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

86 INDEX Page. Culebra Cut, slides in, location of........... 60 possible danger from............... 48,49 remedy for............................ 56 study of............................... 8 types of........................... 54-66 view of............................... 64 terracing on, view of..................... 58 views of............................... 48,52 Culebra formation, description of.......... 21,22 in Canal Zone, extent of.................. 21 occurrence of......................... 21 figure showing................... 18 view of................................... 22 Culebra Island, rock forming, description of.. 28 Cunette, Culebra Cut, slide at, extent of.. 60 D. Dacite, description of........................ 27 uses of................................... 27 Dams, leakage of, determination of......... 38,39 masonry, construction of, factors govern- ing ................................ 38 See also Corozal Dam; Gatun Dam. Deformations, rock, in Culebra Cut, causes of 55,56 description of............................ 54,55 Des Moines River, Iowa, slide on slopes of... 65 Diorite, description of....................... 27 occurrence of, in Canal Zone.............. 27 figure showing.................... 18 Dredging of canal, cost of.................... 81 E. Earth tremors, effect of, on slides........... 53 Earthquakes at Panama Bay, cause of........ 33 in Canal Zone, discussion of........... 74-76 Emperador limestone, description of........ 24 occurrence of, in Canal Zone.............. 24 figure showing.................... 18 view of................................... 24 Empire, Culebra Cut, slide near, cause of.... 62 extent of......................... 60 view of........................... 66 Erosion, slides caused by..................... 63 remedy for............................ 63 E xcavation, dry, cos t of.................... 76 for cana 1, detailed costs of........... 81 extent of, data on............... 81,82 Excavations, cost of. factors determining.... 7 deformations resulting from, figure show- ing........................................ 50,51 slides caused by, factors governing.... 49,50 slopes required for....................... 68 condition5 governing..............66,67 stresses caused by........................ 49 figure showing..........,............. 49 F. Fault zone near Culebra, view of.............. 58 Fault zone slides. See Slides. Faulting in rocks of Canal Zone, extent of.... 32,33 relation of, to engineering.,............. 33 Faults across canal, figure showing........... 17 effect of................................. 58 view of................................... 56 Fissuring of rocks, relation of, to engineering problems..................................... 34 Folding of rocks in Canal Zone, discussion of. 32 G. Page. Gaillard, D. D., on excavations for Panama Canal.................................... 81,82 on heated ground in Culebra Cut...........71-74 Gatun Dam, construction of, difficulties in.. 42 factors affecting.....................40,41 cross section of, figure showing............ 42 excavation of, cost of...................... 81 sizerof..................................... 42 type of, factors determining................ 41 Gatun formation, description of.............. 25,40 occurrence of, in Canal Zone................ 25 figure showing....................... 18 Gatun Lake, bedrock of, strength of.......40,41 formation of................................ 13 position of...............................39,40 waste water from, use of.................... 13 Gatun locks, construction of..................42,43 excavation of, cost of.................... 81 foundations for, description of...........43,44 tests of............................. 43,44 masonry for, cost of........................ 80 Gatun Spillway, excavation of, cost of.... 81 Geologic conditions, knowledge of, value of.. 7 Goethals, G. W., acknowledgments to....... 8 Gold Hill, fault plane at....................... 58 view of................................. 60 rock forming, description of................ 29 stability of, reason for................. 56,57 discussion of........................ 57,58 structure of................................ 58 See also Culebra Cut. Granodiorite, description of.................... 27 occurrence of, in Canal Zone................ 27 figure showing..................... 18 uses of..................................... 27 Gravel, in Canal Zone streams, character of.. 37,38 use of, in canal construction........... 35 Gravity slides. See Slides. Ground water in clay, as cause of slides..52,53 H. Harbors in Canal Zone, general character of.. 14,15 Hayes, C. W., work of............................ 8 Heating of ground, causes of.............. 72,73 Hill, R. T., on geology of Isthmus of Panama. 8,22 Hill type of topography, description of...... 9 development of, i n Canal Zone............... 9 relation of, to construction of canal. 9 view of..................................... 10 Howe, Ernest, on channel of Chagres River.. 44,45 on geology of Isthmus of Panama....... 8,22 on locks aud dams of Panama Canal.....43-47 I. Igneous rocks in Canal Zone, figure showing. 18 use of, in canal construction............... 35 See also, Rocks. Intrusion in rocks of Canal Zone................ 35 Isthmian Canal Commission, acknowledg- ments to............................ 8 Isthmus of Panama, geologic section across, fl gure showing.................... 17 geology of................................... 8 relation of, to engineering problems.. 16-31 stability of, discussion of......... 31 topography of, types of............ 9,10 See also Canal Zone.