# 24.10.17 earth science: earthquakes and tsunamis

<div id="bkmrk-as-plates-move-past-">As plates move past each other, they create fault lines (cracks)  
Three types: slip faults (side to side) and transform (vertical) faults (normal-falling or thrusting-rising)</div><div class="sandbox" id="bkmrk-unavailable-apple-wi"><div id="bkmrk-unavailable-apple-wi-1"><div id="bkmrk-unavailable-apple-wi-2"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file 56d358e5-45ad-41e3-9f3c-259a9bf87f81.

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The San Andreas Fault caused the 1906 quake, which moved 7 meters (22 feet) in one slip and devastated San Francisco:<div id="bkmrk--2">  
</div><div class="sandbox" id="bkmrk-unavailable-apple-wi-3"><div id="bkmrk-unavailable-apple-wi-4"><div id="bkmrk-unavailable-apple-wi-5"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file 2b3f7dc6-e157-4813-8361-eb11c1abd135.

</div></div></div></div></div></div></div>What the San Andreas Fault looks like from the air:  
<div class="sandbox" id="bkmrk-unavailable-apple-wi-6"><div id="bkmrk-unavailable-apple-wi-7"><div id="bkmrk-unavailable-apple-wi-8"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file e8acad8a-75be-4616-83e3-0ff3a16cd657.

</div></div></div></div></div></div></div><div id="bkmrk-thrust-%28vertical%29-fa">Thrust (vertical) faults caused the Bali quake and tsunami: (look this up on youtube)</div><div class="sandbox" id="bkmrk-unavailable-apple-wi-9"><div id="bkmrk-unavailable-apple-wi-10"><div id="bkmrk-unavailable-apple-wi-11"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file 98889bdd-01e0-44e7-a029-37cd87996365.

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Remember earthquake waves:<div id="bkmrk-p-and-s-waves%3A%C2%A0">P and S waves: </div><div class="sandbox" id="bkmrk-unavailable-apple-wi-12"><div id="bkmrk-unavailable-apple-wi-13"><div id="bkmrk-unavailable-apple-wi-14"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file eeb76c65-bccf-4c43-a01d-090db05b2094.

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<div id="bkmrk-p-waves-are-faster-t">P waves are faster than S waves:</div><div class="sandbox" id="bkmrk-unavailable-apple-wi-15"><div id="bkmrk-unavailable-apple-wi-16"><div id="bkmrk-unavailable-apple-wi-17"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file ca82e1e9-ec84-410c-aa8d-63326990d1a7.

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<div id="bkmrk-we-can-use-this-diff">We can use this difference to calculate epicenter (surface location) and hypocenter (actual center under the surface):  
</div><div id="bkmrk-recall-epidermis-is-">Recall epidermis is your skin (epi=top, dermis = skin), a hypodermic needle goes under (hypo) your skin (dermis)</div><div class="sandbox" id="bkmrk-unavailable-apple-wi-18"><div id="bkmrk-unavailable-apple-wi-19"><div id="bkmrk-unavailable-apple-wi-20"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file d5b8ceb6-8f8b-4966-ab67-82037088e413.

</div></div></div></div></div></div></div><div class="sandbox" id="bkmrk-unavailable-apple-wi-21"><div id="bkmrk-unavailable-apple-wi-22"><div id="bkmrk-unavailable-apple-wi-23"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file fa3ad1b6-aa92-43f1-a440-3ca85be1588c.

</div></div></div></div></div></div></div>AP exam question:<div id="bkmrk-how-much-stronger-is">

- How much stronger is a magnitude 7 quake than a magnitude 6?
- 7 to 5?
- 7 to 4?

</div><div id="bkmrk-more-on-tsunamis%3A%C2%A0nu"><span style="font-weight: bold;">More on tsunamis: </span>  

- Nuuanu slide: Look up on Wikipedia, how big was the tsunami, where and when?
- What is our biggest tsunami threat now?
- Where did the 1946 and 1960 Hilo tsunamis come from?
- Why is this important to you?

</div><div class="sandbox" id="bkmrk-unavailable-apple-wi-24"><div id="bkmrk-unavailable-apple-wi-25"><div id="bkmrk-unavailable-apple-wi-26"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file 6e74d04b-97da-4be8-87ae-157351f17d76.

</div></div></div></div></div></div></div>Check this out:

- Why would anyone living east of the interstate-5 corridor be concerned?
- Look at the dates on this diagram:

<div class="sandbox" id="bkmrk-unavailable-apple-wi-27"><div id="bkmrk-unavailable-apple-wi-28"><div id="bkmrk-unavailable-apple-wi-29"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file e8c58914-2121-4f19-ba81-955430770540.

</div></div></div></div></div></div></div>Historic data shows subduction zone quakes that would create a tsunami 1000' high or more on the Pacific northwest coast, flooding everything west of I-5.<div id="bkmrk--11">  
</div>Here's how we know what is going on to form the Andes:  
<div class="sandbox" id="bkmrk-unavailable-apple-wi-30"><div id="bkmrk-unavailable-apple-wi-31"><div id="bkmrk-unavailable-apple-wi-32"><div><div class="container"><div class="frontside"><div class="iframe">**Unavailable Apple Wiki media:** the exported data did not include file f7c38b5a-d1f9-4250-80a8-56417aa83f4e.

</div></div></div></div></div></div></div>Look at all of the earthquakes (red dots) as the plate subducts  
Two things to take-away about subduction zones:<div id="bkmrk-1.-subduction-zones-">1. subduction zones create ANDESITIC (pointy) volcanoes, which are high in silica, and sticky like thick pancake batter.  
2. subduction zones create lots of deep-focus earthquakes.  
  
</div><div id="bkmrk-play-time%3A"><span style="font-weight: bold;">Play time:</span></div>

- Look at the HPA Pacific Tsunami Warning Center (PTWC) seismograph here:[http://www.fdsn.org/networks/detail/PT/](http://www.fdsn.org/networks/detail/PT/)
- Look for the HPAH station-where is this?
- Why are the stairs to the nurse's office in such strange angles?
- Our Elab quake network here: [https://shakenet.raspberryshake.org/](https://shakenet.raspberryshake.org/)
- look for "station view" and zoom in
- jump in the elab, and see if R160F moves
- go into the monlab and find the same one
- why is it not showing up on the PTWC seismic sensor?
- why does your jumping NOT cause an alert?

- Hawaii quakes here:[https://earthquake.usgs.gov/earthquakes/map/?extent=-69.225,-230.44922&amp;extent=70.25945,-69.43359](https://earthquake.usgs.gov/earthquakes/map/?extent=-69.225,-230.44922&extent=70.25945,-69.43359)

<div id="bkmrk-click-on-some-earthq">  
Click on some earthquakes and note the depth and the seismic image.  
  
</div><div id="bkmrk-key-earth-science-po">Key earth science points:

- All elements up to Iron on the periodic table came from the big bang
- Earth was formed from materials created by first generation stars going supernova
- The core of the earth is made up of a rotating solid core surrounded by a liquid core
- The inner core creates our magnetic field, which reverses periodically
- Layers: crust-mantle-outer core-inner core
- Uranium in the core produces heat that travels to the surface by convection
- Tectonic plates on the surface move on top of the sticky asthenosphere because of this convection
- Spreading zones are were these plates are created, subduction zones are where they dive under others
- Subduction zones create trenches in the ocean and andesitic volcanoes (sticky lava, pointy cones)
- Hot spots in the crust can create basaltic volcanic islands like the one we are on (runny lava, broad cones)
- Earthquakes include P (primary, compression) waves and S (secondary, shear) waves
- P waves are faster and go through solids and liquids, S waves only travel through solids

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