Stony-iron Meteorites: An Introduction

Ғылым және технология

UCLA Meteorite Gallery Lecture Series - December 2021
Title: Stony-iron Meteorites: An Introduction
Lecturer: Dr. Alan Rubin; UCLA
There are two main kinds of stony-irons: pallasites and mesosiderites. Pallasites consist of roughly half metallic Fe-Ni and half magnesian olivine; these rocks were derived from the core-mantle boundaries of differentiated asteroids. Most pallasites belong to the main group (PMG) and are related to HED samples and IIIAB iron meteorites. Five pallasites belong to the Eagle Station (PES) group; these rocks are from differentiated carbonaceous-chondrite-like
asteroids. Their olivine grains are more ferroan than those of PMG (Fa20 vs. Fa12). There are also a few pyroxene pallasites that contain more pyroxene than PMG or PES and have distinct O-isotopic compositions.
Mesosiderites contain approximately half silicate and half metallic Fe-Ni, but the silicate in these rocks is mainly basaltic with relatively little olivine. Mesosiderites are impact breccias, probably formed by the collision of a largely molten metallic core with the basaltic crust of another differentiated asteroid. This occurred early in Solar-System history.
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Пікірлер: 34

  • @freshimpactco.8698
    @freshimpactco.86982 жыл бұрын

    A fantastic presentation

  • @eeeeeeeerror
    @eeeeeeeerror2 жыл бұрын

    Thank you for this great content!

  • @freshimpactco.8698
    @freshimpactco.86982 жыл бұрын

    Incredibly rich and informative video absolutely loved every minute of it. 👍🏻✅

  • @Infinit.Starlights
    @Infinit.Starlights11 ай бұрын

    Very helpful and educational great efforts my brother✨

  • @lyda9335
    @lyda9335 Жыл бұрын

    I like this video 😍 Thanks you 💕 Great 👍 meteorite

  • @normainiguez8535
    @normainiguez85352 жыл бұрын

    Asombroso 🤩

  • @MatthewLong8
    @MatthewLong82 жыл бұрын

    Great video. seems to be pretty comprehensive of the given topic. I especially appreciate the inclusion of open mysteries like the missing olivine from mesosiderites and I agree that the metallic impactor hypothesis seems plausible but I wonder what the cooling rate would be of a naked core. those bodies would have to be in fairly close proximity. One thing I would like to know more about is variation of impact energies and the effects in relation to melting and mixing therein.

  • @anniesoucek8216
    @anniesoucek8216 Жыл бұрын

    Why was the New England Meteorite Lab result for my rocks was not a meteorite when it contents white metal grains and colored metal grains. It contents a lot of metals and ruby gemstones. Of course I sent them 2 tiny rocks without grains in it because it is in their instructions to send a sample as little as a marble. I've watched a lot of earth rocks videos, but I don't see a rock like mine. In fact some of the white metal grains have widmanstatten pattern.

  • @user-dp2dg3lj3d
    @user-dp2dg3lj3d6 ай бұрын

  • @nixonsmateruby1
    @nixonsmateruby1 Жыл бұрын

    If a pallasite is metal with crystal, what would a Meteorite be called if it had stone swapped for the metal, so still had big olivine crystals but in a stone matrix, or has one not been found?

  • @ronaldbascus801
    @ronaldbascus8012 жыл бұрын

    Interesting talk I love it I have a small iron meteorite with a piece of iron fused to it in that piece there is what looks like roots with soil or something like fabric nothing I have ever seen in a meteorite they are visible with the naked eye you can hold them with your fingers I think this could be the most important find ever tell me what you think

  • @ghostmanscores1666
    @ghostmanscores1666 Жыл бұрын

    I watched it twice in a row.

  • @ghostmanscores1666

    @ghostmanscores1666

    Жыл бұрын

    edit: three times

  • @raul568
    @raul5682 жыл бұрын

    Alan, I'm selling a METEORITE..

  • @c..s.gamestone571

    @c..s.gamestone571

    2 жыл бұрын

    You are from

  • @martinocole3211
    @martinocole32112 жыл бұрын

    A fantastic talk, but a couple questions . . . 1) Are there any meteorites that contain bits of iron with a composition suggesting they were sourced from a collision involving an earlier differentiated asteroid while it was still molten, or otherwise? 2) Is there evidence for ductility contrast or metallic ductile deformation around silicate minerals resulting from the collisions that broke or tore apart differentiated asteroids to form iron and stony iron meteoroids? Or is the metallic component brittle under those conditions? Thank you

  • @uclameteoritecollectiongal5081

    @uclameteoritecollectiongal5081

    2 жыл бұрын

    Hi @Martino Cole, we will get back to you with the answers to this question. Thank you!

  • @uclameteoritecollectiongal5081

    @uclameteoritecollectiongal5081

    2 жыл бұрын

    1. The metal in mesosiderites appears to have been molten when it was introduced into the silicate crust of the target parent asteroid. We know this because the metal nodules have a bulk IIIAB composition, but there is little compositional variation among nodules. 2. Metal-sulfide is the lowest melting phase in chondrites, so generally, collisions will cause local concentrations of metal and sulfide to melt and flow, forming veins.

  • @mikeward7290
    @mikeward72902 жыл бұрын

    I know a gal that has two iron meteorites that she might consider selling. Who buys them and how much are they worth?

  • @meteoriterecoveryoperation8674
    @meteoriterecoveryoperation86742 жыл бұрын

    Vaca Muerta is a very large Meteorite. Does every piece that's found represent an A1? I assume the answer is yes. I'm having trouble with the reasoning there are so many subtypes of the same type of Meteorite when only 2 asteroids collided. All I can think of is that the surface that collided face to face would of had more recrystallation and areas of the asteroid farther away from the impact surface had less. For instance the area of the asteroid that broke up closest to the surface that impacted would be the rarest type because less volume of the asteroids took the most of the brunt from impact where as the back end of the asteroid had maintained angular clasts and metal that is more disperse because it was the part farthest from the surface that impacted . And Inbetween was moderately recrystallized. As the asteroids broke up in many pieces would this explain why there are multiple subtypes?

  • @uclameteoritecollectiongal5081

    @uclameteoritecollectiongal5081

    Жыл бұрын

    The most commonly discussed model for mesosiderite formation is that the metal and an overlying thin silicate-mantle veneer of a projectile collides with the basaltic surface of a larger target asteroid at low relative velocity. Type-1 mesosiderites formed after this impact, Vaca Muerta among them. It was during subsequent smaller-scale impacts that the mesosiderites were metamorphosed and recrystallized. Although it is possible that parts of Vaca Muerta vary in metamorphic grade and in the proportions of orthopyroxene and tridymite, the bulk of the mesosiderite is A1. We cannot extrapolate further about an individual mesosiderite containing different portions of the projectile.

  • @christopherfritz.bigsaving
    @christopherfritz.bigsaving Жыл бұрын

    I think it looks like this

  • @christopherfritz.bigsaving
    @christopherfritz.bigsaving Жыл бұрын

    I believe I have the cores to prove this theory

  • @fatmirscollectables9240
    @fatmirscollectables9240 Жыл бұрын

    Kam ca gure keni mundesi te me tregoni ju lutem se me duken si meteorite .

  • @demiradam1627
    @demiradam16272 жыл бұрын

    Hi master

  • @janinemenezes_
    @janinemenezes_2 жыл бұрын

    Achei um meteorito muito lindo e quero vender

  • @muhammadfurkan215
    @muhammadfurkan215 Жыл бұрын

    I think, i have pallasite.

  • @janinemenezes_
    @janinemenezes_2 жыл бұрын

    Sou do Brasil

  • @muhammadfurkan215
    @muhammadfurkan2155 ай бұрын

    🤔

  • @mango561
    @mango5612 жыл бұрын

    The core of any celestial body is extremely rich in platinum group metals and gold. Enough with the ppm theory. Iron and nickel aren't heavy enough to concentrate in the center. Palladium is one of the main metals in the core.

  • @VeluKumar-rf3pe
    @VeluKumar-rf3pe Жыл бұрын

    I have more meteorite +100kg

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