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- <p>Geochemistry -- Missouri<br />Geology -- Missouri<br />Ore deposits<br />Cobalt<br />Nickel</p> (1)
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Articles 1 - 30 of 41
Full-Text Articles in Physical Sciences and Mathematics
An Analysis Of Nitrate Concentrations In The Ground-Water Of Antwerp Township, Van Buren County, Michigan, John Emil Klanke
An Analysis Of Nitrate Concentrations In The Ground-Water Of Antwerp Township, Van Buren County, Michigan, John Emil Klanke
Masters Theses
Private wells were tested for nitrate during the spring of 1979 throughout sections of Antwerp Township, Van Buren County, southwestern Michigan (sections 1-5, 7-22, 24-26, 28-31, 33-36). Water samples were collected from 159 private wells and analyzed for nitrate. Nitrate concentrations ranged from less than 1 mg/1 NO3-N to 14.6 mg/1 NO3-N. Seven wells were found to have nitrate concentrations equaling or exceeding the National Interim Primary Drinking Water Standard of 10 mg/1 NO3-N. Nitrate concentrations were related to age of septic system, well depth below static water level, land use, and soil type. …
Structural Analysis Of Precambrian Metasedimentary Rocks Of The Swede Gulch Formation, Nahant, South Dakota, Richard G. Cookman
Structural Analysis Of Precambrian Metasedimentary Rocks Of The Swede Gulch Formation, Nahant, South Dakota, Richard G. Cookman
Masters Theses
Precambrian X tectonites deformed between thermal domes in the northern Black Hills 1.7 B.Y.B.P. display variably trending isoclinal folds cross-cut by southeast trending slip-folds developed in discrete shear zones. Eugeosynclinal sedimentary rocks consisting of shale, quartzarenite , sublitharenite, and graywacke were metamorphosed to phyllite, quartzite, and metagraywacke during two syntectonic phases and one post-tectonic phase. The earliest syntectonic metamorphism was associated with development of isoclinal folds and may have produced amphibolite or greenschist facies. It was succeeded by retrograde metamorphism of greenschist facies syntectonic with and post-tectonic to development of southeast trending folds.
Mica, chlorite, iron oxides, and graphite are …
Petrology Of Fluvial And Shoreline Sands In A Modern Arc-Trench Gap, Guatemala, James Robert Bartel
Petrology Of Fluvial And Shoreline Sands In A Modern Arc-Trench Gap, Guatemala, James Robert Bartel
Masters Theses
Petrographic studies of modern sands, derived from areas with known source rocks, climate, relief, environments of deposition, and tectonic setting, are essential for compiling compositional models for ancient sandstones. The Pacific coastal plain of Guatemala is terminated 25-60 km inland by the steep slopes of a row of active Quaternary volcanic and granitic rocks.
Sands being deposited on the coastal plain by the Rio Nahulate, which drains the older volcanic and granitic terrane, show significant compositional differences with those supplied by the Rio Samala, which drains an area dominated by active volcanism: Q9F35L56 vs. Q …
Selected Shallow Electrical Resistivity Surveys At Volcano Cliffs, Bernalillo County, And Warm Springs, Sandoval County, New Mexico, Sidney S. Brandwein
Selected Shallow Electrical Resistivity Surveys At Volcano Cliffs, Bernalillo County, And Warm Springs, Sandoval County, New Mexico, Sidney S. Brandwein
Earth and Planetary Sciences ETDs
To help assess the applicability of shallow electrical resistivity measurements in New Mexico, two diverse areas in northwestern New Mexico were chosen as electrical resistivity survey sites: Volcano Cliffs and Warm Springs.
Volcano Cliffs, 15 km northwest of Albuquerque, is an area of Pleistocene volcanic activity which manifested itself in cinder cones and basalt flows. At Volcano Cliffs five different electrode configurations were employed to test the horizontality and derive the thicknesses and resistivities of the three geoelectric units present. All electrode configurations yielded reliable results. The ambiguities presented by the principle of equivalence were successfully treated. The first geoelectric …
Dolomitization Of The Brassfield Formation (Lower Silurian) In Adams County, Ohio, Lisa L. Varga
Dolomitization Of The Brassfield Formation (Lower Silurian) In Adams County, Ohio, Lisa L. Varga
Masters Theses
The Lower Silurian Brassfield Formation which outcrops in the Tri-state area of Ohio, Indiana and Kentucky is a transgressive sequence consisting of a series of interbedded shales, limestones and dolostones. Evidence from depositional environments, petrography and spatial relationships of dolomitized and undolomitized rock suggests dolomitization in southwestern Ohio was a two-stage process. Initial dolomitization was restricted to the basal Belfast Member and probably occurred penecontemporaneously on small supratidal islands in a manner analagous to that which occurs in the modern sabkha environment of the Persian Gulf. Regional dolomitization was a later diagenetic event related to the formation of a fresh-seawater …
The Petrology And Geochemistry Of Keweenawan Diabase Dikes In Ontonagon, Gogebic, Iron And Dickinson Counties, Michigan, James J. Hahnenberg
The Petrology And Geochemistry Of Keweenawan Diabase Dikes In Ontonagon, Gogebic, Iron And Dickinson Counties, Michigan, James J. Hahnenberg
Masters Theses
Petrographic and chemical studies of Keeweenawan-age diabase dikes in Michigan's Upper Peninsula show two major groupings, Porcupine Mountain dikes and Lower Keweenawan dikes consist of two major rock types, fine-grained smaller dikes and the coarse-grained central portions of larger dikes. Major minerals are subophitic plagioclase and pyroxene. The rocks, as compared to the "average" basalts, are low in Al203, high in Ti02, K20, P205 and contain moderate amounts of Fe0t. They are classified as quartz tholeiites. Several parental magma sources that would account for these and other …
Mineralogy And Petrology Of Lava Flows (Tertiary-Quaternary) In Southeastern Idaho And At Black Mountain, Rich County, Utah, Barbara J. Puchy
Mineralogy And Petrology Of Lava Flows (Tertiary-Quaternary) In Southeastern Idaho And At Black Mountain, Rich County, Utah, Barbara J. Puchy
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Lava flows of Tertiary-Quaternary age occur in Enoch Valley, Upper Valley, and Slug Valley in southeastern Idaho. The basalts in Upper Valley and Enoch Valley contain olivine (Fo69 to Fo37), plagioclase (An62 to An39), augite and Fe-Ti oxides. The lava in Slug Valley lacks plagioclase, but contains sanidine (Or70 to Or56) with a trace of biotite and amphibole, and thus, has been termed alkali trachyte.
Black Mountain, on the eastern side of Bear Lake, northeastern Utah, is capped by basalt. Minerals present include olivine (Fo83 to Fo72), plagioclase …
Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek
Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Blacksmith Formation of Middle Cambrian (Albertan) age was studied in southeastern Idaho and northernmost Utah. Lithology and sedimentary structures were compared with modern environments and ancient rocks to determine environments of deposition, paleo-geography, diagenetic alterations and patterns of dolomitization.
The Blacksmith Formation can be divided into five basic rock types. Rock type A has cryptalgalaminae, mudcracks, and lacks bioturbation. Rock type A is inferred to have been deposited in the upper intertidal to supratidal environment. Rock type B is extremely dolomitized and brecciated. It is inferred that rock type B was deposited in the upper intertidal to supratidal environment. …
Growth-Form Analysis And Paleoecology Of The Corals Of The Late Ordovician Through Mid-Silurian Fish Haven And Laketown Formations, Bear River Range, North-Central Utah, Thomas B. Rich
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Morphology of corals of the Late Ordovician through mid-Silurian Fish Haven and Laketown Formations were analyzed to document adaptations to inferred enviromental conditions, i.e., (bathymetry, illumination, sedimentation, currents, and energy), under which their enclosing sediment was deposited. Specimens and data were collected from six sites. Insoluble-residue tests were performed on the corals' matrices.
Individual corallites of radial-lensoidal corals radiate in all directions. Vertical growth, however, was restricted in turbulent conditions. Umbrellic, radial-lensoidal corals feature downward facing corallites, considered to be an adaptation to a well illuminated environment.
On tabular lensoidal corals, constituent corallites faces exclusively upward, an orientation needed under …
Petrology Of The Arumbera Sandstone, Late Proterozoic(?) - Early Cambrian, Northeastern Amadeus Basin, Central Australia, Keith T. Conrad
Petrology Of The Arumbera Sandstone, Late Proterozoic(?) - Early Cambrian, Northeastern Amadeus Basin, Central Australia, Keith T. Conrad
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Arumbera Sandstone forms distinctive strike ridges with dark reddish slopes and orange-white cliffs throughout most of the northeastern Amadeus Basin. It is divisible into four readily mappable informal units. The ridge-forming units, 2 and 4, are divided into three and two subunits, respectively.
Unit 1, Subunit 2b, Unit 3 and Subunit 4b are generally comprised of recessive, pale-red to grayish-red, medium- to thin-bedded, fineto medium-grained arkose with major proportions of siltstone and mudshale. These sedimentary bodies are interpreted as a complex system of coastal to nearshore-marine environments including tidal flats, tidal channels, estuaries and beaches. Evidence includes: (1) predominance …
Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines
Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Community succession, the orderly changes a community experiences with time, is considered to be the result of either autogenic or allogenic factors working singularly or in combination. It has been further suggested that, as communities undergo succession, certain biological parameters change in a predictable manner. Examination of members 2 through 4 of the Mississippian (Kinderhook-Osage) Lodgepole Formation of Samaria Mountain, Idaho provides a means to evaluate these concepts.
Within the study section comprised of 125 beds (61.5 m thick), four rock types are recognized. These include: (1) fossiliferous wackestone (78% of beds), which ranges in color from dark-gray (N3) to …
Provenance And Description Of Landslide Masses, Rainbow Gardens, Clark County, Nevada, Joseph R. Parolini
Provenance And Description Of Landslide Masses, Rainbow Gardens, Clark County, Nevada, Joseph R. Parolini
UNLV Theses, Dissertations, Professional Papers, and Capstones
A landslide breccia of plutonic and metamorphic rocks located 20 km east of Las Vegas, Nevada is interstratified with the late Tertiary Thumb Formation. Rock types of similar mineral composition to the landslide masses in the Rainbow Gardens are found 60 km to the east in the Gold Butte (Nevada) area. The landslide masses were displaced into their present position by lateral strike-slip motion along either the left-lateral Lake Mead fault system or the right-lateral Las Vegas shear zone. In the Rainbow Gardens landslide masses, five plutonic rock types, including Rapakivi granite, match rocks from the Gold Butte area, both …
Provenance And Description Of Landslide Masses, Rainbow Gardens Clark County, Nevada., Joseph R. Parolini
Provenance And Description Of Landslide Masses, Rainbow Gardens Clark County, Nevada., Joseph R. Parolini
UNLV Theses, Dissertations, Professional Papers, and Capstones
A landslide breccia of plutonic and metamorphic rocks located 20 km east of Las Vegas, Nevada is interstratified with the late Tertiary Thumb Formation. Rock types of similar mineral composition to the landslide masses in the Rainbow Gardens are found 60 km to the east in the Gold Butte (Nevada) area. The landslide masses were displaced into their present position by lateral strike-slip motion along either the left-lateral Lake Mead fault system or the right-lateral Las Vegas shear zone. In t.he Rainbow Gardens landslide masses, five plutonic rock types, including rapakivi granite, match rocks from the Gold Butte area, both …
U-Pb Systematics And Ages Of Rocks From The Zone Of Cataclasis, Bitterroot Dome, Southwestern Montana, Edward Charles Arruda
U-Pb Systematics And Ages Of Rocks From The Zone Of Cataclasis, Bitterroot Dome, Southwestern Montana, Edward Charles Arruda
Masters Theses
The eastern flank of the Bitterroot range, western Montana, consists of a 100 km-long zone of cataclasis which dips to the east. Zircons in sheared granitic plutons from three localities within this zone were dated using U-Pb methods. These zircons, which consist of anhedral cores and euhedral overgrowths, yield concordia lower-intercept ages of 48-52 million years before the present, dates which likely represent crystallization ages of the plutons. Shearing which affected these plutons, therefore, is significantly younger than the 72-76 million year age assigned for eastward movement of the Sapphire tectonic block whose detachment zone has been interpreted as the …
Geology Of The Plutonic And Hypabyssal Rocks Of The Betts Cove Ophiolite Complex, Newfoundland, Bruce D. Idleman
Geology Of The Plutonic And Hypabyssal Rocks Of The Betts Cove Ophiolite Complex, Newfoundland, Bruce D. Idleman
Geology Theses and Dissertations
The Betts Cove ophiolite complex lies within the Dunnage Zone island arc terrain of central Newfoundland. It forms the base of the lower Ordovician Snooks Arm Group, which consists of mafic igneous rocks of the ophiolite and a thick sequence of volcanic and volcaniclastic rocks which conformably overlies it. The Snooks Arm Group is unconformably overlain by sub-aerial sediments and volcanics of the presumed Silurian Cape St. John Group.
The base o£ the ophiolite complex consists predominantly of ultramafic rocks. These are interlayered on a variety of scales, and show mesoscopic igneous structures which suggest that they were produced by …
Permo-Triassic Reconstruction Of Western Pangea And The Evolution Of The Gulf Of Mexico-Caribbean Region, James Lawrence Pindell
Permo-Triassic Reconstruction Of Western Pangea And The Evolution Of The Gulf Of Mexico-Caribbean Region, James Lawrence Pindell
Geology Theses and Dissertations
A Permo-Triassic reconstruction of western Pangea (North America, South America, Africa) is proposed that is characterized by: 1) definition of the North Atlantic fit by matching of marginal offsets (fracture zones) along the opposing margins, 2) a South Atlantic fit that is tighter than the Bullard fit and that is achieved by treating Africa as two plates astride the Benue Trough and related structures during the Cretaceous, 3) complete closure of the Proto-Atlantic Ocean between North and South America, accomplished by placing the Yucatan block between the Ouachita Mountains and Venezuela, 4) a proposed Hercynian suture zone that separates zones …
Some Chemical And Mineralogical Aspects Of Plutonic Rocks From The North Arm Mountain Massif, Bay Of Islands Ophiolite, Newfoundland, Jerry W. Sullivan
Some Chemical And Mineralogical Aspects Of Plutonic Rocks From The North Arm Mountain Massif, Bay Of Islands Ophiolite, Newfoundland, Jerry W. Sullivan
Geology Theses and Dissertations
Whole-rock major and trace element compositions of one basalt, one diabase, and 21 rocks from the magmatic-plutonic units of the North Arm Mountain massif, Bay of Islands ophiolite, Newfoundland, were determined. Mineral compositions of a subset of the plutonic rocks were also determined.
The major and trace element compositions of the basalt and diabase are similar to abyssal tholeiites, and this is consistent with the REE data of Malpas (1978) and Suen, et. al. (1979) that suggest the lavas and dikes formed from a depleted or slightly enriched abyssal tholeiitic magma. The alkaline nature of the magma proposed by several …
Geologic Investigations In The Cayman Trough And The Nature Of The Plutonic Foundation Of The Oceanic Crust, Janet B. Stroup
Geologic Investigations In The Cayman Trough And The Nature Of The Plutonic Foundation Of The Oceanic Crust, Janet B. Stroup
Geology Theses and Dissertations
A survey of the literature that deals with the gabbroic rocks believed to comprise the foundation of the oceanic crust indicates that the overwhelming majority of these rocks are recovered from escarpments associated with transform faults. The wide range of mineral and chemical compositions characterizing oceanic gabbroic rocks suggests that the lower oceanic crust is much more heterogeneous in nature than was previously suggested by the results of geophysical investigations. The examination of gabbroic rocks recovered in situ from the walls of the Mid-Cayman Rise rift valley by the submersible ALVIN not only supports the notion that oceanic gabbroic rocks …
Structural Studies Of The Ordovician Flysch And Melange In Albany County, New York, Frederick W. Vollmer
Structural Studies Of The Ordovician Flysch And Melange In Albany County, New York, Frederick W. Vollmer
Geology Theses and Dissertations
The middle Ordovician rocks of the Albany 15 minute quadrangle comprise interbedded graywacke and shale, and in the east, coarse cobble or olistostromic deposits. The detrital composition, westward fining and regional westward transgression of these deposits indicate that these were sediments shed off the westward thrusting Taconic Allochthon. Primary sedimentary structures show that these rocks were deposited by turbidity currents flowing into a longitudinal trough, probably formed in response to increased load during overthrusting. Although strongly dependent on lithology, deformation intensity generally increases from west to east; from essentially undeformed bedded flysch through asymmetrically folded and thrust beds to highly …
Structural Analysis Of An Area Near Middlebury, Vermont, Paul A. Washington
Structural Analysis Of An Area Near Middlebury, Vermont, Paul A. Washington
Geology Theses and Dissertations
Detailed mapping of an area near Middlebury, Vermont, reveals a multiple deformational scheme quite different from that previously proposed. The published stratigraphy of the middle Ordovician limestones, on which earlier structural theories are based; was found to be inaccurate, so a new system has been defined. An unreported early generation of cleavage has been discovered which indicates the existence of a decollement zone in the upper Bascom formation. The second generation of cleavage and its associated folding were well defined by earlier workers, but this study shows that it is also a thin-skinned event.
The last deformation, as exhibited by …
Stratigraphy, Lithofacies And Depositional Environment Of The Cowlitz Formation, T. 4 And 5n., R. 5w. Northwest Oregon, Dale M. Timmons
Stratigraphy, Lithofacies And Depositional Environment Of The Cowlitz Formation, T. 4 And 5n., R. 5w. Northwest Oregon, Dale M. Timmons
Dissertations and Theses
The Cowlitz Formation in southern Columbia and Clatsop counties, northwest Oregon was studied in order to prepare a geologic map of parts of this formation and to determine the character of its lithofacies and the environments of deposition.
The Structure, Geologic Evolution And Regional Significance Of The Bethel Creek-North Fork Area, Coos And Curry Counties, Oregon, Carl Fredrick Gullixson
The Structure, Geologic Evolution And Regional Significance Of The Bethel Creek-North Fork Area, Coos And Curry Counties, Oregon, Carl Fredrick Gullixson
Dissertations and Theses
The original purpose of this study was a detailed structural analysis of the Jurassic Otter Point Formation in order to determine if the Canyonville Fault Zone, which forms the northern boundary of the Klamath Mountains in the Riddle - Canyonville area (Benson and Perttu, 1980), extends westward to the coast and, if possible, to characterize the structure of the Otter Point Formation. Further, a detailed examination of the structural and stratigraphic relationships between the Otter Point Formation and the Eocene Roseburg and Lookingglass Formations was to be performed in an attempt to determine the tectonic history of the area.
The Influence Of Halloysite Content On The Shear Strength Of Kaolinite, Reka Katalin Gabor
The Influence Of Halloysite Content On The Shear Strength Of Kaolinite, Reka Katalin Gabor
Dissertations and Theses
The objective of this thesis is to determine the relative shear strengths of halloysite, kaolinite, synthetic mixtures, and local soils, to investigate the influence of halloysite content on the shear strength of kaolinite, and to explore the possibility that the strength properties of soil clays might be controlled by the relative content of their component minerals.
The Stratigraphy And Structure Of The Columbia River Basalt Group In The Bull Run Watershed, Multnomah And Clackamas Counties, Oregon, Beverly Frobenius Vogt
The Stratigraphy And Structure Of The Columbia River Basalt Group In The Bull Run Watershed, Multnomah And Clackamas Counties, Oregon, Beverly Frobenius Vogt
Dissertations and Theses
Approximately 150 meters (500 feet) of Grande Ronde Basalt and 140 meters (450 feet) of Wanapum Basalt of the Columbia River Basalt Group are exposed in the Bull Run Watershed. In Bull Run, the Grande Ronde Basalt is divided into three mappable units: "low Mg" R2 (at least one flow), "low Mg" N2 (approximately four flows), and "high Mg" N2 (two to three flows}. The Wanapum Basalt is represented by two members: Frenchman Springs Member (six flows) and Priest Rapids Member (one flow). These units are identified by instrumental neutron activation analysis, paleomagnetism based on measurements with …
Geology Of A Volcanic Complex On The South Flank Of Mount Jefferson, Oregon, Brian Lee Gannon
Geology Of A Volcanic Complex On The South Flank Of Mount Jefferson, Oregon, Brian Lee Gannon
Dissertations and Theses
The volcanic stratigraphy and petrography is described for a 46 km2 area on the southern flank of Mount Jefferson in the north-central part of the Oregon High Cascades. Here, volcanic processes have been active throughout Quaternary time, resulting in complex stratigraphic relationships. In addition, three formerly recognized glaciations and a two-phase period of neoglaciation have eroded the terrain, depositing tills in contact or interstratified with the volcanic units. Collectively, these processes and the resulting deposits are characteristic of High Cascades development.
Stratigraphy, Lithofacies, And Environment Of Deposition Of The Scappoose Formation In Central Columbia County, Oregon, Kevin Blair Kelty
Stratigraphy, Lithofacies, And Environment Of Deposition Of The Scappoose Formation In Central Columbia County, Oregon, Kevin Blair Kelty
Dissertations and Theses
The study area is located in central Columbia County and encompasses approximately 373 square kilometers. The purpose of the study was to map lithofacies to a scale of 1:31250, study the petrography of the lithofacies, determine the stratigraphy, and develop a model for environment of deposition of the Scappoose Formation.
The Geology And Environment Of Deposition Of The Kinneman Creek Interval, Sentinel Butte Formation (Paleocene), North Dakota, Katherine J. Logan
The Geology And Environment Of Deposition Of The Kinneman Creek Interval, Sentinel Butte Formation (Paleocene), North Dakota, Katherine J. Logan
Theses and Dissertations
To date, most environmental reconstructions of lignite bearing formations in western North Dakota have been done on a formational scale. The objective of this study was to investigate one of the non-lignite intervals, the Kinneman Creek Interval, directly above the strati graphically lowest lignite in the Paleocene Sentinel Butte Formation. The Kinneman Creek Interval has been recognized in the Sentinel Butte Formation throughout most of western North Dakota.
The field area is located in west-central North Dakota in Mercer, Oliver, and McLean Counties and is bi sected by the Missouri River. Excellent exposures are provided in the highwalls of Baukol-Noonan, …
Stratigraphy And Depositional Environments Of The Wilcox Group (Paleocene) At The Oxbow Mine Site, Northwestern Louisiana, Richard E. Halle
Stratigraphy And Depositional Environments Of The Wilcox Group (Paleocene) At The Oxbow Mine Site, Northwestern Louisiana, Richard E. Halle
Theses and Dissertations
The stratigraphy, structure, and depositional environments of the Naborton, Do let Hills, and part of the Cow Bayou Formations (Wilcox Group, Paleocene) at the Oxbow Mine site, Red River, De Soto, and Natchitoches Parishes,. Louisiana, were evaluated from a study of four continuous cores and 466 geophysical logs.
Overlying 40 feet {12 m) of silty Porters Creek shale is the Naborton Formation composed of 130-195 feet (40-59 m) of sand, silt, clay, and lignite. There are three lignites in this formation and their average total thickness is 13.5 feet (4. l m), or about 10% of the formation thickness. The …
The Paleomagnetism Of A Thick Middle Tertiary Volcanic Sequence In Northern California, Douglas Edward Craig
The Paleomagnetism Of A Thick Middle Tertiary Volcanic Sequence In Northern California, Douglas Edward Craig
WWU Graduate School Collection
The mean direction of remanent magnetism for 44 sampling sites from Oligo-Miocene lava flows in northern California points about 12° east of the expected Oligo-Miocene geomagnetic field direction for the area. Our paleomagnetic data and other data indicate that the Cascade Range has rotated clockwise since the middle Tertiary. Similar, but larger, clockwise rotations have been documented in previous studies throughout the Coast Ranges. Two mechanisms are suggested to account for the differential rotation that has occurred within the Coast and Cascade Ranges. First, the Coast Ranges are rotated and then accreted to a curved continental margin during the Eocene, …
The Geology And Mineralogy Of Bentonites And Associated Rocks Of The Chuckanut Formation, Mt. Higgins Area, North Cascades, Washington, Susan Kinder Cruver
The Geology And Mineralogy Of Bentonites And Associated Rocks Of The Chuckanut Formation, Mt. Higgins Area, North Cascades, Washington, Susan Kinder Cruver
WWU Graduate School Collection
In the Mt. Higgins area, the Chuckanut Formation is in probable fault contact with pre-Tertiary metamorphlc rocks. The Chuckanut is over- lain by Oso volcanics (zircon fission track age of 43.2 ± 1.9 MY). A diorite body (k/At date = 53 ± 8 MY) crops out in the Granite Lake area and is thought to be intrusive into the Chuckanut. Sedimentary rocks of much of the study area are dominantly thick- bedded arkoses that are generally cross-bedded, and resemble the Chuckanut type section. Sediments cropping out along and near Deer Creek are different; black, bituminous shale is the dominant rock …