Questions tagged [petrology]
Petrology is the study of rocks and the processes that lead to their formation and alteration.
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Can serpentinite come from basalt?
During ultramafic alteration can serpentinite form?
Can basalt be the parent rock of serpentinite?
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Estimation of rare earth elements in the SUAC complex
I am currently competing in a case study competition a part of which has asked us to estimate the amount of Nd, Pr, and Dy in the SUAC complex (Sung Valley Ultramafic-Alkaline-Carbonatite) in electric ...
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Why was quartz not a major product of the Lunar Magma Ocean?
Fractional crystallisation generally makes magma more silicic. Why was a substantial quartz layer not a product of the stratification of the Lunar mantle?
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Why are grain coatings an important mechanism for preserving porosity during burial in sandstone but not in carbonate?
I am writing a paper on the role of petroleum emplacement and grain coatings in preserving porosity during burial. I can find many sources discussing grain coatings stopping cementation in sandstone, ...
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On QAPF (Steckeisen) diagrams, should Albite be considered on the Alkali feldspar or Plagioclase side? Or in-between?
QAPF diagrams are double ternary diagrams used for magmatic rock classification based on mineralogy.
Quartz and Feldspathoids are opposed on the pointy ends of the diamond, with Alkali feldspar and ...
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How is felsic magma produced at island arcs?
I previously believed that continental crust owes its lower density to the partial melting of oceanic crust; the mantle would partially melt at mid-ocean ridges to produce basaltic crust, and when ...
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What is the sedimentary form of gabbro/diabase? What would it look like?
Gabbro is an intrusive, mafic, and igneous rock. How would it turn into sedimentary rock?
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What is the electrical conductivity of a liquid Komatiite?
I am searching for previous work that has determined the electrical conductivity range for komatiites at the surface. Does anyone have some values or references?
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Are we observing sedimentary rock formation today?
For instance, are we able to see the microscopic accumulation of shale or limestone?
Can anyone reference me to sandstone formation observation, that would have to occur more rapidly. I’ve heard it ...
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How did this stone become encased within different rock?
My father, in his younger years, was a stone mason in Cincinnati Ohio. A couple of decades ago he was building a wall of some kind. He would fetch rock from a creek bed, haul it to the construction ...
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Are these igneous Liesegang rings on a popular Oahu, Hawaii hike?
I hiked the Lanikai Pillbox trail (Oahu, HI). I noticed eroded concentric rings in the igneous rock with a hard center. I'm unable to find the geologic cause of these rings. Are they Liesegang rings? ...
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regarding four-way closure in structural geology
I am a little bit confused on the two concepts in structural geology, i.e., what is the relationship of anticline and four-way closure. My understanding is that anticline belongs to four-way closure. ...
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Can we separate a sandy, clayey & salt layer on basis of their rheological properties?
Since, given enough compaction, salt is able to behave like a fluid & buoyant too if it's overlain by a higher density rock (it could be fine grained clay or a sandy sequence). But in another case,...
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What is the difference between mobile & molten rock?
In the book Fundamentals of Geomorphology (Routledge Fundamentals of Physical Geography) by Richard John Huggett there is a sentence " Intruded rocks, which must be mobile but not necessarily molten,...
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When sediments are deposited, do they sink into the earth?
I was listening to a geology podcast describing how sedimentary rock forms and later turns into metamorphic rock. As a river lays down sediment, the lower layers can eventually be several kilometers ...
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