Yep, since only metamorphic rocks have metamorphosed, there is only a grade of metamorphism for metamorphic rocks. However, metamorphic rocks do have parent rocks (e.g. slate's parent rock is shale, a sedimentary rock) which I guess you could think of as a 0th grade metamorphism; a rock that, once metamorphosed into another rock, is metamorphic.Is grade of metamorphism only for metamorphic rocks? Because I cant find anything for igneous or sedimentary.
Bowen's Reaction Series is for igneous rocks- it's basically the order in which different minerals crystalise as magma rises. As the magma rises, it cools from very high temperatures; minerals with higher melting points will crystalise first and those with lower melting points crystalise last. Here's a typical chart:Also, what is Bowen's Reaction Series, and is it different for every rock?
Not entirely sure, but if I remember correctly, chalcedony is defined as quartz without a visible crystal structure, so maybe because agate & onyx have no visible crystal structure, while other quartzes do?So let me get this straight, Agate/Onyx are varieties of Chalcedony, which is a variety of quartz. In addition, this means the varieties of Agate/Onyx (Ex. Banded Agate) are theoretically varieties of chalcedony. Why are Agate/Onyx varieties of chalcedony and not all the other quartzs as well? All the quartzes share chemical formula, crystal system, hardness, etc so why is Agate/Onyx specifically a variety of chalcedony only?
Have you tried using Audubon, Smithsonian, field guides, etc? I used a couple of detailed geology books from my local library to study. If you still can't find them listed as separate rocks, I think it should still be fine. Aren't the two rocks very similar anyway, besides the inclusions of the different minerals?I can't find info on garnet schist and mica schist as separate rocks; everywhere I look has them as one rock, but the list has them as two separate ones. Does anyone have a website or resource I could use? (:
How does gneiss form? In order to answer that you need to figure out how metamorphic rocks in general form, and the specific case for gneiss. Do that for several rocks and you'll start to see some patterns. Good luck!I'm new here so sorry if I'm posting in the wrong place D: But I was wondering, in the rules, it says one of the topics under "rocks" is the "rock cycle." So, for example, if I'm studying the metamorphic rock Gneiss, what would be the "rock cycle" for that particular rock? Thanks in advance!
"Don't expect either; be prepared for both."Now for my question: I'll be at an invitational in a few days held at a high school, should I expect to see real specimens or pictures?
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