Physical Sciences and Mathematics Commons^™

Cretaceous Paleomagnetism Of The Methow-Pasayten Belt, Washington, Russ R. Burmester, Myrl E. Beck Jr., Julian L. Granierer

Geology Faculty Publications

Detailed demagnetization experiments isolated a characteristic remanent magnetization in ten stable sites from the upper Cretaceous Winthrop and Midnight Peak Formation in the Methow-Pasayten belt of north-central Washington. This remanence agrees best between opposite limbs of a fold (the Goat Peak syncline) when corrected for 46% of tilt. This is consistent with magnetization acquired during deformation. Synfolding magnetization may have been facilitated by a thermo-chemical event associated with synkinematic intrusions along the axis of folding. The mean direction (D=12.0°, I=61.1°, Alpha-95=4.8°) is highly discordant with respect to the expected direction for north-central Washington. This discordance points to about 1,400 km …

Paleomagnetism Of Middle Tertiary Volcanic-Rocks From The Western Cascade Series, Northern California, Myrl E. Beck Jr., Russ R. Burmester, Douglas E. Craig, C. Sherman Gromme, Ray E. Wells

Geology Faculty Publications

The Western Cascade Series (WCS) is a 3.5-km-thick, crudely homoclinal (east dipping) calcalkaline volcanic sequence of mid-Oligocene to early Miocene age that crops out near the southern tip of the Cascade Range in northern California. The mean direction of remanent magnetization in the WCS is D, 4.9°; I, 57.6° (N, 53; k, 14.4; α₉₅ , 5.3°). When compared to a reference direction for the North American cration, the WCS direction indicates that the southern Cascade Range has rotated 14.0° +/- 9.0° since the WCS accumulated. A difference in mean direction between the lower and upper halves of the WCS …

Transient Electromagnetic Sounding For Groundwater, David V. Fitterman, Mark T. Stewart

Geology Faculty Publications

The feasibility of using the transient electromagnetic sounding (TS or TDEM) method for groundwater exploration can be studied by means of numerical models. As examples of its applicability to groundwater exploration, we study four groundwater exploration problems: (1) mapping of alluvial fill and gravel zones over bedrock; (2) mapping of sand and gravel lenses in till; (3) detection of salt or brackish water interfaces in freshwater aquifers; and (4) determination of hydrostratigraphy. These groundwater problems require determination of the depth to bedrock; location of resistive, high-porosity zones associated with fresh water; determination of formation resistivity to assess water quality; and …

Tertiary Peleomagnetism Of The North Cascade Range, Washington, Myrl E. Beck Jr., Russ R. Burmester, Ruth Schoonover

Geology Faculty Publications

We have obtained paleomagnetic data for the southern tiip of the middle Tertiary Chilliwack Composite Batholith, located on the Canada-United States border about 125 km E of Vancouver, B.C. Thirty-four separately oriented samples were collected along a road traverse 1.5 km long located along State Highway 22, about 20 km NE of Marblemount, Washington. The mean direction after magnetic cleaning is: D, 182.8°; I, -65.0°; α₉₅, 1.5°. This corresponds to a paleomagnetic pole at 87.5°N, 267.5°E, close to other poles for Tertiary plutons from the North Cascades and only slightly displaced from Tertiary reference poles from the craton. …

Pennsylvanian And Early Permian Depositional Framework, Southeastern Arizona, Charles A. Ross

Geology Faculty Publications

This summary of the Pennsylvanian and Early Permian depositional framework in southeastern Arizona and adjacent regions is based in large part on the data and conclusions presented earlier in more detail by Ross (1973, 1978). The general stratigraphy of the Pedregosa, Orogrande and Permian basins and much of the literature has recently been summarized by Greenwood and others (1977).

In southeastern Arizona, Pennsylvanian and Permian strata are well exposed in many of the Basin and Range uplifts, where they may be studied in considerable detail. Mesozoic and Cenozoic structures, including local thrust faulting, and the attendant possibility of considerable lateral …

Fusulinids From The Cyathophyllum Limestone, Central Vestspitsbergen, Charles A. Ross

Geology Faculty Publications

Thirteen species of fusulinids are illustrated and described from eleven collections within the Cyathophyllum Limestone of central Vestspitsbergen. The lower collections at Tempelfjorden and the collection from Mount Lykta contain Schubertella transitoria, Triticites arcticus, and Schwageriiia anderssoni and other species typical of the Carboniferous zones C₃C through C₃E of the Ural region of the U.S.S.R. It is suggested that “Fusulinella" usvae is a species of Waeringella. Higher collections at Tempelfjorden include Parafusulina furnishi n. sp. and Pseudofusulinella tempelensis n. sp. and a loose block from higher in the succession includes Schwagerina …

Early Permian Fusulinids From Macusani, Southern Peru, Charles A. Ross

Geology Faculty Publications

Triticites patulus Dunbar and Newell and Schwagerina adamsi sp. nov. from the early Wolfcampian (Permian) part of the Copacabana Group near Macusani, southern Peru, show morphological features that add new data concerning the evolution of the genera Schwagerina and Pseudoschwagerina from lineages arising within the genus Triticites near the close of the Pennsylvanian.

Fusulinids From The Leonard Formation (Permian), Western Glass Mountains, Texas, Charles A. Ross

Geology Faculty Publications

From the Leonard Formation in the western part of the Glass Mountains, eleven species of fusulinids are recognized. The lowest member of the formation, member A, has Schwagerina dugoutensis n. sp., S. hawkinsi Dunbar and Skinner, S. hessensis Dunbar and Skinner, S. crassitectoria Dunbar and Skinner, S. guembeli Dunbar and Skinner, Monodiexodina linearis (Dunbar and Skinner), Parafusulina leonardensis n. sp., and P. allisonensis Ross. The middle member, member B, contains Schwagerina hessensis, S. hawkinsi?, Parafusulina spissisepta Ross, P. leonardensis, and Schubertella muellerriedi Thompson and Miller. Member C at the top of the formation has the distinctive species …

Permian Foraminifera From British Honduras, Charles A. Ross

Geology Faculty Publications

Fusulinids identified from the Macal Shale Group, Macal Series, south central British Honduras and Schwarerina gruperaensis Thompson and Miller, Schwagerina sp. A, Eoverbeekina aff. E. americana Thompson and Miller, Ozawainella? sp., and Staffella sp. One species of the Trochamminid genus Tetrataxis also occurs in these strata. These species suggest correlation with the lower part of the Chochal Limestone of Guatemala, the Grupera Formation of Chiapas, Mexico, and the Lenox Hills Formation (upper part of the standard Wolfcampian Series, Permian), Glass Mountains, Texas.

Fusulinids From The Hess Member Of The Leonard Formation, Leonard Series (Permian), Glass Mountains, Texas, Charles A. Ross

Geology Faculty Publications

Five fusulinid zones are recognizable in the Hess member of the Leonard formation in the eastern Glass Mountains. These zones are useful for correlation and contain two species of Schwagerina, previously described, and five species of Parafusulina which are new. The assemblage of Schwagerina crassitectoria Dunbar and Skinner and S. gaembeli Dunbar and Skinner forms the lowest zone, Parafusulina allisonensis n. sp. forms the second zone, P. deitoides n. sp. and Parafusulina sp. A form the third zone. P. spissisepta n. sp. forms the fourth zone which includes the upper Hess fossil bed of P. B. King (1931), and …