AGU

Every year the American Geophysical Union (AGU) hosts a conference which gathers more geoscientists into one place than any other event in the world (more than 24,000 geoscientists attend every year).  This week-long conference allows geoscientists from around the world to present their research, hear about the latest cutting edge research being done, and talk with other geoscientists, some of whom are the leaders in their field.  Last year I attended for the first time and was awed by the enormous amount of research presented.  This year I got to present some of my own.

The poster hall.  Every day 3,000 are presented for the entirety of the conference (15,000 total!)

On the floor of the poster hall.  Presenting research in this format allows for casual conversation with others and lets us gain new insights, receive critiques, and ask questions.    

Me at my poster.  Of the people that talked to me about my work 3 of them were anonymous judges for a student presentation competition   

In addition to posters nearly 7,000 lectures are given throughout the week.  This one, given by Secretary of the Interior Sally Jewell, was on the importance of making science understandable to the public.   

The exhibition hall is a place where vendors can show off their scientific equipment 

NASAs booth is always one of the most popular.  In addition to giving talks on their projects they also have interactive displays which showcase their many scientific accomplishments.  Their free calendars are also in high demand! 

I had an amazing time at the conference.  I was able to talk to other scientists about their research, listen to amazing talks, and learn new things about both my field of study as well as ones I'm not as familiar with.  A big highlight for me was watching two scientists with previously opposing views give back-to-back lectures during which they were able to solve the differences in their research.  Already can't wait for next year!     

  

Drinking Planets

A few weekends ago UCLA hosted Exploring Your Universe, a one day science fair aimed at getting students K-12 excited about science.  Dozens of booths with demonstrations and experiments were set up by the Physics, Chemistry, Astronomy, Biology, Atmospheric, and Geology Departments.  While the Mineral Physics lab didn't host a booth this year I volunteered at a booth hosted by another lab in the geology department, the SPINlab.

The SPINlab studies how fluids move within planetary bodies and their atmospheres. Because planets rotate about their axis it can be difficult to predict how liquids, like the outer core of Earth or the dense atmosphere of Jupiter will behave.  In comes the SPINlab which uses rotating tanks of liquids to model these effects.  You can learn more about the SPINlab and see videos of their experiments at: http://spinlab.ess.ucla.edu

While the SPINlab had a variety of amazing demonstrations (which can be seen on their website!) I volunteered at their Drinkable Planet demonstration.  At this booth we were teaching planetary differentiation in a rather unconventional way: with juice!

Every planet in the solar system today has layers, but in the very beginning of the solar system when planets were forming they were a jumble.  However, as time passed planets started differentiating (or separating) based on the densities of the different rocks.  The densest, heaviest rocks were pulled down by gravity to the center of the Earth while lighter ones stayed on the surface.  That's why we have a core made of iron and other heavy metals, a mantle of medium density metals and nonmetals, and a crust of mostly light nonmetals (this is an over simplification!).

Turns our freshly blended juice acts the same way.  The juice will sink to the bottom, the pulp will rise to the center, and the frothy foam will float to the top.  Armed with two juicers and $200 worth of fruits and vegetables we made fresh juice for hundreds of kids demonstrating how the mixture would separate with time, just like a planet.  We then encouraged the kids to watch and see for themselves before drinking their planet.  

 

Setting up the drinkable planet station

A differentiated cup of juice with light foam on the top, medium pulp in the middle, and heavy juice on the bottom

Mineral Physics

The center of the Earth lies 6,353-6,384 kilometers (3,947-3,968 miles) beneath your feet.  Depending on where you live (and more specifically the altitude), if you were to travel there you would have to pass through 0-40 km of crust, 660 km of upper mantle, 2,200 km of lower mantle (which, despite popular belief, is not molten), 2,080 km of outer core (which is molten), and 1,390 km of solid inner core.  Despite knowing this, no one has ever traveled to the center of the earth.  The deepest we have ever drilled is a mere 15 km and the deepest rock samples we have only come from a depth of 400 km.  So how do we know so much about the interior of our Earth?

My quick guide to the deep Earth

It turns out earthquakes are able to tell us a lot about the deep Earth. While earthquakes only occur in the upper 750 km of the Earth, the waves they generate can travel all the way to the core.  As these waves move through Earth’s layers they speed up, slow down, or rebound depending on the density of the layer.  This allows seismologists (geologists who study earthquakes) to measure the thicknesses and densities of the layers based on the speed of the wave.     

While this is a good start to understanding the interior of the Earth there are still many mysteries that remain.  We don’t know the exact composition of the different layers or how they might interact.  In fact, the 5 layer model of the Earth described above is an oversimplification.  There are other structures that exist within the Earth but are poorly understood such as the D” layer near the core-mantle boundary and the large low shear velocity provinces (LLSVPs) in the lower mantle.  Seismologists can show these features exist but can’t explain why.

That's where mineral physics come in.  Mineral physics is a relatively new branch of geology that falls under geochemistry and geophysics.  It studies the material properties of minerals at the high pressures and temperatures found within the Earth.  Because we can't measure these conditions directly we use lab experiments that simulate these conditions instead.  In my own research I use powerful lasers to create the high temperatures found within Earth and diamond anvil cells (DACs) to create the high pressures.  As the name suggests, a DAC uses two diamonds, similar to those found in jewelry, with the pointy ends facing each other.  Samples are placed on the tip of the diamonds which are then squeezed together to generate high pressures.  Using this method, we can create pressures exceeding 200 billion pascals which roughly correlates to the very center of the Earth (just one billion pascals is roughly equivalent to nearly 5 miles of cars stacked on top of each other).   

A loaded DAC, this one is at 53 billion pascals (note penny for scale)

An unloaded DAC with diamonds (mounted on a metal backing plate in center front) taken out

One of our diamonds under the microscope

These techniques have given us special insight into the composition and physical properties of the interior of our Earth.  Experiments have discovered a phase transition in an abundant mineral in the lower mantle at the same pressures and temperatures as the D" layer.  Because a phase transition changes the structure and therefore the density of the mineral it can explain why we observe a change in seismic velocities near the D" layer. 

Experiments also allow us to study how elements cycle through our Earth such as carbon, oxygen, hydrogen, nitrogen, and sulfur.  High pressure and temperature studies of minerals containing these elements tell us where in the Earth they might be stable, what phase transitions they might undergo, how much might be stored within the Earth, how much enters the deep Earth, and how much is released every year.  During my undergraduate research I studied the mineral Anglesite (which contains sulfur) at high pressures.  We currently don't know how much sulfur is in the deep Earth but it is estimated to contain around 90% of Earth's total.  My experiments found two phase transitions in Anglesite which made it more stable at high pressures.  However, there is still a lot of research to be done before we completely understand how sulfur and other elements cycle through our Earth so stay tuned for more about my current research!

A sample of Anglesite.  For my experiments a microscopic piece was broken off to load into the DAC 

Gem-O-Rama

This month I had the opportunity to meet up with some friends and visit Searles Dry Lakebed in Southern California for the 75^th annual Gem-O-Rama.  Gem-O-Rama is a two day gem and mineral collecting festival hosted by the Searles Lake Gem and Mineral Society every year during the 2^nd weekend in October.  During this event there are three field trips to collect rare and beautiful minerals from the lake bed.  My friends and I participated in all three of the trips and were able to collect some pretty cool stuff!

About Searles Dry Lakebed:

Searles Dry Lakebed is what remains of an ancient lake that existed during the last ice age.  The climate during this time was cooler and wetter causing many large lakes to form in the American southwest.  Because of the geologic formations in this area the lakes had no outlet rivers to take water out of the lake.  With no outlet rivers to ‘flush’ the lakes they became very concentrated in certain minerals, especially salts, which were dissolved in the water.  Later, when the climate became hot and dry again, the lakes evaporated leaving the minerals behind.  In the case of Searles Dry Lakebed, the conditions were perfect to form a variety of amazing mineral specimens.  Today, the lake bed is mined by Searles Valley Minerals for these minerals which are used in a wide range of common items such as detergents, glass, cosmetics, anti-fungals, fire-retardants, and fiberglass.  Once a year, for Gem-O-Rama, the mining company allows participants onto the lakebed to collect their own minerals.

View from the lakebed 

The Mud Field Trip:

For the first field trip almost 200 tons of sticky black mud are dug up from 10-20 feet below the surface of the lakebed and spread out into piles on the surface.  The 800 participants then get to dig through the mud looking for mainly Hanksite among a few other minerals.
 

People from all over the world come out for Gem-O-Rama.  Searles Dry Lakebed is where Hanksite was first discovered and is only found in a few other locations in the world.

My friends searching through the mud for crystals. 

The mud makes it hard to tell if you have a good specimen.  However, you can’t simply wash them off with water.  Because they’re a type of salt they end up dissolving! In order to clean them you have to use brine.

Troughs of brine are available to wash off specimens. 

Hanksite, which is a sodium potassium carbonate sulfate chlorite, is shaped like a cylindrical hexagon with two hexagon pyramids on each end.    

The Hanksite found here is called ‘barrel’ Hanksite because it looks like a barrel.

The Blow Hole Field Trip:

A week before this field trip multiple holes are drilled 25 to 40 feet below the surface of the lake bed and explosives are set to loosen the minerals making it easier to bring them to the surface.  A couple days before the trip pumps are used to bring the brine containing the minerals up to the surface and are spread out for participants to search for Hanksite, Sulphohalite, Borax, Halite, and Trona. 

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Pumping the brine and minerals to the surface.

Searching through the debris.

Close-up of the debris, can you spot anything cool?

The Hanksite from this depth is called ‘doubly terminated’ because the two pyramids on the end terminate at a point

Sulphohalite is another mineral that was first discovered at Searles Dry Lakebed, it forms two pyramids

Borax, commonly used in detergent, reacts with air to form a chalky white coating over time.

Halite, also known as table salt, forms cubes.

Trona forms in large clumps of little ‘blades’.  If you ever participate in Gem-O-Rama be sure to wear gloves to prevent the Trona from cutting you! 

The Pink Halite Field Trip

During the final field trip there is only one mineral to be found and as the name suggests it’s pink Halite!  Halite, which is regularly clear, can be tinged pink by salt-loving bacteria that turns red when it dies.  This field trip is located at the south end of the lakebed where rain water from the previous winter collects.  The water (also known as brine) contains a lot of dissolved salt and is the perfect home for salt-loving bacteria.  During the summer the water evaporates making the water saltier and saltier. Eventually, the bacteria die turning the water red.  At the same time large salt crystals begin to grow around the edges of the brine pools, like ice on a lake.  The salt incorporates some of the dead bacteria turning it pink.    

The best crystals are found on the bottom side of the salty crust that covers the brine pools, it can be hard work to break through!

After some trial and error we finally found a good pool.

Pink Halite, like regular Halite, grows in cubes but sometimes the crystals aren’t well formed because they grow very quickly.

If you like rocks and ever get the opportunity to go to Gem-O-Rama I would definitely recommend it! My friends and I had a blast and were able to add a bunch of new minerals to our collections.  Even if you aren’t a geologist or don’t know what you’re doing there’s sure to be someone who will be more than happy to give you pointers.  Plus, no matter your age or experience, you’re almost guaranteed to find something cool!  Be prepared to get dirty and have a lot of fun!  I also want to give a huge thank you to Searles Lake Gem and Mineral Society and Searles Valley Minerals for all the work they put into making this happen! 

What is Geology?

Geology.  Some have referred to it as the “Kardashians of Science”.  Others know it as an easy way to fulfill their science general education requirement in college.  But what is geology?  I feel that many people don’t fully understand what geology is.  Many people think of it as simply the study of rocks, which, while partially true, is not the whole story.

Geology, also known as Earth Science or Geoscience, is the study of our Earth.  This includes a wide variety of topics such as:

-          Seismology, the study of earthquakes.  Seismologists use field study and computer modeling to understand where and why earthquakes occur and how they travel through the earth.  This allows them to predict the locations and magnitudes of future earthquakes which can be used to create safety guidelines for high-risk areas.

-          Field Geology, the study of the relationships between different rock types in a natural setting through observation and mapping. Field Geologists spend time in the field making maps of the locations of different rocks.  These maps can be used to locate mineral resources or understand the geologic evolution of an area.  With the technology available today field geologists can also use satellite images and drones to be more effective.

      

  

Here are some pictures from my field geology class, on the left is the area I was studying and on the right is the map I made.

-          Hydrology, the study of the movement of water through Earth.  Hydrologists use modeling and direct observations to understand the movement of water above and below ground.  Using these tools they can make predictions about how much water is present in an area and how fast and far it will travel.  This information is especially helpful in times of drought or during a chemical spill that could affect drinking water.     

During my hydrology class field trip we installed seepage meters to determine how fast water was draining out of this pond.

-          Geochemistry, the study of the chemistry of rocks and minerals.  Geochemists study the chemical make-up of rocks, minerals, and even magma to understand their physical properties.  Using this information they can explain how a rock formed, what temperature it will melt at, and how it will cycle through the earth.   

-          Glaciology, the study of large-scale ice on earth.  Glaciologists use field study, imaging, and modeling to understand how ice formed, moves, and melts.  Their work often gives them the opportunity to spend time in the arctic or even Antarctica!    

-          Structural Geology, the study of how rocks deform.  Structural geologists use field study and physics to determine how rocks have been squeezed, folded, or fractured during their existence.  Structural geology has been able to explain how mountains form and tectonic plates move. 

My structural geology class took a weeklong trip to Death Valley to study how the valley and surrounding mountains formed.

-          Geophysics, the study of the physics that control Earth.  Geophysics use math, physics, and modeling to try and understand the Earth’s magnetic field, the convection of heat and material inside Earth’s mantle, and the structure of the interior of the Earth.    

-          Geomorphology, the study of land features and how they form.  Geomorphologists study the properties and evolution of features present on the surface of the Earth.  They try to understand how hills form, rivers move, and mountains erode.  Using this information they can make predictions about natural hazards such as landslides and floods.    

In my geomorphology class we studied how rivers transport sediments.  It was the middle of January and the professor lectured us for two hours while we were standing in this river! Brrrr!

-          Geochronology, the study of determining ages of rocks.  Geochronologists use field work to obtain their samples and then lab work to determine how old they are.  They have a variety of techniques to determine ages which have been used to date significant events in Earth’s history.   

-          Paleoclimatology, the study of Earth’s climate in the past.  Paleoclimatologists use biology, chemistry, and modeling to understand how climate has changed over Earth’s history.  To do this they study anything that might have recorded past conditions such as gas bubbles in ice or tiny fossils on the sea floor.      

This list covers only some of the topics that fall under geology.  Some fields of study include a combination of two or more. For example, my own area of study, mineral physics, is a combination of both geophysics and geochemistry.  This means that geoscientists need to understand a variety of different sciences such as math, chemistry, physics, and sometimes even biology to do our work.  The principles we use don’t only apply to the Earth, they apply throughout the Universe.  This allows geoscientists to study other objects in our Solar System.  For example, a geomorphologist can look at a picture of a landform taken by a rover on Mars, compare it to a similar feature on Earth, and by understanding how the feature on Earth was formed can determine similar processes are likely responsible for the feature on Mars.  This had led to the belief that in the past there was actively flowing water. We call this application of geosciences on other objects in our solar system Planetary Science.

Geology is a complex and diverse science that uses many different fields to understand the past, present and future of our Earth other bodies in our solar system.  You can bet you’ll find a geoscientist pondering the many mysteries of our home: from how the molten outer core churns to the causes of a landslide all the way to how the frozen plains on the dwarf planet Pluto formed.  If you’re interested in the processes that shape our planet and others then geology might be for you!

Welcome!

Hi Everyone! Welcome to Geology Jots!

My name is Krista and I am a 1^st year geology graduate student at UCLA.  Geology Jots is a place where I share my experiences as a young graduate student and my love for the science of geology.  This blog has three goals which are:

-          To inform and excite the public about an often overlooked science.

-          To document life as a graduate student

-          To inspire people (especially young women and girls) to get engaged in STEM (science, technology, engineering, and math) fields.

I became interested in geology when I was very young.  For as long as I can remember I have loved to collect rocks, wondering what they were made of and how they formed.  In 3^rd grade I presented a science fair project on the rock cycle.  Despite this, geology was not always an obvious path for me. I encountered many preconceived notions which almost prevented me from being where I am today.  I almost didn’t major in geology because a teacher in high school discouraged me from taking classes in the subject stating geology wasn’t a ‘real’ science.  It wasn’t until I happened to take a geology class my freshman year of college (the class I had wanted to take was full) that I realized how wrong my high school teacher was.  Geology was complex and fascinating and I was excited to study it.  Once I realized this I encountered another problem.  Geology required chemistry, physics, and math.  I constantly struggled in math leading teachers, classmates, my parents, and even myself to believe I simply wasn’t a math or science person.  Guidance from a geophysics professor showed me that nobody is born with an ability or inability to do well in subjects like math.  They are skills that need to be practiced and learned.  With this new mindset I became more open-minded about learning and relished the challenges presented to me in classes.  As I approached my final year I found I wanted to learn more, especially about the unsolved mysteries of the interior of the earth.  I began thinking about graduate school.  However, I was afraid I didn’t have what it takes to pursue a PhD.  Support from my classmates and advisers encouraged me to give it a try anyway and here I am today!  I hope that by sharing my experiences I can disprove  the assumptions I faced and create a clearer path for young scientists.        

I look forward to sharing my adventures with you!