Earth's Rock Layers and Fossils Science Presentation PDF
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This presentation discusses the composition, formation, and distribution of rocks and minerals in the Philippines. It covers different rock types (igneous, sedimentary, and metamorphic), their properties (density, hardness), and the minerals that make up rocks. The presentation also highlights the distribution of minerals within the Philippines and the importance of conserving mineral resources.
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Good Day! Activity! Cross Puzzles Rocks & Minerals in Philippines Learning Outcomes At the end of the lesson, the student would able to; To Explain the composition and Formation of Solid Rocks To Identify the different minerals present in...
Good Day! Activity! Cross Puzzles Rocks & Minerals in Philippines Learning Outcomes At the end of the lesson, the student would able to; To Explain the composition and Formation of Solid Rocks To Identify the different minerals present in rocks and the distribution of minerals in the Philippines Introduction: Examining the mineral composition of rocks and their distribution is essential for both scientific research and practical applications, such as resource extraction environmental management Parts of the Lithosphere 1. The dense - CORE 2. The less dense - MANTLE 3. CRUST CORE centrally located solid mass of metal (inner core) and a liquid mass of iron and nickel (outer core). MANTLE a semi-solid magma layer consisting of iron, magnesium, and silicon. CRUST the outer layer of rock on which humans and animals live and plants grow. The crust is the light and very thin outer skin of the earth. NOTE: the crust does not have a uniform thickness. It is quite irregular: thinnest beneath the oceans and thickest at the continent. Scientists estimate WATERMELON that the irregular crust may range from 3 km thickness at the ocean floor to as much as 60 km at the mountainous portions of Earth continents. What solid materials can we find on earth? SOIL SAND ROCKS Geologists estimate that it takes about 100 years to produce 2.5 cm of soil. Beneath the soil is the layer of rock. However, it is less than 1% of the earth's thickness from the surface to the center Properties of ROCKS i the density of rocks The density of from the rocks found in oceanic continental crust is 2.9 g/cm'; crusts is approximately 2.8 g/cm the density The density of of rocks rocks found in from the oceanic continental crust is crusts is 2.9 g/cm'; approximately 2.8 g/cm rocks from deeper portions is 4.5 g/cm' Density is a measure of how much mass is packed into a given volume. It's calculated by dividing the mass of an object by its volume: Factors Affecting Rock Density 1. Mineral Composition 2. Pressure 3.Temperature 4.Porosity and Permeability Deeper Rocks and Density Crustal Rocks: Rocks found near the Earth's surface are typically less dense. They are made of lighter minerals like feldspar and quartz, and the pressure hasn't compressed them much. Deeper Rocks and Density Mantle Rocks: The mantle, located below the crust, is composed of denser rocks. These rocks are made of minerals like olivine and pyroxene, and the immense pressure has significantly compressed them. Deeper Rocks and Density Core Rocks: The Earth's core is made of extremely dense materials like iron and nickel. The extreme pressure and heat at the core have compressed these materials to incredibly high densities. Distribution in the Philippines Hmmm... Hmmm... IGNEOUS ROCKS Rocks in the Philippines *Zambales *Bataan *Laguna *Bay area *Bicol Region *Palawan *Sulu *Bukidnon- Lanao region *Cordillera *Sierra Madre mountain ranges SEDIMENTARY Rocks in the Philippines *Cagayan Valley *Central plain of Luzon *Montalban and Antipolo Rizal. METAMORPHIC Rocks in the Philippines *Northeastern Luzon *Mindoro *Palawan *Romblon *Western Mindanao Minerals in Rock Each crystal in rocks is actually a mineral. A rock consists of one or more different kinds of minerals. A substance is not called mineral unless it meets the following requirements. 1.) Minerals are inorganic 2.) They are formed in nature 3.) They are solids 4.) Atoms of a mineral have the same crystalline pattern 5.) The chemical composition is the same with only very minor change. A mineral as naturally- occurring, inorganic, crystalline solid, with a definite composition. Scientists have found and examined about 2000 different minerals. Only around 12 minerals however are common in the earth's crust. These minerals are called ROCK_FORMERS. Rock-formers They are responsible for most of the rock- formation in the Weathering Rocks earth's crust. Note that silicates make-up the largest group of minerals. The next largest group are the carbonates. Oxides are another important group of minerals; they are less common but industry needs/ many of the oxides. Carbonates Oxides Silicates Table 3.1 Rock Forming Minerals Figure 3.8 Table 3.2 Some Minerals with Metallic Lusters Table 3.3 Some Minerals with Nonmetallic Lusters Identifying Minerals Scientists have a systematic way of identifying minerals. More common minerals can be identified by their color or appearance. Other properties include, taste, smell, feel and sound when tapped. However, one can only be sure if he tests it. The physical properties of minerals that can be tested are: luster, hardness, streak, cleavage, fracture, color, specific gravity, and crystal form. 1. 1. LUSTER This refers to the way light is reflected from a mineral surface. Some minerals have metallic luster i.e. gold, silver, copper. Minerals with a nonmetallic luster are described as vitreous (glassy), pearly, silky, resinous, and earthy (dull). 2. Hardness A mineral's hardness measures its resistance to scratching. The Mohs Hardness Scale, created by Friedrich Mohs, ranks minerals from 1 (softest) to 10 (hardest). Minerals that don't scratch each other have the same hardness. Table 3.4 Moh’s Scale of Hardness 1. Talc 2. Gypsum Talc Calcite Flourite 3. Calcite 4. Flourite 5. Apatite Gypsum Apatite Table 3.4 Moh’s Scale of Hardness 6. Orthclase/ Fieldspar 7. Quartz Orthoclase Quartz Corundum 8. Topaz 9. Corundum 10. Diamond Topaz Diamond 3. Streak This refers to the color of the powdered mineral. To find the streak, rub the mineral. sample across a piece of unglazed porcelain or streak plate. You use this technique for minerals softer than porcelain or about 5 on the Moh scale. 4. Cleavage Cleavage is the tendency of a mineral to break along planes of weak bond- ing. The cleavage of a mineral is described by the number of planes exhibited and the angles at which they meet. Some minerals have several cleavage planes which produce smooth surface when broken, while others exhibit poor cleavage, and still others have no cleavage at all. 5. Fracture Minerals that do not exhibit cleavage are said to fracture when broken. Some break like glass, (conchoidal fracture), some break into splinters or fibers. 6. Color Color is important in the identification of only a few minerals. Such minerals are always of the same color, i.e., azurite is always deep blue, malachite is green; cinnabar is red; sulfur is yellow, etc. 7. Specific Gravity Specific gravity tells us how much heavier a mineral is compared to water. For example, Galena is 7.5 times heavier than the same amount of water. Most nonmetallic minerals have a specific gravity under 4. 8. Crystal Form When the external features of a mineral reflect its orderly internal arrangement of atoms, the mineral is demonstrating crystal form. When crystals start to form from a magma or solution, they interfere with one another. However, if a crystal is allowed to form without space restrictions, it will develop individual crystals. There are 6 common crystal systems. Table 3.5 Crystal Systems Minerals in the Philippines Nonmetallic minerals found in our country include : Dolomitic Limestone Silica Feldspar Clay Limestone is used to make lime, in concrete and cement. This is found in Cebu, in the eastern sides of Negros, and in Angat, Bulacan. Feldspar, used in making tiles and ceramic toiletware, abounds in Ilocos Norte and Pampanga. Silica, found in the alluvial sands of Palawan and silica rocks of Sagay, Negros Occidental, are principally used for making glass. Cebu, Ilocos Sur and Ilocos Norte have the red clay used for pottery. Kaolinite (white. clay) found in Iloilo and Camarines Sur is also used for pottery, ceramics and chinaware. Marble for building construction abounds in Romblon. Rich deposits of iron, nickel, copper, gold, silver, chromium, zinc, and lead have been located. A large part of Nonoc Island near Surigao del Norte has plenty of nickel deposits. Nickel Silver is not mined separately but as a by-product of mining gold or galena. Mercury reserves are located in Albay and Palawan, These deposits are often associated with diorite rock formations. Our biggest lead deposits are found in Ayala, Zamboanga City. The only platinum producer in the Diorite Rock country is Sta. Cruz, Zambales. Molybdenum deposits occur in Batangas, Camarines Norte and Negros Occidental. Conserving Our Minerals Resources The total volume of the earth's workable mineral deposits is only 1% of the crust. Research, especially in the discovery of more efficient processes, can prolong the lifespan of our minerals. Nature cannot replace the minerals we extract in just a short period of time. We will have to wait for millions of years once more. SUMMARY The solid earth or lithosphere consists of three parts: the dense core (outer and inner) the less dense mantle, and the light thin crust. Rocks exhibit different properties such as color, texture, hardness or brittleness, den- sity. SUMMARY Rock cycle refers to the process by which rock is changed from one class to another. The three rock types are igneous, sedimentary and metamorphic. The most common elements composing magma, aside from gases are: oxygen, silicon, aluminum, iron, calcium, potassium, sodium, and magnesium. SUMMARY Lava is similar to magma except that its gases have escaped. The two kinds of rocks formed when lava solidifies are: a) intrusive or plutonic rocks i.c., laccoliths and batholiths and b) extrusive or volcanic rocks. Igncous rocks may be classified according to texture: porphyry, glassy, vessicular. Activity Time!