A number of the crests and hollows located at distance about 1000 kilometers to the North from the mountain of Olympe representing an ancient extinct volcano contains certificates of the powerful tectonic tension which arose in the territory of the Acheron Fossae area of a surface of Mars about 3,7-3,9 billion years ago.
On this type imprinted by means of the office of Mars Express of the European Space Agency the western part of the Acheron Fossae area, the isolated site of the ancient area stretching approximately for 800 kilometers in length and 280 kilometers width with an average height about 2 kilometers in relation to the plains surrounding it is provided.
The Acheron Fossae area is a part of network of the cracks stretched extensively from Farsid’s height located approximately in 1000 kilometers to the South from Olympe’s mountain and which is the location of the largest Martian volcanoes. Historically as “swelling” of area of Farsid resulted from accumulation under the surface of fusion of rocks which began to stream through volcanoes subsequently, the surface of the planet in this area became covered by network of small cracks.
This process gave rise to classical geological education like “horst and a graben” which reminds alternation of white and black keys on a piano where “horst” call the raised site of a surface (“a black key”), and “graben” – the site of a surface located lower than two “horsts” (“a white key in analogy to piano keys”), adjacent to it. On the provided photo the long crest stretched in the left lower part of a picture actually represents a graben which after the forming during the subsequent eras was filled with the breeds moving along it, perhaps with glaciers.