How can you tell the difference between a meteor and volcanic rock? What would you look for?

Answer 1

As meteoroids are heated during passage through the atmosphere, their surfaces melt and experience ablation. They can be sculpted into various shapes during this process, sometimes resulting in deep "thumb-print" like indentations on their surfaces called regmaglypts. If the meteoroid maintains a fixed orientation for some time, without tumbling, it may develop a conical "nose cone" or "heat shield" shape. As it decelerates, eventually the molten surface layer solidifies into a thin fusion crust, which on most meteorites is black (on some achondrites, the fusion crust may be very light colored). On stony meteorites, the heat-affected zone is at most a few mm deep; in iron meteorites, which are more thermally conductive, the structure of the metal may be affected by heat up to 1 cm below the surface. Meteorites are sometimes reported to be warm to the touch when they land, but they are never hot. Reports, however, vary greatly, with some meteorites being reported as "burning hot to the touch" upon landing, and others forming a frost upon their surface.

About 86% of the meteorites that fall on Earth are chondrites, which are named for the small, round particles they contain. These particles, or chondrules, are composed mostly of silicate minerals that appear to have been melted while they were free-floating objects in space. Chondrites also contain small amounts of organic matter, including amino acids, and presolar grains. Chondrites are typically about 4.55 billion years old and are thought to represent material from the asteroid belt that never formed into large bodies. Like comets, chondritic asteroids are some of the oldest and most primitive materials in the solar system. Chondrites are often considered to be "the building blocks of the planets."

.About 8% of the meteorites that fall on Earth are achondrites, some of which appear to be similar to terrestrial mafic igneous rocks

About 5% of meteorites that fall are iron meteorites with intergrowths of iron-nickel alloys, such as kamacite and taenite. Most iron meteorites are thought to come from the core of a number of asteroids that were once molten

Stony-iron meteorites constitute the remaining 1%. They are a mixture of iron-nickel metal and silicate minerals.

Volcanic rock is an igneous rock of volcanic origin.

Volcanic rocks are usually fine-grained or aphanitic to glassy in texture. They often contain clasts of other rocks and phenocrysts. Phenocrysts are crystals that are larger than the matrix and are identifiable with the unaided eye. They were created during fractional crystallization of magma before extrusion. Rhomb porphyry is an example with large rhomb shaped phenocrysts embedded in a very fine grained matrix.

Volcanic rocks often have a vesicular texture, which is the result voids left by volatiles escaping from the molten lava. Pumice is a rock, which is an example of explosive volcanic eruption. It is so vesicular that it floats in water.

Pyroclastic rocks are the product of explosive volcanism. They are usually felsic (high in silica). Examples of pyroclastic rocks are tuff and ignimbrite.

Answer 2

First, if you found a rock that fell from the sky it would be a meteorite, not a meteor (a meteor is the streak you see). The way scientists tell if a rock is a meteorite is by slicing a piece off and looking for what they call weidmanstatten figures (the spelling is close, but may not be correct). These outline the peculiar crystalline structures within the meteorite. Now, unless you live where the glaciers were, a very unusual appearing rock is quite possibly a meteor (the glaciers brought with them many types of unusal stones, which glacial geologists call 'glacial erratics'). For example, if you live in Kansas and find a rock composed of iron, you can start suspecting that it is a meteorite. You would not expect such a rock in that area.

Answer 3

A pluton was molten rock that just never made it to the surface before it cooled and solidified. If you look at plutonic rock and volcanic rock in the same area, the composition will be similar. The big difference you see will be the size of the crystals of the individual minerals in the rock. When crystals form over long periods of time, similar ions and compounds orient themselves with pre-existing crystals, and add to the size of the crystal. When they form quickly, like when lava solidifies at the surface, the crystals are much smaller, and are often microscopic. There are also amorphous rocks with no crystal structure (volcanic glass). See the link for pictures. Plutonic rocks are 'intrusive' rocks, volcanic rocks are 'extrusive.'

Answer 4

Metal meteorites are typically heavy, have a fusion crust, thumb prints, are attracted to a magnet, and contain nickle. In all reality though, it can be difficult to distinguish meteorites from terrestrial rocks, however.

Here's a good meteorite identification website which focuses mainly on meteorwrongs but some proved to be actual meteorites that even the experts mis-identified.

http://epsc.wustl.edu/admin/resources/meteorites/meteorwrongs/meteorwrongs.htm

Answer 5

If a volcano isn't near by you can rule that out.

Answer 6

Wow! Thanks! exactly what I was looking for. I looked for the answers on other websites but I couldn't find them.