Inside the caves there are not only sediments of chemical origin, the speleothems, used by scientists to interpret their age and paleoenvironmental conditions during their formation, but there is also an abundance of so-called clastic sediments. They are those formed by grains or particles from the decomposition of previous rocks, through erosion, transport, and sedimentation processes. In the limestone rocky cliffs between Málaga and Rincón de la Victoria, is very common to find caves, large and small, that contain clastic sediments, of marine and continental origin. In fact, this area constitutes a Site of Geological Interest (“Araña Complex”), inventoried by the political administration (Junta de Andalucía) and the Spanish Geological Survey (IGME), due to its great geomorphological and sedimentological interest. Its represented by a set of marine abrasion platforms, marine sediments and continental sediments related to Pleistocene transgressions and regressions, and underground karstic networks that also contain important sedimentary deposits of great geological interest.

In Cueva de las Estegamitas, clastic sediments are very abundant, of different types, textures and colours, origins and, possibly, age. Its study is essential to know the geological evolution in depth. Some are reduced to their minimum expression, enclosed in small openings, which can be seen in the walls, as testimonies of initial moments of the speleological evolution. Others are currently well exposed on the floor of some galleries, well stratified, showing ancient processes of water circulation. Other more recent ones, present remains of microfossils and charcoal, of great interest for archaeological and paleontological studies. Finally, there are some, related to geochemical processes of alteration of certain minerals that are present in the limestone rock, especially pyrolusite (a manganese oxide that grows in the form of beautiful dendritic morphologies that resemble plant structures), which generates abundant deposits of black colour distributed throughout various sectors of the cave, which contrast with the white of the limestone rock and the speleothems.