 Peter sandstone. Mineral Creek has cut its valley through this sandstone and well down into the underlying limestone, which here has an exposed thickness of more than 100 feet. This latter rock shows evidence of considerable disturbance, being more or...  The Proceedings of the Iowa Academy of Science - Pàgina 38per Iowa Academy of Science - 1895Visualització completa - Sobre aquest llibre
 | Iowa Geological Survey - 1897 - 720 pàgines
...latter rock shows evidence o£ considerable disturbance, being more or less brecciated, and has been recemented by siliceous material. It is full of cherty...short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the drifts extended... | |
 | 1897 - 560 pàgines
...latter rock shows evidence of considerable disturbance, being more or less brecciated, and has been recemented by siliceous material. It is full of cherty...short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the drifts extended... | |
 | 1906 - 734 pàgines
...latter rock shows evidence of considerable disturbance, tjeing more or less brecciated, and has been recemented by siliceous material. It is full of cherty....short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the drifts extended... | |
 | Harry Foster Bain - 1906 - 778 pàgines
...latter rock shows evidence of considerable disturbance, being more or less brecciated, and has been recemented by siliceous material. It is full of cherty,...short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the. drifts... | |
 | Geological Survey (U.S.) - 1906 - 222 pàgines
...latter rock shows evidence of considerable disturbance, being more or less brecciated, and has been recemented by siliceous material. It is full of cherty,...short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the drifts extended... | |
 | William Otis Hotchkiss - 1906 - 372 pàgines
...evidence of considerable disturbance, being more or less brecciated, and has been recemented by siliccous material. It is full of cherty, or flinty, matter...short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the drifts extended... | |
 | Wisconsin Geological and Natural History Survey - 1907 - 192 pàgines
...latter rock shows evidence of considerable disturbance, being more or less brecciated, and has been recemented by siliceous material. It is full of cherty,...short drifts. Instead of being in crevices the ore occurred scattered through the limestone, necessitating considerable blasting. None of the drifts extended... | |
 | Wisconsin Geological and Natural History Survey - 1907 - 188 pàgines
...latter rock shows evidence of considerable disturbance, being more or less breccia ted, and has been recemented by siliceous material. It is full of cherty,...and were worked by means of short drifts. Instead of bolng in crevices the ore occurred scattered through the limestone, necessitating considerable blasting.... | |
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