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• 81. [Article] A Characterization of Lake Abert Tufa Mounds Lake Abert, Oregon

  A series of tufa mounds is found within the northern basin of Lake Abert, located within southeastern Oregon. The mounds have been divided into 3 main groups and 1 sub-group (A1, A2, B, and C) based upon ...

  Citation × Citation Citation Abstract Copy Title: A Characterization of Lake Abert Tufa Mounds Lake Abert, Oregon Author: Bartruff, Anthony Lynn Year: 2013 A series of tufa mounds is found within the northern basin of Lake Abert, located within southeastern Oregon. The mounds have been divided into 3 main groups and 1 sub-group (A1, A2, B, and C) based upon spatial and textural considerations. Mound groups appear at two different elevations: the 1310 meter elevation (Groups A2, B, and C), and the 1318 meter elevation (Group A1). Published carbon age dating of the Lake Abert 1325 meter strandline and the 1310 meter strandline indicates that the mounds were formed during the Late Pleistocene/Early Holocene. Facies analysis and mineralogical analysis of the mounds indicates that the mounds were primarily formed subaqueously during a lake regression, supporting oxygen isotope data from previous researchers. Magnetometer data within Groups A1 and A2 suggests that the mounds are associated with a series of magnetic lows which are oriented in joint sets (NW-SE, and N-S) which match the orientation of faulting within the region. While there appears to be another early mound building episode, no direct evidence confirms this. Title: A Characterization of Lake Abert Tufa Mounds Lake Abert, Oregon Author: Bartruff, Anthony Lynn Year: 2013 A series of tufa mounds is found within the northern basin of Lake Abert, located within southeastern Oregon. The mounds have been divided into 3 main groups and 1 sub-group (A1, A2, B, and C) based upon spatial and textural considerations. Mound groups appear at two different elevations: the 1310 meter elevation (Groups A2, B, and C), and the 1318 meter elevation (Group A1). Published carbon age dating of the Lake Abert 1325 meter strandline and the 1310 meter strandline indicates that the mounds were formed during the Late Pleistocene/Early Holocene. Facies analysis and mineralogical analysis of the mounds indicates that the mounds were primarily formed subaqueously during a lake regression, supporting oxygen isotope data from previous researchers. Magnetometer data within Groups A1 and A2 suggests that the mounds are associated with a series of magnetic lows which are oriented in joint sets (NW-SE, and N-S) which match the orientation of faulting within the region. While there appears to be another early mound building episode, no direct evidence confirms this. Close

• 82. [Article] The structural controls of the Vale Rhinehart Buttes complex, Vale KGRA, Malheur County, Oregon

  The Vale KGRA is characterized by high heat flow, two to five times higher than the worldwide average, and by numerous hot springs. The hot springs are aligned along faults. This phenomena is typical of ...

  Citation × Citation Citation Abstract Copy Title: The structural controls of the Vale Rhinehart Buttes complex, Vale KGRA, Malheur County, Oregon Author: Doerr, John Timothy Year: 1986 The Vale KGRA is characterized by high heat flow, two to five times higher than the worldwide average, and by numerous hot springs. The hot springs are aligned along faults. This phenomena is typical of a Basin and Range type geothermal system. The hot geothermal fluids migrate upward along the more permeable, fault planes. The rocks exposed in the Vale area are the Pliocene Chalk Butte formation and the Pleistocene beds of Captain Keeney Pass. Both units are composed of volcaniclastic siltstones, sandstones and conglomerates. The units are differentiated by color, texture and degree of lithification. About 200 meters of the Chalk Butte formation and 100 meters of the beds of Captain Keeney Pass are exposed in the area. Silicification is wide spread in the rocks of the Chalk Butte formation. Title: The structural controls of the Vale Rhinehart Buttes complex, Vale KGRA, Malheur County, Oregon Author: Doerr, John Timothy Year: 1986 The Vale KGRA is characterized by high heat flow, two to five times higher than the worldwide average, and by numerous hot springs. The hot springs are aligned along faults. This phenomena is typical of a Basin and Range type geothermal system. The hot geothermal fluids migrate upward along the more permeable, fault planes. The rocks exposed in the Vale area are the Pliocene Chalk Butte formation and the Pleistocene beds of Captain Keeney Pass. Both units are composed of volcaniclastic siltstones, sandstones and conglomerates. The units are differentiated by color, texture and degree of lithification. About 200 meters of the Chalk Butte formation and 100 meters of the beds of Captain Keeney Pass are exposed in the area. Silicification is wide spread in the rocks of the Chalk Butte formation. Close

• 83. [Article] Ecological Change on California’s Channel Islands from the Pleistocene to the Anthropocene

  To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by Oxford University ...

  Citation × Citation Citation Abstract Copy Title: Ecological Change on California’s Channel Islands from the Pleistocene to the Anthropocene Author: Ghalambor, Cameron K., Still, Christopher, Rick, Torben C., et al., Sillett, T. Scott To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by Oxford University Press on behalf of the American Institute of Biological Sciences and is in the public domain. The published article can be found at: http://bioscience.oxfordjournals.org/. Title: Ecological Change on California’s Channel Islands from the Pleistocene to the Anthropocene Author: Ghalambor, Cameron K., Still, Christopher, Rick, Torben C., et al., Sillett, T. Scott To the best of our knowledge, one or more authors of this paper were federal employees when contributing to this work. This is the publisher’s final pdf. The article was published by Oxford University Press on behalf of the American Institute of Biological Sciences and is in the public domain. The published article can be found at: http://bioscience.oxfordjournals.org/. Close

• 84. [Article] Paleointensity of the Earth's magnetic field and K-Ar dating of the Louchadiere volcanic flow (Central France) : new evidence for the Laschamp excursion

  copyrighted by American Geophysical Union.

  Citation × Citation Citation Abstract Copy Title: Paleointensity of the Earth's magnetic field and K-Ar dating of the Louchadiere volcanic flow (Central France) : new evidence for the Laschamp excursion Author: Chauvin, Annick, Duncan, Robert A., Bonhommet, Norbert, Levi, Saul copyrighted by American Geophysical Union. Title: Paleointensity of the Earth's magnetic field and K-Ar dating of the Louchadiere volcanic flow (Central France) : new evidence for the Laschamp excursion Author: Chauvin, Annick, Duncan, Robert A., Bonhommet, Norbert, Levi, Saul copyrighted by American Geophysical Union. Close

• 85. [Article] Seismoturbidite record as preserved at core sites at the Cascadia and Sumatra–Andaman subduction zones

  This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: http://publications.copernicus.org/home.html.

  Citation × Citation Citation Abstract Copy Title: Seismoturbidite record as preserved at core sites at the Cascadia and Sumatra–Andaman subduction zones Author: Patton, J. R., Udrekh, Goldfinger, C., Djadjadihardja, Y., Morey, A. E., Romsos, C., Black, B. This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: http://publications.copernicus.org/home.html. Title: Seismoturbidite record as preserved at core sites at the Cascadia and Sumatra–Andaman subduction zones Author: Patton, J. R., Udrekh, Goldfinger, C., Djadjadihardja, Y., Morey, A. E., Romsos, C., Black, B. This is the publisher’s final pdf. The published article is copyrighted by Copernicus Publications and can be found at: http://publications.copernicus.org/home.html. Close

• 86. [Article] Export production and carbonate dissolution in the central equatorial Pacific Ocean over the past 1 Myr

  Copyright 2000 by the American Geophysical Union

  Citation × Citation Citation Abstract Copy Title: Export production and carbonate dissolution in the central equatorial Pacific Ocean over the past 1 Myr Author: Polsky, C. H., Leinen, M., Murray, R. W., Knowlton, C. W., Mix, Alan C. Copyright 2000 by the American Geophysical Union Title: Export production and carbonate dissolution in the central equatorial Pacific Ocean over the past 1 Myr Author: Polsky, C. H., Leinen, M., Murray, R. W., Knowlton, C. W., Mix, Alan C. Copyright 2000 by the American Geophysical Union Close

• 87. [Article] Volcanoes of the Three Sisters region, Oregon Cascades

  Gerald W. Williams Collection

  Citation × Citation Citation Abstract Copy Title: Volcanoes of the Three Sisters region, Oregon Cascades Author: Williams, Howel, 1898-1980 Gerald W. Williams Collection Title: Volcanoes of the Three Sisters region, Oregon Cascades Author: Williams, Howel, 1898-1980 Gerald W. Williams Collection Close

• 88. [Article] Virola dominicana sp. nov., (Myristicaceae) from Dominican amber

  This is an author's manuscript version. The published article is copyrighted by NRC Research Press and can be found at: http://www.nrcresearchpress.com/doi/full/10.1139/cjb-2013-0019.

  Citation × Citation Citation Abstract Copy Title: Virola dominicana sp. nov., (Myristicaceae) from Dominican amber Author: Poinar, George, Jr., Steeves, Royce This is an author's manuscript version. The published article is copyrighted by NRC Research Press and can be found at: http://www.nrcresearchpress.com/doi/full/10.1139/cjb-2013-0019. Title: Virola dominicana sp. nov., (Myristicaceae) from Dominican amber Author: Poinar, George, Jr., Steeves, Royce This is an author's manuscript version. The published article is copyrighted by NRC Research Press and can be found at: http://www.nrcresearchpress.com/doi/full/10.1139/cjb-2013-0019. Close

• 89. [Article] Origin and distribution of the fish fauna of the Harney Basin, Oregon

  A theory of the origin and distribution of fishes in the Harney Basin is presented. Blitzen River, the hydrographically and ecologically isolated creeks, and the upland tributaries of Silvies River all ...

  Citation × Citation Citation Abstract Copy Title: Origin and distribution of the fish fauna of the Harney Basin, Oregon Author: Bisson, Peter Andre A theory of the origin and distribution of fishes in the Harney Basin is presented. Blitzen River, the hydrographically and ecologically isolated creeks, and the upland tributaries of Silvies River all contain populations derived from the basin's Pleistocene connection with Malheur River of the Snake system. Colonization of many streams took Place during periods of high precipitation; isolation has resulted froth dessicating trends since the last glaciation. Stream capture has apparently facilitated a secondary invasion of fishes into Silvies River from John Day River, a tributary of the lower Columbia. This conclusion is further supported by the presence of several species only in central Silvies River within the basin. Certain populations similar to those occurring in isolated regions of the Harney Basin also exist above the barrier falls of the south fork of John Day River, but this drainage is believed to be another disrupted fragment containing descendants of a more ancient Columbia fauna. Speculation regarding the sequence of radiation of different species throughout the Columbia watershed is aided by distributional patterns and knowledge of hydrographic history. Title: Origin and distribution of the fish fauna of the Harney Basin, Oregon Author: Bisson, Peter Andre A theory of the origin and distribution of fishes in the Harney Basin is presented. Blitzen River, the hydrographically and ecologically isolated creeks, and the upland tributaries of Silvies River all contain populations derived from the basin's Pleistocene connection with Malheur River of the Snake system. Colonization of many streams took Place during periods of high precipitation; isolation has resulted froth dessicating trends since the last glaciation. Stream capture has apparently facilitated a secondary invasion of fishes into Silvies River from John Day River, a tributary of the lower Columbia. This conclusion is further supported by the presence of several species only in central Silvies River within the basin. Certain populations similar to those occurring in isolated regions of the Harney Basin also exist above the barrier falls of the south fork of John Day River, but this drainage is believed to be another disrupted fragment containing descendants of a more ancient Columbia fauna. Speculation regarding the sequence of radiation of different species throughout the Columbia watershed is aided by distributional patterns and knowledge of hydrographic history. Close

• 90. [Article] Structure and stratigraphy of the Sheep Mountain area, Centennial Range, Montana-Idaho

  The thesis area includes 44 square miles of the Centennial Range in Beaverhead County, Montana, and Clark County, Idaho. The rocks exposed in the area range in age from Precambrian to Recent and have been ...

  Citation × Citation Citation Abstract Copy Title: Structure and stratigraphy of the Sheep Mountain area, Centennial Range, Montana-Idaho Author: Moran, John Lee The thesis area includes 44 square miles of the Centennial Range in Beaverhead County, Montana, and Clark County, Idaho. The rocks exposed in the area range in age from Precambrian to Recent and have been divided into 23 mapped units. Pre-Belt metamorphic basement rocks are overlain unconformably by 3,433 feet of Paleozoic strata included in eleven formations. These formations represent all of the periods of the Paleozoic except the Ordovician and Silurian. Nine formations represent all the periods of the Mesozoic and total approximately 3,127 feet in thickness. Cenozoic units present in the area are basalts and rhyolites, landslide debris, glacial deposits, and alluvium. The major structure of the thesis area is a fault block that is the result of uplifting and tilting of the east-west trending Centennial Range during the downwarp of the Snake River Plain in late Pliocene and Pleistocene time. No stratigraphic or structural conditions in the thesis area are favorable for the accumulation and entrapment of oil and gas. Phosphorite has been mined from the Phosphoria Formation in the area. Title: Structure and stratigraphy of the Sheep Mountain area, Centennial Range, Montana-Idaho Author: Moran, John Lee The thesis area includes 44 square miles of the Centennial Range in Beaverhead County, Montana, and Clark County, Idaho. The rocks exposed in the area range in age from Precambrian to Recent and have been divided into 23 mapped units. Pre-Belt metamorphic basement rocks are overlain unconformably by 3,433 feet of Paleozoic strata included in eleven formations. These formations represent all of the periods of the Paleozoic except the Ordovician and Silurian. Nine formations represent all the periods of the Mesozoic and total approximately 3,127 feet in thickness. Cenozoic units present in the area are basalts and rhyolites, landslide debris, glacial deposits, and alluvium. The major structure of the thesis area is a fault block that is the result of uplifting and tilting of the east-west trending Centennial Range during the downwarp of the Snake River Plain in late Pliocene and Pleistocene time. No stratigraphic or structural conditions in the thesis area are favorable for the accumulation and entrapment of oil and gas. Phosphorite has been mined from the Phosphoria Formation in the area. Close

• 91. [Article] Calcium carbonate, organic carbon, and quartz in hemipelagic sediments off Oregon : a preliminary investigation

  An analysis of the amounts of calcium carbonate, organic carbon, quartz, and the rates of sediment accumulation in hemipelagic sediments off Oregon has revealed that the accumulation rates of the total sediment, ...

  Citation × Citation Citation Abstract Copy Title: Calcium carbonate, organic carbon, and quartz in hemipelagic sediments off Oregon : a preliminary investigation Author: Peterson, Robert E. An analysis of the amounts of calcium carbonate, organic carbon, quartz, and the rates of sediment accumulation in hemipelagic sediments off Oregon has revealed that the accumulation rates of the total sediment, organic carbon, and quartz were at least twice as high in the late Pleistocene as they were during the Holocene. The accumulation rate of calcium carbonate was at least 8 times as high. There may have been a short transition period at the end of the last glacial stage from about 14,000 to 12,500 years B.P. when the sedimentation rate was very high up to 75 cm/l000 years. There is evidence that the amount of organic carbon in deep-sea sediments is a function of terrigenous influx, of preservation, and possibly of depth of burial in the sediment. Turbidite sequences in the deep-sea environment off Oregon contain much higher amounts of organic carbon in the upper fine-grained portion of the sequence than in the coarser basal sediment of the sequence, indicating that organic carbon is concentrated in the finer and slower settling parts of the flow. In lower continental slope sediments, the greatest amounts of organic carbon are found in the <4 micron size fraction. Title: Calcium carbonate, organic carbon, and quartz in hemipelagic sediments off Oregon : a preliminary investigation Author: Peterson, Robert E. An analysis of the amounts of calcium carbonate, organic carbon, quartz, and the rates of sediment accumulation in hemipelagic sediments off Oregon has revealed that the accumulation rates of the total sediment, organic carbon, and quartz were at least twice as high in the late Pleistocene as they were during the Holocene. The accumulation rate of calcium carbonate was at least 8 times as high. There may have been a short transition period at the end of the last glacial stage from about 14,000 to 12,500 years B.P. when the sedimentation rate was very high up to 75 cm/l000 years. There is evidence that the amount of organic carbon in deep-sea sediments is a function of terrigenous influx, of preservation, and possibly of depth of burial in the sediment. Turbidite sequences in the deep-sea environment off Oregon contain much higher amounts of organic carbon in the upper fine-grained portion of the sequence than in the coarser basal sediment of the sequence, indicating that organic carbon is concentrated in the finer and slower settling parts of the flow. In lower continental slope sediments, the greatest amounts of organic carbon are found in the <4 micron size fraction. Close

• 92. [Article] Interrelationships of spodosols, andepts, and ultisols on coastal terraces in Curry County, Oregon

  Distribution and characteristics of soils were determined across a series of six coastal terraces in Curry Co., Oregon. Classification of soils and interrelationships of properties were determined. Soil-landscape ...

  Citation × Citation Citation Abstract Copy Title: Interrelationships of spodosols, andepts, and ultisols on coastal terraces in Curry County, Oregon Author: Hoppe, Diane A. S. Distribution and characteristics of soils were determined across a series of six coastal terraces in Curry Co., Oregon. Classification of soils and interrelationships of properties were determined. Soil-landscape relationships were examined and soil profile development related to relative ages of terraces. Ten pedons were sampled from five terraces of Pleistocene age. All profiles were analyzed for particle size distribution; bulk density; water retention, -1.5 MPa; aluminum and iron extracted with oxalate, citrate-dithionite and sodium pyrophosphate; pH; phosphate retention; exchangeable aluminum; organic carbon; and cation exchange capacity. Andeptic Humitropepts occur on intermediate terraces, in close proximity to the coast. Andeptic Haplohumults occur on the better drained areas of the intermediate terrace, but further inland. Soils in less well drained areas of the intermediate and higher terraces classify as Spodosols, based on morphological features. Ultisols occur on the highest terraces. Profile morphology, particle size and iron extracts are compared between terraces to derive age relationships. Title: Interrelationships of spodosols, andepts, and ultisols on coastal terraces in Curry County, Oregon Author: Hoppe, Diane A. S. Distribution and characteristics of soils were determined across a series of six coastal terraces in Curry Co., Oregon. Classification of soils and interrelationships of properties were determined. Soil-landscape relationships were examined and soil profile development related to relative ages of terraces. Ten pedons were sampled from five terraces of Pleistocene age. All profiles were analyzed for particle size distribution; bulk density; water retention, -1.5 MPa; aluminum and iron extracted with oxalate, citrate-dithionite and sodium pyrophosphate; pH; phosphate retention; exchangeable aluminum; organic carbon; and cation exchange capacity. Andeptic Humitropepts occur on intermediate terraces, in close proximity to the coast. Andeptic Haplohumults occur on the better drained areas of the intermediate terrace, but further inland. Soils in less well drained areas of the intermediate and higher terraces classify as Spodosols, based on morphological features. Ultisols occur on the highest terraces. Profile morphology, particle size and iron extracts are compared between terraces to derive age relationships. Close

• 93. [Article] Stratigraphic Record of Pliocene-Pleistocene Basin Evolution and Deformation Along the San Andreas Fault, Mecca Hills, California

  Sedimentary rocks in the Mecca Hills record a 3-4 Myr history of basin evolution and deformation within the southern San Andreas fault (SAF) zone. Detailed geologic mapping, measured sections, lithofacies ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphic Record of Pliocene-Pleistocene Basin Evolution and Deformation Along the San Andreas Fault, Mecca Hills, California Author: McNabb, James Year: 2014 Sedimentary rocks in the Mecca Hills record a 3-4 Myr history of basin evolution and deformation within the southern San Andreas fault (SAF) zone. Detailed geologic mapping, measured sections, lithofacies analysis, and preliminary paleomagnetic data indicate that sedimentation and deformation in the Mecca Hills resulted from evolution of local fault zone complexities superimposed on regional subsidence and uplift. Sediment was derived from sources northeast of the SAF and transported southeast along the fault zone in large rivers, alluvial fans, and a smaller fault-bounded lake. Inversion of the Painted Canyon fault from oblique SW-side down to SW-side up slip was the main control on local deposition and deformation. Regional controls are suggested by an angular unconformity observed in the Mecca and Indio Hills along ~50 km of the SAF and synchronous post-740 ka uplift northeast of the SAF along ~80 km of the fault zone. Title: Stratigraphic Record of Pliocene-Pleistocene Basin Evolution and Deformation Along the San Andreas Fault, Mecca Hills, California Author: McNabb, James Year: 2014 Sedimentary rocks in the Mecca Hills record a 3-4 Myr history of basin evolution and deformation within the southern San Andreas fault (SAF) zone. Detailed geologic mapping, measured sections, lithofacies analysis, and preliminary paleomagnetic data indicate that sedimentation and deformation in the Mecca Hills resulted from evolution of local fault zone complexities superimposed on regional subsidence and uplift. Sediment was derived from sources northeast of the SAF and transported southeast along the fault zone in large rivers, alluvial fans, and a smaller fault-bounded lake. Inversion of the Painted Canyon fault from oblique SW-side down to SW-side up slip was the main control on local deposition and deformation. Regional controls are suggested by an angular unconformity observed in the Mecca and Indio Hills along ~50 km of the SAF and synchronous post-740 ka uplift northeast of the SAF along ~80 km of the fault zone. Close

• 94. [Article] Geology and structure of the Brothers Fault Zone in the central part of the Millican SE quadrangle, Deschutes County, Oregon

  The thesis is a structural and petrographic study of approximately 23 square miles in the Millican SE quadrangle, Deschutes County, Oregon. The area lies along the Brothers fault zone. Bedrock in the area ...

  Citation × Citation Citation Abstract Copy Title: Geology and structure of the Brothers Fault Zone in the central part of the Millican SE quadrangle, Deschutes County, Oregon Author: Tucker, Elizabeth Ruth The thesis is a structural and petrographic study of approximately 23 square miles in the Millican SE quadrangle, Deschutes County, Oregon. The area lies along the Brothers fault zone. Bedrock in the area is of Pliocene to Recent age and consists of an older basaltic unit with an associated dacite, a younger dacite, and a younger basaltic unit. The older basaltic unit and both dacites have been severely faulted. The younger basaltic unit has filled in topographic lows and is relatively undeformed. The dominant faults in the area are en echelon high-angle normal faults trending N. 40°W. with vertical displacements up to 600 feet. Cross faults with smaller displacements trend N. 45°E. The normal faults are Reidel and conjugate Reidel shears and are interpreted as the surface expression of a deep-seated right lateral displacement. The fault zone displaces units of Miocene to Pleistocene age and is considered to have been active during that time. Title: Geology and structure of the Brothers Fault Zone in the central part of the Millican SE quadrangle, Deschutes County, Oregon Author: Tucker, Elizabeth Ruth The thesis is a structural and petrographic study of approximately 23 square miles in the Millican SE quadrangle, Deschutes County, Oregon. The area lies along the Brothers fault zone. Bedrock in the area is of Pliocene to Recent age and consists of an older basaltic unit with an associated dacite, a younger dacite, and a younger basaltic unit. The older basaltic unit and both dacites have been severely faulted. The younger basaltic unit has filled in topographic lows and is relatively undeformed. The dominant faults in the area are en echelon high-angle normal faults trending N. 40°W. with vertical displacements up to 600 feet. Cross faults with smaller displacements trend N. 45°E. The normal faults are Reidel and conjugate Reidel shears and are interpreted as the surface expression of a deep-seated right lateral displacement. The fault zone displaces units of Miocene to Pleistocene age and is considered to have been active during that time. Close

• 95. [Article] Morphometric properties of nivation hollows on Hart Mountain, Lake County, Oregon

  Hart Mountain is a basaltic fault block mountain in the semi-desert region of the northern Basin and Range province in south-central Oregon. Geomorphic processes associated with lingering snowpatches have ...

  Citation × Citation Citation Abstract Copy Title: Morphometric properties of nivation hollows on Hart Mountain, Lake County, Oregon Author: Rademacher, Christopher L. Hart Mountain is a basaltic fault block mountain in the semi-desert region of the northern Basin and Range province in south-central Oregon. Geomorphic processes associated with lingering snowpatches have formed nivation hollows, which are small scale depressions in the hillsides. The lingering snow in the hollows prohibits shrub growth. Bedrock scarps, present in some of the hollows, show indications of chemical alteration. Bills are present below most of the hollows, indicating that surface runoff from these sites occurs. Average hillslope, which controls the shear stress placed on soil particles, is statistically related to morphometric attributes defining the size and angles of the hollows. Simple linear regressions and the nonparametric Kendall's rank correlation coefficient (p-) and Theil's C test for the regression line slope suggest that average hillslope is directly related to the morphometric attributes of the hollows. Heat transfer controls the areal distribution and duration of snowpatcnes. A relative insolation factor and elevation are taken as surrogates for heat transfer. These surrogates are likewise correlated with the morphometric attributes of the hollows. Both the elevation and the relative insolation factor suggest an inverse relationship between heat transfer and the size of nivation hollows. The hollows on Hart Mountain appear to have been formed by accelerated nivation processes during the Pleistocene and are currently being modified by less intense nivation. Title: Morphometric properties of nivation hollows on Hart Mountain, Lake County, Oregon Author: Rademacher, Christopher L. Hart Mountain is a basaltic fault block mountain in the semi-desert region of the northern Basin and Range province in south-central Oregon. Geomorphic processes associated with lingering snowpatches have formed nivation hollows, which are small scale depressions in the hillsides. The lingering snow in the hollows prohibits shrub growth. Bedrock scarps, present in some of the hollows, show indications of chemical alteration. Bills are present below most of the hollows, indicating that surface runoff from these sites occurs. Average hillslope, which controls the shear stress placed on soil particles, is statistically related to morphometric attributes defining the size and angles of the hollows. Simple linear regressions and the nonparametric Kendall's rank correlation coefficient (p-) and Theil's C test for the regression line slope suggest that average hillslope is directly related to the morphometric attributes of the hollows. Heat transfer controls the areal distribution and duration of snowpatcnes. A relative insolation factor and elevation are taken as surrogates for heat transfer. These surrogates are likewise correlated with the morphometric attributes of the hollows. Both the elevation and the relative insolation factor suggest an inverse relationship between heat transfer and the size of nivation hollows. The hollows on Hart Mountain appear to have been formed by accelerated nivation processes during the Pleistocene and are currently being modified by less intense nivation. Close

• 96. [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

• 97. [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

• 98. [Article] Late Pleistocene and recent archaeology and geomorphology of the south shore of Harney Lake, Oregon

  The present study was a response to the discovery of two artifacts found in a ditch wall near Harney Lake, Oregon. These were lying on a buried lake floor that appeared to be of late Pleistocene or early ...

  Citation × Citation Citation Abstract Copy Title: Late Pleistocene and recent archaeology and geomorphology of the south shore of Harney Lake, Oregon Author: Gehr, Keith Donald Year: 1980 The present study was a response to the discovery of two artifacts found in a ditch wall near Harney Lake, Oregon. These were lying on a buried lake floor that appeared to be of late Pleistocene or early Recent age. Other sediments exposed in the ditch seemed to relate to at least some of the phases of the pluvial lake sequence in the Harney Basin. Three problems were considered: (1) the geomorphology and dating of the pluvial lake stillstands, (2) whether the original artifacts were part of a larger early site, and (3) whether there was any relationship between archaeological sites and geomorphic features in the area. These problems were approached in the field by stratigraphic mapping of exposed sediments and by an archaeological survey of a defined study area. Test excavations were made adjacent to the location of the original artifact discovery to search for other cultural material. Beachline records of four stillstands of Pluvial Lake Malheur are preserved in the exposed sediments. The youngest beachline is undated. Three others were 14C dated from associated fossil molluscs at 32,000, 9620 and 8680 B.P. At least in the case of the 8680 B.P. lake, the Harney Basin was filled to overflowing and was a part of the Columbia River system. The Voltage basalt flow, which dammed the outlet of the Basin in Malheur Gap, was in place by 32,000 years ago. There is no evidence for a diversion of the Basin outlet to Crane Gap following this event. Molluscan fossils and diatoms were used, along with soil texture analyses, to help identify and differentiate sedimentary deposits and to draw environmental inferences. Artifacts were found both on and beneath buried beach deposits of the 8680 B.P. lake. Four of the five sites in the study area were either on wave-cut terraces or other lakeshore features associated with this lake. Diagnostic artifacts are Lind Coulee points, crescents, basally ground leaf-shaped points, and what are apparently true blades. The sites seem to have been located to take advantage of shallow water littoral zone resources. Fish may have been an important dietary item of the early Harney Basin dwellers. Large salmonid vertebrae from fish in the 10 kg weight class are found on the playa. By using the relationship between landforms and elevations it may be possible to predict the general age class of other sites on the margin of the playas. Title: Late Pleistocene and recent archaeology and geomorphology of the south shore of Harney Lake, Oregon Author: Gehr, Keith Donald Year: 1980 The present study was a response to the discovery of two artifacts found in a ditch wall near Harney Lake, Oregon. These were lying on a buried lake floor that appeared to be of late Pleistocene or early Recent age. Other sediments exposed in the ditch seemed to relate to at least some of the phases of the pluvial lake sequence in the Harney Basin. Three problems were considered: (1) the geomorphology and dating of the pluvial lake stillstands, (2) whether the original artifacts were part of a larger early site, and (3) whether there was any relationship between archaeological sites and geomorphic features in the area. These problems were approached in the field by stratigraphic mapping of exposed sediments and by an archaeological survey of a defined study area. Test excavations were made adjacent to the location of the original artifact discovery to search for other cultural material. Beachline records of four stillstands of Pluvial Lake Malheur are preserved in the exposed sediments. The youngest beachline is undated. Three others were 14C dated from associated fossil molluscs at 32,000, 9620 and 8680 B.P. At least in the case of the 8680 B.P. lake, the Harney Basin was filled to overflowing and was a part of the Columbia River system. The Voltage basalt flow, which dammed the outlet of the Basin in Malheur Gap, was in place by 32,000 years ago. There is no evidence for a diversion of the Basin outlet to Crane Gap following this event. Molluscan fossils and diatoms were used, along with soil texture analyses, to help identify and differentiate sedimentary deposits and to draw environmental inferences. Artifacts were found both on and beneath buried beach deposits of the 8680 B.P. lake. Four of the five sites in the study area were either on wave-cut terraces or other lakeshore features associated with this lake. Diagnostic artifacts are Lind Coulee points, crescents, basally ground leaf-shaped points, and what are apparently true blades. The sites seem to have been located to take advantage of shallow water littoral zone resources. Fish may have been an important dietary item of the early Harney Basin dwellers. Large salmonid vertebrae from fish in the 10 kg weight class are found on the playa. By using the relationship between landforms and elevations it may be possible to predict the general age class of other sites on the margin of the playas. Close

• 99. [Article] Organic matter compositions and loadings in soils and sediments along the Fly River, Papua New Guinea

  This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/geochimica-et-co...

  Citation × Citation Citation Abstract Copy Title: Organic matter compositions and loadings in soils and sediments along the Fly River, Papua New Guinea Author: Merrell, David, Goni, Miguel A., Kurtz, Andrew, Alleau, Yvan, Moore, Eric, Portier, Evan This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/geochimica-et-cosmochimica-acta/ Title: Organic matter compositions and loadings in soils and sediments along the Fly River, Papua New Guinea Author: Merrell, David, Goni, Miguel A., Kurtz, Andrew, Alleau, Yvan, Moore, Eric, Portier, Evan This is an author's peer-reviewed final manuscript, as accepted by the publisher. The published article is copyrighted by Elsevier and can be found at: http://www.journals.elsevier.com/geochimica-et-cosmochimica-acta/ Close

• 100. [Article] Continuous seismic profiling investigation of the southern Oregon continental shelf between Cape Blanco and Coos Bay

  A structure map was constructed of the continental shelf between Cape Blanco and Coos Bay, Oregon, exclusively from an interpretation of approximately 700 km of continuous seismic profiles. At least ten ...

  Citation × Citation Citation Abstract Copy Title: Continuous seismic profiling investigation of the southern Oregon continental shelf between Cape Blanco and Coos Bay Author: Mackay, Angus James A structure map was constructed of the continental shelf between Cape Blanco and Coos Bay, Oregon, exclusively from an interpretation of approximately 700 km of continuous seismic profiles. At least ten discernible seismic units were mapped on the bases of acoustic appearance, lateral continuity, angular unconformities, and faults. The offshore units tentatively were correlated with onshore geology and are believed to range in age from the latest Jurassic to late Pleistocene. The sparker profiles reveal that the continental shelf off southern Oregon has experienced significant late Tertiary and Quaternary accretion due to deposition and tectonic uplift. The oldest rock exposures, believed to be the latest Jurassic in age, crop out on the inner continental shelf on the topographic highs off Cape Blanco and Coquille Point. Erosional remnants of probable Late Cretaceous turbidites and the middle Eocene sandstone beds also are exposed on the bathymetric high on the inner shelf southwest of Cape Arago. The initial emplacement of these three uplifted structural blocks is probably a result of late Eocene wrench faulting of the Port Orford shear zone and of the postulated shear zone at Coquille Point. No other early Tertiary sediments apparently are exposed on this portion of the Oregon continental shelf, but they probably extend seaward at depth on the continental margin. Middle Tertiary strata are believed to be exposed on the outer shelf topographic high southwest of Cape Arago. Sediments of Miocene to Pliocene age were deposited throughout much of the continental shelf that was surveyed. The greatest amount of deposition occurred in a north-south trending basin between Cape Blanco and Coquille Bank. Late to post-Pliocene tectonism uplifted and exposed the older underlying rocks on the inner shelf, which are probably of uppermost Jurassic to middle Tertiary age. These same stresses also deformed the Mio-Pliocene sediments into gently undulating structures on the inner shelf. The greatest deformation occurred on the outer shelf and formed Coquille Bank, a north-south trending, doubly plunging, asymmetrical anticline. The terraces or benches on the upper continental slope to the north and south of the Bank are structural features resulting from the doubly plunging anticline. Eustatic sea level lowerings during the Pleistocene truncated the shelf structures as deep as 130 m below present sea level. The detritus was deposited as a wedge of sediments, which forms an unconformable contact with the underlying strata on the outer shelf and upper slope between Coos Bay and Coquille Bank. In areas of deposition there is no distinct break between the shelf and the upper slope; the former merely merges into the latter in a continuous convex curve. In areas of nondeposition, the edge of the shelf is an erosional and structural feature. A possible buried channel was detected northwest of the mouth of the Coquille River. This sediment filled channel is believed to be an erosional remnant of a former course of the Coquille River during a lower stand of sea level. Title: Continuous seismic profiling investigation of the southern Oregon continental shelf between Cape Blanco and Coos Bay Author: Mackay, Angus James A structure map was constructed of the continental shelf between Cape Blanco and Coos Bay, Oregon, exclusively from an interpretation of approximately 700 km of continuous seismic profiles. At least ten discernible seismic units were mapped on the bases of acoustic appearance, lateral continuity, angular unconformities, and faults. The offshore units tentatively were correlated with onshore geology and are believed to range in age from the latest Jurassic to late Pleistocene. The sparker profiles reveal that the continental shelf off southern Oregon has experienced significant late Tertiary and Quaternary accretion due to deposition and tectonic uplift. The oldest rock exposures, believed to be the latest Jurassic in age, crop out on the inner continental shelf on the topographic highs off Cape Blanco and Coquille Point. Erosional remnants of probable Late Cretaceous turbidites and the middle Eocene sandstone beds also are exposed on the bathymetric high on the inner shelf southwest of Cape Arago. The initial emplacement of these three uplifted structural blocks is probably a result of late Eocene wrench faulting of the Port Orford shear zone and of the postulated shear zone at Coquille Point. No other early Tertiary sediments apparently are exposed on this portion of the Oregon continental shelf, but they probably extend seaward at depth on the continental margin. Middle Tertiary strata are believed to be exposed on the outer shelf topographic high southwest of Cape Arago. Sediments of Miocene to Pliocene age were deposited throughout much of the continental shelf that was surveyed. The greatest amount of deposition occurred in a north-south trending basin between Cape Blanco and Coquille Bank. Late to post-Pliocene tectonism uplifted and exposed the older underlying rocks on the inner shelf, which are probably of uppermost Jurassic to middle Tertiary age. These same stresses also deformed the Mio-Pliocene sediments into gently undulating structures on the inner shelf. The greatest deformation occurred on the outer shelf and formed Coquille Bank, a north-south trending, doubly plunging, asymmetrical anticline. The terraces or benches on the upper continental slope to the north and south of the Bank are structural features resulting from the doubly plunging anticline. Eustatic sea level lowerings during the Pleistocene truncated the shelf structures as deep as 130 m below present sea level. The detritus was deposited as a wedge of sediments, which forms an unconformable contact with the underlying strata on the outer shelf and upper slope between Coos Bay and Coquille Bank. In areas of deposition there is no distinct break between the shelf and the upper slope; the former merely merges into the latter in a continuous convex curve. In areas of nondeposition, the edge of the shelf is an erosional and structural feature. A possible buried channel was detected northwest of the mouth of the Coquille River. This sediment filled channel is believed to be an erosional remnant of a former course of the Coquille River during a lower stand of sea level. Close