planetwater

ground- water, geo- statistics, environmental- engineering, earth- science

Fiberglass Fluorimeter

Today was our first test using our fiberglass fluorimeters. They look very spectacular, don’t they? Unfortunately, the picture can’t capture the dynamics of the situation, which is created by the blinking lights. They appear to be constantly on on the photo.

The bad news is, that our first attempt of calibration curves looks really sucky. We’ll have to find away to improve those quickly!

Written by Claus

March 31st, 2011 at 7:33 am

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Written by Claus

March 30th, 2011 at 11:11 am

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Some Effects on Water and Statistics From the Recent Earthquake in Japan

This is a blog about water and statistics. Admittedly, in a very broad sense. Neither earthquakes nor related problems with nuclear power stations are at first glance directly related to these two topics. However, the earthquake was so strong that its consequences are felt widely. Even in groundwater wells in which the seismic waves from an earthquake induce water level fluctuations. This phenomenon has been pointed out both by the NGWA blog and by Dave Campagna at WaterWired

Image from WaterWired

If this earthquake has been felt by groundwater wells, it was really big. But how big? As theusrus.de points out, only one earthquake of the USGS data-set he used that contains all earthquakes since 1973, has been bigger.

The “size” of an earthquake is measured on the logarithmic Richter scale, which is used as the x-axis in the above histogram. The recent earthquake in Japan was linked with a value of 9.0 on the Richter scale. The earthquake in the Indian Ocean around christmas 2004 was the one that was bigger since the recent one in Japan, with a value of 9.3 on the Richter scale. The folks at Mathematica seem to have a little larger time series, which contains one more earthquake of magnitude bigger than 9.0 — it happened in 1964 in Alaska, USA. It’s always fun to look at something logarithmic on a linear scale:

The folks at Mathematica also have a nice map of where earthquakes happen, and great info on seismic waves and plate tectonics.

And finally, two visualizations of descriptive statistics:

–  xkcd has posted a nice graphic visualizing radiation dose units: what activity leads to which radiation exposure and how big is that dose compared to other activities

– IBM has produced a nice graphic showing the deaths per TWh by energy sources (nuclear energy is not the worst in that measure).

Written by Claus

March 26th, 2011 at 8:33 am

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Written by Claus

March 23rd, 2011 at 11:11 am

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Optical Fibres

The other day I was playing with optical fibres. The top picture shows two not-polished ends under a microscope. Each edge in the grid is 1mm long. The bottom picture shows that the optical fibres we use can actually transmit light! 🙂

Tomorrow will be the great day: the first time we let water flow through our experiment!

Written by Claus

March 22nd, 2011 at 9:36 pm

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Written by Claus

March 16th, 2011 at 11:11 am

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Written by Claus

March 9th, 2011 at 11:11 am

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If You Think it Might be Homogeneous

This is such a simple experiment, but yet the resulting picture I think is beautiful.

Remember the permeameter experiments from a few weeks ago? We used that same column of sand and injected some dye into it at the bottom. The injection was continuous, and hence a front started to form. You should also remember that we placed industrial sand into the column. That’s the most homogeneous sand imaginable. It has a straight sieve curve. Additionally, just to make sure to stay in as homogenous settings as possible, we tried to pack the sand as homogeneously as we could into the column. And still, this is what we got:

In some zones the tracer advanced more rapidly than in other zones. And zones with substantially different advancements are very close to each other. The diameter of the column is 10 centimeters. This is one of the most classic experiments in solute transport in porous media. And still so beautiful! 😉

Written by Claus

March 7th, 2011 at 9:50 pm

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