The effects of downward gravity wave reflection from atmospheric structure and horizontal winds; the geometry of the wave source and observation region; and the relative importance of the horizontal and vertical transport are being investigated for several different but often used gravity wave models. A quantitative study is also made on the relative importance of the purely gravitationally induced compression (G.I.C.) due to fluid particle altitude change and the actual wave compression which can occur at a fixed altitude in a gravity wave.
Petrographic study of the Deicke and Millbrig K-benonite beds (altered volcanic ash) of Rocklandian age has revealed that they can be distinguished by their non-clay mineralogy. The Deicke phenocryst assemblage is primarily labradorite, Fe-Ti oxides, apatite, and zircon, while the Millbrig assemblage is primarily andesine, quartz, biotite, apatite, and zircon. The Deicke is altered dacitic ash, while the Millbrig is altered rhyodacitic ash.
The petrographic and compositional characteristics of detrital magnetite and ilmenite separated from 31 modern sand samples derived from 8 known igneous and metamorphic parent rocks indicates that magnetite is a useful provenance indicator. In contrast, detrital ilmenite shows no trends with variations in parent rock and its use in provenance research is suspect.
The hydrology of a thin colluvium hillside at the Delhi Pike landslide complex, approximately 15 km west of downtown Cincinnati, is controlled by infiltration and evapotranspiration. Pore water pressures approach $-$10 m H$\sb2$O during summer and autumn, but rise to $-$1 m H$\sb2$O or higher after several days of steady winter rains. This state of near saturation is maintained until large trees leaf out and pore pressures fall dramatically in late spring.
Organic carbon (C) and sulfide sulfur (S) contents of host rocks and ore bodies selected from four manganese carbonate deposits were tested and plots of carbon against sulfur of the type proposed by Berner were used to distinguish depositional environments.
A unified study of outcrop and subsurface Silurian rocks from the Brassfield Formation through the C unit in adjacent portions of Ohio, Kentucky, and West Virginia enhances our understanding of regional stratigraphy, paleogeography, and sea level variations.
In east-central Utah, tide-, wind-, and wave-currents deposited the Middle Jurassic (Callovian) Curtis and Summerville Formations and the Moab Member of the Entrada Sandstone along the southern and eastern coastal plain of an interior seaway. Four facies of the Curtis were deposited during maximum transgression and incipient regression. Interbedded, heterogeneous litharenite and sublitharenite microsequences in the sandstone-mudstone facies record the initial transgression and development of sedimentation on a nearshore shelf. Sand and mud were intermittently transported by tidal- and wave-currents at near wavebase depths. The composite sandstone facies contains amalgamated, crossbedded and parallel-bedded subarkosic microsequences which were deposited during late transgression, stillstand and incipient regression in a tidal channel, sand-shoal, berm system. Sand, silt and mud were transported in the form of ripples, sand waves and dunes in tidal channels controlled by spring and neap tidal current. At shallower intertidal depths, interchannel sand shoals and berms were constructed by plane- and cross-laminated strata. Contemporary crosslaminated and locally crossbedded sublitharenites in the rippled silty facies and the redbed facies were deposited by spring-tide and wind- or storm-enhanced tidal currents in higher intertidal and supratidal zones respectively.
The Aspen Grove landslide, central Utah, occurred in older landslide debris. The debris is about 6-15 meters thick, and consists of medium- to high-plasticity clays and silty clays. Persistent landslide structures, including toes, hollows, and flank ridges, outline dimly preserved landslide masses in the older debris.
Slaty cleavage exposed in the fine-grained metasediments of western Ocoee Gorge, Tennessee is characterized by zones enriched in cleavage-parrallel white mica (P domains), alternating with zones enriched in quartz and feldspar and in which phyllosilicates are bedding-parallel (Q domains). This domainal fabric appears to develop by growth of new mica from mica components carried in a moving fluid. Solid state recrystallization of clays and mica may also have contributed to the development of the fabric, but little, if any, mechanical rotation or passive concentration of mica grains occurred. Both P domain morphology and mineralogical differences between P and Q domain phyllosilicate populations suggest that nucleation and growth of P domains may involve the expulsion of fluids, during diagenesis and low-grade metamorphism.
Roots of white ash have a better configuration than roots of sugar maple for anchoring shallow colluvium against landsliding on hillslopes along the Ohio River and its tributaries in southwestern Ohio. The landslides are in a shallow layer of colluvium, about one meter thick, overlying shale and limestone bedrock. The sliding hillsides range in slope angle from 16 to 36 degrees and the roots which penetrate shear surfaces are anchored in the weathered bedrock and help to hold landmasses in place. The hillsides are covered by a mesophytic forest, locally known as a ravine community, dominated by white ash, sugar maple and sweet buckeye. Sugar maple is the most common species on the landslides; its roots do not penetrate the soil as deeply as the roots of the white ash.