Historical Geology The Geologic History of North America

Flea beetle (Chrysomelidae) egg deposition has been found on three impressions of alder (Alnus parvifolia) leaves collected at a roadcut in Republic, Washington. These fossils were discovered by Wes Wehr (University of Washington, Burke Museum) during investigations of fossil plants from the Republic, Washington, area. These impressions represent a yet to be determined species, belonging to the genus Altica GeofFroy (1762). They represent the first member of this genus to be described from the Eocene of North America. The fossils were found in lacustrine rocks from the lower part of the Klondike Mountain Formation. Figure 1 represents the Republic fossil locality and the distribution of this Formation. A brief description of the geologic history of this region can be found in Wolfe and Wehr (1987). The Klondike Mountain Formation has a radiometric age that ranges from 42.3 ± 2.0 to 50.3 ± 1.7 m.y. (Pearson and Obradovich, 1977).

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A THREE-STEP VIEW FOR THE HISTORY OF GEOLOGY

Earth Sciences History ◽

10.17704/1944-6178-38.2.388 ◽

2019 ◽

Vol 38 (2) ◽

pp. 388-402

Author(s):

ALESSANDRO IANNACE

Keyword(s):

Plate Tectonics ◽

Continuous Process ◽

Second Step ◽

Geologic History ◽

The Third ◽

History Of Geology ◽

History Of ◽

Historical Geology ◽

New Community ◽

Epistemological Basis

ABSTRACT The evolution of geology as an independent science can be envisaged as a relatively continuous process yet marked by three fundamental steps. These represented singularities which established significant advances in the epistemological and heuristic power of the discipline. This interpretation of history has to be strictly based on an evaluation of the epistemological basis of geology according to modern scholarship. The recognition of these ‘golden spikes’, albeit artificial, may help geologists to better grasp the philosophical position of geology with respect to other sciences. The first step was the publication of Steno's Prodromus in 1669, which established the methodological rules for decoding a geologic history from the geometrical arrangements of beds. The second step was the founding of the Geological Society of London in 1807, an act by which a new community recognized itself as a scientific and professional entity applying a novel methodology in the study of Earth. Their approach represented a synthesis of the Wernerian-historical and the Huttonian-causal methods. The third step was the emergence of plate tectonics in 1967, when the actualistic method (i.e. uniformity of laws and processes) could be extended to the interpretation of the whole lithosphere. At the same time, the heuristic power of historical geology was validated by independent, physico-mathematical testing.

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Mississippian polyplacophoran (Mollusca) from Utah

Journal of Paleontology ◽

10.1017/s0022336000019314 ◽

1989 ◽

Vol 63 (2) ◽

pp. 252-252 ◽

Cited By ~ 2

Author(s):

R. D. Hoare

Keyword(s):

North America ◽

Taxonomic Group ◽

Geologic History ◽

Lower Carboniferous ◽

History Of

Reports of Mississippian polyplacophorans from North America are rare. To date only three species, Gryphochiton parvus (Stevens, 1858) and G. elevatus (Kues, 1978), from the Salem Limestone in Indiana, and Elachychiton juxtaterminus Hoare and Mapes, 1985, from the Imo Formation in Arkansas, have been recognized (Smith and Hoare, 1987). Lobarochiton anomalus (Rowley, 1908), from the Louisiana Limestone in Missouri, is now believed to be Devonian in age. European reports of Lower Carboniferous polyplacophorans are much more common, at least 29 species (Hoare and Smith, 1987). The location of any specimen in the Mississippian of North America becomes significant in filling out the geologic history of this taxonomic group.

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