Avenc del Boix

Entrance of good dimensions (7 x 2.5 m). Through the lower lip one enters a shaft of 6 metres of drop that gives access to a wide illuminated chamber. In the SW corner, between the blocks, one can descend to a small lower cavity. From the signs of erosion observed on the walls of the shaft it seems to be an old sinkhole of the Fondo del Bruc, today totally dismantled and hanging over the slope. Once the lower passage has been passed by desobstruction (2014) one reaches an inclined and elongated chamber (Sala Joan Ramia), from which a series of branches emerge, to the right and left, of very complex route and quite decorated, with an important development of the conduits, and more so considering it is a cavity developed in the upper zone of the Garraf massif where the general tone is of vertical predominance.

Structure (Extracted from Espeleobloc; JM. Victoria)

From a morphostructural point of view the avenc del Boix is a quite interesting and infrequent case in the Garraf massif, although with a preliminary view we can only point out some details, we hope that with a more in-depth analysis they can be defined with precision. At first we see that the development of the successive chambers is conditioned by a dipping structure of about 30/35 degrees that is subdivided by the action of stalagmitic coverings that at the same time hide a previous clastic process. The role of fracturing seems to play a secondary part. Reddish parietal coverings are frequent, indicating a process of generation in warmer climates. In the points still free of this abundant lithogenetic process that characterises the cavity, we find numerous samples of the primitive dissolution-corrosion process, even with some example of ascending flow.