Limestone & Calcite in 1!

Here is a limestone rock I picked up whilst walking through the forest above the Bielefeld Tier park in Germany. The fact that it is largely limestone shows that this area when it was submerged in the shallow sea had an abundance of life.

Interesting to note the mineralised calcite on the surface fig 1 This rock differs from what is found further south down Teutoburg ridge which is predominantly Sandstone. The rock formations in this area were uplifted during the Late Cretaceous (~90 Ma) this tectonic movement was an effect of the continents of Africa and Europe colliding, placing horizontal pressure on the European continent. The same Oregonian event created the Alps in southern Germany.

More info can be found here at the Geographical Commission for Westphalia: 

WESTPHALIA IN THE UNDERGROUND: TECTONIC UNITS

fig1

fig2

Paderborn Dom Paleogeology

Rochelle and I were walking through Paderborn on a nice Sunday stroll when I decide to have a closer look at the Sandstone used to build our cathedral when to our surprised we found fossils embedded in the wall!

We quickly started to take some photos of what we assumed were shells of  Brachiopoda fig1 and 

coral's fig 2

If anybody has any better clues then please do post below, I have also posted the location where you can view these yourselves the next time you are in town.

fig 1 (Brachiopod Shell)

fig 1 (Brachipod Shell Closeup)

fig 2 (Coral)

fig 2 (Coral & Shell)

Location of the fossils

Externstein Rock Exposure

Below is a Sandstone exposure which is part of the Externestein rock formation, this particular exposure is ~300m to the west of the main monument, it was formed as part of the regional uplift which happened ~90ma ago. 

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More info at this link (German)

Here is a piece sandstone gathered from the right of the formation. 

Notice the minute stratification at a,b & d and especially where it has broken along the line a.

Also worth noticing is the red colouration in the middle of the rock, this is indicative of a high iron content when the sediment was laid.

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This sandstone bed was in fact a shallow sea floor (Westfalen Bay) prior to it being uplifted, the Externsteine formation was pivoted on an axis, subsequent glaciation & weathering has led to create the distinctive exposures we see today