highest peaks on earth?

Discussion in 'Earth Science' started by EmptyForceOfChi, Nov 29, 2005.

  1. valich Registered Senior Member

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    3,501
    I never said that ALL magma "is molten mantle," but when a plume comes up from the outer core of the Earth, the intense heat melts part of the mantle and becomes part of it, just as plate tectonic activity does in the upper lithosphere.

    Again: "I never said that magma "does not have to be mantle derived"....there are also straight magma plumes that come straight up out of the outer core through the lithosphere that produce hot spots. The term "hot spot" is quite ambiguous in geology, but nevertheless, a hot spot can be formed from a straight plume from the outer core or from curculating convection currents in the mantle or through any number of means of plate tectonic actions that generate pressure and heat."

    Magma is derived directly from the outer core through plumes, through convection currents in the mantle, or through any number of plate tectonic activities that occur near the surface that result in pressure that liquifies various compositional constituents of rock.
     
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  3. Ophiolite Valued Senior Member

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    No magma comes from the outer core. Check your facts. I repeat no magma comes from the outer core.
     
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  5. valich Registered Senior Member

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    Many geolists attribute hot spots and volcanos to plumes arising vertically straight-up directly from the outer core. This is the predominant theory: but still hotly debated. In any case, what has been this ridiculous two-page fuss about magma not being molten mantle (-or molten crust)? And all these useless mudslinging posts above: challenges, snipey little comments, condescending remarks - void of any content. This is an embarrassment to sciforum and a regression of progress in science. The content of this forum has gone far adrift from the subject of the original posting. My own posting here belongs on a new thread called "What are Plumes: the Debate" or "Are Plumes the Origin of Hot Spots and some Volcanos?"

    The fact that magma near the Earth's surface does not consist of 90% iron and some nickel is proof in itself that that molten mantle material does not directly flow straight-up as a fluid from the outer core. If there are such straight-up plumes, they would be more like segregated molten chambers, or vertical heat convection currents, but by the time the heat is convected to the surface, the magma is dilluted molten mantle. I am very sceptical of all this, even though it was what I was taught many moons ago. Therefore, I am more inclined to agree with you. Nevertheless, the majority views:

    "Plume: an upwelling of molten material from the Earth's mantle."
    Source: http://www.thefreedictionary.com/plume

    "Plume theory: The fluid mechanics of low-Reynolds-number plumes is well understood. A mantle starting plume is predicted to consist of a large spherical head followed by a small tail. When it reaches the top of its ascent the head flattens to form a disk with a diameter twice that of the spherical head. Plume heads have been proposed to be responsible for Earth's major flood basalts and plume tails for aseismic ridges and island chains that connect the flood basalt to the current position of the hot spot. Plume theory makes the following testable predictions:

    1) plume heads have a surface expression up to 2,500 km across,
    2) lood volcanism is preceded by 1000 ± 500 m of uplift,
    3) temperatures within the plume are 100 to 300 ?C higher than the adjacent mantle,
    4) plume tails extend to the core-mantle boundary.

    Source: http://www.agu.org/meetings/cc05gcall.html

    "A mantle plume is an upwelling of anomalously hot rock in the Earth's (or another planet's) mantle. Mantle plumes are thought to be the cause of volcanic centers known as hotspots and probably also have caused flood basalts. In 1971, geophysicist, W. Jason Morgan proposed the theory of mantle plumes. In this theory, convection in the mantle slowly transports heat from the core to the Earth's surface. Plumes of hotter-than-average material rise through the mantle till it reaches the Earth's crust where it causes a hotspot. The plumes originate at a thermal boundary layer at the core-mantle boundary. Also, a "superplume" is the term for a larger-scale plume. It is usually defined as a plume that has a diameter of at least 1500-3000 km by the time the plume head spreads at the base of the lithosphere."
    http://en.wikipedia.org/wiki/Magma_plume

    Melting anomalies can result from upwelling jets – plumes...The usual explanation for melting anomalies is that they result from active hot upwellings from a deep thermal boundary layer. http://www.mantleplumes.org/PlumeDLA.html

    Hypothetical View of Outer Core to Upper Lithoshere Plumes:

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    "Plumes are thought to originate very deep in the Earth at the core-mantle boundary for the larger ones and at a depth of about 600 km deep for the smaller ones - but they seem to be related to the breakup of continents (rifting), so there is some influence from global plate tectonic processes."

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    "This may represent a typical pattern of plume distribution at any period of geological time....The plumes are proposed to be richer in lighter elements and hotter than the surrounding mantle. As they rise, magma (liquid rock) is generated by partial melting of the plume material. The magma is injected into the lithosphere and erupted onto the Earth's surface to form huge basalt lava flows."
    Source: http://www.geolsoc.org.uk/template.cfm?name=fbasalts

    "All upward movement of mantle material is confined to about 20 plumes, each plume a few hundred kilometers in diameter, rising from the core–mantle boundary. The plume effectively burns a hole through the overlying crustal plate .. and a volcano results." Source: “Volcanoes,” by P. Francis, 1976.

    "A mantle plume is a localised, roughly axisymmetric upwelling of buoyant rock, originating from a boundary layer deep within the Earth...Rock, plus melt at higher levels. Unspecified – 670 km or core-mantle boundary are likely candidates."
    Source: “Plumes and Plumage,” by Andy Saunders, Symposium of the Herdman Society, Dept. Earth Sciences, Liverpool University, March 2004.

    "Plume: an upward flow of hot material from the Earth's mantle into the crust.”
    Source: "Geology: An Introduction to Physical Geology," by Chernicoff, C. and R. Venkatakrishnan, 1995, p. 593.

    "Mantle Plume: a buoyant mass of hot mantle material that rises to the base of the lithosphere. Mantle plumes commonly produce volcanic activity and structural deformation in the central part of lithospheric plates."
    Source: "The Earth's Dynamic Systems," W.K. Hamblin, 1989, p. 555.

    "Plume: a persistent pipelike body of hot material moving upward from the Earth's mantle into the crust. Its surface expression may be a hot spot.”
    Source: "Dictionary of Geological Terms," by Bates R.L. and J.A. Jackson 1984, p. 391.

    "Plume: A column of magma rising from the lower mantle and spreading sideways on reaching the base of the lithosphere, proposed as an explanation of the motion of lithospheric plates and of sites of volcanic activity away from plate margins"
    Source: Oxford Educational Dictionary

    "A solid-state, narrow upwelling current in the mantle with a diameter of the order of 100 km and originating from a hot, low-density boundary layer located either above the seismic discontinuity at 660 km depth or near the core-mantle boundary at 2,900 km depth." Source: Hoffmann, 1997.

    "A cactolith is an irregular intrusive igneous body of obscurely cactuslike form, more or less confined to a horizontal zone and appearing to consist of irregularly related and possibly distorted branching and anastamosing dikes that fed a laccolith.
    Source: " Glossary of Geology," Erik Lundin, 23rd December, 2003

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    http://www.mantleplumes.org/DefinitionOfAPlume.html
     
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  7. Ophiolite Valued Senior Member

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    Exactly. The magma does not come from the core. Not all magmas come from the mantle. I accept the above as a convoluted retraction of your erroneous statements. Thank you.
     
    Last edited: Dec 29, 2005
  8. valich Registered Senior Member

    Messages:
    3,501
    I did not make any erroneous statements, therefore this is no "convoluted retraction" of anything that I said. It is an attempt to make clear what other's seem to have taken out of context or in bits and pieces of a sentence.

    For example, in one of your last posts on the previous page you quoted me as saying: "If magma was strictly molten Earth's core, then it would consist almost entirely of iron and nickel." Again, notice the little tiny, weeny word "If" there?

    This last post was in responce to Invert's usual codescending, belittling remarks, and doodah's further misleading, out-of-context again, void-of-content postings:

    “ Originally Posted by valich
    Yes, of course, magma has different compositions. Hot spots in magma chambers in the lithosphere (upper layer of the mantle) melt surrounding rock with all sorts of mineral composition.”

    You finally admit that magma does not have to be mantle derived- which has been my whole point. Please realize that most volcanic/magmatic systems do not require hot spots, especially ones originating at the core-mantle boundary.

    "Originally Posted by valich
    Magma is molten mantle.

    Then again doodah posts:

    "Originally posted by Valich
    "Is there something about geology that you'd like to ask me that I can help you with? I'd be more than happy too if I can? ”

    In your own words, then, Valich, is all magma derived from the mantle (i.e. "Magma is molten mantle")?

    A simple question."

    Now where did I ever say "in your own words Valich" that "ALL magma is derived from the mantle."?

    You guys are just too much. My post was in reply to doodah's request for a reply to a "A simple question."

    Furthermore, as I stated, is there something about geology that you'd like to ask me that I can help you with? If so, I'd be more than happy to do so if I can? This thread has gone way off the brink. Do you or do you not need any help in answering a geology question? You guys certainly need help in understanding how to read. And how to take things in context. And how to learn without turning a forum into a childish immature mudslinging session that brings the entire integrity of sciforum down.

    If you've got something educational to post then post it. But from the start: so many abusive, foul-language swearing. Those are not words from a Scientific Intelligent Community.

    When we invite a guest lecturer in for a seminar, we may disagree, but to use abusive and foul language like you guys have done? Do you think that after word of that type of abusive behavior got around that ANY scientist would dare want to patronize our university to give a lecturer? Of course not!
     
  9. Ophiolite Valued Senior Member

    Messages:
    9,232
    Again, I appreciate the difficulties you are labouring under working in a foreign language. It would therefore be more appropriate if you were to accept guidance from those who are native speakers.
    The statement 'magma is molten mantle' indicates a clear and absolute eqivalence. A one on one mapping. You did not say 'some magma is molten mantle', which would have been a valid and uncontroversial statement. Instead you said 'magma is molten mantle'. That is an invalid statement. That is what you have been criticised for.
    And your persistent refusal to acknowledge when you have made an error. And this ongoing, mind-numbing, intellectually stullifying, time wasting, infantile, unscientific, dragging out to the end of infinity, counter argument and counter accusation. Grow up little man. I will patronise anyone who acts with the singleminded childishness that you display on so many of your posts. As I have pointed out to you repeatedly you have a simple solution. Stop with the nonsense why don't you.
     
  10. valich Registered Senior Member

    Messages:
    3,501
    As you can see from my long scientificially cited posting above, MAGMA DOES COME FROM THE OUTER CORE. It circulates through the boundaries, as is clearly shown in the diagrams. This is the commonly held view today within the geological scientific community, but as far as coming up as a direct plume, this view is hotly debated.

    I just annihilated your as usual sarcastic codescending post that was strictly designed to attack me, but your so pigheaded that you'll never admit it. Convection currents circulate. What do you think that there is some kind of impenetrable iron curtain at each and every boundary that prevents chemical compositional exchange?

    Magma is molten mantle. In tectonics we include the crust as part of the lithosphere. The lithosphere is the top half of the mantle. What are you denying?
     
  11. Ophiolite Valued Senior Member

    Messages:
    9,232
    No it does not.
    Not it is not.
    At last: a point of agreement.

    Not only chemical, but physical. Tell us vallich, educate us poor simpletons in the wonders of the Earth. For the past 4.5 billion years the iron and various siderophile elements have been extracting themselves from the mantle and moving towards the centre of the Earth where they formed the core. Most of this movement occured early in the Earth's history, but it has never stopped. What is the wonderful mechansism that has suddenly reveresed this trend?

    The lithosphere is not the top half of the mantle, you twat. The lithosphere includes the top part of the mantle. They are not equivalent. Therefore, as noted above:
    Some magma is molten mantle: True
    Magma is molten mantle: False

    Even you should be able to understand the difference.

    Now stop wasting space and time, and confusing casual readers who don't know any better. Such behaviour is really vile, vallich. You claim to want to educate yourself and others, yet you pursue this policy of obfuscation and confusion. It is intellectually dishonest and really quite unattractive. Stop it.

    Oh, I know what I can do now. A trick I learnt from you.

    Locked.
     
  12. valich Registered Senior Member

    Messages:
    3,501
    What are you talking about??? I am native United States Citizen with five certificates, four degrees, and fluent in three languages. Where did you ever get the idea that I was "labouring under working in a foreign language"? Or that speaking a foreign language was "labouring"? This is what I mean about you. You just make these things up out of nothing. Suddenly something off-beat, weird, and imaginary get's posted, for the sole reason of attacking me, out of thin air. Do you just dream this up in your head as part of some kind of twisted wharped sidekick game? Just what the hell are you talking about???

    English is my native language. I was born in Ohio, went to Ohio University for eight years, Cleveland State Unuiverasity, Boise State University, Arizona State University, University of Arizona, Northern Arizona University, Feng Chia University, Tamkang University, Tamsui Oxford University, Xiamen University, and three community colleges. Before that I ran my own Automotive Repair Center after graduating from the General Motors Institute of Training with five ASE (Automotive Service Excellence) technical certificates. Before that I worked as a motorcycle mechanic for Harley-Davidson for five-years. And before that, during high school and part-time afterwards, I managed a restaurant. So you see, I worked hard to work my way up the ranks to get and learn what I know today. And believe me, I've made plenty of blunderous mistakes along the way. But I learned by them and moved on. I think I've been around.

    Have you ever apologized for needlessly swearing at me and using foul-mouthed language? The ultimate sign of childish immaturity? Hell no! You just want someone to argue with because you're childisd - just bored, I guess? - you've just got nothing better to do with your time. Get a life!

    I said that "Magma is Molten Mantle." In tectonic terminology, everything above the outer core is the mantle, including the Earth's crust. So what else is there? The terminology differs when you're talking about chemical composition layers, structural geology, or plate tectonics; but we were discussing tectonic activities underlying orogeny. Let's see if YOU retract your statement - as you never do: Oh High Supreme God of Geology, His Holiness in a Can of Rocks, that we are ALL supposed to bow down to and pray in awe and reverance! Isn't that exactly what you meant when I first posted an answer to a question on a geology forum for someone. Remember oh crustal Ophiolite of the sea? You immediately - almost instinctively -screamed out, "Alright valich. You're in MY territory now!"

    What a spoiled-rotten brat!

    Let's wait to see if you retract your statement that "magma does not come from the outer core."

    The inner core is almost entirely iron.

    The outer core is 80% iron with small amounts of nickel, sulfur, magnesium, and platinum-group elements that have a chemical gradient (like the mantle does too) and gives off radioactive decay.

    The lower mantle is 34% iron, 17% silicon, 16% magnesium, and 1.6% nickel and is a mushy plastic-like rock with pockets of molten rock. The lower down you go into the mantle, the hotter it becomes, and the greater the concentrations of iron.

    It is unreasonable to think that there would not be any exchange of molten material between the liquid outer core and the lower molten mantle pockets.

    "CORE-MANTLE EXCHANGE: core-mantle exchange subsequent to core formation include many different forms, with some reactions taking place at the CMB that have little or no manifestation in the geochemical record. Peridotites show <10% variation in Mg/Ni and <15% variation Mn/Fe for samples of all ages. Archean to modern basalts and komatiites show <20% variation in P/Nd. Collectively these lithophile to siderophile ratios limits to about <1% by mass any secular exchange between the core and mantle. Core-mantle exchange based on Os isotope systematics is on a much smaller scale by at least 2 orders of magnitude, and perhaps this is only relative to the mass of the upwelling plume. http://mahi.ucsd.edu/cathy/SEDI2002/ABST/SEDI1-2.html

    Again, If there are any questions that you have about geology, time-permitting, I am more than happy to try and help you answer them, but you are just so blatantly and irritatingly obnoxious that you are impossible to communicate with in an educational intelligent way. Therefore, unless you change your obnoxious irritating attitude, then stop antagonizing me by stalking me on these forums - posting condescending, belittling, smart ass little comments immediately after I post. That's stalking!
     
  13. Ophiolite Valued Senior Member

    Messages:
    9,232
    From your clear inability to understand written English.
    I never needlessly swore at you. On each occasion I have berated you it was necessary as part of an attempt to break through your self-righteous shell. Ineffective, yes. I concede that. Apologise? Show an ounce of humility and I'll desist, but I'll not apologise for calling you a little twat, when your actions define you exactly as such.

    No it isn't. And this is precisely where my dialogue with you ends. From this point forward, when you post an inaccurate statement I shall post a disclaimer to the effect that the post by you has been made by a person who believes "In tectonic terminology, everything above the outer core is the mantle, including the Earth's crust."
    That should protect all but the dumbest from falling into the trap of believing your persistent misinterpretations.

    Dear casual reader, be aware of two important points:
    The mantle lies below the crust. It has done so for billions of years.
    Vallich lies above the crust. He has done so for as long as I have known him.
     
  14. UnderWhelmed Registered Senior Member

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    147
    This is not true...

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    Sincerely,

    Causual Rreader
     
  15. valich Registered Senior Member

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    3,501
  16. valich Registered Senior Member

    Messages:
    3,501
    "Magma is Molten Mantle." In tectonic terminology, everything above the outer core is the mantle, including the Earth's crust.

    UnderWhelmed states: "This is not true...

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    Sincerely, Causual Rreader."

    Dear UnderWhelmed: No, you just don't post something and then call yourself a "Casual Reader." First, learn how to spell. Next, state what you mean by authoritatively stating "This is not true." What are you trying to say then?

    What is YOUR definition of magma? The mantle is made of compositional layers of rocks. Magma is molten rock: Magma is molten mantle. Explain.
     
  17. Ophiolite Valued Senior Member

    Messages:
    9,232
    For example:
    Way to go kid.
     
  18. valich Registered Senior Member

    Messages:
    3,501
    Again, using tectonic terminology, the mantle is all rock compositional layers above the outer core:

    "The mantle is a dense, hot layer of semi-solid rock."
    http://pubs.usgs.gov/publications/text/inside.html

    "Mantle rock consists of olivines, different pyroxenes and other mafic minerals."
    http://en.wikipedia.org/wiki/Mantle_(geology)

    "Magma is molten rock beneath the surface of the earth."
    www.hull.ac.uk/geogmods/html/glossary.html

    "Magma is naturally occurring molten or paritally molten rock material, generated within the Earth."
    csd.unl.edu/general/glossary-letter.asp

    Magma is molten rock containing liquids, crystals, and dissolved gases that forms within the upper part of the Earth's mantle and crust. When erupted onto the Earth's surface, it is called lava."
    interactive2.usgs.gov/learningweb/textonly/teachers/volcanoes_guide_glossary.htm

    What part of the above definitions do you need help with in understanding?
     
  19. Ophiolite Valued Senior Member

    Messages:
    9,232
    The mantle lies below the crust.
    Not all magmas originate in the mantle. Some originate by partial melting of the crust.

    Vallich, do you really not understand this very simple point? Despite your great education are you really that thick? None of your links support your statement. They all support or are consistent with mine.

    I tell you what, if you can get guthrie, or BillyT, or doodah, or underwhelmed, or Skinwalker, to tell me I am mistaken on this point I'll publicly apologise and never post a refutation of any of your posts in the future. pm them now. Ask them to come and stidy this thread and offer their opinions. I'll be bound by their opinions. What do you have to lose? You've already lost your credibility. Go on, take the risk. Have the courage of your convictions. Or, are they all fools too? Like me?
     
  20. UnderWhelmed Registered Senior Member

    Messages:
    147
    According to this picture (note that the crust is the dark portion at the top of the picture and that the bracket that encloses the mantle stops just below that part):

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    This statement is false:

    Both of which were posted by you...

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  21. UnderWhelmed Registered Senior Member

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    147
    By the way; I totally agree with most of your point’s valich, but I also think that Ophiolite is right in regards to what your disputing.
     
  22. mouse can't sing, can't dance Registered Senior Member

    Messages:
    671
    Valich,

    I'll admit that my knowledge in this field is severly limited, but given the picture UnderWhelmed linked (which, as he/she noted, was copied from your own post), I have to agree with both UnderWhelmed and Ophiolite.

    Sincerely,

    Another Casual Reader
     
  23. doodah Registered Senior Member

    Messages:
    79
    This is quite a broad definition of the term "hot spot", which is o.k., but is certainly not the conventional definition used by earth scientists.

    Congratulations, you've finally broadened your definition of "magma" to include the crust as a source, not just the mantle.

    Ophiolite and Underwhelmed are right- the Earth has three distinct layers- the core, the mantle and the crust. The crust is not part of the mantle. Magma can be generated by partial melting of the crust without involving molten mantle material- and in fact, this is common in areas of mantle convection subsidence (subduction zones).

    I have to admit, though, that Ophiolite's challenge was tempting...

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    (just for the fun of it)
     

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