Geological profile

North-south section through Monte San Giorgio

A geological profile is a graphic cross-section through the (mostly uppermost) areas of the earth's crust , in which the spatial arrangement of rock bodies , faults and other geological structures in the subsurface is shown. A geological profile is often a supplement to a geological map or is represented in a model. The scale can vary between a few 100 meters and several 100 kilometers. In contrast to pure height profiles , geological profiles are not shown exaggerated so that thicknesses and, if applicable, angles of fall are not unnecessarily distorted. To create a geological profile, both directly obtained data from rock outcrops (on the earth's surface and from drill cores ) and indirect data from geophysical measurements ( borehole geophysics , seismic investigations) are used.

Profile section through the north-west German basin from west-south-west to east-north-east. It contains the layers from the Rotliegend ( lower or middle Perm )

history

A first drawn profile probably comes from Johann Gottlob Lehmann (attempt of a history of the Flöz Mountains in 1756) and is from the southern edge of the Harz near Nordhausen . It shows a section from Grauwacke via Rotliegend and Zechstein to Buntsandstein from Ilfeld to Nordhausen. A little later, Georg Christian Füchsel in Thuringia built on this with the first geological map in Germany in 1762.

Johann Gottlob Lehrmann's profile through the southern Harz in 1756 near Ilfeld and Nordhausen

In England, John Whitehurst made geological profiles in Derbyshire in 1782 and, from 1785, the sculptor White Watson in the form of display panels.

Geological profile of a mountain in Derbyshire by White Watson from 1785

Demarcation

The stratified or columnar profiles that can also be found in geology are not to be confused with geological profile sections. These serve the sometimes very detailed representation of sedimentary strata on a meter scale, as they were encountered in individual daily outcrops or drilled during a drilling. In this context, it is not uncommon for the exposed layer sequences to be referred to as "profiles" , similar to soil profiles. Such profiles are mainly used in stratigraphy and sedimentology .

Individual evidence

1. ↑ Wagenbreth, History of Geology in Germany, Springer 1999, Figure 21, p. 26. The geology of the area can also be found in a block diagram in Wagenbreth, Steiner, Geologische Streifzüge, Leipzig 1990, p. 69