Riffle, Pool, Riffle, Water bottle, Pool…

Um, yeah, so I was doing stream classification on a gutter the other morning. Why? Because I was. For reasons known only to water and whoever laid this section of gutter, there’s a fifty foot or so section that has a very nice riffle-pool sequence much like an ideal stream reach, complete with knickpoint and thalweg.


OK. Rewind a bit. When hydrology-types describe streams, creeks, brooks, rivers, bayous to each other, we use some in-field jargon and a numerical classification system developed by a gent named Dave Rosgen (who studied under Luna Leopold, the son of Aldo Leopold.). Streams [bodies of flowing water of any size] have certain characteristics no matter what the stream looks like. There are shallow areas with obstructions called riffles, deeper areas where the water flows more smoothly called pools, and a center of the active channel called the thalweg. Places where bedrock controls erosion (often marked by a waterfall of some kind) are knickpoints. Continue reading



Ever wonder where the word comes from? In English it generally refers to harsh language and behavior, occasionally to the “sal vitriol” once used in chemistry and medicine. I got to see where the original vitriol came from, and inadvertently learned more about medieval hazmat than I’d planned. You see, vitriol is a substance that was used for dyes. It is iron, zinc, or copper sulfate hydrate. And it looks really cool when it is behind glass, or turning mine galleries and shafts different colors. Just don’t touch it. It can be poisonous, and makes sulfuric acid before you precipitate it. Continue reading


It is rather common for thunderstorms to cause forest and range fires. Lightning flashes down from the cloud, smites a tree or some dry grass, and foomp! Call in Smokey the Bear! What is less common, especially with grass fires, is for the fire to create a storm. That happened out here, last week.

It was impressive. It was awful in both meanings of the word. Continue reading

Too Little, Too Late, or Geology 1: Moche 0?

Coastal Peru is not the easiest place to make a living. Imagine what the residents of the coastal cities must have thought as rumors of the rise of a new conquering people filtered down from the Andes highlands, just as the irrigation system the city of Chan Chan depended on began to fail. The gods must have been very angry. Something had to be done.


20/20 hindsight reveals that the sacrifices were in vain. The cities were abandoned and the Inca conquered the region. The people of the coastal cities disappeared without a trace, at least as far as the Spanish chroniclers were concerned, although the Spanish and later treasure-hunters dug in Chan Chan and carried off lots and lots of gold and silver ornaments and artifacts. The Chimu reappeared in the published accounts after WWII when archaeologists started looking away from the Inca. They had succeeded for several hundred years, had very sophisticated cities and societies, and then collapsed before 1500. What happened? Continue reading

May Day and Grass Fire Follow-up

Yes, it is either the International Day of Labor, which interestingly enough started in Chicago as part of the Pullman Strikes and the Haymarket Massacre/bombing/terror-attack by police (historians are still arguing over that one), or the day to give small flower arrangements to ladies of your acquaintance. Neither tradition seems to be practiced too much in the US, since we shifted Labor Day to late August, and tussie-mussies and other tokens of esteem have disappeared.

So this post is a follow-up to the little grass-fire that happened this past winter not far from where I work.

Bunches of bunch-grass. They will re-sprout in late spring.


Continue reading

Proving the Null Hypothesis – Cardio Version

One of the most under-valued things in science is proving the null hypotheses. The Null Hypothesis states that if you do X, nothing will happen. There will be no reaction, the bacteria won’t respond to the drug, the rat won’t get cancer, the mineral will not fluoresce. Everyone wants their experiment or test to do something, but often proving the null hypothesis is as, if not more, important than making a lab-rat turn plaid and start dancing the hora.

Last, week I decided that I needed to test a null hypothesis, cardiovascular version. Continue reading