Latitude and Longitude Lines STUDENT NOTES Date:

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1 Latitude and Longitude Lines STUDENT NOTES Date: Warm UP What do you know about navigating the ocean? What tools might you want to take along? How might they help you? Continents of Earth What are they? What percent of the Earth is land? List the seven continents from largest to smallest: Labeling Continents and Oceans Africa Antarctica Asia Australia Europe North America South America Artic Ocean Atlantic Ocean Indian Ocean Pacific Ocean Southern Ocean What are they? Oceans of Earth The 5 Oceans List the divided basins of the Earth. North and South, North and South,, The average ocean depth is larger than the average height of the continents above sea level. In the Northern Hemisphere, of the total area is ocean. Where in the Southern Hemisphere of the total area is ocean. : largest and deepest ocean. Contains the Mariana Trench : about have the size of the Pacific : found in the Southern Hemisphere : ¼ as deep compared to the others, smaller, contains sea ice : lower portion of the Earth (50 degrees South)

2 Compass Rose What is it? A compass rose is a design on a map that shows directions. It shows north, south, east, west, northeast, northwest, southeast, and southwest. Draw an E, S, and W on the compass rose to show East, South, and West. Add NE, SE, NW, and SW. What is the purpose of the latitude and longitude mapping system? Latitude Lines (Draw in diagram) AKA Which direction do they run? What is the name of 0 degrees Latitude? - Parallels above are called North Latitudes - Parallels below are called South Latitudes Longitude Lines (Draw in diagram) AKA Which direction do they run? Latitude/Longitude System is located on the longitude of the Royal Naval Observatory in Greenwich, England and is 0 degrees Longitude. Further Accuracy Degrees be subdivided into? 60 which can further be subdivided into 60. How are coordinates written? The cross point between one day and the next is 180 degrees which is the International Date Line. Hemispheric Symmetry Equator is a physical barrier. It can divide and. What occurs at the equator due to curvature? Circle what is found mostly in: - Northern Hemisphere: LAND WATER - Southern Hemisphere: LAND WATER Divide into NORTHERN and SOUTHERN Hemisphere EASTERN and WESTERN Hemisphere

3 Layers of the Earth STUDENT NOTES Date: Earth s Interior The earth is made up of layers that formed from different density. List the four from innermost layer of Earth to outermost layer. When was the Core discovered? Core is the innermost layer and is made of two sections and. Core What elements make up the core? Temperature of 5,500 C; estimated radius of 3470 km What percent of the Earth s mass is made of the core? volume? Inner Core- Discovered in 1936 Describe the components of the inner core. Inner and Outer Core 5000C; but new evidence suggests can get as hot as 6,600 C. How does this compare to the sun? 1,200 km thick with a density of 15 g/cm 3 Outer Core- Discovered in 1926 Describe the components outer core. What is the temperature range? 2,250 km thick with density of The mantle is the of the Earth. Mantle Which elements make up this portion of the Earth? 870 C to 2000C, 2,9000 km thick, Density- 5 g/cm 3 What percent of the Earth s mass is the mantle? volume?

4 Lower Mantle Extends from the outer core. Lower and Upper Mantle than the upper mantle and flows slower Upper Mantle Composed of two layers : partly melted and plastic - Plasticity: - Slowly flowing below the lithosphere extending to a depth of km; Density 3.5 g/cm 3 : Earth s cool rigid outer layer that is km thick -Made up of the rigid solid upper portion of the. Outermost layer. It is the of the Earth. Relatively cool temperature What percent of the crust is responsible for Earth s mass? volume? What elements make up the crust? Crust : Thin and made up of mostly basalt; 3-5 miles thick; denser than continental crust - What is basalt? : 25 miles thick and made up of mostly granite - What is granite? How are the Earth s layers similar to an egg? Analogy Shell= Egg= Yolk= Draw layers below.

5 Continental Drift STUDENT NOTES Date: Continental Drift Theory Which two scientists were the first noticed that the continents seemed to fit together like a puzzle?, German meteorologist, took it a step further with evidence and suggested that all continents had been joined in a single supercontinent. What is the name of this supercontinent? How did the continents change from this supercontinent to how they are today? 1. Shape of Continents: 2. Mountain Ranges: 3. Sequence of Rocks/Minerals: same rock patterns found in India, Africa, South America, Antarctica, and Australia 4. Fossil Evidence What is found on the coastlines of different continents? What is Glossopteris? - Since the seeds are too fragile to travel by sea and too heavy to travel suggest continental drift. Evidence to Support the Theory What is Lystrosaurus: Mesosaurus When do these fossils suggest Pangaea split into tow coontinents? - Upper half was Laurasia and lower half was Gondwanaland. 5. Glacial Evidence Which areas were involved in creation of glaciers during the same time? 6. Coal Deposits Where are similar coal deposits found? - This indicates that these areas were warmer since coal only forms from decaying plant matter in warm tropical conditions. What does tropical plant remains (coal deposits) suggest about Antarctica? 7. Salt Deposits: that are hundreds of millions of years old are found in location where these deposits do not form. 8. Limestone formation What does limestone form from? Why is it interesting to find limestone in the north-central US?

6 What piece was Wegener missing and couldn t explain to support this theory? Problems with the Theory Instead, he suggested that the continents plowed through the rock of the ocean floor. However, this idea was shown to be physically impossible. Wind and currents could possibly move fossils (to explain being found on other continents) What do we now know that provides an explanation for how they drift? Jigsaw puzzle had gaps If you include the it fills the gaps. Theory was NOT accepted by scientists. Wegener disappeared on an expedition to before his theory became widely accepted. With the video write down information about the alternative theory that contradicts the current accepted theory of continental drift. Other Theory

7 Continental Drift Theory. REJECTED!!!!! Seafloor Spreading STUDENT NOTES Date: Continental Drift Theory Wegener couldn t find any mechanism for how or why plates moved around the globe. But then. In 1947, researchers ( ) began mapping the ocean floor. What did he discover and map? The Thery of Seafloor Spreading In the 1960s, geologists Hess and Dietz hypothesized that. What happens as oceanic plates are pulled apart? New crust emerges as magma from the asthenosphere pushes up through the rift and solidifies into new crust. What does this new crust do to the old crust? As this theory became accepted, other scientists hypothesized that old sea floor subsides or sinks at As it is drawn downward by gravity and inertia (eventually it reaches the asthenosphere and melts into magma again). What speed is it similar to? 3 Forms of Evidence of Seafloor Spreading 1. Ocean Bottom Sediment Samples Cores samples from drilling showed that sediment layers were thin or absent at and thicker away from the ridges. Where can you find the thickest layers of sediment? 2. Radiometric Dating What is this used to determine? Using this method, scientists have found seafloor rock to be than continental rock and younger rocks near ridges and older rocks farther away. 3. Magnetometer Data What is an instrument that measures the polar orientation and magnetism of minerals called? In Earth s history, the magnetic polarity has flipped back and forth. These changes are recorded in. line up with switching magnetic poles, forming stripes, which showed new oceanic crust was being formed and pushed away from the rift valley. What does this symmetrical patterns in basalt (sea rock) show about the sea floor on either side of the mid-ocean ridge?

8 Intro Theory of Plate Tectonics STUDENT NOTES Date: Theory that explains how and why plates move. What two theories do plate tectonics unify by explaining how and why it happens? 1. The Earth s surface is covered by a series of. The Earth s lithosphere consists of more than a dozen separate plates: - What do these plates do? - Some plates are entirely ocean crust, some are entirely continental crust, and other plates are a combination. - What causes the plates to move? Man Features of Plate Tectonics 2. The ocean floors are constantly moving, spreading in the center and sinking at the edges and being regenerated. 3. What drives these convection currents? 4. Primarily, beneath the plates assist movement. The lower mantle is the asthenosphere and flows due to convection currents. Convection currents are caused by the very hot material at the deepest part of the mantle rising, then cooling and sinking again- --repeating this cycle over and over in vertical circulation of gas and/or liquid. What generally happens in respect to movement? Convection currents can be seen when you heat up substances, soup or water in a pan, and are able to move in the liquid. When the convection currents flow in the asthenosphere, what also moves? As molten rock rises and cool magma sinks, the crust gets a free ride with these currents. Convection currents in the mantle should be strong enough to. 5. Seafloor spreading can assist movement of the plates. Secondary driving force comes from seafloor spreading. - What happens as new seafloor forms? - What are the characteristics of the leading oldest oceanic plate? Types of Curst Forces of Plates Divergent Boundaries Oceanic vs. Continental Crust Oceanic Crust - Compared to the continental crust it is. - Oceanic crust lies lower on the mantle because of increased density. Continental Crust - Compared to the oceanic crust it is. - Continental crust rises higher above the mantle because of lesser density. Convection currents in the mantle produces 3 forces that move the crustal plates around and 3 types of boundaries = Divergent Boundary = Convergent Boundary = Transform Boundary Tension = AKA and build new crust The crust pulls apart and forms rift valleys and the Mid-Ocean Ridges How? Magma from the asthenosphere flows up through the rift valley creating new crust and widening the seafloor. What can occur at divergent boundaries? what can this create? Examples: Iceland, Hydrothermal vents, East African Rift, and Mid-Atlantic Ridge.

9 Compression = AKA and destroys old crust The crust collides to create mountains or subduction zone. : when one plate is pushed under another rplate and back into the mantle. What is formed at subduction zones? Ex: Japan. Convergent Boundaries 3 Types of Convergent Boundaries Oceanic-Oceanic Convergent: Oceanic plate colliding with oceanic plate - Which plate sinks? - What can occur here? - Ex: Marians Trench and Island Arch of Volcanoes Oceanic-Continental Convergent: Oceanic plate colliding with continental plate - Which plate sinks? - A trench forms as the plate moves down into the mantle. The plate melts. - What can occur here? - Ex: Caribbean Islands, Cascade Mountains in Washington, and Andes Mountains in S. America Continent-Continent Convergent: continental plate colliding with continental plate - What can occur here? Transform Boundary Pacific Ring of Fire and Hot Spots - Ex: Himalayas, Alps, Rockies, and ancient Appalachians Shearing: What happens at these boundaries? Can volcanoes occur? Earthquakes are common as rocks move when the plates slide Ex: San Andreas Fault in California is the boundary between the Pacific Plate moving north and the N. American Plate moving south What is it? Zones along the edge of the Pacific Ocean that has many. This horseshoe-shaped belt stretches about 25,000 miles. Hot Spot Theory The exception is (not at plate boundaries): Hot spots J. Tuzo Wilson observed that some volcanoes exist where? - He theorized that hot spots are small melting areas within the mantle where thermal plumes cause magma columns to push up through the crust (forming volcanoes or seamounts) Where can hot spots occur? - Ex: Yellowstone, Hawaiian Islands Do hot spots move with tectonic plates?. What happens? - This results in a line or chain of volcanic islands

10 Intro Seafloor Features STUDENT NOTES Date: Mapping the Oceans Cartography: - What is used to cap dry land forms? - What is uses SONAR to map underwater landforms? Geologic features on continents and the seafloor are created by tectonic activity at the boundaries between plates. Geologic Features Physical Features of the Seafloor Continental Margins : areas of the edges of the that are under water (4 subdivisions) Ocean Basins: The part of the ocean that is made primarily of basalt Continental Shelf A shallow extension of the continent that about 200 km and is really part of the continent even though it is under water. - What two types of characteristics can it be? They look like the continent from which they extend: hills and depressions The sediment on the shelf is eroded dirt and debris from the dry land above. - What is the sediment rich in? This is where most ocean life is found. Why? Continental Margins Continental Slope The transition at the edge of the continental shelf to deep-ocean floor. - The shelf break marks the transition - off the shelf where the ocean becomes very deep Continental Rise Where is continental rise found? - Formed by sediments that have been pushed down from the continental shelf and slope - This is where the continental crust ends and oceanic crust begins. - What can this be considered or thought of? Submarine Canyons These canyons cut into the continental shelf and slope, ending in a deep-sea fan. Sometimes they extend from the mouth of a river that drains and fast flowing water out to sea - What creates them? Sometimes they are created by earthquakes that cause an avalanche of sediment

11 Types of Margins Active Margins Sites of more intense geologic activity. What does this include? Characterized by, rocky shorelines, narrow continental shelves and steep continental slopes.example: West Coast of US Passive Margins Relatively inactive Characterized by, wide coastal plains, wide continental shelves and gradually sloping continental slopes Examples: East Coast of US Abyssal Plain These are the that extends seaward from the base of the continental slope. Covers about half of the deep-ocean basins Covered by a layer of sediment about 1 km thick. Abyssal Hill Hills less than 1000 m high on the abyssal plain (most are considered ) Mid-Ocean Ridges The on Earth. What is this associated with? What is created here by magma rising and pushing the plates apart? Forms underwater mountain ranges of volcanoes. Seamounts Underwater mountains, usually volcanic. The biggest mountain on Earth is Mauna Loa (HI). Seamounts build-up underwater over what? Ocean Basins When the seamount break the surface of the ocean, they turn into. Start to deflate and sink as the curst carries it away from the hot spot. Atolls What typically forms around islands? When the island deflates or descends back underwater and the coral reef is still intact, it turns into an atoll. Guyot, formed from being weathered flat when above sea level. Are the deflated seamounts/islands that have eroded and sank back underwater. (coral reef no longer present). Trenches Long, narrow, deep depression of the seafloor caused by. Deepest place on Earth is the - 7 miles deep. Volcanic Island

12 Marine Sediment STUDENT NOTES Date: Sediment: organic and inorganic particles that have accumulated together in a loose, consolidated form. Marine Sediment Origins of sediment include: weathering,, hard-shelled organisms,, volcanic activity, outer space Why study sediment? Sediments are important for Earth cycles. Which three includes sediment? They play a principle role in plate tectonics as the. Scientists use them to understand the Earth s past such as climate, ocean circulation patterns, biological development. List the three natural resources that can be found deep within ocean sediments. Studying Sedimentation : the study of sediment layers Scientists look for clues like rock composition, microfossils, deposition patterns, and use them to draw conclusions about the past : study of prehistoric oceans Study chemical ratios and radioactive isotopes found in microfossils to obtain evidence about. Types of Sediment What are the two most common ways to study sediments? 4 Origin Categoies: terrigenous/lithogenous, Biogenous, Hydrogenous, Cosmogenous How is size classified by? (AKA diameter of individual particles by the Wentworth Scale) Terrigenous/Lithogenous: 45% of all ocean floor sediments From weathering and erosion of rocks on continentals and islands. Where is this type of sediment primarily found? Ocean Sediments Biogenous: 55% of ocean floor sediments From siliceous and calcareous producing organisms ( ) that extract these compounds from the ocean water Hydrogenous: <1% of all ocean floor sediments From direct precipitation of sediment or minerals from seawater. What can this type of sediment form? Cosmogenous: extremely small amounts From atmosphere, meteorites, and dust

13 Classifying Sediment by Size Currents and waves tend to distribute sediments by size The by the motion of the water and therefore don t travel as fare as fine particles Generally larger, heavier particles settle first, lighter, smaller particles take longer to settle. : Process by which sediments are removed/transported - How does this occur? : Process by which sediments, soil, and rocks are added to a landform or land mass Atlantic vs. Pacific Atlantic has twice the sediment cover of the Pacific. Why? 1. : make it difficult for sediment to accumulate 2. : hard to get Terrigenous/Lithogenous sediments to mid-pacific 3. : Atlantic has more rivers emptying sediment into it.