TOPIC 1A - LITHOSPHERE 1.0 PDF

PCSHS Villa-Michelle P. de Vera Revised ppt for 2022 LCP Face to face classes June 2020 Week 1 Describe the distribution of active volcanoes, earthquake epicenters, and major mountain belts 36.1 (a)  36.1 TOPIC The Lithosphere Earth’s Interio...

PCSHS Villa-Michelle P. de Vera Revised ppt for 2022 LCP Face to face classes June 2020 Week 1 Describe the distribution of active volcanoes, earthquake epicenters, and major mountain belts 36.1 (a)  36.1 TOPIC The Lithosphere Earth’s Interior “  The Lithosphere The Lithosphere (Greek, Lithos for Stone) is the rigid, outermost layer crust and uppermost mantle. This makes up the “Plate” of Plate Tectonics.  Lithosphere core Cool, rigid, outermost layer of Earth that is divided into enormous pieces called tectonic plates; consists of the crust and the rigid uppermost part of the mantle.  Asthenosphere core The solid layer with plasticity in the upper mantle that is located just below the lithosphere; lithospheric plates “float” and move on this layer.  “ What are the differences between lithosphere and asthenosphere? LITHOSPHERE vs. ASTHENOSPHERE  “ TYPES OF LITHOSPHERE/CRUST  Characteristics of Oceanic and Continental Crust Characteristics and Comparison according to: Density Thickness Composition Geologic Age OCEANIC VS. CONTINENTAL CRUST DENSITY - OCEANIC CRUST IS DENSER THAN CONTINENTAL CRUST. - DENSITY: OC>CC  Why is oceanic crust denser than continental crust?? UNDERSTANDING DENSITY THICKNESS CRUST THICKNESS - CONTINENTAL CRUST (km) IS THICKER THAN OCEANIC 5-10 CONTINENTAL 25-70 OCEANIC CRUST. OCEANIC - THICKNESS: CC>OC CRUST 5-10 km CONTINENTAL CRUST 25-70 km  COMPOSITION CONTINENTAL OCEANIC ROCK TYPE Granite Basalt STATE Solid Solid ELEMENT Oxygen, Oxygen, Iron, COMPOSITION Sodium, Silicon, Silicon, Aluminum, Magnesium, Potassium Calcium (SiAl) (SiMa)  GEOLOGIC AGE - CONTINENTAL CRUST is OLDER than the OCEANIC CRUST OLDEST GEOLOGIC AGE CRUST OCEANIC 200 Million Years old CONTINENTAL 4 Billion Years old - GEOLOGIC AGE: CC>OC  TASK: OCEANIC CRUSTS ARE YOUNGER THAN THE CONTINENTAL CRUSTS. Can you tell why?  36.1 TOPIC Tectonic plates (Divisions of the Lithosphere)  Tectonic Plate A tectonic plate (also called lithospheric plate) is a massive, irregularly shaped slab of solid rock, generally composed of both continental and oceanic lithosphere. Plate size can vary greatly, from a few hundred to thousands of kilometers across. Plate thickness also varies greatly.  MAJOR PLATES any plate with an area greater than 20 million km2.  MINOR PLATES any plate with an area less than 20 million km2. MINOR PLATE SIZE (km2) NAZCA PLATE 15,600,000 km2 PHILIPPINE SEA PLATE 5,500,000 km2 SAUDI ARABIAN PLATE 5,000,000 km2 CARIBBEAN PLATE 3,300,000 km2 COCOS PLATE 2,900,000 km2 SCOTIA PLATE 1,600,000 km2 JUAN DE FUCA PLATE 250,000 km2 MICROPLATES These plates are often grouped with an adjacent principal plate on a tectonic plate world map. MICROPLATES These plates are often grouped with an adjacent principal plate on a tectonic plate world map.  36.1 TOPIC Scientific Basis For Dividing the Lithospheric Plates  “ What do you think are the bases scientists used in dividing Earth’s lithosphere into several plates?  “ ACTIVITY FIGURE 1 – DISTRIBUTION OF EARTHQUAKE EPICENTERS FIGURE 2 – DISTRIBUTION OF WORLD’S MAJOR MOUNTAIN BELTS FIGURE 3- DISTRIBUTION OF ACTIVE VOLCANOES Guide Questions (1/2 crosswise): 1. What can you say about the distribution of earthquake epicenters in the map? 2. Why is it important for us to identify the places which are prone to earthquakes? 3. Compare the location of majority of earthquake epicenters with the location of active volcanoes around the world. What can you infer regarding the comparison?  “ What do you think are the bases scientists used in dividing Earth’s lithosphere into several plates?  36.1 TOPIC Earthquakes and Seismic Wave Speeds Earthquakes... ❖ are sudden movement of of the ground EARTHQUAKE TERMINOLOGIES as a result of the release of stress ➔ epicenter build-up in the lithosphere. ➔ focus ❖ are happening very frequently, some ➔ magnitude are not that strong to be felt by ➔ intensity humans. ➔ seismic waves ❖ can be very devastating ➔ seismograph ➔ seismometer ➔ seismogram  SEISMOGRAPH SEISMOGRAM Which of the two body waves travel faster? BODY WAVES BODY WAVES SURFACE WAVES