Madrid and Andalusia
Written by Erik Sturkell
In November I traveled to Spain to work with impact-colleague Jens Ormö. During the first two weeks we worked in Madrid at his impact laboratory. The last week was spent in the field in southern Spain (Andalusia) studying different types of breccia. During the weekends, Jens organised activities that included historical visits to Roman remains in Spain and geologically interesting sites.
On the 7th of November I left Gothenburg on a flight en route to Madrid through Munich. Traveling nowadays is much more complicated than before and this is Europe! To get the boarding card I needed an entry form to Spain (SpTH). To get this form you needed to include the seat number and to get a seat number you needed to check-in. Thankfully I could do a “check-in” without getting the boarding card. Now I could get the entry form from Spain and upload to the airline (LH) getting my boarding card. The flight was nice, and I got to Madrid and outside Jens picked me up. He had found a nice hotel in the suburb Coslada about 10 minutes from Jens’s work, at Centro de Astrobiología CSIC INTA in Madrid. Jens picked me up every day at 9AM and we worked in the impact laboratory most of the time. Jens has created a fantastic facility for impact experiments. It took almost two working days to make one experiment during the first week, but much quicker the second week.
During the two weeks’ visit at Centro de Astrobiología CSIC (CAB) Jens and I did six experiments of which four was a great success. Jens has a canon (Figure 1) propelled by compressed N2 gas up to 300 bars. To make crater experiments different types of geometries are applied; full space, the explosion takes place in the target; half space, the explosion makes place in the surface and quarter space the explosion takes place next to a glass wall, so the profile of the crater appears (figure 2). We did quarter space experiments with Jens’s canon (Figure 1).
We used both a 20 mm Delrin plastic ball and a cluster of 311 3 mm Delrin plastic balls. The two projectiles should have the same weight. One of the challenges was to glue the 311 small balls together.
The “rubble plie” experiments worked quite well and the next step was to find the right glue that hold together the cluster of 311 Delrin plastic balls a little longer. The “rubble plie” shot gave a wider and shallower crater compared with the single larger (20 mm) projectile. The experiments worked well and during the two weeks Jens and I got an efficient routine. Also, we got help by Jens college Isabella in the experiments.
First, we did a vertical shot with a cluster projectile, first all lose and second lightly glued together. This was done in the first week. The second week we tilted the canon and made oblique shots (Figure 1). First a solid 20 mm ball. The second shot turn out perfect the crater formed next to the window. Finally, we did oblique shots with cluster projectiles. On Friday afternoon we did the finale shot, during the time we made six shots. Now we have a lot of material for our ongoing and future research.
On the weekend 13–14th November I was invited to Maria (Rosa) and Jens’s summer house in San Martin de Valdeiglesias. This is a town of about 5000 inhabitants located 1–1½ hour from Madrid. They have a fantastic house (Figure 3). The geology of the area is characterized by Variscan granite forming a landscape of erosional remains of a deep weathered bedrock (Figure 4). Jens took me out on a sightseen trip both days. On Saturday we started ay the bulls of Guisando (Figure 5), that is sculpted in granite. At this place an important treaty was signed 1468 that lay the foundation for the Kingdom of Spain with Ferdinand and Isabella. Next, we drove to the old Roman road and stopped at one of the bridges (Figure 6). After some more ruins we went home and started the barbeque of an Iberian pig by slow cooking. On Sunday Jens took me to the hills above the town with deep weathered granite and amazing tor formations (Figure 4). In the evening we returned to Madrid.
On Saturday the 20th Jens, Maria (Rosa) and their daughter Anna took me to Segovia. On the way out we took the scenic route over the mountain over the pass at Puerto de Navacerrada (a ski resort) at 1858 meters altitude. On the way up the mountain, we stopped at the “La Fuente de los Geólogos” the geologist spring (Figure 7) erected 1932. The first thing we did in Segovia was to have lunch. I ate a specialty for the region the “Segovia Suckling Pig, or Cochinillo de Segovia”. After the lunch we hit the town, first passing under the aqueduct (Figure 8) reaching a height of 28.5 meter. The aqueduct was constructed at the end of the first century AD. Following the aqueduct into the old town and we walked to the castle (Alcázar de Segovia) that date back to the 11th-century. The castle went through a major makeover in the 16th-century to the “fairytale” style (Figure 9). This castle was one of the role models for Ludwig II building in Neuschwanstein. From the castle Jens pointed out the church where he and Maria (Rosa) got married in 2005 (Figure 10). The Cruz de Segovia church is built and still maintained by the order of Hospitals of St. John later the Maltase knights.
After a well-deserved rest from the Segovia expedition. Jens picked me up after lunch and we drove for 20 minutes to the northeast, to the town Alcala. In the suburbs of this town is a partly built on the roman town Complutum. First, we visit the excavated part of the town, which includes the forum. Next stop was a school budling named “casa Hippolytus”. The name refers to the person that made the mosaic in the floor (Figure 11).
The third week of my Spanish travel, Jens took me to Andalusia in the south. We meet up with two of his collogues who showed us plentiful of different breccias (Figure 12). The abundant breccia within a restricted area gives the notion of a possible impact structure. As breccia can be formed in different geological settings nothing is certain, but let’s be optimistic.
Jens – thank you for a fantastic trip both professionally and for the social activities!