Geologia di sottosuolo dell'alta pianura a NE di Milano

ABSTRACT: Bini A., Strini A., Violanti D. & Zuccoli L., Subsurface geology of the NE of Milan High Plain. (IT ISSN 0394-3356, 2004). The geological setting of an High Plain area NE of Milan is carried out by the correlation among superficial data and underground ones. Allo-units and litho-units have been recognised in the field relief. The units are principally composed of fluvial, glacial and glaciofluvial sediments and they have an age comprised between the lower Pleistocene and the present time. In order to carry out the underground model, cuttings of water wells have been analised. The main characteristics used in cutting descripitons are: sedimentology, petrography and fossils contents. Moreover, a great number of drilling logs have been considered. The correlation is carried out using rectilinear sections; these sections are oriented in various directions, so that it is possible to determine a three dimensional model of the underground structures. Drills distant no more than 300 m from the sections have been projected on them. The geological reconstruction is based on the determination and the reconstruction of buried surfaces and geological bodies. These surfaces and bodies are recognised by marker or lithological descriptions that are calibrated by superficial data and cutting analysis. In this work three buried units have been recognised. They are: Allogruppo di Vimercate, Allogruppo di Ronco Briantino and Ceppo di Lomagna. The underground model is useful to understand the geological evolution of the area. It is also useful to understand the superficial geological setting in areas in which outcrops are too distant to make a certain model. Finally, a paleogeographic evolution model of the area is proposed.