.gov).

    The Earthquake of 23 April 2011

    At 6.9 magnitude, the earthquake was a significant one. It occurred at a depth of 8.9 miles underneath the ocean. Despite the magnitude of the earthquake (it was larger than that which struck Christchurch, in New Zealand, causing significant damage earlier in 2011) initial reports suggest that little damage was caused and at the time of writing no reports of injury or damage had been received (The Guardian online “Powerful earthquake strikes off Solomon Islands”, guardian.co.uk).

    Although submarine earthquakes of this magnitude may trigger tsunamis (depending on the nature of the earthquake) the National Oceanographic and Atmospheric Administration’s tsunami bulletin, issued in the aftermath of the earthquake, indicated that ‘a widespread destructive tsunami threat does not exist based on historical earthquake and tsunami data’ (NOAA tsunami bulletin, ptwc.weather.gov). No local tsunami bulletin was issued.



    Tectonic Setting of the Solomon Islands


    The Solomon Islands are part of a chain of islands which lie in the southwest of the Pacific Ocean, around 1300 miles northeast of the Australian city of Brisbane. The islands are the product of a complex series of tectonic-related events, their origin related to the submarine flood basalts of the Ontong-Java Plateau and to their location on the Pacific Ring of Fire (Petterson et al “Geological–tectonic framework of Solomon Islands, SW Pacific: crustal accretion and growth within an intra-oceanic setting” sciencedirect.com).


    It is the islands’ position on the margin of the Pacific Plate which provided the impetus for the earthquake of April 2011. At its simplest, the process can be explained as follows: that the north-eastward-moving Pacific Plate strikes the Australian Plate at an oblique angle and over-rides it. As the Australian Plate is forced downwards, friction is generated, building up to a point at which it is released in the form of an earthquake.

    In fact, the differential movements of the plates have generated a much more complex picture, with several smaller plates (microplates) forming as the two major plates meet. These include the Solomon Sea Plate, and it is along the boundary between this microplate and the Pacific Plate that the earthquake of 23 April occurred (Oregon State University “Tectonic Setting and Volcanoes of Papua New Guinea, New Britain, and the Solomon Islands” volcano.oregonstate.edu).



    Read more at Suite101: Magnitude 6.9 Earthquake Strikes Solomon Islands http://www.suite101.com/content/magnitude-69-earthquake-strikes-solomon-islands-a367379#ixzz1KQvIG1EO
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:25 pm



    Last edited by HigherLove on Thu May 05, 2011 3:30 pm; edited 1 time in total
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:26 pm

    Tonga Plate





    The Tonga Plate is a small southwest Pacific tectonic plate or microplate. It is centered at approximately 19° S. latitude and 173° E. longitude. The plate is an elongated plate oriented NNE - SSW and is a northward continuation of the Kermadec linear zone north of New Zealand. The plate is bounded on the east and north by the Pacific Plate, on the northwest by the Niuafo’ou microplate, on the west by the Australian plate and to the south by the Kermadec plate. The Tonga plate is subducting the Pacific plate along the Tonga Trench. This subduction turns into a transform fault boundary north of Tonga. An active rift or spreading center separates the Tonga from the Australian plate and the Niuafo’ou microplate to the west. The Tonga plate is seismically very active and is rotating clockwise.

    MORE: http://whatonearth.olehnielsen.dk/plates/tonga.asp
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:27 pm

    <iframe title="YouTube video player" width="480" height="390" src="https://www.youtube.com/embed/qQ9Mw_rtDng" frameborder="0" allowfullscreen></iframe>
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:27 pm

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 3:29 pm

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  lindabaker on Thu May 05, 2011 3:52 pm

    Troy, that was a significant amount of research and editing Just For Us. I wanted to let you know that I appreciate the time that you are putting into this thread. Thanks, Linda
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  lindabaker on Thu May 05, 2011 4:03 pm

    For anyone in the Mists regarding the US: which do you think might release first, the Carribean plate, the New Madrid, or California, or the Pacific NW? Something is warning me about the Carribean, first. I keep thinking about Mississippi for some reason. I don't like making predictions, but, do the Gulf coast residents have a tsunami warning system in place?

    We are all moving now, all of the plates are "loose" in a sense. I keep visualizing a soft landing, and a re-alignment of the poles in a good, kind, and gentle way. I really don't think we need any more lessons in the US, as life "on the ground" is more difficult than what is being shown on the news. The economic changes are truly making people understand how we must help each other, and that was the theme of our nation from the very beginning. Kindness to strangers is a way of life here. We will all be okay, but shew, I'm thinking it's not necessary to "quake up" any more folks. To the earth: You Have Our Attention! You know that we know that your power is immense, fabulous, and we love you. Okay, so you have shown us enough. We get it! Peace!

    Linda
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 6:45 pm

    lindabaker wrote:Troy, that was a significant amount of research and editing Just For Us. I wanted to let you know that I appreciate the time that you are putting into this thread. Thanks, Linda

    It is truly my pleasure.

    And thank YOU!

    Double Thumbs Up
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 6:49 pm

    lindabaker wrote: I keep thinking about Mississippi for some reason. I don't like making predictions, but, do the Gulf coast residents have a tsunami warning system in place?
    Linda

    I found this, so far:

    Tsunami warning system to be tested on Atlantic, Gulf coasts in April (2010)

    The tsunami warning announcement to be broadcast at 8 a.m. on April 2 is no April Fools Day joke.

    It's a first-ever test of a new Atlantic and Gulf of Mexico tsunami warning system designed to cue coastal communities of the potential danger of huge waves caused by earthquakes.

    Co-sponsored by the National Oceanic and Atmospheric Administration and the U.S. National Tsunami Hazard Mitigation Program, the test also will include Canadian Atlantic Provinces and U.S. Caribbean Territories and Commonwealths.

    Participating emergency management agencies along the East and Gulf coasts will conduct workshops and tabletop exercises centered on a tsunami warning, while several Puerto Rico communities will conduct evacuation drills. Participants will evaluate the effectiveness of their preparedness plans following the exercises.

    The United States warning system was updated in 2005 after an Indian Ocean tsunami struck coastlines in the Indian Ocean with little or no warning, killing about 230,000 people in a number of countries.

    "The 2004 Indian Ocean tsunami raised awareness about the urgent need to be prepared," said Jack Hayes, director of NOAA's National Weather Service, in a news release announcing the drill.

    The chances of a tsunami hitting the Louisiana Gulf Coast are slim, based on recent research into Caribbean Ocean earthquake zones. Few of the known geologic faults in the Caribbean that might cause a tsunami are aligned in ways that would send waves into the Gulf of Mexico. However, there are several known faults in the Gulf itself that have a remote chance of causing the huge waves.


    http://www.nola.com/news/index.ssf/2009/03/tsunami_warning_system_to_be_t.html
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 10:14 pm

    TECTONIC FORCES

    The Origin and the Mechanics of the Forces Responsible for Tectonic Plate Movements
    By Robert Maurer


    This treatise examines in detail both the limitations of the heated current circulation model as the driving force ('slab-pull' and 'ridge- push') for tectonic plate movement, and the considerations of the newly developed concept of tectonic movements being a function of unbalanced centrigugal forces acting on the Earth's crust. http://www.tectonic-forces.org/index.html

    SIMPLIFIED VERSION: http://www.tectonic-forces.org/simplified.htm

    Abstract

    It is postulated that tectonic plate movements can be explained as a function of the unbalanced centripetal forces generated by the eccentricity of the centre of mass of a rotating unbalanced planetary body. Using this approach, the magnitude of the forces available to create and sustain tectonic movements, orogenic activity and the coefficient of friction at the crust / mantle interface are estimated. The magnitude and direction of these unbalanced centripetal forces also suggest that the currently accepted hypothesis of 'Slab Pull' by convection currents and 'Sea Floor Spreading' at ocean ridges by H Hess18 in 1962 as the driving forces for tectonic movement now have a passive rather than an active role in tectonic plate movements. To date 'inertial' or centripetal / centrifugal based forces have been considered as being negligible in the context of the forces associated with plate movements. It is now suggested that the complex circulatory system of mass convection currents within the mantle are an inevitable consequence of the continental movements by these unbalanced forces as distinct from being responsible for tectonic activity. In this context the term 'Continental Force–- Push' will be introduced into the vocabulary of tectonic movements.

    The term 'Centripetal force' is understood to be the inward force on an object moving in a curved path.

    _________________________________________

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 05, 2011 11:46 pm

    THE SCOTIA PLATE
    Plate Tectonics, Spreading Ridges, and Triple Junctions


    http://whatonearth.olehnielsen.dk/plates/scotia.asp


    The Scotia Plate is an oceanic tectonic plate bordering the South American Plate on the north, the South Sandwich Plate to the east, and the Antarctic Plate on the south and west.

    The north and south boundaries of the plate are transform fault boundaries. At the eastern margin the Scotia has a spreading boundary between it and the small South Sandwich Plate. The South American Plate is subducting under east side of the South Sandwich Plate, which is thought to have brought about its separation from the Scotia Plate, starting as backarc spreading.

    The western boundary with the Antarctic plate is a complex and rather ill-defined boundary.

    The plate is named after the Scotia sea, under which it lies.

    http://en.wikipedia.org/wiki/Scotia_Plate

    http://en.wikipedia.org/wiki/Backarc_spreading

    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/FileSubZonejpg.jpg" border="0" width="600"></a>


    The islands of Japan were separated from mainland Asia by back-arc spreading
    <a href="http://illiweb.com/fa/pbucket.gif" target="_blank"><img src="https://2img.net/h/i835.photobucket.com/albums/zz272/DSummerMan65/300px-Japan_separationpng.png" border="0" width="600"></a>


    http://en.wikipedia.org/wiki/Mid_ocean_ridge





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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Thu May 12, 2011 5:33 am

    Understanding the Lorca, Spain May 11 2011 earthquake


    The southeastern Spain earthquake of 11 May, 2011, occurred within the plate boundary region that separates the Eurasia and Africa (Nubia) plates. At the longitude of the earthquake, the Africa plate moves NW with respect to the Eurasia plate with a velocity of 6 mm/yr.



    Earthquakes in different parts of the plate-boundary region separating Africa and Eurasia may occur as the result of strike-slip or normal faulting, in addition to the reverse/thrust faulting that is expected as the most direct consequence of the convergence of two major plates. The diversity of faulting styles over the plate-boundary region may reflect the motions of crustal blocks that are situated within the broader plate-boundary zone and that move slowly relative to one another to accommodate the NW/SE convergence of the major plates.


    The epicenter of the 11 May earthquake is situated near a major fault, the Alhama de Murcia fault. However, significant field work in the epicentral region of the earthquake will be necessary to confidently determine if the earthquake occurred on a segment of the Alhama de Murcia fault or on a nearby fault.

    In recent decades, the larger shallow-focus shocks of southeastern Spain have had magnitudes of about 5.

    Shocks of this size occurred near the epicenter of the 11 May earthquake in February 1999 and August 2002. The distributions of damage associated with several shocks that occurred before the twentieth century imply that these shocks had magnitudes in the 6.5-7 range.

    Iberia and the Mahgreb also experience occasional deep-focus earthquakes of magnitude greater than 6 that occur at depths of over 600 km in lithosphere that was subducted along the plate boundary millions of years ago.






    http://earthquake-report.com/2011/05/12/understanding-the-lorca-spain-may-11-2011-earthquake/
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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Tue May 17, 2011 7:23 pm

    Oddball Bahamas isle hints at seismic activity

    As other islands are slowly sinking, this 'stable' one is going against grain



    All the islands in the Bahamas were thought to be slowly sinking, but now scientists find one quirky isle going against the crowd.

    This anomaly suggests the area may be less seismically stable than previously thought.

    Scientists focused on the small island of Mayaguana in the southeast Bahamas, which measures about 33 by 7 miles. They noticed shallow banks of rocks called marine carbonates above ground that are usually present dozens of feet below the surface on the other Bahamian islands. These deposits are about 39 feet thick, span more than 17 million years of geologic history and are only found on the isle's northern coast.

    The unusual placement on these rocks gave researchers insights into the tectonic processes going on below the Caribbean.

    "It took us about three years to process all the data and come up with a coherent story," said researcher Pascal Kindler, a geologist at the University of Geneva in Switzerland.

    These findings suggest Mayaguana rose and tilted toward the south about 500,000 years ago. Such activity is likely related to faults in the Earth's crust near the island. In fact, its perfectly linear northern coastline might actually correspond to one such crack.

    "Finding geological evidence of recent tectonic activity in a region that was up to now considered as stable is probably the most exciting, surprising aspect of our results," Kindler told OurAmazingPlanet.

    Activity along faults generates earthquakes. However, the Mayaguana faults are not as active as those near Haiti, and the probability of a major quake and tsunami in this area fortunately remains low.

    Further study of these rocks on Mayaguana could provide a wealth of data on everything from climate change to geological activity along the margins of continental plates. In addition, "we are planning to investigate other geologically unexplored islands in the southeast Bahamas — Little and Great Inagua, Crooked and Acklins Islands — that might show features similar to those found on Mayaguana," Kindler said.

    The scientists detailed their findings online May 4 in the journal Geology.


    http://www.msnbc.msn.com/id/43066940/ns/technology_and_science-science/t/oddball-bahamas-isle-hints-seismic-activity?gt1=43001
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    HigherLove

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Mon Jun 06, 2011 8:27 am

    HigherLove wrote:http://www.themistsofavalon.net/t2162p315-earth-changes-2011-daily-updates#47677

    (Thanks, Carol).

    The Karen




    Carol wrote:June 6, 2011 – CHRISTCHURCH, Nz – A 5.0 (5.5) earthquake has struck outside the city of Christchurch on the south island of New Zealand once again. The quake was incredibly shallow; registering at 3.8 km on maps according to the USGS.

    June 5, 2011 – ANTARCTICA – A 6.3 magnitude earthquake has been recorded near MacQuarie Island just north of Antarctica. The quake represents some of the seismic dynamism we noted earlier in the Southern hemisphere. A 5.4 earthquake was also recorded in Maule, Chile. The Fiji region was also shaken by a 5.8 and a 5.1 earthquake.


    Eruption or lithospheric fracturing: have earthchanges taken dangerous new turn?
    June 5, 2011 – SANTIAGO, Chile – One of the volcanoes in the Caulle Cordon of southern Chile erupted violently Saturday, billowing smoke and ash high into the sky and prompting more than 3,500 people living nearby to evacuate. There were no reports of injuries. Authorities initially said the Puyehue volcano was involved, but later said the eruption was occurring about 2 1/2 miles (four kilometers) from that peak. A rift more than six miles (10 kilometers) long and three miles (five kilometers) across was torn in the earth’s crust, officials said Saturday night. Authorities had put the area on alert Saturday morning after a flurry of earthquakes, and the eruption began in the afternoon. The National Emergency Office said it recorded an average of 230 tremors an hour. About 600 people were evacuated when the first alert went up and hundreds more left their homes after the eruption began. Rodrigo Ubilla, Chile’s undersecretary of labor, said some people near the volcano had decided not to leave their homes because they didn’t want to abandon their animals. Wind carried ash across the Andes to the Argentine tourist town of San Carlos de Bariloche, which had to close its airport. Officials warned residents of the Bariloche area to take precautions against a possible prolonged ashfall. They urged people to stock up on food and water and to stay home. The eruption is nearly 620 miles (1,000 kilometers) south of Chile’s national capital, Santiago. – Yahoo News


    Commentary: The lithosphere vents heat to keep the planet’s crust from basically fracturing and splitting apart. In 2010, we saw the most volcanic eruptions in recorded history and still the thermal depressurization threshold of the planet’s land surface was not reached, as new volcanoes are now erupting in 2011 that did not erupt in 2010. This is telling us a most important piece of information- there are not enough terrestrial volcanoes on land to equilibrate the geological pressures now unsettling the ground. Since the volcanoes under the ocean are pressurized by ocean depths- in my opinion, this increases the likelihood more and more with each eruption, that two things will now begin happening- lithospheric fracture-venting on land, similar to what’s occurring under the ocean with hydrothermal vents or much larger-scale eruptions becomes necessary to stop this runaway process. We may be years away from seeing one or more super-volcanic eruptions take place if this is a linear entropic process as I hypothesize it is.

    If this report of a massive rift is correct from Chilean authorities, then the earthquake swarm in Neuquen, Argentina could have been a prelude to this fracture event: “Earth is a pressurized ball of magma…if you keep seismically shaking the Earth like a bottle of soda, its structural integrity will eventually become compromised and it will start to fracture like an egg. In this case, the fracturing will be thermal dissipation by hyper-volcanism, mega-thrust earthquakes, and greater tectonic boundary agitation around volcanic arcs and subduction zones.” -The Extinction Protocol, page 564
    http://theextinctionprotocol.wordpress.com/

    CO2 emissions rise three times higher than safe level at Indonesia’s Mt. Dieng volcano
    June 5, 2011 – INDONESIA – Poisonous gases spewing from Mount Dieng surpassed levels deemed safe for humans on Sunday. The level of carbon dioxide concentration measured in the air at Timbang, one of Mount Dieng’s six craters, is two times higher than what is considered safe, Sutopo Purwo Nugroho, a spokesman for the National Disaster Mitigation Agency, said. On Sunday morning, the crater released thick clouds that spread approximately 100 meters towards the south and the main road connecting Wonosobo and Banjarnegara districts. Five new earthquake detectors had been installed around Mount Dieng to monitor activities of three of its craters- Kepakisan, Karangetah and Pasorenan. The detectors are vital in not only detecting ground movement, but also toxic gases released from below. Locals have been instructed to remain in evacuation shelters and no one is permitted within a 1 kilometer radius of the crater. There are over 1000 evacuees currently living in shelters in Batur, Pejawaran, Wanayasa and Karangkobar. –Jakarta Globe
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    HigherLove

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Sun Jul 10, 2011 11:39 am

    http://www.themistsofavalon.net/n2954-tilt-south-pacific-seismic-crisis-moving-towards-geological-catastrophism

    Boundaries of the Australian Plate

    The Australian plate is a product of the seafloor spreading-induced fragmentation of the ancient supercontinent Gondwana. The Australian plate used to be a part of the larger Indo-Australian plate. This plate contains the continents of Australia, New Zealand, Indonesia, and Papua New Guinea.

    The southeastern border of the Australian plate is a convergent boundary with the Pacific plate, although complexities occur near New Zealand. The Pacific plate subducts under the Australian plate to form the Tonga and Kermadec Trenches, and the parallel Tonga and Kermadec island arcs, north of New Zealand. New Zealand straddles this edge, and south of the North Island the tectonic boundary is a transform fault. In the central South Island plate motion is manifested as a predominantly strike-slip movement along the Alpine Fault. In the southwestern part of the South Island, relative plate motion is accommodated by oblique subduction of the Australian plate, and consequent deformation of the overriding Pacific plate inland of the trench, which has produced the Southern Alps of New Zealand.

    https://wiki.carleton.edu/display/tectonics/Australian+plate


    From Post 9: The Tonga Trench is just north of the Kermadec Trench.

    HigherLove wrote:
    Tonga Plate





    The Tonga Plate is a small southwest Pacific tectonic plate or microplate. It is centered at approximately 19° S. latitude and 173° E. longitude. The plate is an elongated plate oriented NNE - SSW and is a northward continuation of the Kermadec linear zone north of New Zealand. The plate is bounded on the east and north by the Pacific Plate, on the northwest by the Niuafo’ou microplate, on the west by the Australian plate and to the south by the Kermadec plate. The Tonga plate is subducting the Pacific plate along the Tonga Trench. This subduction turns into a transform fault boundary north of Tonga. An active rift or spreading center separates the Tonga from the Australian plate and the Niuafo’ou microplate to the west. The Tonga plate is seismically very active and is rotating clockwise.

    MORE: http://whatonearth.olehnielsen.dk/plates/tonga.asp
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    HigherLove

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    Re: PLATE TECTONICS / EARTH'S LITHOSPHERIC PLATES

    Post  HigherLove on Sun Jul 10, 2011 6:10 pm

    THE KERMADEC ISLANDS





    The Kermadec Islands consist of 13 islands and islets, located between 800km and 1000km north-east of New Zealand. Macauley and Raoul account for over 95% of the land. This chapter examines their origins. The islands are volcanoes of the Kermadec Ridge, pushed up by the Pacific Plate which subducts into the deep Kermadec Trench.

    Location

    This map shows New Zealand in relation to Australia. It also shows NZ's outlying islands and its Exclusive Economic Zone (EEZ). The Kermadec islands lie NE of New Zealand, roughly in the direction of NZ's main axis. Their distances apart and their distance to the North Island happen to be of the right size to add a considerable area of EEZ. As can be seen, Norfolk Island which is administered by Australia, lies roughly at the same latitude of about 30ºS.

    The detailed map of the sea bottom, shown below (Map courtesy NIWA) reveals that the sea bottom has major features such as the 8km deep Kermadec Trench on right, and next to it the Kermadec Ridge, which provides the volcanic activity to bring the Kermadec Islands to the surface. further back the Colville Ridge, which is of older date. In the middle the South Fiji Basin, a large area of deep ocean floor of 3-4km deep. To the left the Three Kings Ridge, also formed much earlier than the others, and finally the Norfolk Ridge with the submarine volcano of Norfolk Island, which has a very large plateau on it. At the very bottom of the chart, the northern tip of the North Island can be seen.

    Please take note of the location of the Kermadecs, in order to locate it at world maps used further down this chapter (and the chapter on ecology), on which they are not marked.




    http://www.seafriends.org.nz/issues/res/kermadec/kermgeo.htm

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