color diagram by Alexandre Brongniart showing geologic strata
Date: 1829
Inventory Number: 1998-1-1442
Classification: Diagram
Subject:
Maker: Alexandre Brongniart (1770 - 1847)
Cultural Region:
Place of Origin:
Dimensions:
0.5 x 66.4 x 52.5 cm (3/16 x 26 1/8 x 20 11/16 in.)
in container: 0.5 x 92 x 61.5 cm (3/16 x 36 1/4 x 24 3/16 in.)
Material:
DescriptionThis is a theoretical map of stratigraphic time zones throughout Europe designed by the Parisian ceramist, natural history professor, and geologist Alexandre Brongniart in 1829. It is from his last major geological work entitled “Tableau des terrains qui composent l'ecorce du globe," a perceptive but uninfluential text about the ordered classificatory system of rocks, known as stratigraphy today. Stratigraphy was an area of research that preoccupied many 18th and 19th-century geologists, such as Georges Cuvier and William Smith, who were interested in the distribution of various rock divisions based on the similarity of fossils and identifying layers of time based on them. Comparing rock and fossil types and associating them with different time periods occurred on a global scale, which led to an international geological time scale, dividing the Earth's history into bands, with the most recent history at the top and the most ancient at the bottom.
Similar to many other maps at the time, the map legend indicates various colored and textural codes to identify each stratigraphic layer and indicate its physical properties. Brongniart's maps usually betrayed an interest in depicting horizontal rather than vertically arranged strata, as well as the external characteristics of mineral and fossil contents, shapes, colors, textures of strata, which is similar to the practice of lithology today. He arranged this information in cross-colored sections, called "coupes." These "coupes" were often hand painted with watercolors to show depth and shadows. Color lithography was invented much later in 1837, and replaced hand coloring on geological maps after this date.
Brongniart's maps diverged from contemporary ideas because they attempted to distinguish "time units from rock units,' according to Martin Rudwick. Rudwick states that "his first and main division of time was between a période jovienne (Recent) and a période saturnienne (all earlier time); the sedimentary rocks of the latter were divided into Terrains clysmiens (“diluvial” or glacial deposits) and Terrains izemiens (all other sediments). This implied a distinction between past and present and a unique role for the most recent “revolution” (the glacial period), which were far more questionable than he seemed to realize. On the other hand, he made a clear distinction between the Terrains stratifiés ou Neptuniens, which invariably occurred in the same order, and the Terrains massifs ou Typhoniens (broadly, igneous rocks), which might be intercalated at any point in the series." Although Brongniart made the distinction between rock and time units in order to prevent confusion, it ultimately became more confusing than combining the two types, so his work failed to gain recognition even though it was rather perceptive for its time.
Similar to many other maps at the time, the map legend indicates various colored and textural codes to identify each stratigraphic layer and indicate its physical properties. Brongniart's maps usually betrayed an interest in depicting horizontal rather than vertically arranged strata, as well as the external characteristics of mineral and fossil contents, shapes, colors, textures of strata, which is similar to the practice of lithology today. He arranged this information in cross-colored sections, called "coupes." These "coupes" were often hand painted with watercolors to show depth and shadows. Color lithography was invented much later in 1837, and replaced hand coloring on geological maps after this date.
Brongniart's maps diverged from contemporary ideas because they attempted to distinguish "time units from rock units,' according to Martin Rudwick. Rudwick states that "his first and main division of time was between a période jovienne (Recent) and a période saturnienne (all earlier time); the sedimentary rocks of the latter were divided into Terrains clysmiens (“diluvial” or glacial deposits) and Terrains izemiens (all other sediments). This implied a distinction between past and present and a unique role for the most recent “revolution” (the glacial period), which were far more questionable than he seemed to realize. On the other hand, he made a clear distinction between the Terrains stratifiés ou Neptuniens, which invariably occurred in the same order, and the Terrains massifs ou Typhoniens (broadly, igneous rocks), which might be intercalated at any point in the series." Although Brongniart made the distinction between rock and time units in order to prevent confusion, it ultimately became more confusing than combining the two types, so his work failed to gain recognition even though it was rather perceptive for its time.
Signedat the top of the chart: par Mr Alexandre BRONGNIART, Professeur de Mineralogie au Museum d'Histoire-Naturelle de Paris
Inscribedat the top of the chart: TABLEAU THEORIQUE de la SUCCESSION la plus generale en EUROPE, des TERRAINS et ROCHES qui composent L'ECORCE de la TERRE./ ou EXPOSITION GRAPHIQUE du Tableau des Terrains, Publie en 1829 par Mr. Alexandre BRONGNIART, Professeur de Mineralogie au Museum d'Histoire-Naturelle de Paris.