petrologi2 SKS teori

1 SKS praktikum

by:

hill. gendoet hartono

Semester 2, 2017-2018

[TGS7208]

Siklus Batuan, Kontrak Kuliah, Kelulusan, & Praktikum Magma, Diferensiasi, Viskositas, Gas dan Komposisi Batuan Beku, Intrusi Dalam & Karakteristiknya Batuan Gunung Api, Intrusi Dangkal & Karakteristiknya Batuan Gunung Api, Lelehan, Letusan & Karakternya Klasifikasi Batuan Beku & Gunung Api Batuan Alterasi

Batuan Sedimen, Jenis & Proses Pembentukan Batuan Sedimen Silisiklastika Batuan Sedimen Karbonat Klasifikasi Batuan Sedimen Batuan Metamorf, Jenis & Proses Pembentukan Batuan Metamorf Derajat Rendah, Menengah & Tinggi Klasifikasi Batuan Metamorf

Minerals to Rocks: Major Rock Groups

Classification – how to separate different object into

groups

Types of Igneous Rock

Igneous textures

Texture is used to describe the overall appearance of a rock based on the size, shape, and arrangement of interlocking

minerals

Igneous textures Factors affecting crystal size

Rate of cooling

Fast rate forms many small crystals

Very fast rate forms glass

Slow rate promotes the growth of fewer but larger crystals

Amount of silica (SiO2) present

Amount of dissolved gases

Fine-grained Coarse-grained

Large crystals in matrix Glassy

fast cooling

magma/ lava

forms at or

near surface

sometimes

holes present

can’t see

individual

crystals

forms far below

surface

slow cooling

intergrown

crystals

magma cooled

slowly for a while

then erupted

minerals

crystallize at

different

temperatures

and or rates

very rapid cooling

ions unable to

unite in orderly

crystalline structure

Min

era

log

y of

com

mon

ig

neo

us

rock

s

Cla

ssif

ica

tion

of

ign

eou

s ro

cks

Langkah penting

Ukuran Butir DeskripsiUkuran butir

Dimana batuan terbentuk ? Di permukaan bumi: EktrusiDi dalam bumi: Intrusi

Bubbles? Ya= Vesikuler

Bubbles? Bukan=bukan vesikuler

Color Very LightLightNotVery Light Not Very DarkDarkVery DarkNeither Light nor Dark

Ligh

tes

t

Da

rke

st

Density Very Light Light Dense Very DenseMedium Density

Finding The MineralsIdentify the rock Unless you have other information,

work in the middle of the rock’s box.

This is the amount of Potassium Feldspar in the rock.

This is the amount of Quartz in the rock.

Ini sejumlah Plagioklas Feldspar di dalam batuan.

Gunakan kertas milimeter blok untuk mengukur persentasenya.

Potassium Feldspar 25%

Quartz 40%

Latihan Name a light-colored, fine-grainedrock with no bubbles.

Rhyolite

Name a coarse-grained, dense rock.

Gabbro

A classification of the phaneritic igneous rocks. a.

Phaneritic rocks with more than 10% (quartz + feldspar +

feldspathoids). After IUGS. From your text: An

Introduction to Igneous and Metamorphic Petrology, John

Winter, Prentice Hall.

The rock must contain a total ofat least 10% of the minerals below.Renormalize to 100%

Quartz-richGranitoid

9090

6060

2020Alkali Fs.Quartz Syenite

QuartzSyenite

QuartzMonzonite

Quartz

Monzodiorite

Syenite Monzonite Monzodiorite

(Foid)-bearingSyenite

510

35 65

(Foid)-bearingMonzonite

(Foid)-bearingMonzodiorite

90

Alkali Fs.Syenite

(Foid)-bearingAlkali Fs. Syenite

10

(Foid)Monzosyenite

(Foid)Monzodiorite

Qtz. Diorite/Qtz. Gabbro

5

10

Diorite/Gabbro/Anorthosite

(Foid)-bearingDiorite/Gabbro

60

(Foid)olites

Quartzolite

Granite Grano-diorite

A P

F

60

Define Tonalite,

Monzonite,

Syenite based on this.

International Union of Geological Sciences

Don’t use “foid” in a

rock name. Use the

actual Feldspathoid

mineral name

IUGS Classification of

PhaneriticIgneous Rocks

Q

A chemical classification of volcanics based on total alkalis vs. silica. After Le Bas et al.

(1986) J. Petrol., 27, 745-750. Oxford University Press.

Cla

ssif

icat

ion

of

Ap

han

itic

Ign

eou

s R

ock

s

A classification and nomenclature of volcanic

rocks. After IUGS. From your text: An

Introduction to Igneous and Metamorphic

Petrology, John Winter, Prentice Hall.

Define Dacite, Trachyte, Latite

and Phonolite and Tephrite

based on this

Classification of Aphanitic Igneous Rocks

(foid)-bearingTrachyte

(foid)-bearingLatite

(foid)-bearingAndesite/Basalt

(Foid)ites

10

60 60

35 65

10

20 20

60 60

F

A P

Q

Rhyolite Dacite

Trachyte Latite Andesite/Basalt

Phonolite Tephrite

Figure 2-5. Classification of the pyroclastic rocks. a. Based on type of material. After Pettijohn

(1975) Sedimentary Rocks, Harper & Row, and Schmid (1981) Geology, 9, 40-43. b. Based on the

size of the material. After Fisher (1966) Earth Sci. Rev., 1, 287-298. From your text: An

Introduction to Igneous and Metamorphic Petrology, John Winter, Prentice Hall.

Classification of Pyroclastic Igneous Rocks

Peridotite

Andesite

Komatiite

Classification of Volcaniclastic rocks and sedimentsPyroclastic deposit

Clast size in mm PyroclastPrimarily unconsolidated: tephra

Primarily consolidated: pyroclastic rock

> 64 mm Bomb, blockAgglomerate, bed of blocks or bomb, block tephra

Agglomerate, pyroclastic breccia

64 to 2 mm LapillusLayer, bed of lapilli or lapilli tephra

Lapilli tuff

2 to 1/16 mm Coarse ash grain Coarse ash Coarse (ash tuff)

< 1/16 mmFine ash grain (dust grain)

Fine ash (dust)Fine (ash) tuff (dust tuff)

Mate

rial gunung a

pi pro

duk

letu

san (vide

Com

potn

, 1985)

<2mm

2-64mm

>64mm

Obsidian

Pumice

Scoria

See You….Soon