No Vember 6, 2020

November 6, 2020Welcome to science class!

Friday, Nov. 6, 2020I can describe theobservations of AlfredWegener that led to his ideaof continental drift.

November 6, 2020Yá’át’ééh!sha'áłchíníWelcome to scienceclass!

August 27, 2020

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Announcements Earth Science textbooks are ready to be picked up at the school. This isthe book for the rest of the year. Get yours as soon as possible. Zoom Students! Pick up Zoom material for Q27:30am-4pm @ TMS Parent/Teacher Conferences - November 13 from 4-7pmSign up begins Monday, November 9 on the website

ectonics-rocks-minerals-Earth’s crust-continentalAgenda Kahoot! -ContinentsAnnouncementClass DiscussionReview VocabularyInteractive Plate TectonicsIndependent Work

ectonics-rocks-minerals-Earth’s crust-continentalAnnouncements Zoom Students!Pick up Zoom material for Q27:30am-4pm @ TMSTutoring- Thursday @ 6PMNovember 13th- Parent TeacherConference

ectonics-rocks-minerals-Earth’s crust-continentalClass DiscussionAccording to the continental drift hypothesis, thepresence of similar fossils in South America andAfrica supports which scientific idea?

ectonics-rocks-minerals-Earth’s crust-continentalStudent Friendly ObjectiveI can construct a model to explainhow the distribution of fossils androcks, continental shapes, andseafloor structures providesevidence of the past plate motions.

ectonics-rocks-minerals-Earth’s crust-continentalEssential Question(s)How is Earth’s surfaceconstantly changing?DOK2

A German scientist andmeteorologist. He is most notablefor his theory of continental drift,which he proposed in December1912. This was the idea that thecontinents were slowly driftingaround the Earth. He also hadideas about why the continentsdrift, which other scientists thoughtwere impossible. His hypothesiswas not accepted until the 1950s.Then several discoveries gaveevidence of continental drift, andof the actual causes.Alfred WegenerWegener, circa 1924–1930

continental drift: a hypothesis suggesting thatcontinents are in constant motion on the surface ofEarth

Pangaea (pan JEE uh):one supercontinentthat all the continentswere once part of

Evidence That Continents MoveWegener knew that he needed evidence to supporthis hypothesis of continental drift. The most obviousevidence was how the continents fit together likepieces of a puzzle. But other scientists were doubtfulof his hypothesis. Wegener needed more evidence.

Fossil CluesThere are many animals and plantsthat live only on one continent. Forexample, lions live in Africa but notin South America. Because oceansseparate the continents, animalscannot travel from one continentto another by natural means.However, fossils of similarorganisms have been discoveredon several continents that are nowseparated by oceans.Glossopteris (glahs AHP tur us)

Fossil CluesConsider Which ofthe continentswould not supportGlossopteris growthtoday?Glossopteris (glahs AHP tur us)

Climate Clues Coal beds are in Antarctica, a polar climate today. Yet coalformed from fossilized plants that lived long ago in warm, wetclimates. This meant that Antarctica must have been warmerand wetter when these plants were alive.Glaciers were studied by Wegener, he pieced Pangaea together,he proposed that South America, Africa, India, and Australiawere located closer to the South Pole 250 million years ago.

Climate CluesGlacial striations

Rock Clues The rock formations and mountain ranges seemed tohave formed in the same way at the same time. Geologists have studied rocks from these eruptions. Theyfound that the volcanic rocks from both continents wereidentical in chemistry and age.

Rock CluesWegener's EvidenceSimilar Rock LayersFound on DifferentContinents

Rock Clues Mountain Chains-More evidence came from the rocks that makeup two mountain chains in Europe and North America.

FINALLYThe evidence for driftingcontinents was hidden onthe seafloor. DuringWegener’s lifetime,scientists did not havethe tools to determinewhat happened beneaththe oceans. Wegener alsocould not have knownwhat the seafloor lookedlike. The evidence neededto prove continental driftwas not discovered untillong after Wegener’sdeath

Spreading of the SeafloorThe ocean depth is calculated byknowing how fast sound travels in thewater (approximately 1,500 meters persecond) and measuring the time ittakes the sound to travel to the bottomand return. This method of seafloormapping is called echosounding.

ectonics-rocks-minerals-Earth’s crust-continental

ectonics-rocks-minerals-Earth’s crust-continentalAssignmentOPTION 1: Cut the puzzlepieces from Zoom bag torecreate plate tectonics.OPTION 2: Complete webquestpart 1&2 on ClassDojoREMINDER: Rock Cycle is due!Upload it toClassDojoDUE: Friday, Nov. 6th

ectonics-rocks-minerals-Earth’s crust-continentalCheck Exit Ticket

Agenda AnnouncementsObjectiveEssential QuestionsVocabularyVideoLesson SlidesInteractive ActivityEXIT Ticket

Thursday, Nov. 5, 2020I can describe theobservations of AlfredWegener that led to his ideaof continental drift.

ESSENTIAL QUESTIONS1. Who was the scientist who studied theEarth’s continents? What did he propose?DOK22. Compare the past and present of theEarth’s continents? DOK2

VOCABULARYcontinentevidencefossilgeologisttheory

In science, a new idea has the power tochange everything we thought we knewabout our world. But how do scientistsprove that their new ideas are correct?Let’s look at how one scientist tried toprove his idea.

Scientists collect evidence, including objects they havefound and things they have observed, as part of theirresearch. Then, based on this evidence, they come upwith a theory that explains how something occurs—orhas occurred—in the natural world.Scientists use theories to explain everything from howthe universe began to why objects fall to the ground. In1915, German scientist Alfred Wegener published a bookto present a theory he called "continental drift."Wegener believed that the large pieces of land we callcontinents move over long periods of time. Even thoughWegener found strong evidence to support his theory,not everyone accepted it from the start.

GoalsHere are the big ideas we need to know:The continents are in slow butconstant motion, riding on top ofpieces of Earth's crust called tectonicplatesThe scientific community oftenrefuses to accept new scientifictheories that challenge existing onesScientists often use new evidence tobuild on other scientists’ work andstrengthen theoriesPangea over Time

VocabularyRead these words and their One of the large land masses on the Earth’ssurfaceThe objects or the information observed tosupport a hypothesisEvidence in rock form of previous lifeScientist who studies the history andstructure of the EarthAn explanation of real life occurrancessupported by lots of evidence

According to Wegener's theory, there was only onelarge continent 300 million years ago. He named thiscontinent Pangaea (from the Greek for "all the Earth,"and pronounced "pan-GEE-uh"). Pangaea then split,and its pieces drifted, or moved, apart over millions ofyears to form today's continents. In fact, thecontinents are still drifting today. This video showsWegener's evidence and explains the difficulty he hadgetting his ideas across to geologists—scientists whostudy the history and structure of Earth.Now show what you have learned so far aboutcontinental drift by answering these four questions.Wegener Video

What makes Continental Drift a Theory?1. All of the continents seem tofit together like a puzzleFloridaCurrent SouthAmericaCurrent Africa

What makes Continental Drift a Theory?2. The same fossils have beenfound across continents.

What makes Continental Drift a Theory?3. Glacial deposits have been found across the southernparts of South America, Africa, India, and Australia.

Scientists collect evidence, look for patterns in theevidence, and then test different ideas to explain thesepatterns. Only then do they put forth a theory. However,not every theory is accepted by other scientists.After reading the passage, write one to twosentences to answer the question below.As you read this passage, consider what Wegener wasunable to prove to other scientists that caused them toreject his ideas at first.What was the major weakness of Wegener'stheory of continental drift?Click to read Plate Tectonics—Proof That Wegener WasRight (PDF).

Marking TextSymbolDirectionNumber the paragraphs.Start with #1 and continue in order until the end of the text or reading assignment.Circle the number, leaving room in margins. Like page numbers, paragraphnumbers will act as a reference so you can easily refer to a specific section.Circle key terms, names of people, places, theories, and datesDraw a box around formulas, values, and units.Underline or highlight claims and relevant information, definitions, andevidence.

Proof That Wegener Was RightThe first scientific theory to suggest that Earth’s continents were once in different positions thanthey are now was Alfred Wegener’s theory of continental drift. Looking at a map of the world,Wegener noticed something that interested him: the east coast of South America and the westcoast of Africa looked like they might fit together like pieces in a puzzle. He then read about thework of some other scientists who suggested that South America and Africa were onceconnected by a strip of dry land called a land bridge.

Testing his ideaInspired by these findings, Wegener began looking for evidence to support his idea: that thecontinents were not fixed in place but rather had moved over time. Using evidence that includedmatching coastlines, shared rock and fossil types, and mountain ranges of the same age, heexplained that places that are today far away from one another were at one time connected.

Why scientists doubted himIn Wegener’s mind, he had proven his theory. However, few experts in the field of geology at thetime accepted that continents could move. After all, how could they push through Earth’s solidcrust? Because Wegener had not explained what caused the continents to move, his theory didnot receive much support while he was still alive.

New evidence answers questionsBy the late 1960s, a group of scientists had developed a new theory based on evidence that hadbeen collected since Wegener’s death in 1930. It answered questions that Wegener’s own theoryhad not. First, the scientists suggested that a transfer of heat caused the continents to move.This heat starts deep inside the Earth, rises to the surface, and returns underground in a circularpattern. The scientists also learned that Earth’s crust is constantly being created and destroyed.This explained what happens to the crust as the continents drift. According to the new theory,crust is created at underwater mountain ranges called mid-ocean ridges. Crust gets destroyed atdeep-ocean trenches, which are long and narrow ditches in the seafloor where pieces of crustare forced together.

Proof that Wegener was rightWith these new pieces of evidence, scientists explained the driving force behind continental driftthat had been missing from Wegener’s theory. By extending Wegener’s original ideas, we nowknow that our planet’s crust is broken into a dozen major pieces, called plates. Even though wemay not notice it, these plates are in constant motion—or drifting, as Wegener put it. The namegiven to the new and improved theory is “plate tectonics”—with “tectonics” being the study ofEarth’s structure.

When nceEvidenceSummaryReasoning

After reading the passage, write one to two sentences to answer the question below in CHAT.What was the major weakness of Wegener's theory of continental drift?