The Geological History of the Isthmus of Panama and Portions of Costa Rica. Robert T. Hill
The Journal of geology
REVIEWS which their existence is known. The throw of these minor faults varies from a few feet to several hundred. The faults enumerated are more frequent in the trap than in the shale and sandstone. Since faults are much more easily detected where they affect the trap, owing to the fact that this formation has come to assume the form of ridges since the faulting, it is inferred that minor faults affecting the more homogeneous portions of the sedimentary part of the system may have escaped
... y have escaped observation. But for the faults, the determination of the thickness of the system would be an easy matter. Allowance can be made for the faults which are known, but there is no way of taking quantitative account of those which have not been discovered. Impressed with the fact that there may be many undiscovered faults of slight extent in the homogeneous shales and sandstones, Dr. Kiimmel has revised his estimate of the thickness of the system, and now gives the following figures: Brunswick series, -----6,ooo to 8,ooo Lockatong series, ----3,500 to 3,600 Stockton series, ----2,300 to 3,o00 I ,8oo to 14,700 The thicknesses of the principal sheets of trap are also given, the thickest being less than one thousand feet. A brief discussion of the conditions of the origin of the system is followed by a resume of its economic resources.