January 6, 1912: Continental Drift! “Beautiful is what we see, More beautiful is what we understand, Most beautiful is what we do not comprehend.” Anatomist and self-educated geologist Nicolaus Steno, 1673 January 6, 1912 the German meteorologist Alfred Wegener presented in a lecture entitled “Die Heraushebung der Großformen der Erdrinde (Kontinente und Ozeane) auf geophysikalischer Grundlage” (The uprising of large features of earth’s crust (Continents and Oceans) on geophysical basis) for the first time his hypothesis of the ancient supercontinent Pangaea, from which all modern continents split apart. Three years later he will publish his book “Entstehung der Kontinente und Ozeane“, translated in the third edition and published in 1922 as “The origin of continents and oceans.” Wegener didn’t propose something completely new; as he based his idea on earlier observations and suggestions, but in his work he had collected a broad array of evidence and his lectures initiated a fierce discussion in the scientific community.
Virtual Labs The links on this page are all VIRTUAL LABS offered by the Glencoe textbook company. These labs give the students the adventure of laboratory experimentation without costly supplies, worrisome environmental and safety issues, or time-consuming clean up. They are from all different areas of science: Biology, Physics, Genetics, Earth Science, Physical Science, and Chemistry. Please feel free to try these at home! Students will be directed to specific labs in class but there are over 100 labs offered here! To return to the home page, please click here: Faulting at Devils Slide The opening of the tunnel around Devil’s Slide in San Mateo County allowed for the creation of a mile-long trek to look at some of California’s fascinating geology. In my last geology hike to the trail, I took a photo of the great sedimentary layers at the north end of the trail, then edited the photo to show how well the strata line up on each side of a fault through the sediments. Mouse over the image below to see the image of the current conditions of the strata.
Wegener's Puzzling Evidence Exercise (6th Grade) Although Alfred Wegener was not the first to suggest that continents have moved about the Earth, his presentation of carefully compiled evidence for continental drift inspired decades of scientific debate. Wegener's evidence, in concert with compelling evidence provided by post World War II technology, eventually led to universal acceptance of the theory of Plate Tectonics in the scientific community. The following files are needed for this exercise and can be downloaded in pdf format (Teacher Overview, (For Teachers) Wegener's Key to Continental Positions for grade 6, Student Puzzle Pieces, Key to Wegener's Evidence sheet, and Student Map of the World Today). If students need additional hints beyond those provided below, there is a Puzzle Outline Hint to be used as a base for the puzzle. Objectives Students will observe and analyze scientific evidence used by Wegener.
Cascades Volcano Observatory Why Study Cascade Volcanoes? Cascade Range Active volcanoes dominate the skyline of the Pacific Northwest. The familiar snow-clad peaks of the Cascade Range are part of a 1,300 km (800 mi) chain of volcanoes, which extends from northern California to southern British Columbia. The volcanoes are the result of the slow slide of dense oceanic crust as it sinks beneath North America (subduction), which releases water and melts overlying rock. This rich volcanic zone contains the well-known landmark volcanoes and approximately 2,900 other known volcanic features ranging from small cinder cones to substantial shield volcanoes.
Earthquakes Living Lab: The Theory of Plate Tectonics Each TeachEngineering lesson or activity is correlated to one or more K-12 science, technology, engineering or math (STEM) educational standards. All 100,000+ K-12 STEM standards covered in TeachEngineering are collected, maintained and packaged by the Achievement Standard Network (ASN), a project of JES & Co. (www.jesandco.org). In the ASN, standards are hierarchically structured: first by source; e.g., by state; within source by type; e.g., science or mathematics; within type by subtype, then by grade, etc. Click on the standard groupings to explore this hierarchy as it applies to this document.
Cracking Up: Plate Tectonics, Volcanism, and the Structure of the Earth Model the structural layers of the Earth, investigate the data that led to the theory of plate tectonics, and discover the relationship between plate tectonics and earthquakes, volcanos, and mountains, through data analysis and hands-on activities. Preliminary Concepts Igneous: this rocks form as liquid magma or lava cools; the crystals that form are interlocking Metamorphic: this rock forms from existing (not molten) rocks under heat and/or pressure; the crystals are interlocking and have a preferred orientation Sedimentary: rocks are cemented together; not formed from crystals but from pieces or precipitants One common misconception is that layered rocks are always sedimentary; in fact, many metamorphic rocks are layered, and even a few igneous rocks can have layers.
Geologic Hazards Some volcanic eruptions are mild and slow, while others are powerful and dramatic. An eruption happens when magma, gases, or steam break through vents in the Earth's surface. A mild eruption may simply discharge steam and other gases, or quietly extrude lava. A strong eruption can consist of violent explosions that send great clouds of gas-laden debris into the atmosphere, or may consist of explosions that blast sideways from a collapsed portion of the volcano, as happened in the 1980 eruption of Mount St. Helens. Eruptions can alter the land and water locally through lava flows, lahars, pyroclastic flows, and landslides.
Drifting Continents Summary This activity is a teacher-led demonstration of continental drift and includes a math worksheet for students involving the calculation of continental drift over time. Students will understand what continental drift is, why it occurs, and how earthquakes occur because of it. Engineering Connection
Plate Tectonics Lesson Summary Overview According to the theory of plate tectonics, Earth's crust is composed of a number of individual plates that change shape and position over time. Geophysical evidence indicates that the face of Earth's surface has changed significantly since its initial formation and that the plates on which the continents are located are in constant motion. The movement of the plates is responsible for the formation of ocean basins, mountain ranges, islands, volcanoes, and earthquakes. Important concepts in the theory of plate tectonics include the following:
Ring of Fire The Ring of Fire is a string of volcanoes and sites of seismic activity, or earthquakes, around the edges of the Pacific Ocean. The Ring of Fire isnt quite a circular ring. Its shaped more like a 40,000-kilometer (25,000-mile) horseshoe. JOIDES Resolution - Ocean Drilling Research Vessel The first three activitie s below are variations on the theme of ages of the basement rock spreading outward from the mid-Atlantic Ridge as determined by Deep Sea Drilling Project scientists with samples of microfossils taken by RV Glomar Challenger in 1968. Plate Tectonics - Earth Like a Puzzle - Children learn about plate tectonics, earthquakes, and volcanoes at this site in Scripps Institution of Oceanography by Nan Criqui Most people know that Earth is moving around the Sun and that it is constantly spinning. But did you know that the continents and oceans are moving across the surface of the planet? Volcanoes and earthquakes as well as mountain ranges and islands all are results of this movement. Less than 100 years ago, many scientists thought the continents always had been the same shape and in the same place. A few scientists noted that the eastern coastline of South America and the western coastline of Africa looked as if they could fit together.