Timetable of Petrology: The Years 1800-1899

Date Scientist Contribution
1801
Haüy
Traité de minéralogie; classification of rocks on texture. Laid groundwork of modern crystallography.
1802
Playfair
Popular interpretation of Hutton's ideas.

de Montlosier
Recognition of the relationship of basaltic peaks to lava plateaus of the Auvergne.
1804
Watt
Radial crystallization of basalts.

Thomson, G.
First described structure in meteorites named the Widmanstätten pattern by Schreibers (1820). Discounted "celestial origin."
1805
Hall
Fused rocks reproducing texture of natural rock.
1807

First geological society founded: Geological Society of London.
1808
von Widmanstätten
Microscopical study of meteoritic iron in polished section. Structure called Widmanstätten pattern by Schreibers (l820). See Thomson (1804).
1810
von Buch
Defined gabbro (feldspars were saussuritized).

von Buch
First geologic map of Germany.

Humboldt
Volcanoes aligned along fissures. Earthquakes related to volcanism.
1811
Pinkerton
"Petralogy, a treatise on rocks (1200p)"

Haüy
Mineralogical classification of rocks (In letter to von Leonhard).
1812
Hall
Experiments on calcite stability under pressure.

Cuvier
Catastrophic concept of earth changes both physical and biological.
1813
Brongniart
Mineralogical classification of rocks. (Makes no reference to Haüy, 1811)

Berzelius
First record of polished section study of opaque sulfide minerals (letter to publisher).
1814
Berzelius
Mineral classification based on electro- chemical theory and chemical proportions.
1815
Cordier
Analyzed separate minerals from basalt.

Smith
First geologic map of England.
18l6
Hausmann
Compared magmas with metallurgical slags.
1818
Webster
First analysis of an American rock.

von Buch
Settling of feldspar in obsidian by gravity.
1819
Breislak
Aqueous inclusions in igneous minerals are evidence of water present during crystallization.

Mitscherlich
Isomorphism.

Boué
Metamorphism.
1821
Maccullock
Classification of rock formations.

Seebeck
Discovered thermoelectric effect in thermocouples.
1822
Haüy
Traite de mineralogie. Defined the rock eclogite. (See Fermor, 1913).
1823
von Leonhardt
Characteristik der Felsarten. First consistent classification of rocks.

Brewster
Disruption of topaz on heating due to expansion of fluid inclusions.
1825
von Buch
Centers and bands of volcanic action. Concept of a caldera. Reported experimental demonstration by de Drée of the settling of feldspar in a melt held in a crucible.

Scrope
Volcanic rocks erupted from crystalline rocks fluidized by water. Explains basalt and trachyte by differentiation from granitic parent. Expansive force of gases in lavas.
1826
Naumann
Defined metasomatism.

Perkins
First construction of a free-piston pressure guage.
1827
Brongniart
First to distinguish minerals from rocks. Structure vs. texture. Mineralogical classification. Introduces distinction based on origin.

Cordier
Measured thermal gradient at earth's surface.
1828
Nicol
Thin sections of fossil wood.
1830
Lyell
Estimated age of earth on basis of time for change of species at 240 My. Revolutionary treatise rejecting neptunism.
1832
von Buch
Edited geologic map of Germany. (See 1810).

von Leonhardt
Basalt is volcanic with contact phenomena.
1833
Lyell
Defined metamorphic (see Boué, 1819). Promoted the principle of uniformitarianism.
1834
Talbot
Used Nicol prism in testing minerals in polarized light.

Clapeyron
Relationship for calculating the change of melting temperature with pressure.

Fournet
Associated ore deposits with igneous intrusions.
1837
Fuchs
Minerals in granite not crystallized in order of fusibility. Granite formed by consolidation of amorphous magma saturated with water.
1838
Schönbein
First used word "geochemistry" to describe study of chemical and physical properties of rock formations.

Keilhau
Granitification: Transformation of pre- existing rocks into granite and syenite.

Gressly
Defined facies to designate lithologic and paleontologic characteristics of a definite sedimentary stratigraphic unit.

Gauss
Developed general theory of magnetism for the earth.
1839
Ehrenberg
Microscopic study of chalks and limestones.
1841
Abich
Rock classification based on feldspars. Related to degree of saturation with silica (See Loewinson-Lessing, 1890).

Scheerer
Water in magmas increases fluidity and lowers temperature of consolidation.

Daubrée
Emphasized importance of fluorine in ore deposits. Ores deposited from vapors ascending to surface through fissures.

Gay-Lussac
First suggestion of the law of successive reactions. (See Oswald, 1893).
1842
Hopkins
Deduced from planetary motions that earth's crust was at least 800-1000 miles thick and might be solid to the center, except for small vesicular spaces filled with magma. Source of magma: residual lakes.
1843
Boué
Distribution of chemical elements in crust.

Phillips
First to interpret slaty cleavage as an effect of mechanical strain.
1844
Darwin
Floating of porphyritic crystals gives rise to trachyte first and basalt second. Gravity settling. Squeezing and leaching out of magma. Dike formation.

Fournet
Theory of "surfusion": Fusion point lowering.
1845
Schafhäutl
Quartz grown in superheated water.

Dana
Minerals in rocks dependent on temperature, pressure and cooling rate.

Durocher
Discussion of the origin of granitic rocks.
1847
Bischof
Initiated summary of chemical transformation of minerals and rocks: Four volumes on geochemistry.

Beaumont
Distribution of chemical elements in crust (see Boué, 1843). Divided rocks into acid and basic classes.

Durocher
Used the term "magma" in the modern petrological sense of a partially or completely molten rock.

Sedgwick
Metamorphism of sedimentary rocks. Slaty cleavage.

Bunsen
First analysis of a volcanic gas from a fumerole. Dominant constituent is water.
1848
Thomson
Definition of temperature scale independent of properties of materials.

Delesse
Originator of geometric analysis by areal measurement.
1849
Breithaupt
Paragenesis of minerals.

Dana
Magmas all liquid first; slow cooling; heat and pressure determine rock formation. Eruptions result from inflation of gases. Extinction age of Hawaiian volcanoes decreases regularly from the northwest.

Naumann
First use of "petrography" in sense of petrology. Used "petrogeny" to describe rock genesis and defined eruptive rocks.

Whitley
First description of pillow lavas.
1850
Boisse
Composition of meteorites relevant to bulk composition of the earth.
1851
Bunsen
Magma types: two extremes in separate reservoirs. Mixed "normal pyroxenite" with "normal trachyte" to get intermediates. Magmas are solutions: Same principles that apply to behavior of salts in water.

de Sénarmont
Introduction of hydrothermal synthesis. Mineral synthesis with water in a glass tube within a sealed steel tube.

Sorby
First description of microscopical structure of rocks in thin section. (See preparation of thin sections by Nicol, 1828).
1852
Oschatz
Exhibited 50 microscopic slides of mineral sections.
1853
Sartorius von Waltershausen
Layered shells; siliceous upper layer Feldspathic and siliceous rocks are oldest. Gradual cooling gives rise to more basic rocks. Continuum of magmas. Gives geocentric pressure of earth as 2.49 million atmospheres.
1854
Ehrenberg
"Mikrogeologie."

Maury
Bathymetric revelation of the mid- Atlantic ridge.

Whitney
Downward enrichment of ore deposits by meteoric waters.

Hunt
Plagioclase defined as a solid solution.
1855
von Cotta
Rocks as mineral aggregates: one grading into the other. Genetic classification.

von Cotta
First major synthesis of theories of ore deposition.

Kjerulf
Emplacement by assimilation.

Lyell
Age vs. composition (siliceous always oldest). Denser magmas emitted last.

Fick
Diffusion law.
1856
Ludwig
Discovered principle attributed later to Soret.

Highley
First record of upright polarizing microscope.

Durocher
Injection theory for the formation of granite.
1857
Durocher
Two layers of magma, gravity separated. Small amount of intermediates. Idea of liquation. Claims that he, not Bunsen (1851), originated two-magma idea. "Hybrid" rocks from magma mixing. Notes similarity of magmas and alloys.

Jukes
Objects to magma zoning because of alternating layers. Single parent. Relates composition to location. Refractory material at greater depths, squeeze out more fusible portions.

Delesse
Contact metamorphism: alteration of rocks in proximity of igneous rock.

Daubreé
Used glass-sealed tube with water to grow quartz.

Senft
Applied chemical factors to rock classification.

Coquand
Divided rocks into sedimentary, igneous and metamorphic.
1858
von Cotta
Parental universal basic magma. Continuous basaltic layer below acid crust. Variations due to assimilation of siliceous crust.

Sorby
Microscopic description of rocks with water vesicles in quartz.

Oschatz
Presumed to have invented thin- section technique earlier. (See 1852)

Snider
Earth rifted, continents pushed apart, and Atlantic ocean formed.
1859
Green
Observed formation of pillows forming in lava from Mauna Loa, Hawaii, entering the sea. (Publ. 1875).

Phillips
Estimated age of the earth on basis of rate of sedimentation at 96M years.
1861
Bunsen
Magma described as a solution in a letter to Streng. Proportions of constituents determines order of crystallization.

Roth
Published table of rock analyses to date. Chemical classification of rocks based on feldspar and quartz.

Scheerer
Refuted igneous origin of granite on basis of quartz melting argument.
1862
Daubrée
Converted volcanic glass to trachyte in super- heated water.

Jukes
Common origin of volcanic rocks; minerals separated by different P, T conditions and "take up of ingredients."

Scrope
Second edition of "Volcanoes." Gravity separation; squeezing out of more fusible minerals.

Thoulet
Prepared solution for heavy mineral separation.

Thomson, J.
Compressive stress increases solubility of a crystal.

Thomson, W.
Calculated elapsed time since earth cooled from the temperature of solidification (3710deg. C.) as 20-400 million years. (Publ. 1863).

Dana
Originator of the hypothesis of a cooling and contracting earth.
1863
Bischof
"Chemical Geology"; Unable to reduce rock to simple chemical formula.

Thomson, W.
Columnar basalt due to contraction on cooling.

Zirkel
Established systematic microscopic study of rocks.

De Serres
Expressed average composition of the earth's crust in terms of minerals.

Mühry
First record of the term "geophysics."
1864
Tschermak
Concept of solid solutions (See Hunt, 1854).

Kelvin
Age of earth calculated on basis of secular cooling.
1866
Fouqué
Mechanism of volcanoes and petrography of lavas of Santorini.

Ramsay
Granite is metamorphic rock resulting from heat and alkaline waters.

Zirkel
First edition of "Lehrbuch der Petrographie."
1867
Vogelsang
Processes of magma consolidation. Described CO2 inclusions.

Croll
Estimated age of the earth on basis of rate of sediment accumulation at 72M years. (Publ. 1868).

Forbes
Chemical geology. (See Roth, 1883).

Guldberg and Waage
Law of mass action.
1868
Richthofen
Succession of magmas, earliest was most siliceous. Crystallization due to pressure release.
1869
Amagat
Initiated experiments on gases and liquids at high pressures and temperatures. Designed new packing scheme. Observed departures from Boyle's law.
1870
Tschermak
Differentiated hornblende, augite, and biotite microscopically.

Zirkel
Classic study of basalts; classified by feldspar, nepheline and leucite.
1872
Mallett
Mechanical production of local lakes of fusion.

Vogelsang
First hint of petrographic provinces.
1873
Wright
First microscopic investigation of rocks in U.S.

Zirkel
Textbook on microscopic study of rocks.

Rosenbusch
Textbook on microscopic study of rocks.
1874
Cohen
Described volcanic pipe of diamond- bearing tuff (letter dated 20 Sept l872).

Michel-Levy
Described vermicular intergrowths of quartz and plagioclase. (See Sederholm, 1899).
1875
von Lasaulx
Morphological classification of rocks.

Mallet
Columnar structure of basalt.

Des Cloizeaux
Optical determination of composition of plagioclase.

Green
Earth contains a molten substratum with a thin solid crust. (Cf. Daly, 1944)
1876
Zirkel
Microscopic study of King's 40th Parallel rocks.

Gibbs
Phase rule published.

Hawes
First memoir in U.S. on petrography of rocks.

Hall, M.
First description of oceanic basalt.

Reyer
First variational analysis to delimit types of igneous rocks.
1877
Gilbert
Laccoliths of Henry Mountains.

Reyer
Employed diagram to represent relative quantities of rock constituents.
1878
Dana
Rocks are mixtures of minerals like mud. Related texture and occurrence. Average magma erupted before density separation.

King
Localized magmas. Pressure release for fusion. Density controlled. Acid first, pyroxene magma later. Specific-gravity separation of crystals in magma.
1879
Daubrée
"Experimental Geologie"

Fouqué and Michel-Lévy
"Minéralogie micrographique des roches éruptives françaises."

King
U.S. Geological Survey organized.

Irving
First systematic instruction of microscopic petrography in the U. S. (Univ. Wisc. Catalog for 1879-80)

Reade
Estimated age of earth on basis of rate of chemical denudation at 600M years.

Kjerulf
Assimilation theory (See 1855).
1880
Lagorio
Glassy groundmass was solvent for magmatic oxides.

Dutton
Magma generated by local increase in heat, pressure release, or lowering of melting point by water absorption.

Newberry
Relates hot springs to filling of veins. Chemical precipitates from ascending hot water and steam.

Favre
Experimental deformation by compression.
1881
Soret
Stated thermodiffusion concept. (See Ludwig, l856).

Poynting
Deduced relationship for melting point depression by pressure acting only on solid. (See Thomson, J., 1862; Riecke, 1895).

Beckenkamp
Measured dihedral angles of anorthite up to 200deg. C. and calculated coefficient of thermal expansion.

Friedel and Sarasin
Lined pressure vessels with Cu or Pt for hydrothermal experiments.

Michel-Levy
Feldspathization by "imbibition."
1882
Fouqué and Michel-Lévy
Synthesis of rocks and minerals with out superheated water. Demonstrated "isochemical" transformation of mineral assemblages.

Becker
Theory of lateral secretion for generation of ore deposits.

Brögger
Petrography of Kristiania rocks.

Rosenbusch
Proposed empirical rules describing the order of crystallization of minerals in an igneous rock.
1883
Clarke
Established laboratory for chemical analysis of rocks in U. S. Geological Survey.

Roth
Textbook on chemical geology.

Lemberg
Experimental formation of silicates in a copper "digester." Studied absorption of water in natural glasses.
1884
Guthrie
Defined eutectic and applied to the crystallization of granite.

Vogt
Studied slags: igneous rocks at eutectics. Pioneer in application of physical chemistry to silicate magmas.

Van't Hoff
Phase incompatibility.

Le Chatelier
Theorem: Changes outside a system followed by reverse changes within a system.

Lossen
Distinguishes differences in mineral compositions between contact and regional metamorphism.

Koto
First microscopic study of Japanese rocks.

Phillips
Continuum between magmatic and meteoric solutions.
1885
Suess
Atlantic and Pacific rock types. Defines batholith and concept of forcable emplacement.

Lapworth
Concept of mylonization: Extreme granulation and shearing of rocks through dynamic metamorphism. (Publ. 1886).

Liveing
Step rule of chemical reaction. (See Ostwald, l893).

DeKroutschoff
Spectral analysis of minerals.
1886
Judd
Petrographic provinces.

Hunt
Metasomatic hypothesis for the origin of crystalline rocks.

Emmons
Ore deposits due to replacement of country rock by descending solutions leaching metals from country rocks.

Doelter
Synthesis of rocks and minerals.

Seger
Used series of cones with fixed temperature of fusion to estimate relative high temperatures in a kiln. (trans. and publ. by Hecht and Cramer, 1902).
1887
Lagorio
Crystallized glassy groundmass thereby illuminating the processes of crystallization in a magma. Emphasized com- position: temperature and pressure are subordinate.

Stecher
Mineral composition of rock at time of intrusion represented by rapidly cooled margins.

Le Chatelier
Used Pt-Rh thermocouple. (See Barus, 1889).

Lewis
Volcanic breccia of porphyritic mica- bearing peridotite described as kimberlite.

Lawson
Refusion of pre-Keewatin rocks to form Laurentian granites.

Gouy and Chaperon
Sedimentation in a solution (e.g., magma) with accumulation of particles at the bottom results in local increase in osmotic pressure and the tendency of particles to diffuse upward.
1888
Teall
British petrography with special reference to igneous rocks. Interpreted pegmatites as eutectic.

Bertrand
Igneous rock distribution in Europe. Correlated orogenesis with eruptives.

Kozerovsky
Demonstrated experimentally the isomorphism of the plagioclases. Generated basalt by fusion of mineral constituents.
1889
Morozewicz
Experimental formation of minerals in magma.

Iddings
"Crystallization of igneous rocks." Emphasized derivation of magmas from a common intermediate magma. Defined phenocrysts.

Barus
Published earlier studies on thermocouples. Preferred Pt-Ir. (See Le Chatelier, l887).

Rosenbusch
Described differentiation of original uniform magma. Refutes liquation idea of Durocher; prefers concept of "spaltung" (separation into chemically different magmas). (See Daly, 1925).

Stefan
Theory for solving the cooling of a lava flow or a lava lake.

Clarke
Relative abundance of the chemical elements in the earth's crust. Searched for but did not find periodicity of the elements.

Rebeur-Paschwitz
First record of an earthquake (Tokyo, 18 April 1889) with a horizontal pendulum.
1890
Dana
Mechanics of eruption of Hawaiian volcanoes.

Brögger
Common parentage of alkaline rocks of southern Norway. Not from universal fluid, but from successive eruptions out of a separate reservoir.

Iddings
First use of the variation diagram. Often referred to as a Harker diagram. (See 1909).

Loewinson-Lessing
Chemical classification of eruptive rocks. Diagramatic plots of constituents. Concept of silica saturation (See Shand 1913).
1891
Vogt
Molecular diffusion without separation of minerals.

Sederholm
Used term "rapakivi texture"to describe ovoids of perthitic microcline mantled with oligoclase in some granites. (See Hjärne, 1694).

Hatch
Textbook of igneous petrology.

Nernst
Distribution law: Constant ratio between concentrations of a molecular species in any two phases at constant temperature.

Roberts-Austin and Rücker
Measured specific heat of basalt in drop calorimeter (See Barus, 1893).
1892
Iddings
First Professor of Petrology so named in world (University of Chicago).

Iddings
Recognition of isochemical rocks from a magma solidifying under variety of physical conditions producing different mineral assemblages (Yellowstone Park).

Iddings
Defined two broad groups of igneous rocks: Alkali and sub-alkali. (See Harker, 1896).

Dakyns and Teall
Continuous process from one magma; basic to siliceous, transitions rare.

Clarke
Calculated average composition of common igneous rocks.

Kirk
Plastic deformation of marble at high confining pressures.

Reyer
Experimental demonstration with plaster of the mechanics of intrusion, eruption, and flow of magma.

Dutton
Concept of isostasy: gravitational equilibrium of regions of different mass and density.
1893
Barus
Measured specific heat of diabase. Calculated change of melting point with pressure. Determined volume change on melting.

King
Estimated change of pressure with depth in the earth, reaching 3.02 million atmospheres at the center, from Laplace's formula for density distribution with radius.

Zirkel
Second edition of textbook on petrography. Considered most comprehensive.

Bakhuis Roozeboom
Application of Gibbs thermodynamic theory to multicomponent phase equilibria.

van Rijn van Alkemade
Theorem regarding the maximum of temperature on a boundary curve crossed by a line connecting the composition of the two solid phases. (Alkemade theorem).

Ostwald
Law of successive reactions. (See also Ostwald, 1897, and Gay-Lussac, 1842).

Lepsius
Volume law: Increase in pressure led to formation of minerals of higher specific gravity.

Fedorov
Universal stage for the petrographic microscope.

Lea
Shearing stress increases rate of certain chemical reactions.

Barrow
Introduced concept of progressive regional metamorphism. Used critical index minerals to define metamorphic zones (Barrow's zones). Associated regional metamorphism with magmatic heat. Proposed filtration differentiation, squeezing off of residual liquid.

Teall
Pillow lavas of submarine origin.

Williams, H. S.
First use of the term geochronology to describe geologic time scale.

Geikie
Refers to rocks injected or impregnated with abundance of granite "substance" as "granitised." Granitisation (also granitization). (See Durocher, 1856; Bell, 1906).

Lacroix
Described blocks of gneiss transformed to porous glass by enclosing basalt.

Amagat
Summarized 25 years of work up to 3 Kbar and 200o C. on compressibility of gases and liquids. Describes special packing technique. (See Amagat, 1869).
1894
Lowenherz
First phase diagram for Stassfurt salt deposits.

Lacroix
Nodular inclusions in basalts related to the host rock. (Cf. Heritsch, 1908).

Posepny
Ore deposits from hot waters ascending from depth where solubility of all substances increase with higher temperature and pressure.
1895
Högbom
Alnö carbonatite.

Riecke
Application of the Thomson effect to geological materials: Solubility of a crystal increases under nonhomogeneous pressure (stress). (See Thomson, J., 1862).

Harker
Atlantic and Pacific facies of eruptive rocks.

Dana
Earth solidified from the center outward.
1896
Becquerel
Discovery of radioactivity.

Wiechert
Used geophysical data to support concept of an earth's core made of iron.
1897
Becker
Fractional crystallization. Superheat in magmas unlikely. Estimated kinetic viscosity of flowing lava.

Becker
Considers diffusion as unimportant in rock differentiation.

Geikie
Description of eroded volcanoes of Great Britain. Space and time distributions of rocks.

Teall
Iron-enrichment concept.

Hillebrand
Methods of chemical analysis for silicate rocks.

Goodchild
Age of earth estimated from rate of accumulation of limestone.

Sederholm
Proposed vermicular intergrowths described by Michel Levy as myrmekite. Represent latest stages of consolidation of a magma or ultrametamorphism.
1898
Morozewicz
Synthesis of rocks in clay pots.

Rosiwal
Geometrical method of areal measurement.

Van Hise
Deformation by rock flowage.

Joly
Used platinum strip furnace to determine the melting point of rocks and minerals.

Wiechert
First professorial chair in geophysics (Göttingen University).

Lane
First application of Fourier's (1822) heat conduction equation to the variation of grain size in a dike or sill.
1899
Barus
Absorption of water in hot glass.

Joly
Estimated age of earth on basis of rate of accumulation of Na + K in ocean at 90M years.

Bonney
Discovered diamond in eclogite nodule from kimberlite. Considered eclogite parental rock of diamond.


[Timetable of Petrology Contents] [The beginning through 1799] [Years 1900-1949]