NJDEP - NJGS - First Annual Report of the Geological Survey of the ...

7accomplish this most successfully, it must call to its aid palmontology,mineralogy, and chemistry.It is by means of the minerals, and organic remains, thattho geologist is enabled to determine the varieties of rocks,and their relative ages--one of the most important considerationsin a practical or economical view, for it is only in particularformations, Rut].of a particular relative age, that valuablemineral deposits occur. For example, in connection with theigneous and metamorphic rocks (azoie), as granite, trap, gneiss,ehloritic_ talcose_ and hornblende slates, beds of quartz andsaccharoidal marbles_ or white crystalline limestone, occur theprincipal metalliferous deposits, as gold, silver, copper, iron,zinc, &c. It is in connection with the aqueous rocks of a certainrelative age, that occur the great coal deposits, &c. Theformer are determined by their lithological character, the latterby thcir organic remains.PALEONTOLOGY.(O_GA._0 nE_x1_80YaNIMXLg A_D PLANT&)ItsImportan_aml_ZatlontoGeoZogy.Paheontolo_ is the science which treats of fossil remains.It has becn satisfactorily proved by geological and pal_eontologicalresearch, that at different periods of time the crust ofthe earth has undergone numerous and various changes; thatat one time it was inhabited by no living being; that the waternof the ocean covered its surface ; that at a certain periodanimals and plants sprang into existence, and after livingthrough a few generations died, leaving their remains entombedin the sedimentary deposits of the ocean's bed. Starting fromthis point, as we ascchd in the scale of animal and vegetableexistence, we find now tribes of animals and plants successivelyappearing and disappearing, generation ssuccecding generations,until finally man and his associates, the most perfectof them all, crown the era of animal existence. Sometribes and species have lived through long and saecessive peri-NEW JERSEY GEOLOGICAL SURVEY