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• 1. [Article] The Ore Bin ; Vol. 38 No. 5 (May 1976)

  Average annual losses caused by geologic hazards in Oregon are difficult to determine, owing to incomplete and scattered data. Preliminary considerations, however, indicate that losses to landslides may ...

  Citation × Citation Citation Abstract Copy Title: The Ore Bin ; Vol. 38 No. 5 (May 1976) Author: Beaulieu, John D., Oregon. Dept. of Geology and Mineral Industries Average annual losses caused by geologic hazards in Oregon are difficult to determine, owing to incomplete and scattered data. Preliminary considerations, however, indicate that losses to landslides may total between $4 million and $40 million per year. As many as nine persons have been killed by one landslide in Oregon in recent years. Losses through coastal retreat have totaled millions of dollars as large parts of major communities have been destroyed. Tsunami damage totals approximately $1 million and would probably be far greater were it not for the fortunate timing of the 1964 tsunami. Flood losses will average $36 million per year by the year 2000. Because this hazard is so large and complex, it is dealt with by several state and Federal agencies. Volcanic and earthquake hazards constitute long-range threats, with the potential for catastrophic consequences. Specific identifications of these hazards and long-range mitigative efforts can reduce the risk considerably. It is the aim of a good hazards investigation to regard not only the historic distribution of hazards but also the causes and the distribution of hazardous antecedent conditions. The net result is the generation of information that is more than purely a descriptive account of past events, but which is also a predictive tool for evaluating the impacts of contemplated changes in land use. In this way, the information becomes a powerful land-management tool. Effective mitigation and planning can only proceed on a firm foundation of accurate hazards analysis and mapping. The aim of the geologic hazards program at the Oregon Department of Geology and Mineral Industries is to provide objective and accurate data, free of personal value judgments. The purpose is to provide government with an array of appropriate uses for land in hazardous areas, based on adequate information and on unbiased investigation. Title: The Ore Bin ; Vol. 38 No. 5 (May 1976) Author: Beaulieu, John D., Oregon. Dept. of Geology and Mineral Industries Average annual losses caused by geologic hazards in Oregon are difficult to determine, owing to incomplete and scattered data. Preliminary considerations, however, indicate that losses to landslides may total between $4 million and $40 million per year. As many as nine persons have been killed by one landslide in Oregon in recent years. Losses through coastal retreat have totaled millions of dollars as large parts of major communities have been destroyed. Tsunami damage totals approximately $1 million and would probably be far greater were it not for the fortunate timing of the 1964 tsunami. Flood losses will average $36 million per year by the year 2000. Because this hazard is so large and complex, it is dealt with by several state and Federal agencies. Volcanic and earthquake hazards constitute long-range threats, with the potential for catastrophic consequences. Specific identifications of these hazards and long-range mitigative efforts can reduce the risk considerably. It is the aim of a good hazards investigation to regard not only the historic distribution of hazards but also the causes and the distribution of hazardous antecedent conditions. The net result is the generation of information that is more than purely a descriptive account of past events, but which is also a predictive tool for evaluating the impacts of contemplated changes in land use. In this way, the information becomes a powerful land-management tool. Effective mitigation and planning can only proceed on a firm foundation of accurate hazards analysis and mapping. The aim of the geologic hazards program at the Oregon Department of Geology and Mineral Industries is to provide objective and accurate data, free of personal value judgments. The purpose is to provide government with an array of appropriate uses for land in hazardous areas, based on adequate information and on unbiased investigation. Close

• 2. [Article] The Ore bin ; Vol. 34 No. 8 (August 1972)

  The plate tectonic history of Oregon is but one piece of a worldwide jigsaw puzzle encompassing much of geologic time. With the splitting of Pangaea in Mesozoic times, Oregon has occupied the leading edge ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 34 No. 8 (August 1972) Author: Beaulieu, John D., Oregon. Dept. of Geology and Mineral Industries The plate tectonic history of Oregon is but one piece of a worldwide jigsaw puzzle encompassing much of geologic time. With the splitting of Pangaea in Mesozoic times, Oregon has occupied the leading edge of the North American Plate as it has impinged upon the ancestral oceanic East Pacific Plate. In the process Oregon has undergone profound subduction type tectonism. In addition, it may have acquired much lithospheric material from other plates, possibly some of the Paleozoic rocks of the Klamaths from Asia, ultramafic rocks and volcanic rocks from the Triassic oceanic crust, and the Siletz River Volcanics from the Eocene deep-sea floor. In middle Tertiary times, Oregon, along with the rest of western North America, actually caught up with the East Pacific Rise, an event which profoundly altered the pattern of tectonic behavior within the state. Flood basalts and block faulting replaced andesitic volcanism and thrust faulting as the dominant mode of tectonism. The pattern of deformation in late Tertiary times is extremely complex and a plate tectonic model consistent with all the data has yet to be formulated. Title: The Ore bin ; Vol. 34 No. 8 (August 1972) Author: Beaulieu, John D., Oregon. Dept. of Geology and Mineral Industries The plate tectonic history of Oregon is but one piece of a worldwide jigsaw puzzle encompassing much of geologic time. With the splitting of Pangaea in Mesozoic times, Oregon has occupied the leading edge of the North American Plate as it has impinged upon the ancestral oceanic East Pacific Plate. In the process Oregon has undergone profound subduction type tectonism. In addition, it may have acquired much lithospheric material from other plates, possibly some of the Paleozoic rocks of the Klamaths from Asia, ultramafic rocks and volcanic rocks from the Triassic oceanic crust, and the Siletz River Volcanics from the Eocene deep-sea floor. In middle Tertiary times, Oregon, along with the rest of western North America, actually caught up with the East Pacific Rise, an event which profoundly altered the pattern of tectonic behavior within the state. Flood basalts and block faulting replaced andesitic volcanism and thrust faulting as the dominant mode of tectonism. The pattern of deformation in late Tertiary times is extremely complex and a plate tectonic model consistent with all the data has yet to be formulated. Close