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• 1. [Article] The Ore bin ; Vol. 36 No. 3 (March 1974)

  Wright's Point, a 250-foot-high, sinuous, flat-topped ridge, projects eastward into Harney Basin, Harney County, Oregon. This 6-mile-long feature ranges from 200 to 600 yards wide and merges with a broad ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 36 No. 3 (March 1974) Author: Niem, Alan R., Oregon. Dept. of Geology and Mineral Industries Wright's Point, a 250-foot-high, sinuous, flat-topped ridge, projects eastward into Harney Basin, Harney County, Oregon. This 6-mile-long feature ranges from 200 to 600 yards wide and merges with a broad mesa at its western end. The nearest topographic highs are Dog Mountain, 2 miles southwest, and foothills of the Blue Mountains near Burns, 12 miles northwest. The point is composed of a fluvial sequence of tuffaceous channel sandstones, mudstones, and conglomerates (Pliocene-Pleistocene Harney Formation) capped by two thin, early Pleistocene diktytaxitic olivine basalt flows. The configuration of the ridge and the paleocurrent pattern, sedimentary structures, fossils, and stratigraphic relations of the rocks to nearby topographic highs suggest that the fluvial sequence and capping basalts were deposited in a narrow valley of an eastward flowing meandering stream(s). The basalts acted as a protective cap while the less-resistant valley walls were eroded away to produce an inverted topography. Remnants of the valley walls consist of a Plio-Pleistocene palagonite tuff ring at Dog Mountain and ignimbrites and tuffaceous sediments of the middle Pliocene Danforth Formation in the Blue Mountain foothills. Reworked palagonite tuff, pumice sands, and Danforth ignimbrite pebbles compose the sandstone and conglomerates of Wright's Point. Measured elevation differences at the base of the lower flow, orientations of filled and open lava tubes, and increasing number of flows to the west suggest that the basalt flowed from west to east down the stream valley. Probable sources of the basalts are several vents 6 miles west of Wright's Point near the Palomino Buttes. Title: The Ore bin ; Vol. 36 No. 3 (March 1974) Author: Niem, Alan R., Oregon. Dept. of Geology and Mineral Industries Wright's Point, a 250-foot-high, sinuous, flat-topped ridge, projects eastward into Harney Basin, Harney County, Oregon. This 6-mile-long feature ranges from 200 to 600 yards wide and merges with a broad mesa at its western end. The nearest topographic highs are Dog Mountain, 2 miles southwest, and foothills of the Blue Mountains near Burns, 12 miles northwest. The point is composed of a fluvial sequence of tuffaceous channel sandstones, mudstones, and conglomerates (Pliocene-Pleistocene Harney Formation) capped by two thin, early Pleistocene diktytaxitic olivine basalt flows. The configuration of the ridge and the paleocurrent pattern, sedimentary structures, fossils, and stratigraphic relations of the rocks to nearby topographic highs suggest that the fluvial sequence and capping basalts were deposited in a narrow valley of an eastward flowing meandering stream(s). The basalts acted as a protective cap while the less-resistant valley walls were eroded away to produce an inverted topography. Remnants of the valley walls consist of a Plio-Pleistocene palagonite tuff ring at Dog Mountain and ignimbrites and tuffaceous sediments of the middle Pliocene Danforth Formation in the Blue Mountain foothills. Reworked palagonite tuff, pumice sands, and Danforth ignimbrite pebbles compose the sandstone and conglomerates of Wright's Point. Measured elevation differences at the base of the lower flow, orientations of filled and open lava tubes, and increasing number of flows to the west suggest that the basalt flowed from west to east down the stream valley. Probable sources of the basalts are several vents 6 miles west of Wright's Point near the Palomino Buttes. Close

• 2. [Article] The Ore bin ; Vol. 28 No. 11 (November 1966)

  Introduction -- Stratigraphy -- Pre-Tertiary rocks -- Umpqua Formation -- Tyee Formation -- Pre-Coaledo - Post-Tyee beds -- Coaledo Formation -- Bastendorff Formation -- Tunnel Point Formation -- Miocene ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 28 No. 11 (November 1966) Author: Oregon. Dept. of Geology and Mineral Industries, Baldwin, Ewart Merlin, 1915- Introduction -- Stratigraphy -- Pre-Tertiary rocks -- Umpqua Formation -- Tyee Formation -- Pre-Coaledo - Post-Tyee beds -- Coaledo Formation -- Bastendorff Formation -- Tunnel Point Formation -- Miocene beds -- Empire Formation -- Coquille Formation -- Pleistocene terraces -- Structural geology -- Faulting -- Folding and warping -- Bibliography. Title: The Ore bin ; Vol. 28 No. 11 (November 1966) Author: Oregon. Dept. of Geology and Mineral Industries, Baldwin, Ewart Merlin, 1915- Introduction -- Stratigraphy -- Pre-Tertiary rocks -- Umpqua Formation -- Tyee Formation -- Pre-Coaledo - Post-Tyee beds -- Coaledo Formation -- Bastendorff Formation -- Tunnel Point Formation -- Miocene beds -- Empire Formation -- Coquille Formation -- Pleistocene terraces -- Structural geology -- Faulting -- Folding and warping -- Bibliography. Close

• 3. [Article] The Ore bin ; Vol. 25 No. 4 (April 1963)

  Introduction -- Seismology -- Recording stations -- Travel-time curve -- Main earthquake -- Epicenter and origin time -- Magnitude and intensity -- Depth of focus -- Source motion -- Aftershocks -- Geology ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 25 No. 4 (April 1963) Author: Dehlinger, Peter, Chiburis, E. F., Bowen, Richard G., Oregon. Dept. of Geology and Mineral Industries, Westphal, Warren H. Introduction -- Seismology -- Recording stations -- Travel-time curve -- Main earthquake -- Epicenter and origin time -- Magnitude and intensity -- Depth of focus -- Source motion -- Aftershocks -- Geology -- Stratigraphy -- Gable Volcanics -- Oligocene marine sedimentary rocks -- Columbia River basalt -- Plio-Pleistocene rocks -- Recent alluvium -- Structure -- Recommendations -- Acknowledgements -- References Title: The Ore bin ; Vol. 25 No. 4 (April 1963) Author: Dehlinger, Peter, Chiburis, E. F., Bowen, Richard G., Oregon. Dept. of Geology and Mineral Industries, Westphal, Warren H. Introduction -- Seismology -- Recording stations -- Travel-time curve -- Main earthquake -- Epicenter and origin time -- Magnitude and intensity -- Depth of focus -- Source motion -- Aftershocks -- Geology -- Stratigraphy -- Gable Volcanics -- Oligocene marine sedimentary rocks -- Columbia River basalt -- Plio-Pleistocene rocks -- Recent alluvium -- Structure -- Recommendations -- Acknowledgements -- References Close

• 4. [Article] The Ore Bin ; Vol. 34 No. 5 (May 1972)

  The Oregon Coast between Yachats and Newport is a narrow, slightly elevated coastal plain. With the exceptions of basalt rock at Yachats and Seal Rock, the bedrock along this segment of the coast is sedimentary. ...

  Citation × Citation Citation Abstract Copy Title: The Ore Bin ; Vol. 34 No. 5 (May 1972) Author: Lund, Ernest H., Oregon. Dept. of Geology and Mineral Industries The Oregon Coast between Yachats and Newport is a narrow, slightly elevated coastal plain. With the exceptions of basalt rock at Yachats and Seal Rock, the bedrock along this segment of the coast is sedimentary. Several Pleistocene marine terrace levels are discernible at places along the plain, and sand dunes, both active and stabilized, impart a rolling topography to most of it. Numerous streams have incised small valleys and ravines into its surface; at Waldport the plain is interrupted by the estuary of the Alsea River and at Ona Beach State Park by the alluvial plain of Beaver Creek. Except in the two localities where basalt is exposed, the shore is marked by long stretches of sandy beaches bounded by low sea cliffs. Where the basalt is exposed, the shore has the rugged features that are characteristic of Oregon shores bounded by this type of rock. Title: The Ore Bin ; Vol. 34 No. 5 (May 1972) Author: Lund, Ernest H., Oregon. Dept. of Geology and Mineral Industries The Oregon Coast between Yachats and Newport is a narrow, slightly elevated coastal plain. With the exceptions of basalt rock at Yachats and Seal Rock, the bedrock along this segment of the coast is sedimentary. Several Pleistocene marine terrace levels are discernible at places along the plain, and sand dunes, both active and stabilized, impart a rolling topography to most of it. Numerous streams have incised small valleys and ravines into its surface; at Waldport the plain is interrupted by the estuary of the Alsea River and at Ona Beach State Park by the alluvial plain of Beaver Creek. Except in the two localities where basalt is exposed, the shore is marked by long stretches of sandy beaches bounded by low sea cliffs. Where the basalt is exposed, the shore has the rugged features that are characteristic of Oregon shores bounded by this type of rock. Close

• 5. [Article] The Ore bin ; Vol. 33 No. 2 (February 1971)

  The 26-mile stretch of shore extending from Florence to Yachats is one of the most rugged and scenic parts of the Oregon Coast. Along most of this part of the coast the shore is bounded by basalt bedrock ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 33 No. 2 (February 1971) Author: Lund, Ernest H., Oregon. Dept. of Geology and Mineral Industries The 26-mile stretch of shore extending from Florence to Yachats is one of the most rugged and scenic parts of the Oregon Coast. Along most of this part of the coast the shore is bounded by basalt bedrock of varied types. Through differential erosion of the basalt, the many landforms, such as headlands, rocky shores, reefs, and sea stacks, that impart the rugged character to the coast have been and are still in the process of being developed. In places where the basalt bedrock is least resistant to erosion, small embayments with bay-head beaches have been formed, and areas where the bedrock is sedimentary are characterized by coastal plains as much as 4 miles wide. The larger areas of coastal plain are also areas of sand dunes; here the surface configuration is attributed to dune development that has gone on from late Pleistocene to the present. Title: The Ore bin ; Vol. 33 No. 2 (February 1971) Author: Lund, Ernest H., Oregon. Dept. of Geology and Mineral Industries The 26-mile stretch of shore extending from Florence to Yachats is one of the most rugged and scenic parts of the Oregon Coast. Along most of this part of the coast the shore is bounded by basalt bedrock of varied types. Through differential erosion of the basalt, the many landforms, such as headlands, rocky shores, reefs, and sea stacks, that impart the rugged character to the coast have been and are still in the process of being developed. In places where the basalt bedrock is least resistant to erosion, small embayments with bay-head beaches have been formed, and areas where the bedrock is sedimentary are characterized by coastal plains as much as 4 miles wide. The larger areas of coastal plain are also areas of sand dunes; here the surface configuration is attributed to dune development that has gone on from late Pleistocene to the present. Close

• 6. [Article] The Ore bin ; Vol. 32 No. 6 (June 1970)

  Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated ...

  Citation × Citation Citation Abstract Copy Title: The Ore bin ; Vol. 32 No. 6 (June 1970) Author: Walker, George Walton, 1921-, Oregon. Dept. of Geology and Mineral Industries Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated patches elsewhere in the state appear to have been spared these recurring inundations. Eruptions occurred at different times throughout the Cenozoic, and for purposes of description, they can be separated into three age groups: an older one of Eocene, Oligocene, and Miocene age, an intermediate one of early and middle Pliocene age, and a young group of late Pliocene, Pleistocene, and Holocene age. Some of these ash-flow tuffs are of small volume, less than a cubic mile, and are related to fissure vents, small domal complexes, or calderas from which several kinds of volcanic products were erupted. A few cover thousands of square miles, have volumes of tens of cubic miles, and apparently are related to a large-scale basinal collapse structure and associated calderas. Most ash-flow tuffs are rhyolite or dacite; a few are peralkaline soda rhyolite. Older ash-flow tuffs are commonly diagenetically altered to a variety of secondary minerals; of the younger tuffs, only those that erupted into shallow lakes exhibit comparable alteration. Title: The Ore bin ; Vol. 32 No. 6 (June 1970) Author: Walker, George Walton, 1921-, Oregon. Dept. of Geology and Mineral Industries Periodic violent eruptions from many different centers during Cenozoic time deposited vast quantities of pyroclastic material as ash-flow tuffs over most of Oregon, although the Coast Ranges and isolated patches elsewhere in the state appear to have been spared these recurring inundations. Eruptions occurred at different times throughout the Cenozoic, and for purposes of description, they can be separated into three age groups: an older one of Eocene, Oligocene, and Miocene age, an intermediate one of early and middle Pliocene age, and a young group of late Pliocene, Pleistocene, and Holocene age. Some of these ash-flow tuffs are of small volume, less than a cubic mile, and are related to fissure vents, small domal complexes, or calderas from which several kinds of volcanic products were erupted. A few cover thousands of square miles, have volumes of tens of cubic miles, and apparently are related to a large-scale basinal collapse structure and associated calderas. Most ash-flow tuffs are rhyolite or dacite; a few are peralkaline soda rhyolite. Older ash-flow tuffs are commonly diagenetically altered to a variety of secondary minerals; of the younger tuffs, only those that erupted into shallow lakes exhibit comparable alteration. Close