[Ban Nam Mut]
Geology of Thung Salaeng Luang NP
For the next four days, our base camp was the small ranger station Ban
Mung at the western slopes of Thung Salaeng Luang national park, directly
situated at the cliffline of a huge karst tower. The landscape in this
part of the park is characterized by the smooth, rounded relief of upper
and lower Jurassic sandstones. Along the southwestern tip of the park,
outcrop, here the morphology is dominated by steep, rugged karst towers
overlooking the flat outwash plains with their patchwork of fields. As
the sandstone areas are often covered by secondary forest, while the more
rugged and dissected limestone areas are still the habitat of priscine
forests with their denser vegetation and their darker colours, the change
in vegetation is a first indicator of the geological setting. Some
isolated karst towers left over by the backward erosion of the main
plateau are looming over the flat fields, adding to the pittoresque
character of the landscape. However, these relatively pure limestone
hills are an easy target for the local mining industry, thus exploitation
of some towers has left some ugly scars around.
A geological sketch map showing the locations of the caves Tham Dao (1),
Tham Phra Sai Ngam (2), and Tham Phra Wang Daeng (3) is shown next.
The outlines of the three caves surveyed are shown (in black) on the next map, together
with the limestone outcrop (grey) and some rivers (blue) draining the plateau.