Open Access. Powered by Scholars. Published by Universities.®

Geology Commons

Open Access. Powered by Scholars. Published by Universities.®

Articles 1 - 3 of 3

Full-Text Articles in Geology

A Textural Image Analysis Study Of Mars-Analog Sediment: Comparisons Of 2d And 3d Textural Analysis Methods, Image Resolution, And The Effects Of Shadows, Mary Agnes Eibl Aug 2016

A Textural Image Analysis Study Of Mars-Analog Sediment: Comparisons Of 2d And 3d Textural Analysis Methods, Image Resolution, And The Effects Of Shadows, Mary Agnes Eibl

Masters Theses

Sediments from Mars-analog, basaltic, aeolian (Moses Lake dunes, WA) and fluvial (Death Valley region, CA) environments were analyzed for textural properties (grain size, roundness, sphericity) to understand how well image-based analyses compare with actual sediment characteristics. Three interrelated studies determined: (1) how well high-resolution, two-dimensional (2D) image analysis compares with three-dimensional (3D) sediment textures, (2) the extent to which decreasing image resolution affects textural analyses by comparison with high-resolution images, and (3) the extent to which shadows at different incident solar angles has on textural measurements. In both aeolian and fluvial environments, 2D grain-size distributions and statistics closely match 3D …


Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle Jan 2016

Phosphorus Retention In A Lowland Neotropical Stream Following An Eight-Year Enrichment Experiment, Gaston E. Small, Marcelo Ardón, John H. Duff, Alan P. Jackman, Alonso Ramírez, Frank J. Triska, Catherine M. Pringle

United States Geological Survey: Staff Publications

Human alteration of the global P cycle has led to widespread P loading in freshwater ecosystems. Much research has been devoted to the capacity of wetlands and lakes to serve as long-term sinks for P inputs from the watershed, but we know much less about the potential of headwater streams to serve in this role. We assessed storage and retention of P in biotic and abiotic compartments after an 8-y experimental P addition to a 1st-order stream in a Neotropical wet forest. Sediment P extractions indicated that nearly all P storage was in the form of Fe- and Al-bound P …


3d Structural And Stratigraphic Architecture Of The Northwest Santa Barbara Basin And Implications For Submarine Landslide Generation, Alexis Wright Jan 2016

3d Structural And Stratigraphic Architecture Of The Northwest Santa Barbara Basin And Implications For Submarine Landslide Generation, Alexis Wright

Dissertations and Theses

Multiple submarine landslides have been previously documented on the north flank of the Santa Barbara Channel, and such failures are considered to be capable of generating local tsunamis hazards to the Santa Barbara region. 2D seismic-reflection datasets provide a general view of regional framework geology, including faulting and folding associated with north-south compression. However, better understanding of the relationships between faults, folds, stratigraphic architecture, and submarine landslides can be obtained with 3D seismic datasets. In this study we use an industry 3D seismic-reflection volume that encompasses the slope and shelfbreak surrounding the Gaviota submarine landslide (3.8 km2) to investigate structural …