This post summarizes a publication in the journal Nature (note paywall): Biggin, A.J., Piispa, E.J., Pesonen, L.J., Holme, R., Paterson, G.A., Veikkolainen, T., and Tauxe, L., 2015, Palaeomagnetic field intensity variations suggest Mesoproterozoic inner-core nucleation: Nature, v. 526, no. 7572, p. 245–248, doi: 10.1038/nature15523. Earlier this month, an article about the age of Earth’s inner core made […]
paleomagnetism
Reversals, Part 2
I’m finally getting back to the blog after about a week of frantic magnetometry (we discovered a bug in our magnetometer software, because of which we had to measure lots of stuff all over again!) and report-writing. Here is another in my reverse-color series on magnetic reversals.
Basics of Magnetism 4: Reversals Part 1
Earth has a magnetic field, which is what keeps your compass lined up with the North Pole [1]. The Earth’s outer core generates that magnetic field. You may have heard before that Earth’s magnetic field has, in the past, switched its North and South Poles. This is true, and kind of amazing and mysterious, but useful […]
Lab Equipment on the Drill Ship
I spend about 12 hours in the lab most of the days I’m at sea [1]. So do most of the other scientists on board. Sometimes we get a little silly talking about our lab equipment after (or during) our shifts. Right now the lab is kind of quiet, waiting for cores to come up from our […]
How sediments get magnetized
We are currently drilling through a big pile of mud and sand on the seafloor (the biggest such pile of mud and sand in the world), and I’m spending most of my day sitting next to the “silver bullet” in this photo:If you can’t see the sign in the photo, this is the superconducting rock […]
How we get cores
The JOIDES Resolution is a ship made to recover hundreds of meters of rock or mud cores from miles below the ocean. This amazing feat is accomplished by a huge crew and one big drill. To understand what we’re trying to do out here, it helps to know how the drilling works.The tower-like structure on the […]
Basics of Magnetism 2: The Geodynamo
Here’s the second in a series that explains the basic ideas in paleo-, geo-, and rock magnetism. I’m hoping to separate the real-life mysteries and wonder from the jargon that sometimes makes magnets seem like magic tricks. Have a question about any of these posts? Or about any aspect of paleomagnetism? I’d love to hear it. […]
Basics of Magnetism 1: Compasses
When I tell people that I study the history of Earth’s magnetic field, I get a bit self-conscious – as if I just told someone I specialize in Santa Claus. Geologists call us “paleomagicians” for a reason. You can’t see magnetic fields. You can’t touch them. Unlike most geological stuff, nothing obvious happens if you […]
How to go to sea as a paleomagnetist, part 2
What? You really wanted to know how I got picked to go to sea?You might say it was Facebook.Last spring, the Facebook page for the drillship JOIDES Resolution (“the JR”) posted a call for a paleomagnetist from the US to sail on an expedition to the Bengal Fan. Since that description fits me (and not that […]