Progress on the Basadingen borehole has slowed down a bit as we have reached sands at the base of the upper gravel section. These are difficult to drill. Nevertheless, we now reached 57 m.
Drilling commences on the second Tannwald borehole. The weather is hot, but we have to cope with thunderstorms and the drilling rig has to be abandoned during the storms. Nevertheless drilling continues at a fast pace.
Basadingen: The upper gravel section is cored with a ramming drill hammer and sturdy drill bits. Bits with metal pins are ideal for shattering gravel clasts but wear out rapidly (note the missing pins). This one is now replaced.
Tannwald: At the drill site our drilling team installed the standpipe for the second borehole. The standpipe is now set at a depth of 10 m and flush drilling can commence.
Basadingen: Another successful day: we could keep up the pace and gained another 7 m to a total depth of 28 m at the end of the day.
Basadingen: The drill rig in Basadingen arrived at the site and gets ready for the first core. In addition, the second most important lab instrument is ready: Sebastian Schaller and Marius Büchi enjoy the first core-lab espresso.
The team currently moves the drill rig, so we can post some photos of the drill site. Here, e.g., the 80 mm PVC pipes that were used to complete the first borehole. Above: closed pipes, below: filter pipes for sampling water later on.
It did a good job! View of the 7 1/2 inch rolling drill bit that drilled the first borehole from 42 to 163 metres without a hitch, now stored before drilling on the second borehole starts.
Today we had outreach with the local kindergarden and primary school on-site. We showed the children the drill rig and explained them a few basics on the geology of the Tannwald Basin. The kids were a very interested audience.