v/eaver: invertebrate paleontology and historical geology 715 



Sponsors of Research and Publication 



During the past one hundred years research and publication of results have 

 been carried on largely by technically trained people associated with national 

 and state surveys, academies of science, organizations with funds available for 

 special problems, and by the geological and paleontological staffs of universities 

 in all parts of the world. The past three decades have witnessed the growing 

 application of earth science to problems connected with the search for oil and 

 gas. As a result, extensive funds have been available for world-wide research 

 and in many instances for the publication of important scientific contributions. 



The national and state geological surveys were established for the purpose of 

 making known information concerning the natural resources in the rocks and 

 the nature of the problems for their utilization. Many of these organizations 

 have devoted their energies to the investigation and publication of problems con- 

 nected with the direct application of geology and paleontology to the develop- 

 ment of mining in its broadest sense. Others have considered the furtherance 

 of research associated with the more purely scientific phases of paleontology as 

 an important function. A large number of these organizations were founded 

 before 1850. 



Historical Geology 1850-1950 



Pre-Cambrian time: Eocks of pre-Cambrian age have a wide areal distribu- 

 tion involving perhaps twenty per cent of the continents and presumably under- 

 lie as a basement complex all the Paleozoic and later formations. Since 1850 

 they have been studied extensively in eastern Canada and in the area of the 

 Great Lakes. Over wide areas these rocks have been divided into two broad 

 groups or systems, which are separated by a profound unconformity. The lower 

 division usually consists of granites, gneisses, and highly metamorphosed sedi- 

 mentary rocks and volcanic products : the upper of metamorphosesd and unmeta- 

 morphosed rocks, including slates, quartzites, graywackes, schists, gneisses, and 

 eruptive rocks. Such materials are well exposed and have been studied in detail 

 by many authors in northern Scotland and described as the lower, or Lewisian, 

 and the upper, or Torridonian, systems. Giimbel proposed a similar twofold divi- 

 sion for the basement rocks in Bavaria and Bohemia and, as in North America, 

 referred to the lower series of gneisses and granite as Archaean and the upper 

 gneisses, schists, limestones, and shales as Algonkian. A similar classification 

 was adopted in 1905 by a committee of thirty-five geologists under the direction 

 of Michel Levy for the geological map of France. The pre-Paleozoic rocks of 

 Scandinavia have a wide areal distribution and, after investigation by Torne- 

 bohm, were divided into two series, as in Great Britain. Sederholm in 1907 

 described an upper, fourfold division of metamorphosed sedimentary rocks as 

 Algonkian; unconformably beneath these were a lower series of granites and 

 gneisses and an upper one of metamorphosed sedimentary rocks. The investiga- 

 tions of von Richthofen in China, followed by those of Bailey Willis and Eliot 

 Blackwelder in 1907, led to a classification somewhat similar to that in the Great 

 Lakes area. In a general way the pre-Cambrian rocks of Western Australia, 

 Africa south of the Sahara, northeastern South America, India, Siberia, and 

 Russia have a similar representation. Certain of the lower formations in Russia 



