GEOLOGY-1010 • • • • INSTRUCTOR’S NAME: MARK BASKARAN PHONE: 313-577-3262 E-MAIL: BASKARAN@WAYNE.EDU OFFICE HOURS: 10:30-11:30 AM-M,F Grading Policy – GEL-1010 • LECTURE AND LAB MUST BE SUCCESFULLY COMPLETED • FIRST QUIZ. • GRADING • EXAM #1=20% • EXAM #2=20% • FINAL =30% • LAB =30% COURSE GRADES WILL BE CURVED • EXAM WILL BE MULTIPLE CHOICE AND TRUE/FALSE • QUESTIONS • EXAM MATERIAL FROM LECTURE NOTES, DO NOT MISS LECTURES • MAKE UP EXAM ………………..ONLY ON VALID EXCUSES Lab OPEN LAB (MAY ATTEND ANYTIME WHEN LAB IS OPEN) INTEGRAL AND ESSENTIAL PART OF GEL 1010 COURSE OF FINAL GRADE – HELPS TO IMPROVE THE GRADE 30% LAB WILL START IN THE MUST SECOND WEEK HAVE PHOTO ID LABORATORY OUTLINE (BOOKSTORE OR MARWELL’S) MUST BE BROUGHT TO THE LAB – QUESTION QUIZ AT THE END OF EACH LAB (COMPUTER TESTING; QUIZ WILL CONSTITUTE THE GRADE FOR THE LAB) 20 *~ 3 HOURS – ALLOW 3.5 HOURS TO COMPLETE LAB AND QUIZ *NO FOOD/DRINK ALLOWED; NO VISITORS ALLOWED *NO LAB MAKEUPS *LOWEST LAB WILL BE DROPPED.TOTAL 13 LABS – 1 DROP = 12 LABS 4 OR MORE LABS MISSING-MUST DROP THE COURSE UNOFFICIAL WITHDRAWAL WILL BE GIVEN *LAB STARTS ON TUESDAYS- ENDS THURSDAYMUST BE TAKEN THE SAME WEEK TIPS FOR SUCCESS READ OUTLINE PRIOR COMING TO THE LAB REVIEW MATERIAL IN TEXT BOOK RELATED TO THE LAB TOPIC FILL IN OUTLINE CAREFULLY AS IT WILL BE YOUR STUDY GUIDE FOR THE QUIZ ASK LAB INSTRUCTOR IF THE LAB MATERIAL IS UNCLEAR. Methods of Science • DATA GATHERING • HYPOTHESES ( LOGICAL AND TENTATIVE EXPLANATION ) ( > 50 HYPOTHESIS FOR ICE AGES ) • THEORIES ( GENERALLY ACCEPTED EXPLANATIONS) • LAWS, SCIENTIFIC ( THEORY THAT MEETS RIGOROUS TESTING) • GEOLOGICAL MODELS Scientific Theory • MASSIVE VOLCANIC ERUPTIONS OF INDIA’S DECCAN PLATEAU• --------CLOUD OF V. ASH & GAS – COOLING – DECLINE IN VEGETATION – PLANT EATING ANIMALS WOULD HAVE DIED – MEAT EATERS DEATH • METEORITE IMPACT THEORY - ~ 10 KM DIAMETER CRASHED INTO THE EARTH – DUST VEIL & SMOKES FROM FIRE BLOCKED SUNLIGHT Extinction of Dinosaurs • 65 M YEARS AGO, 75% OF ALL FORMS OF LIFE VANISHED ( LAND & WATER – DWELLING) • EPEDEMIC DISEASES ELIMINATED DINOSAUR POPULATION? • EGG STEALING- MAMMALS RAVAGED DINOSAUR’S NESTS? • OCEANS BECAME LETHALLY SALTY – WHY SOME MARINE ORGANISMS SURVIVED? • DRASTIC ENVIRONMENTAL CHANGE? • SHIFT IN PLANET’S PROTECTIVE MAGNETIC FIELD?( ALLOWING HARMFUL RADIATION) EVIDENCES • *1” – CLAYEY LAYER ~ 65 M YEAR • CLAY CONTAINS IRIDIUM ( ABUNDANT IN METEORITE; RARE IN INT. ROCKS) ( ABOVE THE LAYER ~ ONE FOURTH AS MANY SPECIES) • *PRESENCE OF TEKTITES ( GLASSY SPHERES ) IN SEDIMENT LAYERS AROUND THE WORLD ( SUPER HEATED ROCKS AT IMPACT SITE HURLED INTO THE AIR IN A MOLTEN STATE) • *FOSSILS ABOVE & BELOW THIS 1” Evidences – contd. • *HIGH CONC. OF CARBON SOOT WITHIN THE IRIDIUM LAYER ( EVIDENCE OF GLOBAL WILD FIRE) *WHITISH FOSSIL – RICH LAYER AT THE BOTTOM OF A CORE (ODP) IN ATLANTIC OCEAN – OVERLAIN BY A THIN GRAY – GREEN LAYER OF IMPACT DEBRIS TOPPED BY AN IRON – RICH BAND – FOSSIL POOR LAYER ABOVE. *IMPACT SITE – YUCATAN’S CHICXULUB CRATER 300 KM DIAMETER. Big Bang Theory •TIMING ESTIMATED USING HUBBLE SPACE TELESCOPE -CURRENT POSITIONS & SPEED OF VISIBLE GALAXIES AS THEY MOVE FROM ONE ANOTHER •AFTER BIG BANG, UNIVERSE BEGAN TO EXPAND & COOL •FEW MINUTES AFTER BIG BANG, UNIVERSE COOLED BY ABOUT •ONLY PROTONS, NEUTRONS & ELECTRONS PRESENT • ATOMS (BUILDING BLOCKS OF MATTER) •ONLY WHEB UNIVERSE COOLED ~ 3000 DEG CENTIGRADE, •H, He – LIGHT ELEMENTS BEGAN TO EXIST Big Bang Theory Lecture Outlines Physical Geology, 10/e Plummer, McGeary & Carlson Introducing Geology Physical Geology 10/e, Chapter 1 Plummer et al. Geology in Today’s World • Geology - The scientific study of the Earth – Physical Geology is the study of Earth’s materials, changes of the surface and interior of the Earth, and the forces that cause those changes • Practical Aspects of Geology – Natural resources – Geological hazards – Environmental protection Practical Aspects of Geology • Natural Resources – All manufactured objects depend on Earth’s resources – Localized concentrations of useful geological resources are mined or extracted – If it can’t be grown, it must be mined – Most resources are limited in quantity and non-renewable Damage from Northridge (CA) earthquake (1/17/1994) apartment-15 died Resource Extraction and Environmental Protection • Coal Mining – Careless mining can release acids into groundwater • Petroleum Resources – Removal, transportation and waste disposal can damage the environment Alaska pipeline • Dwindling resources can encourage disregard for ecological damage caused by extraction activities Geologic Hazards • Earthquakes – Shaking can damage buildings and break utility lines (electric, gas, water, sewer) • Volcanoes – Ash flows and mudflows can overwhelm populated areas • Landslides, floods, and wave erosion Geologic Hazards • Earthquakes – Shaking can damage buildings and break utility lines (electric, gas, water, sewer) • Volcanoes – Ash flows and mudflows can overwhelm populated areas • Landslides, floods, and wave erosion Geologic Hazards • Earthquakes – Shaking can damage buildings and break utility lines (electric, gas, water, sewer) • Volcanoes – Ash flows and mudflows can overwhelm populated areas • Landslides, floods, and wave erosion Physical Geology Concepts • Earth’s Systems – Atmosphere • – Hydrosphere (rivers, ocean, glaciers, lakes) • – water on or near the Earth’s surface Biosphere • – the gases that envelop the Earth all living or once-living materials Geosphere • the solid rocky Earth Physical Geology Concepts • Earth’s Heat Engines – External (energy from the Sun) • Primary driver of atmospheric (weather) and hydrospheric circulation • Controls weathering of rocks at Earth’s surface – Internal (heat moving from hot interior to cooler exterior) • Primary driver of most geospheric phenomena (volcanism, magmatism, tectonism) Earth’s Interior • Compositional Layers – Crust (~3-70 km thick) • Very thin outer rocky shell of Earth – Continental crust - thicker and less dense – Oceanic crust - thinner and more dense – Mantle (~2900 km thick) • Hot solid that flows slowly over time; Fe-, Mg-, Si-rich minerals – Core (~3400 km radius) • Outer core - metallic liquid; mostly iron • Inner core - metallic solid; mostly iron Earth’s Interior • Mechanical Layers – Lithosphere (~100 km thick) • Rigid/brittle outer shell of Earth • Composed of both crust and uppermost mantle • Makes up Earth’s tectonic “plates” – Asthenosphere • Plastic (capable of flow) zone on which the lithosphere “floats” Theory of Plate Tectonics • Continental Drift Hypothesis (Alfred Wagner) – Originally proposed in early 20th century to explain the “fit of continents”, common rock types and fossils across ocean basins, etc. – Insufficient evidence found for driving mechanism; hypothesis initially rejected • Plate Tectonics Theory – Originally proposed in the late 1960s – Included new understanding of the seafloor and explanation of driving force – Describes lithosphere as being broken into plates that are in motion – Explains origin and locations of such things as Tectonic Plate Boundaries • Divergent boundaries – Plates move apart – Magma rises, cools and forms new lithosphere – Typically expressed as mid-oceanic ridges • Transform boundaries – Plates slide past one another – Fault zones and earthquakes mark boundary – San Andreas fault in California • Convergent boundaries – Plates move toward each other – Mountain belts and volcanoes common – Oceanic plates may sink into mantle along a subduction zone, typically marked by a deep ocean trench Tectonic Plate Boundaries • Divergent boundaries – Plates move apart – Magma rises, cools and forms new lithosphere – Typically expressed as mid-oceanic ridges • Transform boundaries – Plates slide past one another – Fault zones and earthquakes mark boundary – San Andreas fault in California • Convergent boundaries – Plates move toward each other – Mountain belts and volcanoes common – Oceanic plates may sink into mantle along a subduction zone, typically marked by a deep ocean trench Plate Tectonics-contd. • Top of a plate – consisting of oceanic crust, continental crust or a part of each • North American Plate is moving westward relative to Europe – Plate’s divergent boundary is along midoceanic ridge in the North Atlantic Ocean • Transform Boundary: San Andreas Fault in CA is an example – Earthquakes along the fault are a product of motion • Convergent Plate Boundary: Less dense, more buoyant continental plate will override the denser, oceanic plate Geologic Time • “Deep” Time – Most geologic processes occur gradually over millions of years – Changes typically imperceptible over the span of a human lifetime – Current best estimate for age of Earth is ~4.55 billion years • Geologic Time and the History of Life – Complex life forms became abundant ~544 million years ago – Reptiles became abundant ~230 million years ago – Dinosaurs became extinct (along with many other organisms) ~65 million years ago – Humans have been around for only ~ 3 million years • “Nothing hurries geology” Mark Twain A Map of Tectonic Plates A Map of the Pacific Ocean Plate Rifting and Divergence Divergent Zones Oceanic Plate Subduction Key Points • • • • • • • • • Physical Geology Earth’s internal and external heat engines – driving factors Divisions of Earth’s layers Plate Tectonics – convergent, divergent, transform boundaries Crust – classification Age of the Earth and Universe Factors causing earthquakes Lithosphere Asthenosphere