Where on Google Earth #207.

For any new players to Where on (Google) Earth, simply post a comment with latitude and longitude and write something about the (geologic) features in the picture. If you win, you get to host the next one.

Because I think that this WoGE is quite easy, I invoke Schott’s Rule: former winners have to wait until posting for 1 hour for each WoGE they got right.

Posting time is 20 June, 14:00 CEST (12:00 UTC).

Have fun and good luck!

Fold at Riedberg Pass, detail view. Stick measure for scale, length 1 m.

Follow this link or click on the image to find out more…

Ark Theory.

(By Bizarro; found at Pharyngula the other day.)

I’m quite happy that I didn’t yet have to discuss with students the creationst crap the cartoon makes fun of.

It’s interesting (similar to the first survey) that in Germany, geoblogs are limited to the east and north. Is there nobody who likes to write about e.g. the Alps?

So now the picture in its complete context:

Groundwater Map of Bavaria 1:25000, Section 6532 Nürnberg (1970).

The “Woman Holding a Fish” was in fact the spatial presentation of thicknesses and hydraulic conductivities of the upper groundwater storey¹ of this map sheet. The coloured areas and small squares show the structure and conductivity of the single aquifers.

Transmissivity

Colours indicate the transmissivites (thickness times hydraulic conductivity K; in Germany k_f), as is shown in the table in the right margin of the map:

Colour scheme for transmissivities.

Hydraulic conductivity (ranges for k_f at the bottom of the table) is mainly determined by aquifer type (unconsolidated vs. solid rock) and stratigraphy (indicated in the table head). Combined with thickness (in 10m intervals – table rows) you get the transmissivities. Darker colours mean higher transmissivity.

Spatial structure

The relation of the layers to each other is shown by bars and small squares. It is explained on the bottom right of the map:

Explanation of spatial representation.

The middle aquifer (Middle Keuper² – Burgsandstein, Blasensandstein) is represented by the continuous colour fill, with different shades of blue (see above). The Quaternary sediments form the upper aquifer, which is only present in some places (valley fills). This aquifer is shown as horizontal green bars that “float” above the middle aquifer plane. The bottom aquifer consists of the Lehrberg Layers of the Keuper in purple colours, onto which you can see “down” through the cut-out squares, or “windows”. In the west, there is now bottom aquifer (the Lehrberg Layers become clayey and act as an aquiclude), so no windows there. Finally, in a few places you have a perched aquifer on top, indicated by bars with a thick red line below (symbolising the local aquiclude).

Similar spaced-out designs can for example also be found in the (later published) Hydrogeological Map of the GDR 1:50000 (HK50):

Hydrogeological Map of the GDR 1:50000, main map.

1. Is this the correct translation for „Grundwasserstockwerk”, i.e. a group of (vertically stacked) aquifers?
2. Keuper is the Upper (Germanic) Triassic.

The hydraulic processes of groundwater in nature cause great difficulties for calculations. To date, the geologist usually tends to rely on imagination [impression? understanding? concept? How the hell do you translate „Anschauung“?] only, and to disregard calculations completely. The mathematically trained engineer, on the other hand, often lacks the necessary understanding [imagination? etc.] of geologic structure. Especially in this field of groundwater science, progress can only be made by close collaboration of the geologist and the mathematically trained engineer.

W. Koehne (1928): Grundwasserkunde [Groundwater Science]. Schweizerbart, Stuttgart. p. 116–117.

Quite flattering how he denies geologists any mathematical skill. Hopefully this has improved since then. I, however, am a mathematically trained engineer who only needs to be acquainted with the understanding of geologic structure.

Just in time before Christmas, I’d like to present the new snowy/icy WoGE #178:

A snowy place as WoGE for Christmas season.

For any new players to Where on (Google) Earth, simply post a comment with latitude and longitude and write something about the (geologic) features in the picture. However, just “a glacier and the proglacial lake” won’t cut it. You’ll need to explain what’s special about this glacier… If you win, you get to host the next one.

Because I think that this WoGE is rather easy, I invoke Schott’s Rule: former winners have to wait until posting for 1 hour for each WoGE they got right.

Posting time is 22 December, 20:00 CET (19:00 UTC).

Have fun and good luck!

Our department (Environmental Geology) offers such practicals since 2007, but other departments have started earlier. Students of the secondary schools “Max-Steenbeck-Gymnasium” here in Cottbus and Carl-Friedrich-Gauß-Gymnasium¹ in Frankfurt (Oder) attend practicals here as part of the “Forschungs-Bildungs-Kooperation” programme (FBK). Sorry, the schools’ and FBK’s websites are in German only.

Both schools have a special focus on mathematics, natural science and technology, and the students choose a practical course topic according to their elected “Leistungskurse” (intensive courses). In our case, these were either biology or chemistry. Sadly, geography intensive courses² are not part of the FBK programme.

Up to now, we had three groups and topics:

• Physical properties of highly concentrated solutions of various salts (Gauß Gymnasium)
• Water quality of a small ditch flowing through a fen (Steenbeck Gymnasium)
• Release of nutrients from strongly degraded peat soils (Steenbeck Gymnasium)

Highly concentrated salt solutions

This was a project quite close to pure chemistry. The students prepared solutions of NaCl, MgCl₂, CaCl₂, MgSO₄, and a few two-salt mixtures at various, high molalities (mostly in the range of 0.5 to 5 mol/kg) and investigated how density and electrical conductivity differ between the salts and how they change a different temperatures, concentrations and mixing ratios.

They found out that some relationsships are quite linear or at least monotonic, e.g. conductivity versus temperature or density versus concentration, but are not the same (different slope, different intersect) for different salts and concentrations. But they realised that there are also non-linear dependencies, e.g. conductivity versus concentration: at very high concentrations, conductivity decreases again (obstruction of ions).

Everytime, and always too late, I realise I didn’t take enough photos of our work, so you have to be satisfied with one of the resulting diagrams. For the following topics, the situation is a bit better luckily.

Example from Gauß Gymansium students' experiments: Density and electrical conductivity for MgCl₂ solutions of different molalities. “1M” = 1 mol/kg.

Quality of water flowing through a fen

My first group of students from Steenbeck Gymnasium measured discharge of a small ditch flowing through a (slightly degraded) valley fen at its beginning and end. Also, measured pH, conductivity, oxygen, temperature and alkalinity on-site, and collected water samples and analysed them for nitrogen (total, nitrate, ammonia), phosphate, dissolved organic carbon, chloride, boron (as sewage indicator).

Dressed for getting wet…

Sadly, I couldn’t find a decent photo of the discharge measurements.

Vacuum filtration of sampled water in the field.

Again, I made some pictures of the sample preparation, but not of the analysis proper.

Preparation for analysis.

With these data, they could balance the fluxes entering and leaving the system. For example, denitrification within the system can be seen nicely.

Nutrient release from strongly degraded peat

This year’s students took soil samples from another fen site, where the peat ist strongly degraded after long time of drainage and agricultural use. Degradation not only means a loss of soil, but also mineralisation of organic matter, i.e. nutrients like nitrogen and phosphorus which had formerly been bound in large organic molecules are now present in mobile forms like nitrate. These could then be leached out, especially when the water table rises again, and affect downstream surface water (eutrophication).

Borehole in strongly degraded peat. (Brighter material at the tip of the auger is the underlying finesand.)

In a simple laboratory setup, we try to find out what could happen after rewetting. Soil samples are extracted with water under controlled conditions (fixed temperature, fixed soil/water ratio, bottles gently rotated for 24 hours).

Overhead-shaker for the extraction of soil with water.

After that, the students measure physico-chemical parameters (pH, el. conductivity, redox) analyse the eluate for nutrient (nitrogen and phosphorus species).

Measurement of pH, electrical conductivity, temperature and redox potential.

We are still working on the project, so there are no nice results to present right now.

1. Gymnasium is the school that is intended as a preparation for university. Have a look at the Wikipedia article on Germany’s “slightly complicated” school system.
2. And there’s no such thing as a geology intensive course.

However, participitation has been low yet. So if you own a geoscience-oriented blog, take this short survey!

The survey is open until 1st November.

Callan Bentley (NOVA Geoblog) did a first survey last year. This year, Lutz Geißler (GeoBerg, Geonetzwerk.org) and Robert Huber (Stratigraphy.Net Internals) have joined the team.

Callan will present the results at the AGU Fall Meeting in December. I’m curious about what has changed compared to last year’s results.

Here’s my new WoGE picture. I hope to attract some new players (or reactivate the old ones), so I choose something not too difficult.

Where on Google Earth #174. The keyword is “hole”.

For any new players to Where on (Google) Earth, simply post a comment with latitude and longitude (or a description of the location) and write something about what the features in the picture are, or how they have developed. Also you need to explain how the keyword fits in there. If you win, you get to host the next one.

Because I think that this WoGE is rather easy, I invoke Schott’s Rule: former winners have to wait 1 hour for each WoGE they got right.

Posting time is 15:30 CEST (13:30 UTC).

Good luck!

1. Yes, it isn’t dead, it just smells funny.

Where on Google Earth #172. The keyword is “Magnesium”

For any new players to Where on (Google) Earth, simply post a comment with latitude and longitude (or a description of the location) and write something about what the features in the picture are, or how they have developed. Also you need to explain how the keyword fits in there. If you win, you get to host the next one.

Because I think that this WoGE is rather easy, I invoke Schott’s Rule: former winners have to wait 1 hour for each WoGE they got right.

Posting time is 16:45 CEST (14:45 UTC).

Good luck!

Modern art.

A purple woman with violet hair, holding a large fish in front of her body? Offer your explanations and interpretations!