New User Special Price Expires in

Let's log you in.

Sign in with Facebook


Don't have a StudySoup account? Create one here!


Create a StudySoup account

Be part of our community, it's free to join!

Sign up with Facebook


Create your account
By creating an account you agree to StudySoup's terms and conditions and privacy policy

Already have a StudySoup account? Login here

EAR 105

by: Lucy Kassel

EAR 105 EAR 105 - M001

Lucy Kassel

Preview These Notes for FREE

Get a free preview of these Notes, just enter your email below.

Unlock Preview
Unlock Preview

Preview these materials now for free

Why put in your email? Get access to more of this material and other relevant free materials for your school

View Preview

About this Document

February 1, 2016 - February 3, 2016 Subjects: Plate Tectonics
Earth Science
L. Ivany
Class Notes
25 ?




Popular in Earth Science

Popular in Earth Sciences

This 4 page Class Notes was uploaded by Lucy Kassel on Saturday February 6, 2016. The Class Notes belongs to EAR 105 - M001 at Syracuse University taught by L. Ivany in Winter 2016. Since its upload, it has received 27 views. For similar materials see Earth Science in Earth Sciences at Syracuse University.


Reviews for EAR 105


Report this Material


What is Karma?


Karma is the currency of StudySoup.

You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!

Date Created: 02/06/16
February 1, 2015 Plate Tectonics and the structure of the Earth The Structure of Earth’s Interior ● Crust ● Mantle ● Inner Core ● Outer Core Crust ● Oceanic Crust ○ Basalt, dense, thin (­5 km) ● Continental Crust ○ Granite, lighter, thick, (­35­70 km) ● Moho (Mohorovicic discontinuity)  ○ separates crust from mantle ○ marks an increase in density ● Both kinds of crust “float” on the mantle because they are less dense ○ → Isostasy Isostasy ­ The Iceberg Effect ● Wood blocks (and icebergs) float because they are less dense than water ● Larger blocks sit higher, but have a deeper keel too ● Areas with thicker crust, like mountain belts, sit lower in the mantle (like bigger  icebergs float lower in the ocean) ● If you add weight to the crust (e.g. a glacier) it will float lower into the mantle Lithosphere ● Crust plus top of mantle ● rigid slabs ● Continental lithosphere is ­100­200 km thick Asthenosphere ● Upper mantle ● “tar”, flows Core ● Iron and nickel ● Inner is solid ● Outer is liquid ● Circulation of molten iron in the outer core generates Earth’s magnetic field What drives circulation in the outer core? ● Brand new research suggests that magnesium minerals are precipitating out of  the liquid outer core and rising, making remaining Fe­rich liquid more dense, driving  circulation Plate Tectonics ● the lithosphere is broken up into rigid plates that float on the asthenosphere and  slide past each other ● the continents are not fixed in place! Evolution of an idea... ● Alfred Wegener ● 1915 ● noticed that the continents fit pretty well if you push them together Continental Drift ● similar rock types were found on both sides of the suture ● similar fossils were found on both sides of the suture ● evidence for glaciers on all southern continents, but some are tropical now ● the reconstructions make sense! ● Pangaea­ a “supercontinent” ○ when the continents were all together forming one continent Evidence for Continental Drift ● Similar continental outlines ● Similar rock types ● Similar fossils ● Glacial deposits match up ● Paleoclimate reconstructions make more sense ● do you make it work? How can continents plow through ocean  crust??? Need a mechanism... ● So the idea languished... Then in the 1960s, we mapped the ocean floor...(Marie  Tharp [1920­2006]) ● Rocks get older as you move away from the ridge in either direction ­ symmetric ● Sea floor shows stripes of alternating magnetic polarity symmetric around the  ridge Sea­Floor Spreading ● Creation of new oceanic crust (basalt) at mid­atlantic ridges ● But... the Earth is not expanding ● If sea­floor spreading is correct, plates must be being destroyed somewhere also ● Where? ○ Trenches ■ Marianas Trench 35,798 ft deep! (10,911 m) ● Earthquake distribution is related... as is the distribution of volcanoes... Subduction ● Destruction of old crust ● Creation of new crust Plate Tectonics ● Lithosphere plates can contain both oceanic and continental crust February 3, 2015 Plate Tectonics ● Lithospheric plates can contain both oceanic and continental crust Plate Boundaries ● Transform­ sliding past each other ● Convergent­ coming together ● Divergent­ spreading apart 1) Divergent Plate Boundaries ● Sea floor spreading ● New crust is always basalt, from partial melting of the ultramafic  mantle due to decompression ● Why is there a ridge? ○ Young crust is hot, less dense, sits high ○ As crust cools, becomes more dense, contracts ○ Ex: Mid­Atlantic Ridge ■ comes to the surface of Iceland ● Ex: Earthquakes ○ generally small/not disastrous, and frequently  moving ● Rifting ○ spreading starts under a continent ○ Ex: East Africa 2) Convergent Plate Boundaries ● Two different types of crust, so three possibilities: ○ Oceanic­ oceanic ○ Oceanic­ continental ○ Continental­ continental  ● Ocean­ Ocean Convergence ○ Subduction of denser crust at the trench ○ melting of down­going slab, volcanism ○ creation of Island Arc ○ earthquake foci deeper away from trench ○ Ex: Japan is a classic island arc ○ Partial melting of downgoing slab and sediment­  only the lower­temperature minerals melt ○ Island arc rocks are therefore not quite as mafic ○ Probably how the continents were originally formed ● Oceanic ­ Continental Convergence ○ Subduction of oceanic slab at the trench ○ Volcanism and mountain building along edge of  continent ­ “active margin” ○ Ex: Andes Mountains ■ West Coast of South America ■ “Active margin” ○ Ex: Cascade Mountains: US Pacific Northwest ■ Mount St. Helens ● Continent ­ Continent Collision ○ Continents cannot be subducted ○ Intense deformation and mountain building during  collision ○ Ex: Himalayas (Mount Everest) ○ Ex: India ­ Asia collision ○ Ex: Folding in the Swiss Alps ○ Ex: Appalachians ■ Formation of Appalachians ● Much older collision,  about 250 mya (end of Paleozoic Era) ● Collision of North  America and Europe/ North Africa to make Pangea 3) Transform Plate Boundaries ● “strike­slip” motion sliding ● offsets in spreading ridges ● Ex: San Andreas Fault


Buy Material

Are you sure you want to buy this material for

25 Karma

Buy Material

BOOM! Enjoy Your Free Notes!

We've added these Notes to your profile, click here to view them now.


You're already Subscribed!

Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'

Why people love StudySoup

Jim McGreen Ohio University

"Knowing I can count on the Elite Notetaker in my class allows me to focus on what the professor is saying instead of just scribbling notes the whole time and falling behind."

Kyle Maynard Purdue

"When you're taking detailed notes and trying to help everyone else out in the class, it really helps you learn and understand the I made $280 on my first study guide!"

Steve Martinelli UC Los Angeles

"There's no way I would have passed my Organic Chemistry class this semester without the notes and study guides I got from StudySoup."


"Their 'Elite Notetakers' are making over $1,200/month in sales by creating high quality content that helps their classmates in a time of need."

Become an Elite Notetaker and start selling your notes online!

Refund Policy


All subscriptions to StudySoup are paid in full at the time of subscribing. To change your credit card information or to cancel your subscription, go to "Edit Settings". All credit card information will be available there. If you should decide to cancel your subscription, it will continue to be valid until the next payment period, as all payments for the current period were made in advance. For special circumstances, please email


StudySoup has more than 1 million course-specific study resources to help students study smarter. If you’re having trouble finding what you’re looking for, our customer support team can help you find what you need! Feel free to contact them here:

Recurring Subscriptions: If you have canceled your recurring subscription on the day of renewal and have not downloaded any documents, you may request a refund by submitting an email to

Satisfaction Guarantee: If you’re not satisfied with your subscription, you can contact us for further help. Contact must be made within 3 business days of your subscription purchase and your refund request will be subject for review.

Please Note: Refunds can never be provided more than 30 days after the initial purchase date regardless of your activity on the site.