Shear Energy

So many tasks, so little time

Enter hat or juggling metaphor here…

While working on the development of Geology of National Parks, I’ve been gaining quite a bit of experience as a course developer. Even though this class is based on three traditional in-person classes, there is still a lot of work to do.

In just the last week, I’ve created figures, designed conceptual tutorials, organized the course management page, created…

I’ve decided to change the theme to my blog to shake things up (pun intended).

Hope you enjoy!

Dropbox Trick for accessing images

Using Dropbox to store files for webpages

One of the issue I came across while creating course content for Geology of National Parks was figuring out where to store images, pictures, screenshots, diagrams, etc. that I produced so that I could include them on webpages.  We are using Dropbox to share some of our files for the class and I was wondering if there was a way to create a folder for my…

Online course development = hard work and FUN!!

Recently, I’ve been helping to create an online class for the University of California. We are taking an existing course called Geology of National Parks and turning it into an online class that will eventually be offered UC-wide.

Creating this class is so fun – even if it does run my life at the moment. I get to learn all sorts of new technical skills like coding in HTML and CSS as well as video…

Making maps in the 21st century

Getting in touch with my inner cartographer

Often times, the best way to look at a catalog of earthquakes is by plotting their locations on a map. As a result, I get to spend lots of time making maps!

To create my maps and plot data, I use Generic Mapping Tools (GMT) an open-source toolset for creating plots. GMT is a set of command line tools that I can use to plot everything from simple x-y…

With the end of Daylight Savings last weekend, I am now entering into my third fall/winter season in 12 months. We’ve recently had some really fantastic weather in Santa Cruz, and I’ve been able to squeeze all my summer weather needs into a few short weeks.

Santa Cruz Sunset – 20 October 2014

Cold Water Classic – Steamers Lane, Santa Cruz

Rather than focus on the darker evenings (and an odd…

Silent but not so deadly

I know I haven’t updated in a while – things have been busy! I have a back log of posts I hope to get to over the next week, but thought I’d leave you with a few images of what has been keeping me so busy! Such is grad school!

Slow Slip Events — Silent Earthquakes

I’m modeling slow slip events off the east coast of the New Zealand’s North Island. Slow slip events are a type of earthquake that…

Science Post #3. Be sure to catch #1 and #2!

After the last post on faults, I got some great questions and thought I’d address them here. First off, apologies for the very short videos. Hopefully they were were useful in describing the 3 different types of faults. If not, let’s try again. While it may seem juvenile, it’s an activity I’ve done in university classrooms. Before the activity, we’ll…

Last night it got down to freezing which meant I opted for staying in bed rather than heading to the gym at 5:45 this morning. The walk to work was quite cold still – despite the 2 pairs of pants and 2 jackets! It used to be that when the temperature was freezing in winter, that meant we were having a bit of a warm spell! It seems like all my years of cold winters (I know…cold is relative) in…

Faults and Earthquakes

This is the second post in a series of Earth Science posts.

Faults are discontinuities or breaks in the Earth’s crust along which motion takes place. Faults occur in brittle regions of the crust where rocks deform by breaking.

It would be great if faults were all visible and obvious at the surface. Ideally, faults would all look like this:

San Gabriel Fault Photo Credit: M. D’Allessio

This surface…

A mountain with a view

After a week of rain and wind, the weather cleared up for the weekend and we had sunny skies. On Saturday, we decided to walk along the Southern Walkway to the Mt. Victoria. The summit of Mt. Vic offers stunning views of the city, Wellington Harbor, and the south coast.

Starting the Southern Walkway from Oriental Bay

  There are tons of cool views on the walk!

Scenes from Mt. Victoria

We wrapped…

Just got back from a quick break at the park across the street. Some people take smoke breaks, other take climbing breaks!

July 4th shenanigans

Challenge Accepted

Last weekend, I went to Taupo, a city located on a lake with the same name in the center of the North Island.

Google Maps Image

Taupo is a 5 hour bus ride from Wellington and the views along the way are beautiful! After driving along the Kapiti Coast (the south west coast of the North Island, we turned inland and stopped in Levin, Palmerston North, Taihape, and Tauranga.

My favorite part of the…

Earth Structure and Plate Tectonics

I’m re-blogging the first science post…

This post is going to be the first in a series of general science posts explaining why I’m studying earthquakes in New Zealand.

First, let’s start with a brief overview of plate tectonics, focusing on New Zealand.

  A Layered Earth:

The Earth is made up of many layers:

Inner Core – solid ball of iron and nickel

Outer Core – liquid iron that convects quickly

Now that I've gotten a few posts under my belt, I've decided to switch to the grown-up version of blogging websites. from now on, you'll be able to follow my blog at shearenergyblog.wordpress.com.

A true Kiwi continuous GPS station!

This post is going to be the first in a series of general science posts explaining why I'm studying earthquakes in New Zealand.

First, let's start with a brief overview of plate tectonics, focusing on New Zealand.

A Layered Earth:

The Earth is made up of many layers:

Inner Core -- solid ball of iron and nickel

Outer Core -- liquid iron that convects quickly

Mantle -- solid rock that convects over geologic timescales

Crust -- thin solid rocky surface (where we live!)

Near the Earth's surface, we further subdivide the Mantle and Crust into sub-layers:

Asthenosphere - Weak layer in the upper mantle ("asthenos" - weak). Ductile deformation (deforms without breaking)

Lithosphere - Contains the uppermost strong layer in the mantle ("lithos" - rocky) AND the crust. Brittle deformation (deforms by breaking)

The crust is further subdivided into oceanic and continental crust, which both have identifying properties:

Oceanic Crust - Thin, dark, heavy rock made primarily of basalt

Continental Crust - Thick, light (color and weight) rock made primarily of granite

Oceanic crust is denser than continental crust, which is why continental crust "floats" higher on the mantle. Density = mass/volume, so for rocks with equal volume, the denser rock is the heavier. This difference in rock type and density is why the oceans sit deep below sea level and the continents sit up above sea level.

Plate Tectonics:

The lithosphere is broken into many pieces of varying sizes called tectonic plates. These plates move around on top of the asthenosphere and interact with each other in different ways.

There are 3 types of tectonic plate boundaries:

Divergent - Plates moving apart. Crust is created at divergent boundaries. This is the most common type of boundary on Earth and is shown above by the saw-tooth lines. Example: Mid-Atlantic Ridge.

Convergent - Plates moving together. Crust is destroyed at convergent boundaries. Represented above by the lines with teeth on one side. Example: Himalayan Mountains, Subduction Zones

  Lateral - Plates moving past each other. Crust is neither created or destroyed at these boundaries. Represented above as straight lines connecting divergent and/or convergent boundaries. Example: San Andreas Fault

***To see short animations of each boundary type, go here.

New Zealand Tectonics:

New Zealand sits over a complex part of the boundary between the Pacific and Australian Plates.

Along the east coast of the North Island, the Pacific Plate subducts (sinks into the mantle) below the Australian Plate. This part of the boundary is called the Hikurangi Margin and is where my study area is located.

Moving south, the plate boundary turns into a lateral boundary in the form of the Alpine Fault, a strike-slip fault where the Pacific and Australian Plates are moving past each other. The Alpine Fault extends through much of the South Island until you reach Fiordland in the southwest corner.

Here, the plate boundary is yet again convergent, this time with the Australian Plate subducting beneath the Pacific Plate. This part of the boundary is called the Puysegur Margin

All of these changes occur within ~1600 km (~1000 miles), making New Zealand a great place to study phenomena associated with tectonic plate boundaries.