text:
Talk:Human/Archive 5

id:
cool, the article has just been translated into Indonesian! dab (ᛏ) 13:12, 15 Dec 2004 (UTC)

Spirituality and religion
What's with the very long section on spirituality and religion? Shouldn't this go under articles such as spirituality or religion? - Montréalais 20:33, 20 Dec 2004 (UTC)

 * Funny you should ask. If you look at the archived talk section, you will find a VERY long discussion of that very point.  The final consensus was that, since the article aims to answer the question "What is a human being?", then it should include definitions that have spiritual elements or that arise in religious contexts.  JHCC 20:55, 20 Dec 2004 (UTC)

 * That's fair enough, but I don't see why it needs to be an entire section with several long-winded paragraphs. - Montréalais 04:03, 21 Dec 2004 (UTC)

 * Feel free to propose improvements. Tom - Talk 07:29, Dec 21, 2004 (UTC)

I took a recent look at the section in question, and I really like what you have done with it, JHCC. The whole article is really nice. And that picture of the little girls is great! Thanks and attaboy, JHCC. That said, the overall organization of the article hasn't quite been revised to be completely consistent. We have the Biology (really the Humans per Biology) section and the Spirituality and Religion (really Humans per Spirituality and Religion) section. But then we have the The Individual section, which is a little confusing once you get the purpose of the previous two sections. Finally society and self-reflection. It all is a little confusing. Maybe we can talk about it and play around with it a bit. Tom - Talk 21:34, Dec 20, 2004 (UTC)

===Biology=== ===Spirituality and religion=== ===The individual=== ===Society=== ===Self-reflection===

A difficulty with organizing the article is that there are widely divergent views on what is quintessentially human, and yet there is broad agreement on much that is human. The top of the article tries to address what is quintessentially human from two distinct perspectives, but then without any segue, the last three sections go more broad and universal. I personally cannot see a way to improve the organization other than to rename the first two sections to make their purpose more clear to visitors like Montréalais. An attempt below. Tom - Talk 21:49, Dec 20, 2004 (UTC)

===The biological human=== ===The spiritual human=== ===The individual=== ===Society=== ===Self-reflection===

How about these following. - UtherSRG 13:33, Dec 21, 2004 (UTC) ===Human biology=== ===Human spirituality=== ===Human individuality=== ===Human society=== ===Humans and self-reflection===

Or by reduction and restoration... - UtherSRG 13:33, Dec 21, 2004 (UTC) ===Biology=== ===Sprituality and religion=== ===Individuality=== ===Society=== ===Self-reflection===

Nothing wrong with the above except that they don't reflect the direction of the intro. I am okay with leaving the article as it is, but there is a distinct difference of meaning between Human biology and The biological human, between Human spirituality and The spiritual human. Remember that there are whole areas of the encyclopedia dedicated to human biology and human spirituality; this article can only contribute by discussing the human in biology and in spirituality. I again re-iterate that it is not the spirituality and biology in human that are the organizing framework of this article, it is the human in biological and spiritual terms. Tom - Talk 15:09, Dec 21, 2004 (UTC)

 * Ok. Read my last suggestions as if they all ended with "of humans" (or something similar that works. Does that scan better and more in accordance with what we're working towards? - UtherSRG 15:18, Dec 21, 2004 (UTC)

 * Hmmm. Now I am embarrassed for being difficult.  Unfortunately, "Biology of humans" and "Spirituality and religion of humans" essentially mean "Human biology" and "Human spirituality and religion".  Either of those incarnations of that meaning essentially say, "This section is about the biological (or spiritual) component of humans."  But there are significant points of view that would take exception to the factual accuracy of either the biology section or the spirituality section except for the fact that both sections say, "This is what humans most importantly are from a certain perspective."  Some religionists would take exception to the neutrality of saying "Humans are great apes."  Some atheists would take exception to the neutrality of saying, "Humans are living spirits temporarily incarnated for transcendent purposes."  It is false advertising and it invites disputes about the contenct of the sections when we label them Human biology and Human Spirituality.  Should the religionist complain that the Human biology section says he is a great ape?  No, he shouldn't; the section is about what the human is from a biological point of view.  Should the atheist complain that the Human spirituality section says he is a child of God?  No, he shouldn't; the section is about what humans are from a spiritual point of view. Tom - Talk 19:02, Dec 21, 2004 (UTC)

So the expanded titles would be: ===The essential human from a biological perspective=== ===The essential human from a spiritual perspective=== ===The essential human from an individualist perspective=== ===The essential human from a cultural perspective=== ===The essential human from other significant perspectives=== Tom - Talk 19:02, Dec 21, 2004 (UTC)

I think we're getting closer, but I think those headings are overly verbose. I also think we're picking nits. Some reductions follow. - UtherSRG 19:39, Dec 21, 2004 (UTC)

These could be pluralized (perspectives), or be explicitly labeled as PsOV. ===Biological perspective== ===Spiritual perspective=== ===Individualist perspective=== ===Cultural perspective=== ===Other perspectives=== UtherSRG 19:39, Dec 21, 2004 (UTC)

Another possibility. ===Biological essense=== ===Spiritual essense=== ===Individualist essense=== ===Cultural essense=== ===Other essenses=== UtherSRG 19:39, Dec 21, 2004 (UTC)

Finally, I think the biology and religion sections are of greater importance to maintaining a balanced NPOV. The importance or purpose or origination of the other sections relies significantly on the individuals beliefs about the first two. Perhaps their headings should be of one form, while the other three take a different form. - UtherSRG 19:39, Dec 21, 2004 (UTC)

 * Great! Further, I might suggest simply:

===Biological=== ===Spiritual=== ===Individualist=== ===Cultural=== ===Other perspectives=== Tom - Talk 23:05, Dec 21, 2004 (UTC)

 * Is it absolutely necessary to have parallel formation in each of these headings? The section on the Individual (which in my opinion should be scrapped and its material be divided between the other sections) is not a definition of Humanity from an "Individualist perspective" (whatever that might mean), but a description of certain aspects of the human individual.
 * I would suggest:

===Human self-reflection=== ===Human biology=== ===Spiritual and religious definitions of humanity=== ===Human society and culture===
 * Moving "Self-reflection" first gives us a foundation for the descriptions which follow, although the material in the second to last paragraph could be moved to elsewhere.

 * A key part of this whole endevour is remembering that this article is not a catchall for every aspect of humanity; it is here to answer the question "What is a human being? or more particularly, "How is 'Human' defined?" Discourses on the origins of monotheism, while fascinating, are less important in this context than, say, comparing the idea that humans were created ex nihilo by an omnipotent and benevolent deity (as in your basic Judeo-Christian understanding) with the idea that one deity created the material world and another created humanity out of that matter (as in classical Greek and Roman mythology).  JHCC 20:35, 21 Dec 2004 (UTC)

 * I very strongly agree with this. Very well put. Tom - Talk 23:10, Dec 21, 2004 (UTC)

 * I've done a trial edit on the lines I laid out above. Feel free to edit or even revert, but I think it's a good first step in cutting out a lot of the dead wood.  JHCC 22:18, 21 Dec 2004 (UTC)

 * I'm okay with it. And with the vision you expressed above, I have full confidence in the direction you are headed. Tom - Talk 23:10, Dec 21, 2004 (UTC)

I'm not. What had started as primarily a biology-focused article became a well balanced article with biology and spirituality/religion both significantly high in the order (with biology just above spirituality/religion as they are the PsOV most opposed to each other). Now both biology and spirituality/religion have been reduced in primacy with the elevation of self-reflection. I prefer self-reflection to be below the other two. - UtherSRG 23:28, Dec 21, 2004 (UTC)

 * Good points. Tom - Talk 15:42, Dec 22, 2004 (UTC)

 * UtherSRG, thank you for your bluntness; very good point you raise. I'm going to remove the entire "Self-Reflection" section, as it duplicates material from the "Human Self-Reflection" article without adding anything significant.  That should restore the balance, as well as keep the article from getting too big.  If there is anything that we want to keep from the "Self-Reflection" section, we can edit it back in somewhere.  JHCC 02:56, 22 Dec 2004 (UTC)

 * OK. Tom - Talk 15:42, Dec 22, 2004 (UTC)

 * JHCC, please. The Human self-reflection article was exported from this article, as a concession that the topic should not take up too much space here. You cannot use that as an argument to remove the section completely. Also, regarding monotheism etc., I did try to keep the historical bits as short as possible. The reason they are present is that some people will insist on mentioning God as an answer to the question "what is human". Now I insist that this article is about entire human race, i.e. including all human lives from ca. 2M years ago. The monotheism part is meant to convey that for some time this was (and still is) a prevalent pov, but that the vast majority of historical humans probably thought along very different lines. I don't mind some pruning and editing at all, but keep in mind that the article content was balanced over months of discussion, and thes discussions are likely to be repeated, with the same arguments, and the same positions, if you start deciding that some parts are not needed. dab (ᛏ) 09:03, 22 Dec 2004 (UTC)

 * Some of this bothers me. JHCC covers my concerns well below. Tom - Talk 15:42, Dec 22, 2004 (UTC)

 * Answering your two points:
 * The SR section is good stuff, but it clogs the article. Logically, it should be just after the intro, as it provides a framework for the Biology/Spirituality/Culture sections that follow.  Unfortunately, this throws off the balance of article, as UtherSRG pointed out above.  Having it anywhere else makes it look like it's just been stuck in as filler.  Personally, I think my solution was a good compromise, but I'm more than willing to consider other possibilities.
 * Regarding historical development of religions, I maintain that this should only be included insofar as it relates to human self-definition. So, for example, to note in the section on animism that this is the world-view for which we have the earliest evidence or in the section on monotheism that the practice of monotheism appears to date back approximately three millennia, that's fine.  If what we are looking for is historical perspective on the distribution of belief over human history, great.  However, I do not think that it is as relevant that the earliest documentation of monotheism is "the heresy of Akhenaton" as it is that an anamist and a polytheist may have very different concepts of what it means to be a human.  Even within monotheism, there may be huge differences of opinion: a Christian Scientist may believe that the entire physical world (including the human body) is just an illusion, while a Roman Catholic may believe that the body is real, but corrupted by sin.  I maintain that we should concentrate on concisely expounding these different answers to "what is a human" rather than on tangential (if interesting) discourses on the development of religions.  JHCC 14:51, 22 Dec 2004 (UTC)

 * Ditto. Tom - Talk 15:42, Dec 22, 2004 (UTC)

[A month later] This section is confused again. I am going to try to retrieve an acceptable old wording. I am also going to be bold and try changing some headings to clarify what is going on in this article to try to head off entropic edits. Tom Haws 16:27, Feb 2, 2005 (UTC)

Position of the Taxobox
In my opinion, the Taxobox is in the wrong place; it should not be at the top of the Human page. It should be in the Biology section--because Biology and the Taxobox are not the defining qualities of "Human." The defining quality of human is the intergenerational transmission of technology and culture part.
 * Suffice it to say, this is a case of beating a long-dead horse. →Raul654 07:53, Dec 22, 2004 (UTC)
 * Sado-necro-bestiality? - UtherSRG 13:02, Dec 22, 2004 (UTC)
 * the current solution is not graven in stone, but I think we would want at least like a dozen signatures to re-open the topic. dab (ᛏ) 08:56, 22 Dec 2004 (UTC)
 * I don't know if I should comment on this or not. Ah why not. I think that if random fols coming to this page expect to see the taxobox up at the top, then it should be there. Obviously Sam Spade did. If we move it back down to the biology section, that may suffice as long as the biology section stays near the top of the article. - UtherSRG 13:02, Dec 22, 2004 (UTC)
 * is fols a typo for folks or for fools? :p You know, some random folks will expect it here, and some other random folks will expect it there. We will have people commenting on it no matter where we put it. This was discussed in extenso, and I don't think there is any 'perfect' solution to it, and I also think the present compromise is probably the optimal solution. dab (ᛏ) 13:08, 22 Dec 2004 (UTC)
 * I'll let folks foolishly choose at random what my meaning was. *grins* But otherwise, I suppose I agree with you. - UtherSRG 13:26, Dec 22, 2004 (UTC)
 * I agree with dab, keep it where it was. Not perfect, maybe, but a workable compromise.  JHCC 14:51, 22 Dec 2004 (UTC)

Whoa! I guess I missed something. Raul654 said the taxobox was at the top, but it isn't. I guess Sam Spade moved it to the top for a moment before it got returned to it's consensus location in the biology section, right? It sounds like we are all in agreement then; it is where it has to be, in the Biological (see section titles discussion above) section. Did I follow correctly? Tom - Talk 15:47, Dec 22, 2004 (UTC)

'major editing'
well, why is the 'Individual' section gone? Can we have it back please? this was 'major editing' indeed. I argue we need both a 'Society' and an 'Individual' section, as these are complementary concepts. dab (ᛏ) 15:21, 11 Jan 2005 (UTC)
 * I agree. A proper description of "human" requires both a description of the 1) individual and the 2) society--because many different societies are possible from the same collection of individuals.  Similarly, in a proper description of "water," it is necessary to describe both the characteristics of the water 1) molecule and 2) mole of water--because many different collective phenomena in the mole of water are possible from the same collection of water molecules.  Different collective phenomena in the mole of water from the same collection of water molecules would include: solid, liquid, gas, supercooling, superheating, triple point, and meniscus.  Furthermore, the "individual" section of the Human page should be separate from the "biology" section--because different "individual" phenomena are possible from the same "biological" unit.  Similarly, a proper description of "computer" requires a distinction between "hardware" and "software"--because entirely different behavior manifests in the same "computer" unit with different "software."  That is, the "individual" section of the Human page describes phenomena that are not determined by the "biology" but by the vast cultural evolution that is programmed into the individual's "software" by learning.  We have all been through this before, 8))) I know, but it is buried in the Archives to this page.  And the editor that made the "major edit" was careless in not thinking through what "human" really is and did not consult the archives of this TalkPage. For all of the above reasons, the "individual" section should be restored with the content pulled back to its proper place.  For example, the section "Psyche and consciousness" should be pulled back into the "individual" section--because "Psyche and consciousness" are products of cultural evolution--not biological evolution.  ---Rednblu | Talk 19:18, 11 Jan 2005 (UTC)
 * well, can we first restore it as it was, and then argue about how to change it? I agree it should represent the individual's pov, as opposed to biology's 'bird's eye'. JHCC was involved in the archived discussions, though, so he was aware of the considerations that went into it. dab (ᛏ) 19:44, 11 Jan 2005 (UTC)

so, will anybody object if I resurrect the 'Individual' section? dab (ᛏ) 11:50, 1 Feb 2005 (UTC)

Wikiproject Tree of Life specification must be changed
I reverted the position of the taxobox according to the extended discussion and voting on this TalkPage. Apparently, the Wikiproject Tree of Life specification is wrong and should be corrected. I will get around to initiating that discussion on the "Tree of Life" TalkPage--eventually. ---Rednblu | Talk 21:06, 15 Jan 2005 (UTC)

 * What do you mean, the ToL specification is "wrong"? Reverting the movement of the taxobox is fine, but could you not be so oblique here? Is it really so much effort to make a little bit of sense, especially since there's no readily apparent consensus that the taxobox specification is wrong over on WP:TOL. grendel|khan 22:26, 2005 Jan 15 (UTC)
 * Sorry. I was in a hurry and did not explain myself clearly.  I already made the correction to the Table of Life specification in this edit. ---Rednblu | Talk 00:52, 16 Jan 2005 (UTC)

 * Why would the taxobox style have to change specially for humans? The information about biological classification that the taxobox provides is still just as valid as it is for any other species. I don't see where the 'extended discussion and voting' you refer to has anything to say about the ToL spec being 'wrong'---which is, so far as I can tell, an opinion held by you and just you, from what I can see on the ToL page. grendel|khan 01:12, 2005 Jan 16 (UTC)

If this discussion is about the taxobox position, yes, that was decided very slowly and deliberately with a lot of input from a lot of people. There would certainly have to be a large group assembled again to discuss the matter if we were to consider having it preside over the article again. The taxobox is indeed just as valid for Homo sapiens as it it for any other species. I only beg that those who were not here for the previous discussion to consider the NPOV principle of ownership of words. No single group owns the term Human, and if significant and major points of view hold that biology is not primarily definitive of humans, then it is probably appropriate to keep the taxobox out of the intro. At least this is how I understand the outcome of the previous discussion and its interpretation in light of the established policies. In case you were not here for that discussion, I recall for you that one weakly favored proposal was to have a separate article Homo sapiens or such about the biological human with the taxobox at the top. Tom H. 15:49, Jan 17, 2005 (UTC)

comp sci definition
the comp-sci definition is missing from the page. T

he comp-sci definition is: A man is a computer that can pass the turing test

 * wrong. this is a definition of intelligence, not of humanity. dab (ᛏ) 13:03, 12 Feb 2005 (UTC)

Revert
Why is this article so weird? Why is there a picture of 2 girls at the top instead of a txobox? And why is

 * Philosophers define human beings straightforwardly as bipeds without feathers, for humans are standing on their two feet, but, unlike most birds, they don't possess feathers. Hence a human being is not a chicken.

in the intro? I think my version was way better. Comments? (Sam Spade | talk | contributions) 21:40, 14 Feb 2005 (UTC)

Probably you will get general agreement about the oddness of the "philosopher's view" "a human is not a chicken". The article does seem to be getting untidy. And I apologize because I may have regretfully reverted when I should have carefully reconstructed the consensus form from your edit. What would need to be discussed would be the image and taxobox. In general, the article is at a point now that I think it could benefit from a little rewording and editing to keep it focused on answering the question "what is a human?" I just edited the Birth and death section in a way that I think kept the content. Tom Haws 21:49, Feb 14, 2005 (UTC)

 * Sounds good. So why don't you want the taxobox at the top, like it is on pretty much every other article about an animal? I don't like the anthrocentric and "little girl-centric" feel it gives. Cheers, (Sam Spade | talk | contributions) 21:55, 14 Feb 2005 (UTC)

Me again. Here is how I understand the standing agreement on the focus of the article: Tom Haws See above and in archives too. Note that most articles have a nice, flattering mug shot at the top. The little girls was voted best of proposals. But of course the whole thing can be discussed again. Tom Haws 21:58, Feb 14, 2005 (UTC)
 * What is a Human? Depends whom you ask. (Little girls are the best we found as a nice illustration of humans.) Tom Haws
 * Some hold a biological answer pre-eminent, and this is what they say about humans. (Taxobox here) Tom Haws
 * Some hold a spiritual answer pre-eminent, and they say this. Tom Haws
 * Some answer primarily in cultural terms, and here is how. Tom Haws

 * HM. I'm a bit confused. Lots of people say lots of things, and that which can be verified as coming from an expert source can be mentioned in the article, but Homo sapiens links here. You seem to be suggesting it shouldn't. (Sam Spade | talk | contributions) 22:17, 14 Feb 2005 (UTC)

the article has really been deteriorating. I moved back to the carefully balanced, consensus approved intro. If people want to tweak the intro, they should discuss. The birth and death section should be part of "individual". dab (ᛏ) 22:24, 14 Feb 2005 (UTC)

 * Right, dab. Thumbs up. Tom Haws 23:31, Feb 14, 2005 (UTC)

title: Talk:Human/Archive 5


text:
Wikipedia:Requests for comment/LIGerasimova

In order to remain listed at Requests for comment, at least two people need to show that they tried to resolve a dispute with this user and have failed. This must involve the same dispute, not different disputes. The persons complaining must provide evidence of their efforts, and each of them must certify it by signing this page with ~. If this does not happen within 48 hours of the creation of this dispute page (which was: 21:16, Jan 27, 2005 (UTC)), the page will be deleted. The current date and time is:, 29 July 2024 (UTC).

Statement of the dispute
LIGerasimova is engaged in a continuous and deliberate personal attacks and false accusations on Tabib. She spends most of her time attacking other editors (esp. Tabib) in often crude personal terms and provoking conflicts between users.

Description
User LIGerasimova suddenly appeared in Wikipedia on Feb 9, 2005 in the midst of hot disputes between Tabib and user Pantherarosa over the content of the Safavids page. From the very first day LIGerasimova distinguished herself by aggressively attacking other editors and accusing them in POV, promotion of "Turkish propaganda" and establishing a "Turkish mafia". Interestingly, user LIGerasimova claimed that she was a neutral third party and came to the discussion after Tabib's call for mediation. However, after viewing LIGerasimova's contribution log it is hardly convincing, which makes one think that she has some hidden intentions. See, Tabib's talkpage for details. Moreover, according to LIGerasimova's contribution log, she spent almost all of her time attacking other editors. Her attacks and insults continued even though other editors largely ignored her attacks and avoided responding to her groundless accusations.

For details see, user Tabib's talkpage and to a lesser degree Safavids talkpage.

 * Thanks for twisting facts again, and again (ad nauseam??) Instead of whining into everybody's ears, stic to ethical conduct!--LIGerasimova 12:31, 15 Feb 2005 (UTC)

Since recently, LIGerasimova waged another attack on User:Tabib in Nagorno-Karabakh talkpage. This recent atack demonstrates that LIGerasimova di not give up her/his/ disruptive actions.

Evidence of disputed behavior
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 * Personal insults based on editor's national/ethnic background
 * False accusations on creating a "Turkish mafia"
 * False accusations of vandalism
 * Labelling other user "sock-puppet"

Applicable policies

 * No personal attacks
 * Civility
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 * Attempt at warning user of disruptive behavior, , ,
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 * --Tabib 15:49, 15 Feb 2005 (UTC)

2. --Ulvi I. 23:32, 15 Feb 2005 (UTC)

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{User Luba Ivanovna Gerasimova is well known to me. She is a sincere, resolute and just person, deeply concerned with ethical conduct. As she observed unethical and insincere activities on the part of user Tabib, she confronted him with facts in a clear but correct manner. She was met with vile language by user Tabib in return, did however not respond in the same manner. It is ridiculous to describe her as a "vandal" just because she points a finger on slezy business going on (User Tabib trying to rigg opinion with the help of user Deli Eshek, as documented on the latter's talk page. User Tabib hastened to eradicate traces of his foul play, was immediately caught by MS. Gerasimova, whom he showered with abuse again). Please refer to the contribution logs of User Tabib and Ms. Gerasimova}

Kiramtu Kunettabib 19:36, 2 Mar 2005 (UTC)

 * For purposes of clarity, pls, see my reply here--Tabib 20:34, Mar 2, 2005 (UTC)

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text:
Vector projection

The vector projection (also known as the vector component or vector resolution) of a vector $a$ on (or onto) a nonzero vector $b$ is the orthogonal projection of $a$ onto a straight line parallel to $b$. The projection of $a$ onto $b$ is often written as $$\operatorname{proj}_\mathbf{b} \mathbf{a}$$ or $a_{∥b}$.

The vector component or vector resolute of $a$ perpendicular to $b$, sometimes also called the vector rejection of $a$ from $b$ (denoted $$\operatorname{oproj}_{\mathbf{b}} \mathbf{a}$$ or $a_{⊥b}$), is the orthogonal projection of $a$ onto the plane (or, in general, hyperplane) that is orthogonal to $b$. Since both $$\operatorname{proj}_{\mathbf{b}} \mathbf{a}$$ and $$\operatorname{oproj}_{\mathbf{b}} \mathbf{a}$$ are vectors, and their sum is equal to $a$, the rejection of $a$ from $b$ is given by: $$\operatorname{oproj}_{\mathbf{b}} \mathbf{a} = \mathbf{a} - \operatorname{proj}_{\mathbf{b}} \mathbf{a}.$$

To simplify notation, this article defines $$\mathbf{a}_1 := \operatorname{proj}_{\mathbf{b}} \mathbf{a}$$ and $$\mathbf{a}_2 := \operatorname{oproj}_{\mathbf{b}} \mathbf{a}.$$ Thus, the vector $$\mathbf{a}_1$$ is parallel to $$\mathbf{b},$$ the vector $$\mathbf{a}_2$$ is orthogonal to $$\mathbf{b},$$ and $$\mathbf{a} = \mathbf{a}_1 + \mathbf{a}_2.$$

The projection of $a$ onto $b$ can be decomposed into a direction and a scalar magnitude by writing it as $$\mathbf{a}_1 = a_1\mathbf{\hat b}$$ where $$a_1$$ is a scalar, called the scalar projection of $a$ onto $b$, and $90° < θ ≤ 180°$ is the unit vector in the direction of $a_{1}$. The scalar projection is defined as $$a_1 = \left\|\mathbf{a}\right\|\cos\theta = \mathbf{a}\cdot\mathbf{\hat b}$$ where the operator ⋅ denotes a dot product, ‖a‖ is the length of $b$, and θ is the angle between $a$ and $b$. The scalar projection is equal in absolute value to the length of the vector projection, with a minus sign if the direction of the projection is opposite to the direction of $a$, that is, if the angle between the vectors is more than 90 degrees.

The vector projection can be calculated using the dot product of $$\mathbf{a}$$ and $$\mathbf{b}$$ as: $$\operatorname{proj}_{\mathbf{b}} \mathbf{a} = \left(\mathbf{a} \cdot \mathbf{\hat b}\right) \mathbf{\hat b} = \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{b}\right\| } \frac {\mathbf{b}} {\left\|\mathbf{b}\right\|} = \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{b}\right\|^2}{\mathbf{b}} = \frac {\mathbf{a} \cdot \mathbf{b}} {\mathbf{b} \cdot \mathbf{b}}{\mathbf{b}} ~ .$$

Notation
This article uses the convention that vectors are denoted in a bold font (e.g. $b$), and scalars are written in normal font (e.g. a1).

The dot product of vectors $b̂$ and $b$ is written as $$\mathbf{a}\cdot\mathbf{b}$$, the norm of $a$ is written ‖a‖, the angle between $a$ and $b$ is denoted θ.

Scalar projection
The scalar projection of $b$ on $a_{1}$ is a scalar equal to $$ a_1 = \left\|\mathbf{a}\right\| \cos \theta, $$ where θ is the angle between $a$ and $b$.

A scalar projection can be used as a scale factor to compute the corresponding vector projection.

Vector projection
The vector projection of $a$ on $a$ is a vector whose magnitude is the scalar projection of $b$ on $a$ with the same direction as $b$. Namely, it is defined as $$\mathbf{a}_1 = a_1 \mathbf{\hat b} = (\left\|\mathbf{a}\right\| \cos \theta) \mathbf{\hat b}$$ where $$a_1$$ is the corresponding scalar projection, as defined above, and $$\mathbf{\hat b}$$ is the unit vector with the same direction as $a$: $$\mathbf{\hat b} = \frac {\mathbf{b}} {\left\|\mathbf{b}\right\|}$$

Vector rejection
By definition, the vector rejection of $b$ on $a$ is: $$\mathbf{a}_2 = \mathbf{a} - \mathbf{a}_1$$

Hence, $$\mathbf{a}_2 = \mathbf{a} - \left(\left\|\mathbf{a}\right\| \cos \theta\right) \mathbf{\hat b}$$

Definitions in terms of a and b
When $θ$ is not known, the cosine of $θ$ can be computed in terms of $b$ and $a$, by the following property of the dot product $b$ $$ \mathbf{a} \cdot \mathbf{b} = \left\|\mathbf{a}\right\| \left\|\mathbf{b}\right\| \cos \theta$$

Scalar projection
By the above-mentioned property of the dot product, the definition of the scalar projection becomes: $$a_1 = \left\|\mathbf{a}\right\| \cos \theta = \frac {\mathbf{a} \cdot \mathbf{b}} { \left\|\mathbf{b}\right\|}.$$

In two dimensions, this becomes $$a_1 = \frac {\mathbf{a}_x \mathbf{b}_x + \mathbf{a}_y \mathbf{b}_y} {\left\|\mathbf{b}\right\|}.$$

Vector projection
Similarly, the definition of the vector projection of $b$ onto $b$ becomes: $$\mathbf{a}_1 = a_1 \mathbf{\hat b} = \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{b}\right\| } \frac {\mathbf{b}} {\left\|\mathbf{b}\right\|},$$ which is equivalent to either $$\mathbf{a}_1 = \left(\mathbf{a} \cdot \mathbf{\hat b}\right) \mathbf{\hat b},$$ or $$\mathbf{a}_1 = \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{b}\right\|^2}{\mathbf{b}} = \frac {\mathbf{a} \cdot \mathbf{b}} {\mathbf{b} \cdot \mathbf{b}}{\mathbf{b}} ~ .$$

Scalar rejection
In two dimensions, the scalar rejection is equivalent to the projection of $a$ onto $$\mathbf{b}^\perp = \begin{pmatrix}-\mathbf{b}_y & \mathbf{b}_x\end{pmatrix}$$, which is $$\mathbf{b} = \begin{pmatrix}\mathbf{b}_x & \mathbf{b}_y\end{pmatrix}$$ rotated 90° to the left. Hence, $$a_2 = \left\|\mathbf{a}\right\| \sin \theta = \frac {\mathbf{a} \cdot \mathbf{b}^\perp} {\left\|\mathbf{b}\right\|} = \frac {\mathbf{a}_y \mathbf{b}_x - \mathbf{a}_x \mathbf{b}_y} {\left\|\mathbf{b}\right\| }.$$

Such a dot product is called the "perp dot product."

Vector rejection
By definition, $$\mathbf{a}_2 = \mathbf{a} - \mathbf{a}_1 $$

Hence, $$\mathbf{a}_2 = \mathbf{a} - \frac {\mathbf{a} \cdot \mathbf{b}} {\mathbf{b} \cdot \mathbf{b}}{\mathbf{b}}.$$

By using the Scalar rejection using the perp dot product this gives

$$\mathbf{a}_2 = \frac{\mathbf{a}\cdot\mathbf{b}^\perp}{\mathbf{b}\cdot\mathbf{b}}\mathbf{b}^\perp$$

Scalar projection
The scalar projection $b$ on $a$ is a scalar which has a negative sign if 90 degrees < θ ≤ 180 degrees. It coincides with the length $b$ of the vector projection if the angle is smaller than 90°. More exactly:
 * $a ⋅ b$ if $a$,
 * $b$ if $a$.

Vector projection
The vector projection of $a$ on $b$ is a vector $a$ which is either null or parallel to $b$. More exactly:
 * $‖c‖$ if $a_{1} = ‖a_{1}‖$,
 * $0° ≤ θ ≤ 90°$ and $a_{1} = −‖a_{1}‖$ have the same direction if $90° < θ ≤ 180°$,
 * $a$ and $b$ have opposite directions if $a_{1}$.

Vector rejection
The vector rejection of $b$ on $a_{1} = 0$ is a vector $θ = 90°$ which is either null or orthogonal to $a_{1}$. More exactly:
 * $b$ if $0° ≤ θ < 90°$ or $a_{1}$,
 * $b$ is orthogonal to $90° < θ ≤ 180°$ if $a$,

Matrix representation
The orthogonal projection can be represented by a projection matrix. To project a vector onto the unit vector $b$, it would need to be multiplied with this projection matrix: $$P_\mathbf{a} = \mathbf{a} \mathbf{a}^\textsf{T} = \begin{bmatrix} a_x \\ a_y \\ a_z \end{bmatrix} \begin{bmatrix} a_x & a_y & a_z \end{bmatrix} = \begin{bmatrix} a_x^2 & a_x a_y & a_x a_z \\ a_x a_y & a_y^2 & a_y a_z \\ a_x a_z & a_y a_z & a_z^2 \\ \end{bmatrix}$$

Uses
The vector projection is an important operation in the Gram–Schmidt orthonormalization of vector space bases. It is also used in the separating axis theorem to detect whether two convex shapes intersect.

Generalizations
Since the notions of vector length and angle between vectors can be generalized to any n-dimensional inner product space, this is also true for the notions of orthogonal projection of a vector, projection of a vector onto another, and rejection of a vector from another.

In some cases, the inner product coincides with the dot product. Whenever they don't coincide, the inner product is used instead of the dot product in the formal definitions of projection and rejection. For a three-dimensional inner product space, the notions of projection of a vector onto another and rejection of a vector from another can be generalized to the notions of projection of a vector onto a plane, and rejection of a vector from a plane. The projection of a vector on a plane is its orthogonal projection on that plane. The rejection of a vector from a plane is its orthogonal projection on a straight line which is orthogonal to that plane. Both are vectors. The first is parallel to the plane, the second is orthogonal.

For a given vector and plane, the sum of projection and rejection is equal to the original vector. Similarly, for inner product spaces with more than three dimensions, the notions of projection onto a vector and rejection from a vector can be generalized to the notions of projection onto a hyperplane, and rejection from a hyperplane. In geometric algebra, they can be further generalized to the notions of projection and rejection of a general multivector onto/from any invertible k-blade.

title: Vector projection


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Noel Coonan

Noel Coonan (born 6 January 1951) is an Irish former Fine Gael politician who served as a Teachta Dála (TD) for the Tipperary North constituency from 2007 to 2016. He was a Senator for the Cultural and Educational Panel from 2002 to 2007.

He was elected at the 2007 general election to Dáil Éireann as a Fine Gael TD for Tipperary North. He had been a member of the 22nd Seanad Éireann in 2002 as a Senator for the Cultural and Educational Panel.

A former member of North Tipperary County Council and Templemore Town Council, he was an unsuccessful candidate for Dáil Éireann in the Tipperary North constituency at the 2002 general election.

He was the Fine Gael deputy Spokesperson on Agriculture, Fisheries and Food, with special responsibility for Common Agricultural Policy reform from October 2010 to March 2011. He had been deputy Spokesperson on Communications, Energy and Natural Resources, with special responsibility for Telecommunications from 2007 to 2010. He is President of the Collins 22 Society.

He lost his seat at the 2016 general election, and was an unsuccessful candidate for election to the Seanad in April 2016.

He contested the May 2019 local elections in Tipperary, and won a seat in the Thurles-Templemore local election area. In June 2020, he was elected to the Chair of the Thurles-Templemore District Council.

title: Noel Coonan


text:
Paschal Mooney

Paschal Canice Mooney (born 14 October 1947) is an Irish Fianna Fáil politician and a former member of Seanad Éireann.

A journalist and broadcaster, he was first elected to the Seanad in 1987, on the Cultural and Educational Panel. He retained his seat at each subsequent election until losing it at the 2007 election to the 23rd Seanad. He was re-elected to Seanad Éireann on the Agricultural Panel in a Seanad by-election on 19 January 2010., re-elected in 2011, but lost his seat in the April 2016 election.

Early and personal life
Born in Dublin, he grew up in Drumshanbo, County Leitrim. His father, Joe, was a member of the Seanad (1961–1965) and Leitrim County Council (1943–1988) while his mother Eva Mooney also served as a member of Leitrim County Council (1988–1991). He is the third generation of his family to contribute to public service locally and nationally as his grandfather, Andrew Mooney, served as a member of Leitrim County Council from 1920 to 1943.

Mooney has also enjoyed a broadcasting career with RTÉ, Ireland's national broadcaster. A presenter of a variety of Irish traditional and country music and Sports programmes, he devised, scripted and presented numerous music documentaries on Irish and American country music stars. He was in the forefront of the 'Shot at Dawn' campaign led in the British House of Commons by Andrew MacKinlay MP and in the House of Lords by Alf Dubs seeking a pardon for over 300 soldiers of World War I (including 26 Irish servicemen) shot in questionable circumstances following Field courts-martial.

Mooney married Sheila Baldrey; the couple has five children.

Political career
He was first elected to the Seanad in 1987, on the Cultural and Educational Panel as a nominee of the Library Association of Ireland (LAI). He retained his seat at each subsequent election until losing it in the 2007 election. He was a member of Leitrim County Council from 1991 to 1999. He later served as a delegate to the Parliamentary Assembly of the Western European Union 1998 to 2002, and subsequently was a member of the Irish Delegation to the Parliamentary Assembly of the Council of Europe 2002–08. He was appointed a member of the British–Irish Parliamentary Assembly (BIPA) in 1997 and served until 2007. Mooney returned to the BIPA in 2011 and also sits on the North/South Parliamentary Body which meets twice yearly in Belfast and Dublin and is the representative of the Stormont Assembly and Oireachtas. In April 2008, Mooney was nominated to the position of Chairman of Fáilte Ireland North West, one of five Regional Tourism Boards in Ireland charged with promoting their regions and attracting tourists.

Mooney was selected as running mate to Seán Ó Neachtain as a Fianna Fáil candidate at the 2009 European Parliament election for the North-West constituency. Following the announcement by O'Neachtain that he was not contesting the election for health reasons, Pat "the Cope" Gallagher was nominated to contest the constituency as Mooney's Fianna Fáil running mate. Gallagher was elected as an MEP but Mooney was unsuccessful. On 19 January 2010, Mooney was elected on the first count in a Seanad by-election caused by the death of Senator Peter Callanan in October 2009. As a result, he took a seat on the Agricultural panel in the 23rd Seanad returning after an absence of two and a half years. He was re-elected at the 2011 Seanad election. He was the Fianna Fáil Seanad spokesperson on Social Protection. He was also a member of the Joint Oireachtas Committee on Agricultural and the Joint Committee on Transport, Energy and Communications.

title: Paschal Mooney


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Labhrás Ó Murchú

Labhrás Ó Murchú (born 14 August 1939) is the Director-General of Comhaltas Ceoltóirí Éireann, and a retired member of Seanad Éireann for Fianna Fáil.

Ó Murchú was born in Cashel, County Tipperary. He was a candidate in 1993 for election to the 20th Seanad by the Cultural and Educational Panel, but was unsuccessful. In 1996 the Lord Mayor of Dublin, Seán Dublin Bay Rockall Loftus, awarded him the Dublin City Lord Mayor's Award, in recognition of his many achievements in cultural and social work.

He stood again for election to Seanad Éireann in 1997, nominated by Comhaltas rather than by Fianna Fáil, and was elected to the 21st Seanad. He was re-elected in 2002 to the 22nd Seanad and in 2007 to the 23rd Seanad.

In June 2010, Ó Murchú admitted that he stayed in CCE headquarters for €50 a night bed and breakfast while attending Leinster House, but claimed a €126 overnight allowance. On 7 July 2010 he resigned the Fianna Fáil parliamentary party whip, along with John Hanafin and Jim Walsh, in protest at the Civil Partnership bill. He rejoined the Fianna Fáil parliamentary party on 23 November 2010.

He was re-elected to the 24th Seanad in 2011, despite pressure on him to resign in order to make way for newer Fianna Fáil candidates; this was a strategy devised by party leader Micheál Martin in an attempt to recover from the party's disastrous result at the 2011 general election. Ó Murchú's re-election was credited to support from Sinn Féin voters who had not contested the panel.

On 15 September 2011, at a meeting of the Fianna Fáil parliamentary party, the issue of the 2011 presidential election was raised. Unexpectedly, Ó Murchú sought to run as an independent candidate. This was widely seen as a challenge to the authority of Micheál Martin. The extended meeting broke up without agreement. The parliamentary party met again on 20 September. Ó Murchú withdrew his request for a nomination and a motion was passed that the party's Oireachtas members would not nominate or endorse any candidate.

In 2012, Ó Murchú was listed as having the worst attendance record of any Senator, having missed 19 of 61 votes. The Irish Independent newspaper later published an apology, because Ó Murchú's absence was owing to his wife's illness while on a business trip to the United States of America.

He was the Fianna Fáil Seanad spokesperson on Arts, Heritage and Gaeltacht Affairs.

title: Labhrás Ó Murchú


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Ann Ormonde

Ann Ormonde (born 20 January 1935) is an Irish former Fianna Fáil politician and was a member of Seanad Éireann from 1993 to 2011. She was elected by the Cultural and Educational Panel. She was first elected to the Seanad in 1992 and re-elected at every subsequent election until she lost her seat at the 2011 election.

Born in Kilmacthomas, County Waterford, she was educated at the Presentation Convent, Clonmel and University College Dublin. She is a former Career Guidance Counsellor.

She served as a member of South Dublin County Council for the Terenure / Rathfarnham from 1985 to 2004. She was an unsuccessful candidate for the Dáil in the Dublin South constituency at the 1987, 1989, 1992 and 1997 general elections.

title: Ann Ormonde


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Tromen

Tromen is a stratovolcano in western Argentina. It rises above the older caldera of the Volcán Negro del Tromen.

title: Tromen


text:
Talk:2005 Sunjiawan mine disaster

Untitled
I've moved this from 2005 Liaoning mine disaster to 2005 Sunjiawan mine disaster. Liaoning is a big province with 42 million people, and it is not helpful to speak of "the" mine disaster in Liaoning. -- ran (talk) 21:46, Feb 19, 2005 (UTC)

title: Talk:2005 Sunjiawan mine disaster


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Terra incognita

Terra incognita or terra ignota (Latin "unknown land"; incognita is stressed on its second syllable in Latin, but with variation in pronunciation in English) is a term used in cartography for regions that have not been mapped or documented. The expression is believed to be first seen in Ptolemy's Geography c. 150. The term was reintroduced in the 15th century from the rediscovery of Ptolemy's work during the Age of Discovery. The equivalent on French maps would be terres inconnues (plural form), and some English maps may show Parts Unknown.

Similarly, uncharted or unknown seas would be labeled mare incognitum, Latin for "unknown sea".

Details
Popular belief holds that cartographers used to label such regions with "Here be dragons". Although cartographers did claim that fantastic beasts (including large serpents) existed in remote corners of the world and depicted such as decoration on their maps, only one known surviving map, the Hunt–Lenox Globe, in the collection of the New York Public Library, actually says "Here are dragons" (using the Latin form "HIC SVNT DRACONES"). However, ancient Roman and Medieval cartographers did use the phrase HIC SVNT LEONES (Here are lions) when denoting unknown territories on maps.

Alternatively, 'terra incognita' may also refer to the hypothesized continent Terra Australis Incognita ("The unknown land of the South"), as seen in the Theatrum Orbis Terrarum map by Abraham Ortelius (1570).

During the 19th century, terra incognita disappeared from maps; both the coastlines and the inner parts of the continents became fully explored, even prior to the advent of aerial photography and satellite imagery in the 20th century. However, the bottoms of oceans remain mostly unmapped, as do many other land surfaces in the Solar System. For example, only 40% of the surface of Neptune's Moon Triton has been mapped with the remainder being terra incognita.

The phrase is now used metaphorically to describe any unexplored subject or field of research.

Etymology

 * Terra: Latin for 'earth' or 'land'. Related English words include terrestrial, territory and terrain.
 * Incognita: from Latin cognoscere 'to know, be acquainted with' (negated by the prefix 'in-'), which is related to English know and Greek γνῶσις gnosis 'knowledge'. Related English words include agnostic, cognition, gnosticism.

For more history of the terms, see Terra Australis, and also Etymology at Australia.

title: Terra incognita


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Scalar projection

In mathematics, the scalar projection of a vector $$\mathbf{a}$$ on (or onto) a vector $$\mathbf{b},$$ also known as the scalar resolute of $$\mathbf{a}$$ in the direction of $$\mathbf{b},$$ is given by:

 * $$s = \left\|\mathbf{a}\right\|\cos\theta = \mathbf{a}\cdot\mathbf{\hat b},$$

where the operator $$\cdot$$ denotes a dot product, $$\hat{\mathbf{b}}$$ is the unit vector in the direction of $$\mathbf{b},$$ $$\left\|\mathbf{a}\right\|$$ is the length of $$\mathbf{a},$$ and $$\theta$$ is the angle between $$\mathbf{a}$$ and $$\mathbf{b}$$.

The term scalar component refers sometimes to scalar projection, as, in Cartesian coordinates, the components of a vector are the scalar projections in the directions of the coordinate axes.

The scalar projection is a scalar, equal to the length of the orthogonal projection of $$\mathbf{a}$$ on $$\mathbf{b}$$, with a negative sign if the projection has an opposite direction with respect to $$\mathbf{b}$$.

Multiplying the scalar projection of $$\mathbf{a}$$ on $$\mathbf{b}$$ by $$\mathbf{\hat b}$$ converts it into the above-mentioned orthogonal projection, also called vector projection of $$\mathbf{a}$$ on $$\mathbf{b}$$.

Definition based on angle θ
If the angle $$\theta$$ between $$\mathbf{a}$$ and $$\mathbf{b}$$ is known, the scalar projection of $$\mathbf{a}$$ on $$\mathbf{b}$$ can be computed using

 * $$s = \left\|\mathbf{a}\right\| \cos \theta .$$  ($$s = \left\|\mathbf{a}_1\right\|$$ in the figure)

The formula above can be inverted to obtain the angle, θ.

Definition in terms of a and b
When $$\theta$$ is not known, the cosine of $$\theta$$ can be computed in terms of $$\mathbf{a}$$ and $$\mathbf{b},$$ by the following property of the dot product $$ \mathbf{a} \cdot \mathbf{b}$$:
 * $$ \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{a}\right\| \left\|\mathbf{b}\right\|} = \cos \theta$$

By this property, the definition of the scalar projection $$s$$ becomes:
 * $$ s = \left\|\mathbf{a}_1\right\| = \left\|\mathbf{a}\right\| \cos \theta = \left\|\mathbf{a}\right\| \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{a}\right\| \left\|\mathbf{b}\right\|} = \frac {\mathbf{a} \cdot \mathbf{b}} {\left\|\mathbf{b}\right\| }\,$$

Properties
The scalar projection has a negative sign if $$90^\circ < \theta \le 180^\circ$$. It coincides with the length of the corresponding vector projection if the angle is smaller than 90°. More exactly, if the vector projection is denoted $$\mathbf{a}_1$$ and its length $$\left\|\mathbf{a}_1\right\|$$:

 * $$s = \left\|\mathbf{a}_1\right\| $$ if $$0^\circ  \le \theta \le 90^\circ,$$
 * $$s = -\left\|\mathbf{a}_1\right\| $$ if $$90^\circ < \theta \le 180^\circ.$$

title: Scalar projection


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Viedma (volcano)

Viedma is a subglacial volcano whose existence is questionable. It is supposedly located below the ice of the Southern Patagonian Ice Field, an area disputed between Argentina and Chile. The 1988 eruption deposited ash and pumice on the ice field and produced a mudflow that reached Viedma Lake. The exact position of the edifice is unclear, both owing to the ice cover and because the candidate position, the "Viedma Nunatak", does not clearly appear to be of volcanic nature.

Geography and geomorphology
Viedma is located in the southern Patagonian Andes, southwest of Mount FitzRoy. The lake of the same name lies southwest of the volcano. The area is poorly accessible and the volcanic history poorly known.

Viedma is part of the Austral Volcanic Zone. This volcanic zone consists of six volcanoes, from north to south Lautaro, Aguilera, Viedma, Reclus, Monte Burney and Fueguino. These volcanoes form a 700 km long chain of volcanoes, the most southern of which is a volcanic complex of lava domes and lava flows on Cook Island.

Few things are known with certainty about the volcanic edifice of Viedma as it is mostly buried beneath glacial ice and the "Viedma Nunatak" was later revealed to not be a volcano. In 1956 Louis Lliboutry proposed that volcanic activity may occur in fissure vents buried beneath glaciers; between eruptions they would be concealed below the ice; Lliboutry considered dark bands on the ice to be tephra deposits, a view supported by a 1958-1959 expedition that found pumice on the Viedma Glacier. Other reports of volcanic phenomena in the region exist, and the existence of a large caldera beneath the Southern Patagonian Ice Field has been suggested as an explanation for volcanism there.

Viedma Nunatak
The Viedma Nunatak is commonly interpreted to be the site of the volcano, after observations made in 1944-1945 and 1950 by survey flights including controversial sightings of fumaroles which also led to the nunatak becoming known as the "Volcan Viedma"; but the lack of clear evidence and the difficulty of field sampling has rendered its identification with the Viedma vent contentious.

The nunatak is about 1500 m high above sea level. Most of the mountain is buried beneath the Viedma Glacier of the Southern Patagonian Ice Field and only parts of it crop out. The outcropping nunatak is elongated in north–south direction. A number of structures interpreted as craters and concave depressions are found especially on the southern part of the volcano, some of which are lined up in north–south direction. The northern sector of the volcano was apparently more heavily affected by glacial erosion; conversely, several craters in the southern sector appear to be young. The nunatak shows clear evidence of glacial action, including glacial striations and coverage by glacial drifts; the Viedma glacier may once have crossed the nunatak in its central part. Rock samples taken from the nunatak are Jurassic metamorphic rocks, including gneiss and schists, and no evidence of magmatic rocks was found in a 1958-1959 expedition.

Different observations have yielded different sizes and numbers of supposed craters; González-Ferrán et al. 1995 reported several craters and calderas with sizes ranging 1.5 - 4 km, while Kobayashi et al. 2010 observed fewer craters and none of them larger than 1.5 km. These craters were later interpreted as being actually glacial cirques containing tarn lakes.

Geology
Off the southernmost west coast of South America, the Antarctic Plate subducts beneath the South American Plate at a rate of 3 cm/year. This subduction process is responsible for volcanism in the Austral Volcanic Zone. The Austral Volcanic Zone is one of four volcanic zones in the Andes, the other three are the Northern Volcanic Zone, the Central Volcanic Zone and the Southern Volcanic Zone, all of which are separated from the Austral Volcanic Zone and each other by gaps where no volcanic activity occurs. Unlike the Austral Volcanic Zone, volcanism in these other zones is controlled by the subduction of the Nazca Plate beneath the South American Plate.

The Austral Volcanic Zone was identified as such in 1976, but some volcanoes were identified and localized later. Owing to their similar composition the three northerly volcanoes Lautaro, Viedma and Aguilera are grouped as the "northern Austral Volcanic Zone". Volcanism in the Austral Volcanic Zone is not well known before the Holocene; it is likely that a lull of volcanism occurred before the Pliocene while the Chile Triple Junction was being subducted in the region. Magmas from the Austral Volcanic Zone are adakitic owing to the melting of the subducting slab and the interaction of these melts with the crust and mantle.

The basement consists of metamorphic rocks of Paleozoic age. Outcrops of the basement are found around the volcano and could even occur on the edifice that crops out from the glaciers. The regional basement is formed by these Paleozoic and younger metamorphic and sedimentary rocks as well.

Composition
Viedma like other volcanoes of the Austral Volcanic Zone has erupted andesite and dacite. Phenocrysts include amphibole, biotite, hypersthene and plagioclase; orthoclase, plagioclase and pyroxene also occur as xenoliths. The rocks form a calcalkaline suite, but there is also an adakitic signature. The xenoliths may reflect a crustal contamination of the magma erupted at Viedma.

Eruption history
Tephra attributed to Viedma has been found in the Laguna Potrok Aike, including three tephra layers 26,991 - 29,416, 40,656 - 48,219 and 41,555 - 57,669 years before present which may originate either on Viedma or on Lautaro.

Viedma has erupted during the Holocene; a tephra found in Lago Cardiel and dated 3,345 - 3,010 years before present may have originated at Viedma, although Aguilera and Lautaro are also candidate source volcanoes. Due to the absence of traces of volcanism at Viedma Nunatak the Global Volcanism Program removed its entry for Viedma in 2019.

Historical
Many observations referring to volcanic activity on the Southern Patagonian Ice Field exist, including reports of ashfalls, layers of tephra on glaciers and columns of smoke rising from the ice.

A subglacial eruption occurred in 1988, depositing ash and pumice on the Viedma Glacier. These materials later gave rise to a lahar. The eruption had melted part of the ice and formed a network of valleys; it was assumed that it had taken place at some point between September and November of that year.

Hazards
There are no major population centres close to any volcano in the Austral Volcanic Zone, and the volcanoes are largely unmonitored. Among the know eruptions are large Holocene explosive eruptions, while historical eruptions took place in 1908 at Reclus and 1910 at Monte Burney. Future eruptions of volcanoes in the Austral Volcanic Zone may lead to ash fall at large distances from the volcano, including interruptions in air traffic and direct ash damage. Viedma is considered to be Argentina's 10th most dangerous volcano.

title: Viedma (volcano)


text:
User:Hayabusa future

Name: WiIIiam Arya

Location: Medan, Indonesia & Melbourne, Australia

I do mostly interwikis to Indonesian Wikipedia.

Quick links

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Pic of the day...
id:Pengguna:Hayabusa future ms:Pengguna:Hayabusa future

title: User:Hayabusa future