Abraham Gottlob Werner

Abraham Gottlob Werner (September 25th 1749 or 1750 – June 30th 1817), was a German Géologue which establishes a theory discussed on the Stratification of the formation Earth and created the obsolete word Neptunisme from now on.

Life

It was born with Wehrau, a town of Prussian Silesia , in the south-east of Germany. Werner made his education with Freiberg and Leipzig, where he studied the right and mining geology, and was then named inspector and professor of the mines and Minéralogie to small but influential the Université of the mines and of technology of Freiberg in 1775. During his career, Werner published very little, but its fame of professor was spread through Europe, attracting students who became his virtual disciples, and propagated its interpretations through their countries of origin, as Robert Jameson who became professor with Edinburgh and Andrés Manuel del Río which discovered the Vanadium. Lecturer with the Socratique style, Werner of the Geology in its students, who offered an enthusiastic and attentive audience. Unfortunately, Werner was tormented all his life by a fragile health, and passed a quiet existence in the immediate surroundings of Freiberg. Avid mineral collector in its youth, it gave up the work of ground thereafter. There does not exist any proof that it ever travelled beyond Saxony of all its life of adult. He died in Dresden of internal complications which one says that they had been caused by his consternation vis-a-vis misfortunes which occurred in Saxony during the Napoleonean wars .

Theory of Werner

Werner applied the superposition in a classification similar to that of Johann Gottlob Lehmann. He believed that the Earth could be divided into five formations:

Primitive Series (Urgebirge) - igneous Rock intrusive and métasédiments of high ranking considered as being first precipitates resulting from the ocean before the emergence of the grounds.
Series of Transition (Ubergangsgebirge) - more hardened, Calcareous S, Dyke S, Sill S, and thick sequences of Grauwacke S which would have been the first deposits of the ocean. Those constituting of the formations " universelles" extending without interruption around the world.
Secondary or Laminated Series (Flotz) - the remainder of the rocks clearly laminated and fossiliferous and certain rocks " pièges" associated. It was thought that they represented the emergence of mountains of under the ocean and were trained by the deposit on their sides of the products resulting from the erosion.
Alluvial Series or Tertiary sectors (Aufgeschwemmte) - little consolidated Sand S, gravel S and Clay S formed during the withdrawal of the continents by the oceans.
Volcanic Series - épanchements younger of Lava S which one can show obvious association with the volcanic chimneys. Werner believed that these rocks reflected the local effects of layers of coal in combustion.

The basic concept of the geology of Werner resides in the belief in an ocean including all, then gradually regressing until its current location while precipitating and virtually depositing all the rocks and minerals of the earth's crust. The highlighting of this initially universal ocean gave birth at the end Neptunisme which applied to the concept and became virtually synonymous with the teaching of Werner, although the concept was born in France with Jean-Etienne Guettard. A universal ocean led directly to the idea of universal formations, which believed Werner could be recognized on the basis of Pétrologie and the laws of the Superposition. It built the term geognosy (knowledge of the Earth) to define a science based on the recognition of the order, the position and the relations between the layers forming the Earth. Werner believed that the geognosy represented facts and not the theory. They resisted the speculation, and finally the geognosy and Neptunisme of Werner led to a dogma, then ceasing contributing to a greater comprehension of the Histoire of the Earth.

Criticisms of the Theory

One of the principal points on which Neptunisme concentrated and caused a quasi immediate controversy was the origin of the Basalte S. basalts, in particular in the form of Sill S, differentiated flows of lava of surface, and both were not recognized like the same type of rocks by Werner and his students at that time. Lava and volcanos obviously of igneous origin were treated like phenomena very recent and not connected to the universal ocean which formed the layers constituting the ground. Werner believed that the volcanos occurred only near the coal seams. Basalts and Wacke S recovering them, burning and melting, produced basalts and lava at typically low altitudes. The presence of basalts with more high-altitude were a proof, for Werner, who they were chemical precipitates of the ocean.

One second controversy surrounding Neptunisme related to the volumetric problems associated with the universal ocean. How could it give an account of the covering of the whole ground, then of the contraction of the volume of the ocean during emergence of the primitive mountains and transient, then of the formation of the secondary and tertiary deposits? The displacement of a significant volume of water towards the interior of the ground at summer suggested before by Strabo, but was not adopted by Werner because of his association with assumptions. Nevertheless, with its sights on basalts, it believed obviously not that the interior of the ground was molten. Werner seems to have retracted the question mainly. He thought that part of water could be lost in space by the passage of some celestial body. However this interpretation brought the question connected of the explanation of the return of water which reflected the secondary rocks.

Heritage

Werner was certainly the most influential geologist of the first part of the Industrial revolution. These extraordinary aptitudes of lecturer attracted students of all Europe, who turned over then in their countries of origin and applied his lesson and concepts. These applications immediately fomented the debate, particularly on the origin of the basalt, and which one refers commonly as the controversy Neptuniste- Plutoniste. This controversy was the focal point of a great part of the activity in geology of the end of the 18th century and 19th century.

A variety of known Scapolite under the name of wernerite at summer named in its honor.

References

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