A ground water inventory made for a basin area of about\r\n51 square miles and situated 6 miles southeast from Redlands, California,\r\ndisclosed that a mean annual recharge of 4322.5 acre-feet from\r\nrainfall on foothill and mountain areas plus a mean annual deep penetration\r\nvolume of 1693 acre-feet from water artificially applied (irrigation\r\nand domestic uses) are exceeded by local consumptive uses plus exportation\r\nlosses. Detailed studies showed that no appreciable contribution from\r\nrainfall in irrigated and non-irrigated valley lands occurs to the\r\nsub-surface ground water body.
\r\n\r\nElimination of the net basin drawdown loss caused by\r\nexportation will still put the overdraft within the order of 3000\r\nacre-feet per year. An inevitable increase of land cultivation brings\r\nabout no chance to mitigate that figure in the near future.
\r\n\r\nIncreasing volumes of water extraction are shown by a mean\r\nannual drop in water level of wells, from 1.67 feet for the period\r\n1927-1942 to 7.5 feet for the period 1942-1954.
\r\n\r\nAn estimated specific yield of 0.1085 for the ground water\r\nreservoir places the time-life of Yucaipa basin within 35 years,\r\nassuming the existence of a 250 feet thick aquifer under the 400 feet\r\ndeepest wells.
\r\n\r\nA depth of 650-750 feet in water wells is arbitrarily\r\nestablished as a limit for the economic and profitable exploitation\r\nof the basin.
\r\n\r\nA conservative figure of 5000 acre-feet plus minus 1000\r\nacre-feet safe yield is based on the mean annual recharge to valley\r\nlands from foothill and mountain areas. This quantity is likely to be\r\nincreased by additional yields from the aquifer, upon rebounding and \r\nexpansion.
\r\n\r\nThe low porosity value and its close specific yield (0.12 and\r\n0.1085 respectively) associated with a rather low specific retention\r\nvalue, seem to indicate that the hydrological properties of the \r\nYucaipa aquifers reflect the existence of a type of rock near to a\r\nsandy gravel, with locally abundant interstitial materials. \r\nPlio-Pleistocene(?) San Timoteo bed can well appear in Yucaipa basin\r\nat aquifer depths. Younger Quaternary fanglomerates, stream gravels,\r\nweathered soils and modern alluvium occur widely distributed in the\r\nsurface area of Yucaipa. These sediments are bordered to the north,\r\neast, and southeast by hills and mountains of basement complex rocks\r\nwhich are probably pre-Cambrian, but most certainly pre-Cretaceous in \r\nage.
" }, { "name": "Quigley, Milner Darwin", "degree": "Engineering Degree", "year": "1950", "title": "A Restudy of Existing Graphical Methods of Interpreting Magnetic Data and their Application to Interpreting the Results of Magnetic Surveys Across the Los Angeles Basin", "advisor": "Potapenko, Gennady W.", "url": "https://resolver.caltech.edu/CaltechTHESIS:02262010-092659807", "creators": [ { "name": { "family": "Quigley", "given": "Milner Darwin" }, "id": "Quigley-Milner-Darwin", "display_name": "Quigley, Milner Darwin" } ], "advisors": [ { "name": { "family": "Potapenko", "given": "Gennady W." }, "id": "Potapenko-G-W", "role": "advisor", "display_name": "Potapenko, Gennady W." } ], "committee": [ { "name": { "family": "Unknown", "given": "Unknown" }, "display_name": "Unknown, Unknown" } ], "option_major": [ "geophys" ], "doi": "10.7907/KWMD-SQ93", "abstract": "This thesis discusses the historical development of the methods of magnetic interpretation and explains why greater emphasis should be placed on graphical methods. Many graphical methods have been published but only one of them, Pirson's Polar Diagram method, has widespread application to all magnetic interpretive problems.\r\n\r\nThe Polar Diagram method is especially applicable to magnetic problems of a regional nature where the disturbing body is very irregular in shape and cannot be approximated by a second order geometric form. A disturbing body of this description is present in the Los Angeles Basin.\r\n\t\r\nPrevious attempts to match the observed magnetic anomaly curves across the Los Angeles Basin with the theoretical calculated curves by numerical methods have failed to obtain a close comparison. The Polar Diagram method makes it possible to obtain a superposition of the calculated curves over the observed curves except in the vicinity of the Palos Verde Hills. The superposition was obtained only after there was complete agreement between the existing geologic, gravity; and seismic information along the profile across the Basin.\r\n\r\nThe Polar Diagram method is one of the quickest and most straight forward of the graphical methods to use. It is applicable to most magnetic problems where the direction of the induced magnetism is parallel to the direction of the remanent magnetism.\r\n" }, { "name": "Geldart, Lloyd Philip", "degree": "Engineering Degree", "year": "1949", "title": "Periodic Variations of the Gravitational Force. A Gravity Survey in the Monk Hill Area. Transmission of Shot Impulses in Shallow Water", "advisor": "Dix, Charles Hewitt", "url": "https://resolver.caltech.edu/CaltechTHESIS:08172010-101104666", "creators": [ { "name": { "family": "Geldart", "given": "Lloyd Philip" }, "id": "Geldart-Lloyd-Philip", "display_name": "Geldart, Lloyd Philip" } ], "advisors": [ { "name": { "family": "Dix", "given": "Charles Hewitt" }, "id": "Dix-C-H", "role": "advisor", "display_name": "Dix, Charles Hewitt" } ], "committee": [ { "name": { "family": "Unknown", "given": "Unknown" }, "display_name": "Unknown, Unknown" } ], "option_major": [ "geophys" ], "doi": "10.7907/YH1P-CT82", "abstract": "Part I: \r\nUsing a La Coste and Romberg gravimeter, readings were taken every half hour for 72 hours immediately preceding full moon in the sub-basement of Mudd Building, California Institute of Technology, and for 56 hours immediately following in the interferometer building on Mount Wilson. Observed values were compared with values calculated on the hypothesis of a rigid earth, the results showing more yielding at Mount Wilson (22%) than at Mudd Building (16%). Effects due to ocean tides and barometric changes were estimated. After the removal of drift and earth tide effects, the residuals showed periods of 24, 12, 6, and 2 hours, the 24 hour period being very strong at Mount Wilson.
\r\n\r\nPart II: \r\nUsing a La Coste and Rombert gravimeter, gravity values were obtained at 65 stations in the vicinity of Monk Hill, Pasadena. A density value for elevation corrections was obtained using a least squares method and data obtained with a network of 35 stations in Washington Park. A topographical correction was also made for the San Gabriel Mountains to the north of the area.
\t\r\n\r\nThe corrected gravity data were used to calculate elevations of the basement along Howard Street, and the resulting basement profile compared with one obtained by a seismograph survey.
\r\n\r\nPart III: \r\nThe properties of various types of waves set up by underwater explosions is discussed from the viewpoint of their application in locating shot points in seismic work carried on over water. The construction of the audio amplifiers and filters used to record these waves is described, together with the results of a preliminary check of their performance.
\r\n" }, { "name": "Y\u00fcng\u00fcl, Sulhi", "degree": "Engineering Degree", "year": "1945", "title": "Some Uses of the Spontaneous Polarization Method", "advisor": "Potapenko, Gennady W.", "url": "https://resolver.caltech.edu/CaltechTHESIS:12222015-094656971", "creators": [ { "name": { "family": "Y\u00fcng\u00fcl", "given": "Sulhi" }, "id": "Y\u00fcng\u00fcl-Sulhi", "display_name": "Y\u00fcng\u00fcl, Sulhi" } ], "advisors": [ { "name": { "family": "Potapenko", "given": "Gennady W." }, "id": "Potapenko-G-W", "role": "advisor", "display_name": "Potapenko, Gennady W." } ], "committee": [ { "name": { "family": "Unknown", "given": "Unknown" }, "display_name": "Unknown, Unknown" } ], "option_major": [ "geophys" ], "doi": "10.7907/WHXG-6T26", "abstract": "As a partial fulfillment of the requirements in obtaining a Professional\r\nDegree in Geophysical Engineering at the California Institute of Technology.\r\nSpontaneous Polarization method of electrical exploration was chosen\r\nas the subject of this thesis. It is also known as \"self potential electrical\r\nprospecting\" and \"natural currents method.\"
\r\n\r\nThe object of this thesis is to present a spontaneous polarization exploration\r\nwork done by the writer, and to apply analytical interpretation methods\r\nto these field results.
\r\n\r\nThe writer was confronted with the difficulty of finding the necessary\r\ninformation in a complete paper about this method. The available papers are\r\nall too short and repeat the usual information, giving the same examples.\r\nThe decision was made to write a comprehensive paper first, including the \r\nwriter's experience, and then to present the main object of the thesis.
\r\n\r\nThe following paper comprises three major parts:
\r\n\r\n1 - A comprehensive treatment of the spontaneous polarization method.
\r\n2 - Report of the field work.
\r\n3 - Analytical interpretation of the field work results.
The main reason in choosing this subject is that this method is the\r\nmost reliable, easiest and requires the least equipment in prospecting for\r\nsulphide orebodies on unexplored, rough terrains.
\r\n\r\nThe intention of the writer in compiling the theoretical and analytical \r\ninformation has been mainly to prepare a reference paper about this method.
\r\n\r\nThe writer wishes to express his appreciation to Dr. G. W. Potapenko,\r\nAssociate Professor of Physics at California Institute of Technology, for\r\nhis generous help.
" } ]