P B G L T R O G O N I E A T U A I A P U U N N G [TGS7404] 2 SKS teori

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1 P B G L T R O G O N I E A T U A I A P U U N N G [TGS7404] 2 SKS teori
Semester 7, P T R B O G N E O I A T U A G I A P U U N N G [TGS7404] 2 SKS teori Dr. Hill. Gendoet Hartono

2 UTS UAS Rock Forming Mineral 1X Kimia Mineral Pembentuk Batuan 1X
PENDAHULUAN 1X Berisi tentang latarbelakang, bumi, batuan beku dan batuan gunung api, dan kedudukan di bidang geologi UTS TATAAN TEKTONIK 2X Berisi tentang tektonik global, regim tektonik, dan peranannya dalam magmatisme dan volkanisme GENERASI MAGMA 2X Berisi tentang magmatisme, diagram fase KLASIFIKASI 2X Klasifikasi magma atau afinitas magma Rock Forming Mineral 1X UAS Kimia Mineral Pembentuk Batuan 1X Petrologi Batuan Intrusi Dangkal 2X Petrologi Batuan Gunung Api 2X Alterasi Batuan Gunung Api 1X

3 KLASIFIKASI- 2

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6 Type of Magma Silica Content Gas Content Explosive-ness
Viscosity Silica Content Gas Content Explosive-ness Type of Volcano Example Low Basaltic 1-2% 50% Least Hawaii Shield Mt. St. Helens Andesitic Medium 3-4% 60% Medium Composite Rhyolitic High Cinder Cone 4-6% 70% Greatest Yellowstone

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8 The Classification of Igneous Rocks Into Suites
Igneous rocks are classified on several different criteria, including color, mineral composition, and chemistry. The classification based on igneous suites is a chemical classification. There are four major suites summarized in the table below. Igneous rocks are classified on several different criteria, including color, mineral composition, and chemistry. The classification based on igneous suites is a chemical classification.

9 Komatiite - An igneous suite distinguished by the presence of ultramafic lavas, including "noncumulate" rocks ranging in composition from peridotite to Basalt or andesite, and cumulate rocks ranging from peridotite to mafic Gabbros. The lavas commonly exhibit spinifex texture. All rocks of the series have low Ti and Fe/Fe+Mg, and high Mg, Ni, Cr. Ultramafic komatiites are restricted to the Archean and are associated with rifting centers.

10 Tholeiite - a silica-oversaturated Basalt, characterized by the presence of low-calcium Pyroxenes (orthopyroxene and/or pigeonite) in addition to clinopyroxene and calcic plagioclase. In contrast to the calcalkaline suite, these are iron enriched rocks. Tholeiites are characteristic of rifting sites and have shown up as enormous volcanic outpourings of flood Basalts (to 9 km thick and 1 200,000 km2) of predominantly Quartz-tholeiitic lava.

11 Calcalkaline - a series of igneous rocks in which the weight percentage of CaO = K20+Na20, and the weight percent of silica is between 56-61% (over-saturated). Includes many intermediate rocks (monzodiorite, Diorite, Quartz Monzonite, and Quartz Diorite, as well as many, but not all, Granites and Rhyolites). Calcalkaline rocks differ from Basaltic rocks by lacking a strong iron-enrichment. Calcalkaline rocks are one of three series of volcanic rocks generated along subduction zones and emplaced in volcanic arcs. Toward the trench they are replaced by tholeiitic rocks and away from the trench by alkaline rocks.

12 Alkalic - rock suites in which the total of alkali oxides (Na20+K20) exceeds that of Ca0 at a silica content less than 51% (undersaturated), of which alkali Basalts are the most important, but also including Syenites, nephaline Syenites, and phonolites (silica undersaturated, alkali feldspar and feldspathoid-rich analogues of Granites and Rhyolites). Alkaline suites occur in a wide variety of tectonic situations, including rifting centers (bimodal associations), subduction zones (both continental margin and island arc), oceanic islands (including hot spots such as Hawaii; alkali Basalts), strike-slip (transform), and within Proterozoic (but not Archean) stable Cratons independent of orogenic activity. They appear to be late fractionation stages in the evolution of magmas.

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21 See you..soon... See you..soon...