Today was a simple driving day. I started about 8:30 am,
first of all getting down from my lofty mountain perch using a good highway
with endless curves and fantastic views of the deep valleys that surround
Manizales (my only complaint with Colombian highways is that they have narrow
shoulders and no place to stop to take pictures). These valleys is where much
of the famous Colombian coffee comes from, so one sees acres and acres of
well-groomed coffee plantations, interrupted—of all things—by dense copses of
bamboo.
Once I reached the lowlands, it became an easy drive due
south along the valley of the Rio Cauca, which reminded me very much of the San
Joaquin Valley. It is a narrow (~30 km wide) valley with a flat floor, where
agriculture thrives. I didn’t see any significant irrigation works, so I think
they rely on the abundant rainfall for growing vast expanses of corn and sugar
cane. From a geologic point of view, this valley between the magmatic arc and
the forearc fold-and-thrust belt, mirrors the valley of the Rio Magdalena
between the magmatic arc and the back-arc fold-and-thrust belt. On first blush
they look like rifts (i.e., the product of tensional stresses), which would
seem odd in the compressive stress regime of a subduction-related orogenic
belt. These tensional features are one of the supporting arguments in favor of
the theory of gravitational spreading of orogenic belts. In brief, the idea is
that as the magmatic arc adds mass to the axis of the belt the latter grows; as
it rises it becomes gravitationally unstable (like a tall pile of mashed
potatoes) and under the influence of its own weight spreads out (again like a
tall pile of mashed potatoes), becoming wider as it pushes the rocks away from
its axis (hence the presence of the symmetric fold-and-thrust belts).
I enjoyed the ride, and the Sancocho de Gallina I had for lunch, but was ready for a break once
I reached the city of Cali, maybe around 2 pm. Didn’t look like much to be
honest, but I will give it an honest chance. By now I know the basic layout of
Colombian cities, which use a grid of numbered calles at right angles to numbered carreras. I was heading for Calle 9 and Carrera 10, which should
put me near downtown. My signal was the Marriot Cali, two blocks away, which
should be a recognizable tower. Man, the deeper I go into the city the worst it
looks. I am not faint of heart, but looking around I soon realized that I could
not possibly stay in this area, if nothing else because my little car would be
stripped if I left it alone for more than a few minutes on the street. Screw
it, I am going to look for a good hotel and treat me to a good night sleep.
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