Some Engineering Problems Of The Panama Canal In Their Relation To Geology And Topography

INDEX, 87 J. Page. Jointing of rocks, relåtion of, to engineering problems........................ 34 L. La Boca, Canal Zone, sand and mud from, analyses of....................... 47 La Pita slide, cause of...................... 62 view of................................ 64 Las Cascadas, Culebra Cut, slide at, extent of. 60 view of............................ 60 Las Cascadas agglomerate, description of..... 20 in Canal Zone, extent of................ 20 occurrence of, figure showing....... 18 view of................................ 20 Lava flows, occurrence of, in rock of Canal Zone............................ 30 Limestone, as foundation rock, disadvantages of................................ 38 soft, slope required for.................. 69,70 solubility of, in water.................. 38 Locks, construction of, details of............ 42,43 See also Corozal Locks; Gatun Lock; Pedro Miguel Locks. M. Malonis Island, cracks in basalt at, view of... 34 Masonry for canal, cost of.................. 80 Merrick, A. W., on slide on slopes of Des Moines River.................... 65 Meta-breccia, description of................. 30 occurrence of, in Canal Zone............ 30 figure showing................. 18 uses of................................. 30 Miraflores Dam, excavation for, cost of...... 81 Miraflores Lake, purpose of................. 15 Miraflores Locks, cost of excavation for..... 81 masonry for........................ 80 rock used in construction of............. 28 Monte Lirio, rainfall in..................... 11 Mud from La Boca, analyses of............. 47 N. Naos Island, rock forming, description of.... 28 Naos Island Breakwater, cost of............ 78 P. Pacific division of canal, cost of excavation in. 76,81 masonry for.................... 80 sand for______....................... 79 Panama, earthquake in, effect of............ 75 topography of.......................... 9 Panama Bay, earthquakes at, cause of...... 33 features of............................. 14,15 shallowness of, factors governing........ 15 Panama Canal, construction of............. 7 costs of....______ 76-81 possible danger to, by earthquakes.....74-76 Panama City, rainfall in................... 11 I anama formation, description of........... 26 occurrence of, in Canal Zone............ 26 figure showing................. 18 P araiso, Culebra Cut, slide at, extent of..... 60 2 cdro Miguel, Culebra Cut, slide at, extent of. 60 3 edro Miguel Locks, cost of excavation for... 81 masonry for........................ 80 Page. Pedro Miguel Locks, foundations of, descrip- tion of........................... 45 rock used in construction of............ 28 sites of, description of.................. 45,46 Pleistocene formations, description of....... 26 occurrence of, in Canal Zone............ 26 figure showing.................. 18 Portland, Oreg., slide near, cause of........ 64 relation of, to rainfall.................... 64 remedy for.........................G4,65 Porto Bello, rainfall in..................... 11 Porto Bello Harbor, features of............. 15 Porto Bello quarry, rock from, cost of....... 77 description of...................... 36 use of.............................. 34 Prism, excavation of, cost of................ 81 Pyrite, as cause of heating of ground........ 73,74 R. Rainfall in Canal Zone, amount of.......... 11 Rhyolite, description of.................... 28,29 occurrence of, in Canal Zone............ 28 figure showing.................. 18 uses of................................. 28,29 Rice, G. S., bibliography on slides by....... 70,71 Rock, cost of breaking, factors affecting..... 16 crumbling of, in excavation, causes of.... 52 crushed, size of, factors governing....... 16,19 crushing strength of, relation of, to slides. 50 deforming, slopes required for.........'.. 68 resistance of, factors affecting........... 19 sloughing of, conditions governing......66,67 soft, excavations in, effect of............51,52 slopes required for...................... 69,70 tensile strength of, relation of, to slides... 50,51 volcanic-clay, slopes required for........C9,70 See also Bedded rocks; Igneous rocks. Rock formations in Canal Zone, description of. 19-31 types of................................ 16 See also formations named. Rock material for canal construction, sources of_____....._______........______......._____..... - - - - 36~38 types of............................ 35 S. Sand, analyses of........................... 47 for canal construction, cost of........... 79 use of.............................. 35 Sandstones, soft, slopes required for........69,70 Saville, C. M., instrument of, for recording earth vibrations.................. 54 Shales, lignitic, slopes required for..........69,70 soft, slopes required for.................69,70 Shearing in rocks of Canal Zone, extent of... - 32,33 Slides, bibliography on..................... 70,71 causes of...............................50-54 discussion of............................48-71 fault-zone, discussion of.................61,62 occurrence of....................... 62 from excavations, extent of, factors gov- erning............................49,50 from structural breaks, extent of........ 57 gravity .'-ctors causing................. 60 fe r s of.......................... 60 ii. dy for......................... 60 vi. of............................. 60