and eras. Each of the latter are subdivided into formations that are usually of one kind of rock, but these subdivisions differ widely in the different continents and in the different regions of the same continent. At the same period of geologic time the deposition of limestone may have been in progress at one place; of sandstone or shale at another, etc. Consequently, it would be impossible to give here all of the numerous formations found in the United States.3 GENERAL TABLE OF GEOLOGIC TIME DIVISIONS 4 Both of the preceding classes of rocks are subject to alteration and change of mineralogical composition and texture, etc., by the action of heat, water, solutions, pressure, and other agents. 3 See Chamberlin & Salisbury's Geology, Vol. III, Appendix, which gives numerous sections from all parts of the United States. 4 From Chamberlin & Salisbury, vol. 2, p. 160. The formations below the Cambrian are those proposed by the joint committee of the United States and Canadian Geological Surveys as given on p. 161 of Chamberlin & Salisbury's work, instead of the corresponding subdivisions on p. 160. It is probable that the method of subdivision and names proposed by said joint committee will be more generally used hereafter. Thus limestone is altered to marble; deposits of vegetable matter to peat, lignite, bituminous or anthracite coal; clay and shale to slate; sandstone to schist and quartzite; granite and other crystalline rocks to gneiss, etc. No complete classification of the metamorphic rocks has been proposed and, indeed, this is hardly possible on account of the diverse source of the original material of the rocks and the varying agents that may have produced the alteration in the rocks. Consult Kemp's Handbook and other works on petrology. In addition to the books on petrology described in the Bibliography, p. 560, the books of Luquer and Iddings, mentioned under the title, mineralogy, p. 559, will be found useful on the metamorphic and igneous rocks. There is no separate work on the sedimentary rocks. They are treated in the works on general geology and also in Kemp's Handbook. The most thorough treatment of their classification, etc., is an article by Dr. A. W. Grabau in the American Geologist, April, 1904, p. 228. They are also given full consideration in Dr. Grabau's Principles of Stratigraphy, described on p. 562. INDEX In consulting the index on any subject which may be a subject of State Where the reference is to a section as well as a page, the section numbers: For a table showing by consecutive numbers the pages on which are found certified copy of judgment to be filed Sec. 85, 374 Adverse claims notice, contents parties notified by register, etc.... Advertising out. . . . Affidavit of citizenship, where made. posting survey plat and notice. Affidavits of representation work in Alaska, verification of ... Agate, land containing regarded as mineral Agricultural entries. PAGE 348 Sec. 81, 373 .Sec. 83, 373 Sec. 82, 373 126 Secs. 69 and 70, 357 324 forfeiture, etc. 60 Amendment to Sec. 2325, 363 109 105 mineral locations by mining laws extended to, 9; Act May 17, 1884, recording affidavit of representation work Act Mar. 2, 1907, 395 mining locations, etc.. Act June 6, 1900, 391 American mining law, sources of Amygdaloid bands, land containing regarded as mineral. Ancient buried placers. ... 7 60 568 12 279 Andromeda, great nebula of 86 Angles 146 Annual expenditure of $100, matter between rival claimants Sec. 55, 370 labor .123; Sec. 2324, 359; Sec. 12, 361 |
