 | Geological Survey (U.S.) - 1909 - 160 Seiten
...for example, a rapid alternation of shale and limestone. * * * The definition of a formation * * * should include a statement of the important facts...identified in the field, whether by geologist or layman. As uniform conditions of deposition were local as well as temporary, it is to be assumed that each... | |
 | Henry Fairfield Osborn, William Diller Matthew - 1909 - 518 Seiten
...alternation of shale and limestone. * The definition of a formation * * should \\\c\\jA*b •»• statement of the important facts which led to its...identified in the field, whether by geologist or layman. As uniform conditions of deposition were local as well as temporary, it is to be assumed that each... | |
 | James H. Shea - 1960 - 300 Seiten
...fundamental unit in the local classification of the rocks** is of little help. It is stated, however, that "the selection of formations shall be such that they...the practical and scientific needs of the users of geologic maps." This concept of the formation as a "convenient mappable unit" seems to be generally... | |
 | 1909 - 738 Seiten
...for example, a rapid alternation of shale and limestone. * * * The definition of a formation * * * should include a statement of the important facts...identified in the field, whether by geologist or layman. As uniform conditions of deposition were local as well as temporary, it is to be assumed that each... | |
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As uniform conditions of deposition were local as well as temporary, it is to be assumed that each formation is limited in horizontal extent. The formation should be recognized and should be called by the same name as far as it can be traced and identified... 