Petrology
This presentation is the property of its rightful owner.
Sponsored Links
1 / 22

Petrology PowerPoint PPT Presentation


  • 107 Views
  • Uploaded on
  • Presentation posted in: General

Petrology. The study of the properties of rocks and the processes behind their formation Recognition and description of rocks Interpretation of their origin and history. Instructor. Michael F. Sheridan email: [email protected] Homepage: http://www.eng.buffalo.edu/~mfs

Download Presentation

Petrology

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.


- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -

Presentation Transcript


Petrology

Petrology

  • The study of the properties of rocks and the processes behind their formation

  • Recognition and description of rocks

  • Interpretation of their origin and history


Instructor

Instructor

  • Michael F. Sheridan

  • email:

    • [email protected]

  • Homepage:

    • http://www.eng.buffalo.edu/~mfs

  • Office hours:

    • We & Th 1:00-2:00 PM


Fundamentals

Fundamentals

  • Classification

  • Changing States (Equilibrium)

  • Plate Tectonics & Petrology

  • Thermodynamics

  • Kinetics


Magmatic rock bodies

Magmatic Rock Bodies

  • Study of rocks in hand sample

  • Descriptive Petrochemistry

  • Origin and evolution of magmas

  • Interpretative Petrochemistry


Study of rocks in hand sample

Study of rocks in hand sample

  • Fabric

  • Rock forming minerals

  • Classification


Fabric

Fabric

  • Phaneritic

  • Aphanitic

  • Glassy

  • Clastic


Sequence of mineral formation

Sequence of mineral formation

  • Degree of perfection of form

  • Inclusion within other minerals

  • Chemical zonation

  • Signs of deformation

  • Secondary growth

  • Alteration to secondary minerals


Rock forming minerals

Rock forming minerals

  • Feldspars

  • Quartz

  • Pyroxenes

  • Olivines

  • Amphiboles

  • Micas

  • Feldspathoids


Classification

Classification

  • Leucocratic

  • Felsic

  • Silicic

  • Mafic

  • Ultramafic


Rock suites

Rock Suites

  • Mafic and ultramafic

  • Calc-alkaline

  • Highly alkaline


Descriptive petrochemistry

Descriptive Petrochemistry

  • Chemical analyses

    • Major elements

    • Trace elements

  • Relation of chemistry to mineralogy


Chemical classification

Chemical classification

  • Silica concentration

    • Acid >66%

    • Intermediate 52-66%

    • Basic 45-52%

    • Ultrabasic <45%


Silica saturation

Silica saturation

  • Oversaturated

    • compatible with quartz

  • Saturated

    • Neither undersaturated minerals nor quartz

  • Undersaturated

    • undersaturated minerals


Alkali aluminum saturation

Alkali/Aluminum saturation

  • Relative to feldspar composition

    • NaAlSi3O8

  • Peralkaline

  • Peraluminous

  • Calc-alkaline


Cipw norm

CIPW norm

  • Definition

  • How calculated

  • Use in classification


Chemistry of rocks

Chemistry of rocks

  • Major elements

  • Trace elements

  • CIPW norm


From mineral composition to rock composition

From Mineral Composition to Rock Composition

  • Determine the minerals present

  • estimate their abundance

  • Calculate the rock composition using proper weightings


Interpretative petrochemistry

Interpretative Petrochemistry

  • Models of crystallization

  • Concepts of magma movement

  • Secondary alteration


Ultramafic rock bodies

Ultramafic rock bodies

  • Petrography of gabbroic and ultramafic rocks

  • Nature of Plutons

  • Oceanic subalkaline basaltic to ultramafic associations

  • Ophiolites


Petrography of gabbroic and ultramafic rocks

Petrography of gabbroic and ultramafic rocks

  • General

    • phaneritic grain size

    • may be nearly monomineralic

      • Pyroxene

      • Olivine

      • Plagioclase

  • Fabric

    • Slow sequential growth

    • Hypidiomorphic granular


Petrography of gabbroic and ultramafic rocks1

Petrography of gabbroic and ultramafic rocks

  • Classification

  • Alteration

    • deuteric and hydrothermal alteration

    • Serpentine

    • Secondary iron oxide

    • brucite & talc


Nature of gabbroic plutons

Nature of Gabbroic Plutons

  • Dikes, sills, and plugs

  • Layered intrusions

  • Slow shallow cooling of basaltic magma


  • Login