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Dr. Gregory W. ClarkSpring 2019

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SC

209• Igneous Rocks

• Lab activity

Base Groups

BGDG: If you could be an animal for a day, what animal would it be and why?

BG Procedure: BGWS (& any HW questions)

BG processing

Questions?

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Igne

ous

Cla

ssifi

catio

n

Variables in Magma Formation Heat Most important

Geothermal Gradient

PressureVariation in P with depth

Increase in MP with depth

VolatilesWater & gasses (CO2, SO2)

Decrease in MP

Geothermal Gradient

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Lots O’ Rocks From One Source?

Crystal settlingMagmatic differentiation

Assimilation “Country rock” incorporated

Magma mixing Different magma bodies converge

Partial Melting – relate to Bowen Reaction series

Lots O’ Rocks From One Magma?

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Lots O’ Rocks From One Source?

Crystal settlingMagmatic differentiation

Assimilation “Country rock” incorporated

Magma mixing Different magma bodies converge

Lots O’ Rocks From One Magma? Crystal settlingMagmatic differentiation

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Partial cooling – relate to Bowen Reaction series:high melting point/freezing point rocks crystallize first

Lots O’ Rocks From One Magma?

Lots O’ Rocks From One Magma?

AssimilationExisting “country rock”

dislodged and incorporated into melt as magma rises through brittle lithosphere

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Lots O’ Rocks From One Magma?Magma mixing Different magma bodies converge

Lots O’ Rocks From One Source?A related phenomenon:Partial melting

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Have a g

reat day!