Monday, January 28, 2008

Rock Haikus

They come from inside
They were molten, now they aren’t
They are igneous

Phaneritic rocks
Large crystals live in this kind
Visible crystals

Aphanitic rocks
Small crystals you cannot see
Small, like the aphid

Silica, felsic
Light color, low density
Continental Crust

Iron rich, mafic
Darker, higher density
Oceanic Crust

Igneous rocks have
many different names we learn
Vocab is a pain

Friday, January 11, 2008

And now for Box Models!

I’ve been set to the task of constructing a box model for my silica work in the North Pacific. A box model starts by thinking of your system as a 3 dimensional box, hence box model. Then you start adding up all the ways silica can enter your box and subtract from that all the ways silica can exit your box. Assuming that your box is in steady state (i.e.: there’s no tremendous buildup of silica in the box) then everything coming in has to equal everything going out. Simple, right?

Here’s my box model:Things going in = things going out. Now we get to apply numbers to this model and this is where I’m boned. The difference between choosing a number like 190 or 195 is a big deal in these calculations and to choose the right number means choosing the number my advisor can live with. I would storm on ahead and finish this already if only I knew that I wouldn’t have to do all this work over again once we decide that 192 is a more appropriate number than 193. And so, dear reader, such is the life of a graduate student. I guess we’ll have to find something else to do in the interim. Like read some science papers, but I’d rather watch baby monkey videos.

Tuesday, January 8, 2008

Sediments are so sedentary

Have YOU ever wondered how much sediment is dropped onto the seafloor in our world’s oceans? Have you ever wondered how it varies as you move away from the coasts? What’s that? You HAVEN’T!?? To be fair, I guess it’s not a topic one broaches on a daily basis, but today I’ve had to think a little about this question so I’ll tell you.

Sediments (i.e.: dirt, broken shells, fish poop, dead phytoplankton, and whatever else constitutes all the crap floating in the ocean) collect on the seafloor on the order of centimeters per thousands of years. That means that hardly anything makes it to the seafloor. Near the continent (land) we get a larger sedimentation rate, like a few millimeters per year in areas where junk is roaring out of rivers and where productivity in the surface waters is high. But out in the big, deep Pacific you’ll find maybe 2 or 3 centimeters of sediment accumulation for ONE THOUSAND YEARS. That means when you scoop up a sediment core, you’re looking tens of thousands of years into the past.

I had this idea while sifting through mud cores on our last expedition to bag up all the mud that we didn’t need and package it so as to sell it to fancy ladies for spa treatments. Could you imagine? People would eat that shit up. All I’d have to do is use lots of words like “vital” and “nutrients” and “exclusive” and “silky”. So long NSF, hello LancĂ´me. Not surprisingly, it was very nice mud. My hands were very soft after working in the lab for several grueling hours. I kick myself for not actually following through with this genius scheme.