Ardoisières d'Emeschbaach EarthCache

Ardoisières d'Emeschbaach

Individual rocks deposited at the bottom of the sea were transformed into hardrock through compaction, argillaceous muds into schist and sand into sandstone.

The rocks were folded into anticlinal and synclinal arches during the formation of the Ardennes mountain range about 360 million years ago, the schists took on their schistosity in parallel to the development of the axial plains of the folds, and the sandstones were fractured and transformed into quarzite, this rock is more compact since the quartz grains have fused with one another.

The Ardennes rock mass emerged from the sea and was subjected to erosion and with this a new relief was formed during the Mesozoic and Tertiary geological periods.

All the rocks constitute minerals in variable proportions, most important are Quartz, the argillaceous Minerals and the Carbonates. The schists and quarzites of Eisleck are made primarily of Quartz and argillaceous Minerals. The properties of these two minerals make it possible to differentiate them. Quartz fragments are sharp, quartz is hard and easily scratches glass; the argillaceous minerals are soft and like small flakes, they are easily scratchable with a nail or even a fingernail. Slate schists are formed from a stacking of argillaceous mineral flakes and fragments of the rock are always flattened in this way. This characteristic appears less and less as the schist becomes sandier (and less and less scratchable with a nail!). Quartzite fragments are very sharp. Quartz veins again cut through the rock.

Asselborn slate mine in the settlement of Emeschbach was developed in the eighteenth century, but closed due to its unprofitability after 20 years of operation. The quarry was again taken into use from 1818 until 1969. It was then definitively closed and was used as a water reservoir. During its heyday, between 70 and 100 people earned their living there, but just before closing this had dwindled to 12.

At N50° 05.753 E5° 58.487 you can find a lorry with slate.

•  Go to WP1: N50° 05.318 E5° 57.870 and take a picture of yourself or GPS in the open quarry. Add this picture to your log. This quarry shows you the structure of the slate.
   
• Go to WP2: N50° 05.253 E5° 57.234 and there take another picture of yourself or GPS in front of the slate structure. Add this picture to your log.
   
• During your walk from WP1 to WP2 you can see the slate on your right-hand side and you will pass a notice saying ‘BIOTOP Anciennes Ardoisières’. What is the distance from WP1 to the notice:
  A: +/- 300 meters
  B: +/- 500 meters
  C: +/- 700 meters

To log this earthcache you will have to add the requested pictures to your log. Then send us the answer using the profile. Please log and answer in English, German or Dutch.

LOGS WITH AN INCORRECT OR NO PICTURE, OR LOGS FROM PEOPLE WHO E-MAILED INCORRECT ANSWERS TO THE QUESTION, OR LOGS CONTAINING ANSWERS OR HINTS ARE REMOVED IMMEDIATELY!!!

Have fun!