Rock cycle

The rock cycle is a general model that describes how various geological processes create, modify, and influence rocks (Figure 1). This model suggests that the origin of all rocks can be ultimately traced back to the solidification of molten magma. Magma consists of a partially melted mixture of elements and compounds commonly found in rocks. Magma exists just beneath the solid crust of the Earth in an interior zone known as the mantle.

Igneous rocks form from the cooling and crystallization of magma as it migrates closer to the Earth's surface. If the crystallization process occurs at the Earth's surface, the rocks created are called extrusive igneous rocks. Intrusive igneous rocks are rocks that form within the Earth's solid lithosphere. Intrusive igneous rocks can be brought to the surface of the Earth by denudation and by a variety of tectonic processes.

All rock types can be physically and chemically decomposed by a variety of surface processes collectively known as weathering. The debris that is created by weathering is often transported through the landscape by erosional processes via streams, glaciers, wind, and gravity. When this debris is deposited as a permanent sediment, the processes of burial, compression, and chemical alteration can modify these materials over long periods of time to produce sedimentary rocks.

A number of geologic processes, like tectonic folding and faulting in the Earth's crust, can exert heat and pressure on both igneous and sedimentary rocks causing them to be altered physically or chemically. Rocks modified in this way are termed metamorphic rocks.

All of the rock types described above can be returned to the Earth's interior by tectonic forces at areas known as subduction zones. Once in the Earth's interior, extreme pressures and temperatures melt the rock back into magma to begin the rock cycle again.

Rock cycle is important for recording the earth's history in the universe and expressing the earth's dynamic.

Further Reading

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See original: Featured Articles - Encyclopedia of Earth Rock cycle

NftFC #1: Assembling West Gondwana in the Neoproterozoic: Clues from the São Francisco craton region, Brazil

This paper summarizes the assembly of the various mesoproterozoic blocks into West Gondwanaland. In this model, The SaoFrancisco/Congo craton first collides with the Rio de la Plata craton around 730 MA. This combined Sf-C-RdlP craton then collides with the Amazonia/ W. Africa craton at around 630 MA, sandwiching and deforming the Borborema terrane, and causing internal deformation in the...

1. Fernando F. Alkmim, 2. Stephen Marshak, & 3. Marco A. Fonseca. (2001) Assembling West Gondwana in the Neoproterozoic: Clues from the São Francisco craton region, Brazil. Geology, 29(4), 319-322. info:/


See original: Research Blogging - All Topics - English NftFC #1: Assembling West Gondwana in the Neoproterozoic: Clues from the São Francisco craton region, Brazil

Oxytocin: Starting with the basics [Neurotopia]

So sometimes, Sci gets questions, and sometimes those questions...are close enough to requests. And so, today Sci will begin what is probably going to be an extensive basic series on oxytocin. We ALL love oxytocin, right? Right! And we all missed Sci's big honkin' basic science posts right? Of course right!

So the question basically came down to this: What are the effects of oxytocin in female vs males, in particular the effects on sexual and bonding behavior, and how does this influence the autonomy of people (eg, are we really the tools of our hormones). The short answer: yes and no. The long answer: is very long. So today Sci is going to begin with a background post on oxytocin, what it is, where it acts, and some basic functions. The next post will be on effects of ocytocin in females specifically, and then a post on ocytocin in males specifically. And then, the synthesis. And interspersed in there, a few Friday Weird Sciences. I mean, oxytocin makes for some GREAT weird science. :) Keep in mind, though, that although Sci has done a boatload of research getting ready to blog this topic, she by no means going to hit ALL of EVERYTHING. She might have to blog some specific papers in the future, and she definitely welcomes anyone willing to chime in the comments with more info!

So here we go.

Oxytocin

oxytocin.jpg
(Complicated molecule, complicated actions)

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See original: ScienceBlogs Select Oxytocin: Starting with the basics [Neurotopia]

@Palsule ..and what an irony that I am always on the free-will side though my views on success may overtly seem deterministic.

sandygautam: @Palsule ..and what an irony that I am always on the free-will side though my views on success may overtly seem deterministic.

See original: Twitter @Palsule ..and what an irony that I am always on the free-will side though my views on success may overtly seem deterministic.

@Palsule I've had debates on free-will on twitter earlier also. its fun:-) .really forces u to delineate u'r position precisely

sandygautam: @Palsule I've had debates on free-will on twitter earlier also. its fun:-) .really forces u to delineate u'r position precisely

See original: Twitter @Palsule I've had debates on free-will on twitter earlier also. its fun:-) .really forces u to delineate u'r position precisely

@bindureddy Agreed that itss hard to accurately and unbiaiedly quantize efforts, but the sole focus on success as a yardstick is not healthy

sandygautam: @bindureddy Agreed that itss hard to accurately and unbiaiedly quantize efforts, but the sole focus on success as a yardstick is not healthy

See original: Twitter @bindureddy Agreed that itss hard to accurately and unbiaiedly quantize efforts, but the sole focus on success as a yardstick is not healthy

@ngkabra u cant practise being born in the right era at the right place..as galdwell argues in Outliers.u can use ur luck but not create it

sandygautam: @ngkabra u cant practise being born in the right era at the right place..as galdwell argues in Outliers.u can use ur luck but not create it

See original: Twitter @ngkabra u cant practise being born in the right era at the right place..as galdwell argues in Outliers.u can use ur luck but not create it