Block 1 Geology Lesson 2 Rocks and Minerals Exploring Geosciences – February 13th, 2020 12 Thematic Lessons- Your Host: Francine Fallara, P. Geo., M.Sc.A (OGQ #433) Exploration geologist with over 25 years of field experience in various difficult geological environments Consultant in analytical data analysis specialized in complex geological exploration studies Expert in 3D geological modeling and www.ffexplore3d.com digital targeting of minerals Thematic Bloc 1 - Overview Thematic Block 1 Lesson Subtitle Date - 2020 English 1 Introduction to geology January 30th 1:30 - 3:30 PM 2 Rocks and Minerals February 13th 1:30 - 3:30 PM Geology 3 Rock Deformation February 27th 1:30 - 3:30 PM Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 3 Lesson 2 – Rocks and Minerals Lesson 2 Sub-lessons February 13th a. Intrusive rocks b. Volcanic rocks Types of Rocks 1:30 - 2:30 PM c. Sedimentary rocks d. Metamorphic rocks a. Classification Minerals 2:30 - 3:30 PM b. General composition Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 4 Types of Rocks Rocks are solid masses and classified into three fundamentally different types: Igneous rock Sedimentary rock Metamorphic rock https://www.911metallurgist.com/blog/classes-of-rocks Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 5 Types of Rocks: Igneous Rocks Igneous Rocks: General Description The Oldest types of rocks: Formed at depths within the Earth's crust, which slowly solidifies below the Earth's surface o May be later exposed by erosion Formed from magma* forced into older rocks Igneous intrusions form a variety of rock types. Known as the ‘Mother of all rocks’ Characterized as ‘Primary rocks’ Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 6 Types of Rocks: Igneous Rocks Igneous Rocks: What is Magma? Magma: Molten rock made by the partial melting of rocks in the earth's interior under conditions of high temperature and high pressure: o As rock melts, it becomes less dense and rises towards the earth's surface o Magma that reaches the earth's surface is called lava Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 7 Types of Rocks: Igneous Rocks Magma = Depth Lava = Subsurface https://gotbooks.miracosta.edu/earth_science/images/minerals.jpg Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 8 Types of Rocks: Igneous Rocks Igneous Rocks: Extrusive vs Intrusive? Volcanic vs Plutonic? Extrusive or Volcanic: Igneous rocks forming at the surface of the earth: o Example: Basalt is an extrusive igneous rock 1. Intrusive or Plutonic: Igneous rocks formed in depth, cools over long periods of time, develop larger crystals textures before it reaches the earth's surface: o Example: Granite Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 9 Types of Rocks – Geology of Quebec Rock Legend Intrusive 06) - Volcanic Sedimentary Thériault et Beauséjour,2012 (DV 2012 http://sigeom.mrnf.gouv.qc.ca/signet/classes/I1102_index Metamorphic MRN, 2013 (GT 2013-02) 10 Exploring Geosciences: B1-Geology: L2- Rocks and Minerals http://sigeom.mrnf.gouv.qc.ca/signet/classes/I1102_index Types of Rocks: Igneous Rocks - Quebec Rock Legend Intrusive Volcanic Sedimentary Metamorphic MRN 2013 (GT 2013-02) http://gq.mines.gouv.qc.ca/documents/EXAMINE/GT201302/ Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 11 Types of Rocks: Igneous Rocks - Quebec Common igneous rocks MRN 2013 (GT 2013-02) http://gq.mines.gouv.qc.ca/documents/EXAMINE/GT201302/ Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 12 Types of Rocks: Igneous Rocks - Quebec GRANITE An intrusive igneous felsic rock Contains a very high silica content Pink, red, gray or white in color with darker minerals Forms from slow crystallization of magma below the Earth’s surface Large grains visible with the eye Common igneous rocks https://www.123rf.com/stock-photo/granite_rock.html?oriSearch=rhyolite+rock&sti=mv0coqlbu8xgcdj200|&mediapopup=97965063 Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 13 Types of Rocks: Igneous Rocks - Quebec SYENITE An igneous rock that solidified slowly in the crust in a similar manner to granite Compositionally same as granite but the major difference is the absence or very low quantity of quartz Darker shades than granite Common igneous rocks https://www.123rf.com/stock-photo/syenite_rock.html?oriSearch=granite+rock&sti=mxyh5nqpc75kipmwx0|&mediapopup=138892320| Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 14 Types of Rocks: Igneous Rocks - Quebec GABBRO Intrusive igneous mafic rock Compositionally same as basalt but the major difference is the coarse-grained Shades of greenish gray to black colors Common igneous rocks https://www.123rf.com/stock-photo/gabbro_rock.html?oriSearch=syenite+rock&sti=m5kg001ntld5v4fts4|&mediapopup=89324496 Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 15 Types of Rocks: Volcanic Rocks Igneous Rocks: Extrusive vs Intrusive? Volcanic vs Plutonic? Extrusive or Volcanic: Igneous rocks form at the surface of the earth: o Example: Basalt is an extrusive igneous rock 2. Volcanic: Formed from lava from a volcanic eruption Volcanic rock and sediments created from magma erupted into the air are called "volcanoclastic" or “tuffs" and these are technically sedimentary rocks Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 16 Types of Rocks: Volcanic Rocks-Tuff Tuff: Rhyolite tuff formed during explosive volcanism TUFF Volcanic rock and sediments created from magma erupted into the air Called "volcanoclastic" or “tuffs" Are technically sedimentary rocks Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 17 Types of Rocks: Volcanic Rocks - Quebec Rock Legend Intrusive Volcanic Sedimentary Metamorphic MRN 2013 (GT 2013-02) http://gq.mines.gouv.qc.ca/documents/EXAMINE/GT201302/ Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 18 Types of Rocks: Volcanic Rocks -Quebec Common volcanic rocks MRN 2013 (GT 2013-02) http://gq.mines.gouv.qc.ca/documents/EXAMINE/GT201302/ Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 19 Types of Rocks: Volcanic Rocks -Quebec RHYOLITE An extrusive igneous felsic rock Contains a very high silica content Pink or gray in color Small grains difficult to observe by eye Common volcanic rocks https://www.123rf.com/stock-photo/rhyolite_rock.html?oriSearch=shale&sti=lpasg0b6cqefk2uo39| Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 20 Types of Rocks: Volcanic Rocks -Quebec BASALT Can be both an extrusive igneous mafic rock or an intrusive dyke Greenish gray to black in color Fine-grained Common volcanic rocks https://www.123rf.com/stock-photo/basalt.html?oriSearch=basalt+rock&sti=llhs1giv3e6lj59vqc| Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 21 Types of Rocks: Volcanic Rocks -Quebec KOMATIITE Rare extrusive igneous ultramafic rock derived from extremely hot magma Rapid cooling of the hot lava flows creates their "spinifex" texture Magnesium (Mg)- rich lava Low silicon, potassium and Common volcanic rocks aluminium content https://www.123rf.com/stock-photo/komatiite.html?oriSearch=basalt&prf=1&sti=my7s9c2rxx7eem833v|&mediapopup=115310611 Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 22 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Secondary Rocks? Why? Sedimentary rock is formed from the accumulation of small pieces of pre-existing rock: Parent rock Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 23 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Secondary Rocks Sedimentary rock is formed through the deposition and consolidation and solidification of sediments transported by fluids—including: water (rivers, lakes, and oceans) ice (glaciers) wind Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 24 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Solid particles vs Chemical? Two types of sedimentary rocks based on the source of the sediments: 1. Solid particles from weathered rocks: o Detritus particles: • Sandstone = Particles of sand from other rocks • Shale = Mud Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 25 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Solid particles vs Chemical? Two types of sedimentary rocks based on the source of the sediments: 2. Chemical sedimentary rocks: o Dissolved material carried to lakes and oceans: • Limestone = Calcite precipitation (i.e. evaporation) Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 26 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Erosional Processes Erosional processes grind down rocks into fragments and into smaller individual mineral grains: This materials is: o Transported and sorted by fluids o Coarser and finer fractions are naturally separated by density Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 27 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Deposition Sedimentary rocks are generally deposited in layers, and frequently contain fossils (plants and animals remains): Studies of sedimentary deposits reveal characteristics of the depositional environments at the time that the material accumulated This information can help tell the history of geologic events and climate change of an area Exploring Geosciences: B1-Geology: L2- Rocks and Minerals 28 Types of Rocks: Sedimentary Rocks Sedimentary Rocks: Solid particles vs Chemical? Joyce McBeth, Michael Cuggy, Karla Panchuk, Tim Prokopiuk, Lyndsay Hauber, & Sean Lacey Introductory Physical Geology Laboratory Manual, First Canadian Edition, Version 2, January 2019. Exploring Geosciences: