Hard not to admire Obelisk, in certain areas explorable but mostly distant.
This mountain is surrounded by a productive landscape, surrounded by ranches and due to its length, it accompanies long distances that gauchos, workers and animals travel day by day. Reminder routes that the Sierras de Magallanes are not accidental and are far from being immemorial.
Its extension is such that sometimes we do not know if we are still admiring the Obelisk or if we are already in the presence of a new mountain range that stands in front of it.
The truth is that its length and verticality make it a dividing wall for these productive landscapes, landscapes of work and tourism. Remaining present with them in a persevering way, sadly coming to suffer the normalization of their presence and therefore of their beauty.
Sedimentary rocks form due to the accumulation of sediments that are transported by wind, rivers, lakes, and seas, which are then cemented and consolidated into solid rocks. The type and size of these sediments, just like the environment in which sediments accumulated, determines what kind of rocks is formed and perdured.
A deep ocean deposits fine particles on its floor, millions of years turn into hundreds of meters of accumulated particles that later become a uniform layer of rock, hundreds of meters thick. If the environment changes, sea retreats or advances, a new layer of rock deposits on top of the previous. To distinguish and identify the different sedimentary rocks allows to visualise the ambient in which they formed, how long the ambient lasted and which new environment replaced it. Was it a riverbed, the floor of a lake, or dunes of a desert? History can be told as a column: rocks belonging to a common environment are grouped in Formations, each is the record of an ambient of the past, its thickness how long it was unaltered.
The region of Ultima Esperanza records over 20 million years of sediment accumulation, during the period between 70 and 90 million years ago.
Formations Punta Barrosa, Cerro Toro, Tres Pasos and Dorotea represent each a specific depositional environment, maintained several million years until giving place to the next. Sites such as Mount Obelisco display part of this history, each layer is an episode, a small part of the story that created the landscape admirable today.