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• 91. [Article] Geology of the Tillamook Head--Necanicum Junction area, Clatsop County, northwest Oregon

  Five distinct lithologic units compose the Tertiary rocks in the Tillamook Head - Necanicum Junction area of the northern Oregon Coast Range. They are: the late Eocene to early Miocene Oswald West mudstones, ...

  Citation × Citation Citation Abstract Copy Title: Geology of the Tillamook Head--Necanicum Junction area, Clatsop County, northwest Oregon Author: Neel, Robert Holmes Five distinct lithologic units compose the Tertiary rocks in the Tillamook Head - Necanicum Junction area of the northern Oregon Coast Range. They are: the late Eocene to early Miocene Oswald West mudstones, the middle Miocene Angora Peak sandstone and Silver Point mudstone members of the Astoria Formation, and the middle Miocene intrusive and extrusive Depoe Bay and Cape Foulweather basalts. These units are locally overlain by Pleistocene marine terraces and Holocene beach and dune sands, stream alluvium, and landslide deposits. The Oswald West mudstones, Angora Peak sandstones, and Silver Point mudstones are informal stratigraphic names used in this study. The Oswald West mudstones consist of over 2, 000 feet of well-bedded, intensely burrowed, silty mudstones and siltstones interstratified with minor glauconitic sandstones, tuff beds, and thick bedded tuffaceous siltstones Foraminifera, trace fossils, glauconite, and the general fine-grained character of these rocks suggest that deposition occurred in an open marine deep-water environment, possibly as part of a prodelta or on the outer continental shelf. The Angora Peak member is composed of several hundred feet of moderately sorted, medium- to coarse-grained quartzose-feldspathic and lithic sandstones. The sandstones unconformably overlie the Oswald West mudstones and are thick bedded, laminated, and less commonly cross-laminated. Sedimentary structures, sorting, and stratigraphic relationships suggest that the sandstones were deposited in a high energy, wave-dominated environment, possibly as delta sheet sands. The sands were, in part, redistributed by waves and longshore drift to form offshore coastal barrier bars and.linear clastic shoreline deposits. The overlying 650-foot thick Silver Point member consists dominantly of dark gray, micaceous, laminated mudstones and very thin siltstones. Rhythmically interbedded mudstones and fine-grained turbidite sandstones occur in the lower part of the unit. Deposition occurred in cool, low energy, open marine conditions, probably of sublittoral to upper bathyal depths. Oversteepening of Angora Peak sheet sands on the delta front may have resulted in periodic slumping of sands which were transported by turbidity currents into a shelf basin of the deeper water Silver Point delta-slope environment. An east to west paleocurrent pattern in the Salver Point turbidite sandstonesis consistent with this model. Sandstone petrography and heavy mineral suites of the Astoria Formation suggests a dominantly volcanic and sedimentary provenance for these strata, probably the pre-Miocene volcanic rocks of the western Cascades and local Coast Range Eocene basalts and sandstones. Mineralogy and rare rock fragments in the sandstones also suggest that some detritus was derived from the granitic, metamorphic, and Paleozoic sedimentary terrains of eastern Oregon and Washington, and from British Columbia and western Idaho, possibly transported via an "ancestral Columbia River drainage system. Numerous dikes, sills, and irregular-shaped plutons of Depoe Bay Basalt and Cape Foulweather Basalt intruded the Oswald West mudstones and Astoria Formation. The major intrusive body in the area is the 900-foot thick sill that forms Tillamook Head. At Ecola State Park, the forceful intrusion of this sill into the semi-consolidated Silver Point strata at very shallow depths produced local synsedimentary folds. Over 1, 000 feet of extrusive Depoe Bay Basalt palagonitized pillow lavas and breccias and 2.00 feet of very local Cape Foulweather pillow lavas lie with angular unconformity over the Silver Point member. Deformation which accompanied the general Coast Range uplift during the late Miocene to Pleistocene formed four northeast-trending folds in the thesis area and two sets of high angle faults which strike north-south and northwest- southeast through the area. In addition, active landslides are abundant throughout the area, particularly along the coast. Economic resources of the area include basalt quarry rock for rip-rap and road base, basalt stream gravels for road aggregate, and potential petroleum resources may occur in the adjacent offshore area. Title: Geology of the Tillamook Head--Necanicum Junction area, Clatsop County, northwest Oregon Author: Neel, Robert Holmes Five distinct lithologic units compose the Tertiary rocks in the Tillamook Head - Necanicum Junction area of the northern Oregon Coast Range. They are: the late Eocene to early Miocene Oswald West mudstones, the middle Miocene Angora Peak sandstone and Silver Point mudstone members of the Astoria Formation, and the middle Miocene intrusive and extrusive Depoe Bay and Cape Foulweather basalts. These units are locally overlain by Pleistocene marine terraces and Holocene beach and dune sands, stream alluvium, and landslide deposits. The Oswald West mudstones, Angora Peak sandstones, and Silver Point mudstones are informal stratigraphic names used in this study. The Oswald West mudstones consist of over 2, 000 feet of well-bedded, intensely burrowed, silty mudstones and siltstones interstratified with minor glauconitic sandstones, tuff beds, and thick bedded tuffaceous siltstones Foraminifera, trace fossils, glauconite, and the general fine-grained character of these rocks suggest that deposition occurred in an open marine deep-water environment, possibly as part of a prodelta or on the outer continental shelf. The Angora Peak member is composed of several hundred feet of moderately sorted, medium- to coarse-grained quartzose-feldspathic and lithic sandstones. The sandstones unconformably overlie the Oswald West mudstones and are thick bedded, laminated, and less commonly cross-laminated. Sedimentary structures, sorting, and stratigraphic relationships suggest that the sandstones were deposited in a high energy, wave-dominated environment, possibly as delta sheet sands. The sands were, in part, redistributed by waves and longshore drift to form offshore coastal barrier bars and.linear clastic shoreline deposits. The overlying 650-foot thick Silver Point member consists dominantly of dark gray, micaceous, laminated mudstones and very thin siltstones. Rhythmically interbedded mudstones and fine-grained turbidite sandstones occur in the lower part of the unit. Deposition occurred in cool, low energy, open marine conditions, probably of sublittoral to upper bathyal depths. Oversteepening of Angora Peak sheet sands on the delta front may have resulted in periodic slumping of sands which were transported by turbidity currents into a shelf basin of the deeper water Silver Point delta-slope environment. An east to west paleocurrent pattern in the Salver Point turbidite sandstonesis consistent with this model. Sandstone petrography and heavy mineral suites of the Astoria Formation suggests a dominantly volcanic and sedimentary provenance for these strata, probably the pre-Miocene volcanic rocks of the western Cascades and local Coast Range Eocene basalts and sandstones. Mineralogy and rare rock fragments in the sandstones also suggest that some detritus was derived from the granitic, metamorphic, and Paleozoic sedimentary terrains of eastern Oregon and Washington, and from British Columbia and western Idaho, possibly transported via an "ancestral Columbia River drainage system. Numerous dikes, sills, and irregular-shaped plutons of Depoe Bay Basalt and Cape Foulweather Basalt intruded the Oswald West mudstones and Astoria Formation. The major intrusive body in the area is the 900-foot thick sill that forms Tillamook Head. At Ecola State Park, the forceful intrusion of this sill into the semi-consolidated Silver Point strata at very shallow depths produced local synsedimentary folds. Over 1, 000 feet of extrusive Depoe Bay Basalt palagonitized pillow lavas and breccias and 2.00 feet of very local Cape Foulweather pillow lavas lie with angular unconformity over the Silver Point member. Deformation which accompanied the general Coast Range uplift during the late Miocene to Pleistocene formed four northeast-trending folds in the thesis area and two sets of high angle faults which strike north-south and northwest- southeast through the area. In addition, active landslides are abundant throughout the area, particularly along the coast. Economic resources of the area include basalt quarry rock for rip-rap and road base, basalt stream gravels for road aggregate, and potential petroleum resources may occur in the adjacent offshore area. Close

• 92. [Article] Prevalence and distribution of calicivirus neutralizing antibody in selected U.S. cattle

  Serum samples from 1,046 Kansas cattle were examined for the presence of neutralizing antibody to caliciviruses known to be circulating in the marine environment. All sera were from farm-origin cattle, ...

  Citation × Citation Citation Abstract Copy Title: Prevalence and distribution of calicivirus neutralizing antibody in selected U.S. cattle Author: Boyt, Peter M. Serum samples from 1,046 Kansas cattle were examined for the presence of neutralizing antibody to caliciviruses known to be circulating in the marine environment. All sera were from farm-origin cattle, with the number tested being proportionate to the total number of cattle in each county. These sera were selected in a random manner from blood samples routinely submitted to the Kansas State/Federal Brucellosis Laboratory in 1988. The majority of animals represented by the sample were adult females of mixed breed. The sera were tested for the presence of antibody to the San Miguel sea lion virus (SMSV) types; 1, 5, 7,.8, 14, and the Tillamook calicivirus serotype (BCV Bos-1). Antibody was detected by the microneutralization procedure with Vero cells as the indicator system. Using a 1:10 serum dilution, neutralizing antibodies were found in the sample to all serotypes except SMSV-1 with prevalence rates ranging from .3% to 32%. All neutralization screen tests were read to,a 100% end point (EP) using a 100-421 tissue culture infective dose 50% end point (TCID50) of challenge virus. Due to the low antibody levels, prevalence values were found to be very dependent upon the virus challenge dose and the antibody EP used in the test. Antibody titers to four serotypes ranged from 1:10 to 1:1280 with most falling in the 1:10 to 1:20 range using a 50% antibody EP and a 100-421 TCID5O of challenge virus. Several sera were found to possess neutralizing antibody to multiple serotypes. Antibody to SMSV-5 was shown to be well distributed throughout Kansas indicating that widespread exposure to this marine calicivirus had occurred. Title: Prevalence and distribution of calicivirus neutralizing antibody in selected U.S. cattle Author: Boyt, Peter M. Serum samples from 1,046 Kansas cattle were examined for the presence of neutralizing antibody to caliciviruses known to be circulating in the marine environment. All sera were from farm-origin cattle, with the number tested being proportionate to the total number of cattle in each county. These sera were selected in a random manner from blood samples routinely submitted to the Kansas State/Federal Brucellosis Laboratory in 1988. The majority of animals represented by the sample were adult females of mixed breed. The sera were tested for the presence of antibody to the San Miguel sea lion virus (SMSV) types; 1, 5, 7,.8, 14, and the Tillamook calicivirus serotype (BCV Bos-1). Antibody was detected by the microneutralization procedure with Vero cells as the indicator system. Using a 1:10 serum dilution, neutralizing antibodies were found in the sample to all serotypes except SMSV-1 with prevalence rates ranging from .3% to 32%. All neutralization screen tests were read to,a 100% end point (EP) using a 100-421 tissue culture infective dose 50% end point (TCID50) of challenge virus. Due to the low antibody levels, prevalence values were found to be very dependent upon the virus challenge dose and the antibody EP used in the test. Antibody titers to four serotypes ranged from 1:10 to 1:1280 with most falling in the 1:10 to 1:20 range using a 50% antibody EP and a 100-421 TCID5O of challenge virus. Several sera were found to possess neutralizing antibody to multiple serotypes. Antibody to SMSV-5 was shown to be well distributed throughout Kansas indicating that widespread exposure to this marine calicivirus had occurred. Close

• 93. [Article] Stratigraphy and sedimentation of the Onion Peak area, Clatsop County, Oregon

  Six Tertiary units are exposed in the Onion Peak area near the town of Cannon Beach., Oregon. The units consist of: late Eocene to early Miocene Oswald West mudstones (informal), middle Miocene Astoria ...

  Citation × Citation Citation Abstract Copy Title: Stratigraphy and sedimentation of the Onion Peak area, Clatsop County, Oregon Author: Smith, Thomas N. Six Tertiary units are exposed in the Onion Peak area near the town of Cannon Beach., Oregon. The units consist of: late Eocene to early Miocene Oswald West mudstones (informal), middle Miocene Astoria Formation (Angora Peak sandstone and Silver Point mudstone members.-informal), middle Miocene basalts of intrusive and extrusive Depoe Bay Basalt, and intrusive Cape Foulweather Basalt. Beach sands, Pleistocene marine terraces, and stream alluvium unconformably overlie these Tertiary units. The Oswald West mudstones consist of more than 1600 feet of well-bedded, burrowed, tuffaceou siltstones and mudstones with sub ordinate tuff and glauconitic sandstone beds. Foraminiferal and trace fossil evidence suggest that these mudstones were deposited in marine waters of upper bathyal depths. The overlying 1700-foot thick Astoria Formation is divided into two informal mappable members: the 1100-foot thick Angora Peak sandstone and the 600-foot thick Silver Point mudstone (proposed informally in this study). The Angora Peak sandstone member is composed of several hundred feet of thickly laminated feldspathic sandstones with local cross-bedded lithic conglomerates and carbonaceous siltstones. The overlying Silver Point mudstone member consists of rhythmically interbedded mudstones and graded turbidite sandstones, overlain by bedded mudstones, thin siltstones, and local conglomerate lenses. Conglomerate clast lithologies and heavy mineral suites of the Silver Point and Angora. Peak members are similar to the sediment carried by the Columbia River today and may be an ancient deposit of that river system. The provenances for these strata were pre-Miocene andesitic and dacitic rocks of the western Cascades, the Coast Range Eocene Tillamook basalts, and plutonic, metamorphic, and sedimentary contributions from eastern Oregon and Washington, Idaho, Montana, and Canada, Channel fluvial sandstones, conglomerates, and well-bedded shallow marine sandstones of the Angora Peak member, probably interfingering with interbedded, deeper marine (600 feet-outer shelf) mudstones and turbidite sndstones of the Silver Point member, are interpreted to have been deposited near the mouth of a river, adjacent to the ocean as a delta. Dikes, sills, peperites, and irregular intrusive bodies of middle Miocene Depoe Bay Basalt intruded Oswald West mudstones and the Astoria Formation. These aphanitic to finely crystalline equigranular basaltic intrusives locally fed over 2000 feet of palagonitized pillow lavas and basaltic breccias which now form the highest peaks in the area. The intrusives locally penecontemporaneously deformed the Astoria strata into a series of large-scale soft sediment deformation folds and sedimentary breccias. Cape Foulweather Basalt intrudes all sedimentary units and cuts the Depoe Bay Basalts. The basalt is recognized by sparse, large plagioclase phenocrysts. The area is cut by several east-west and north-south trending high angle faults with up to 500 feet displacement A large north-south syncline in the central part of the thesis area delineates a structural and depositional basin. A smaller north-plunging anticline is present near the coast. Recent landslides in the Silver Point member have been particularly destructive along the coast and inland; they have been caused by wave, stream action, and by man over-steepening unstable slopes. Crushed basalt quarry rock and potential petroleum reservoirs in the Angora Peak sandstones in stratigraphic and structural tra traps, particularly in nearby offshore areas, are the main geological economic resources of the area. Title: Stratigraphy and sedimentation of the Onion Peak area, Clatsop County, Oregon Author: Smith, Thomas N. Six Tertiary units are exposed in the Onion Peak area near the town of Cannon Beach., Oregon. The units consist of: late Eocene to early Miocene Oswald West mudstones (informal), middle Miocene Astoria Formation (Angora Peak sandstone and Silver Point mudstone members.-informal), middle Miocene basalts of intrusive and extrusive Depoe Bay Basalt, and intrusive Cape Foulweather Basalt. Beach sands, Pleistocene marine terraces, and stream alluvium unconformably overlie these Tertiary units. The Oswald West mudstones consist of more than 1600 feet of well-bedded, burrowed, tuffaceou siltstones and mudstones with sub ordinate tuff and glauconitic sandstone beds. Foraminiferal and trace fossil evidence suggest that these mudstones were deposited in marine waters of upper bathyal depths. The overlying 1700-foot thick Astoria Formation is divided into two informal mappable members: the 1100-foot thick Angora Peak sandstone and the 600-foot thick Silver Point mudstone (proposed informally in this study). The Angora Peak sandstone member is composed of several hundred feet of thickly laminated feldspathic sandstones with local cross-bedded lithic conglomerates and carbonaceous siltstones. The overlying Silver Point mudstone member consists of rhythmically interbedded mudstones and graded turbidite sandstones, overlain by bedded mudstones, thin siltstones, and local conglomerate lenses. Conglomerate clast lithologies and heavy mineral suites of the Silver Point and Angora. Peak members are similar to the sediment carried by the Columbia River today and may be an ancient deposit of that river system. The provenances for these strata were pre-Miocene andesitic and dacitic rocks of the western Cascades, the Coast Range Eocene Tillamook basalts, and plutonic, metamorphic, and sedimentary contributions from eastern Oregon and Washington, Idaho, Montana, and Canada, Channel fluvial sandstones, conglomerates, and well-bedded shallow marine sandstones of the Angora Peak member, probably interfingering with interbedded, deeper marine (600 feet-outer shelf) mudstones and turbidite sndstones of the Silver Point member, are interpreted to have been deposited near the mouth of a river, adjacent to the ocean as a delta. Dikes, sills, peperites, and irregular intrusive bodies of middle Miocene Depoe Bay Basalt intruded Oswald West mudstones and the Astoria Formation. These aphanitic to finely crystalline equigranular basaltic intrusives locally fed over 2000 feet of palagonitized pillow lavas and basaltic breccias which now form the highest peaks in the area. The intrusives locally penecontemporaneously deformed the Astoria strata into a series of large-scale soft sediment deformation folds and sedimentary breccias. Cape Foulweather Basalt intrudes all sedimentary units and cuts the Depoe Bay Basalts. The basalt is recognized by sparse, large plagioclase phenocrysts. The area is cut by several east-west and north-south trending high angle faults with up to 500 feet displacement A large north-south syncline in the central part of the thesis area delineates a structural and depositional basin. A smaller north-plunging anticline is present near the coast. Recent landslides in the Silver Point member have been particularly destructive along the coast and inland; they have been caused by wave, stream action, and by man over-steepening unstable slopes. Crushed basalt quarry rock and potential petroleum reservoirs in the Angora Peak sandstones in stratigraphic and structural tra traps, particularly in nearby offshore areas, are the main geological economic resources of the area. Close

• 94. [Article] A model for rating agricultural suitability of land parcels in western Oregon

  A model was developed that allows potential users to identify the agricultural suitability of parcels of land in western Oregon. Literature was reviewed regarding five possible benefits to be derived from ...

  Citation × Citation Citation Abstract Copy Title: A model for rating agricultural suitability of land parcels in western Oregon Author: Rogers, William Reinhold A model was developed that allows potential users to identify the agricultural suitability of parcels of land in western Oregon. Literature was reviewed regarding five possible benefits to be derived from public policies designed to preserve productive agricultural land. They are (1) the provision of sufficient cropland to supply the food needs of an expanding national and world population; (2) the maintenance of healthy local economies in predominantly agricultural areas; (3) the increased efficiency that results from more orderly urban development; (4) the reduction of resource misallocations resulting fromthe conversion of the better agricultural lands to other uses; (5) the provision of open space in rapidly urbanizing areas. Systems currently being used to identify productive agricultural land were also reviewed. Among these were the land capability classification system, the "prime" and "unique" farmlands criteria, and various numerical indices such as the corn suitability rating. A comprehensive compilation was made of all factors having potentially significant effects on agricultural land use. Similar factors were grouped together and a model was developed incorporating the most important of these factors. Specific criteria were developed for evaluating the effects of the factors. The workability of the model was determined by applying it in several test areas and through numerous consultations. The model itself was developed in the form of a branching flow chart. After an initial question regarding commitment to other uses has been answered, the procedure involves the determination of two separate scores, one for soil productivity that ranges from 0-52 points and one for compatibility that ranges from 0- 48 points. The overall rating of agricultural suitability ranges from 0-100 points and is obtained by adding the two separate scores. Information needed to calculate the two scores is readily available. The determination of the soil productivity score requires use of crop yield data as well as irrigation and drainage information for soil map units. The determination of the compatibility score requires information about surrounding land uses and the location of the nearest urban growth boundary. To validate the model 43 parcels of land in six counties in western Oregon (Benton, Clackamas, Jackson, Lane, Marion and Tillamook) were selected as representative of six predetermined situations regarding soil productivity and extent of urban growth pressure. These situations were: (1) highly productive soils with little growth pressure; (2) highly productive soils with heavy growth pressure; (3) moderately productive soils with little growth pressure; (4) moderately productive soils with heavy growth pressure; (5) soils with relatively low productivity and little growth pressure; (6) soils with relatively low productivity and heavy growth pressure. The t test using pooled variances (Sp²) was used to determine whether differences between the means of the six situations were significant. The resulting analysis showed that when applying the model, those parcels with highly productive soils and little growth pressure had significantly higher total scores than all other parcels. Likewise, the parcels with soils of relatively low productivity and heavy growth pressure had the lowest scores. The other parcels fell somewhere in between. The model has several potential applications in Oregon. It can be used as a tool in evaluating the effects of changes in agricultural management, in evaluating the effects of land use decisions on surrounding agricultural lands, or in evaluating proposals for lot splits. It could also be used as part of the general long-range planning process. Other applications may be discovered by potential users as the need arises. Title: A model for rating agricultural suitability of land parcels in western Oregon Author: Rogers, William Reinhold A model was developed that allows potential users to identify the agricultural suitability of parcels of land in western Oregon. Literature was reviewed regarding five possible benefits to be derived from public policies designed to preserve productive agricultural land. They are (1) the provision of sufficient cropland to supply the food needs of an expanding national and world population; (2) the maintenance of healthy local economies in predominantly agricultural areas; (3) the increased efficiency that results from more orderly urban development; (4) the reduction of resource misallocations resulting fromthe conversion of the better agricultural lands to other uses; (5) the provision of open space in rapidly urbanizing areas. Systems currently being used to identify productive agricultural land were also reviewed. Among these were the land capability classification system, the "prime" and "unique" farmlands criteria, and various numerical indices such as the corn suitability rating. A comprehensive compilation was made of all factors having potentially significant effects on agricultural land use. Similar factors were grouped together and a model was developed incorporating the most important of these factors. Specific criteria were developed for evaluating the effects of the factors. The workability of the model was determined by applying it in several test areas and through numerous consultations. The model itself was developed in the form of a branching flow chart. After an initial question regarding commitment to other uses has been answered, the procedure involves the determination of two separate scores, one for soil productivity that ranges from 0-52 points and one for compatibility that ranges from 0- 48 points. The overall rating of agricultural suitability ranges from 0-100 points and is obtained by adding the two separate scores. Information needed to calculate the two scores is readily available. The determination of the soil productivity score requires use of crop yield data as well as irrigation and drainage information for soil map units. The determination of the compatibility score requires information about surrounding land uses and the location of the nearest urban growth boundary. To validate the model 43 parcels of land in six counties in western Oregon (Benton, Clackamas, Jackson, Lane, Marion and Tillamook) were selected as representative of six predetermined situations regarding soil productivity and extent of urban growth pressure. These situations were: (1) highly productive soils with little growth pressure; (2) highly productive soils with heavy growth pressure; (3) moderately productive soils with little growth pressure; (4) moderately productive soils with heavy growth pressure; (5) soils with relatively low productivity and little growth pressure; (6) soils with relatively low productivity and heavy growth pressure. The t test using pooled variances (Sp²) was used to determine whether differences between the means of the six situations were significant. The resulting analysis showed that when applying the model, those parcels with highly productive soils and little growth pressure had significantly higher total scores than all other parcels. Likewise, the parcels with soils of relatively low productivity and heavy growth pressure had the lowest scores. The other parcels fell somewhere in between. The model has several potential applications in Oregon. It can be used as a tool in evaluating the effects of changes in agricultural management, in evaluating the effects of land use decisions on surrounding agricultural lands, or in evaluating proposals for lot splits. It could also be used as part of the general long-range planning process. Other applications may be discovered by potential users as the need arises. Close