The Compass: Earth Science Journal of Sigma Gamma Epsilon

Digital Repository Material Contribution Form

Thu, 31 Jan 2013 14:45:37 PST

Instructions to Authors

Thu, 31 Jan 2013 14:45:36 PST

Has The Compass, as an E-journal, Been Successful?

Larry E. Davis — Thu, 31 Jan 2013 14:45:35 PST

Introducing Dr. Aaron W. Johnson, Associate Editor of The Compass

Aaron W. Johnson — Thu, 31 Jan 2013 14:45:35 PST

Holocene Pedogenesis in Fluvial Deposits of the Conejos River Valley, Southern Colorado

Anthony L. Layzell et al. — Thu, 31 Jan 2013 14:45:34 PST

Relatively few geomorphic studies have examined Holocene-aged soils developed in alluvial deposits in the Rocky Mountains. Here, we present a soil morphological investigation from a suite of fluvial terraces in the glaciated portion of the Conejos River Valley, southern Colorado. The surficial geology of 25 km of the glacial valley was mapped in detail. Within three separate sub-reaches (Platoro, Lake Fork and South Fork) a total of thirteen soil pits and exposures were excavated and described on alluvial deposits. Soil samples were analyzed for particle size and extractable iron.

Soil horizonation (A/C to A/B/2C), structure (fine sub angular to medium angular blocks), clay content of the B horizon (8.0% to 22.8%) and Feo/Fed (0.39 to 0.80) illustrate trends with relative terrace deposit age in individual sub-reaches. However, only Feo/Fed ratios displayed similar rates of development between all sub-reaches highlighting the usefulness of this metric for determining accurate rates of pedogenesis and relative age for Holocene-aged deposits in sub-alpine environments. Results indicate that clay content and structure developed in alluvial deposits of similar ages vary between sub-reaches. Clay contents were found to be lower in the Platoro sub-reach (e.g. 13.1% at Platoro and 20.0% at South Fork on Qt1 deposits). This variation is attributed to heterogeneity in the nature of the inherited parent material and potential variability in aeolian dust contributions throughout the Holocene.

Plains-type Folds: Their Origin and Development

Dan Merriam — Thu, 31 Jan 2013 14:45:32 PST

Small in areal extent, plains-type folds in Paleozoic sediments of the Midcontinent of the United States form by as the result of draping sediments over highs in underlying Precambrian crystalline basement rocks. Fracture systems in underlying Precambrian rocks may propagate upward through overlying sedimentary rocks. Movement on the basement structures occur when there is an adjustment in the basement, which results in an adjustment of the overlying units and a draping over the tilted fault blocks. The incidence of earthquakes, which result from this adjustment, are recorded in the overlying sediment as convolute features known as seismites.

Key Words or Keywords

Dan Merriam — Thu, 31 Jan 2013 14:45:30 PST

Keywords are words or phrases which describe content. With the emergence of computerized data bases, keywords are important research tools for search engines, such as GeoRef. Keywords help to ‘tag’ relevant information within an article, and provide a researcher with useful clues to potential important and useful information.

In Memorium: Dr. Charles J. Mankin, 1932-2012 Past National Secretary-Treasurer of Sigma Gamma Epsilon

Kenneth S. Johnson — Thu, 31 Jan 2013 14:45:28 PST

Sigma Gamma Epsilon Undergraduate Research Poster Session

Erika Elswick — Wed, 12 Sep 2012 10:45:56 PDT

The Sigma Gamma Epsilon undergraduate research poster session will highlight recent and on-going student research. Abstracts for poster presentations will be available in the Geological Society of America Abstracts with Programs, 2012 Annual Meeting, Charlotte, North Carolina, 4-7 November 2012.

Sigma Gamma Epsilon-News and Information

James Walters — Fri, 07 Sep 2012 13:05:25 PDT

Dinosaur Tracks and Trackways in the Escalante Member of the Entrada Formation (Middle Jurassic), Twentymile Wash, Grand Staircase-Escalante National Monument, Utah

Robert L. Eves et al. — Fri, 07 Sep 2012 13:05:23 PDT

Geology and Music

Dan Merriam — Fri, 07 Sep 2012 13:05:21 PDT

Heavy Metal Chemistry of Sediments in Caves of the Springfield Plateau, Missouri-Arkansas-Oklahoma: A Link to Subterranean Biodiversity

Travis M. Doughty et al. — Fri, 07 Sep 2012 13:05:19 PDT

We used X-ray fluorescence (XRF) to compare the heavy metal chemistry of sediments in caves in rural and urban areas to the chemistry of sediments from a control cave in a relatively undisturbed watershed in the Springfield (MO) Plateau. Sediment from Smallin Cave near Ozark, MO, the control cave, has the smallest peak sizes for Zn and Mn and a moderately-sized Pb peak. Sediment from the rural cave exhibited larger peaks of Zn and Mn and a smaller Pb peak. Sediment from the urban cave had the largest Zn, Mn and Pb peaks. Interestingly, smaller peak sizes appear to correlate to the presence of aquatic troglobites. The control cave hosts the most diverse troglobitic fauna and has sediment with smaller peak sizes. Ruark caves are rural caves, and are barren of troglobites and have sediment with larger peak sizes. Giboney Cave, an urban cave in Doling Park in Springfield, MO, provides the most interesting evidence. Giboney Cave splits into two branches, each of which has a unique chemical fingerprint. One channel is barren of cave life and has sediment that exhibits large metal peaks. The second channel hosts aquatic troglobites and has sediment that has small metal peaks. These findings are of particular importance because the caves of the Springfield Plateau host abundant troglobitic species, including the endangered Ozarks cavefish (Amblyopsis rosae). Sediment metal concentrations may indicate which cave systems are capable of supporting life, with XRF analysis providing a non-destructive, rapid way to identify such systems.

Is Geology a Real Science?

Larry E. Davis — Fri, 07 Sep 2012 13:05:18 PDT

Sigma Gamma Epsilon - News and Information

Erika Elswick — Tue, 17 Apr 2012 11:37:24 PDT

An Assessment of the Relationship between Air Mass Frequency and Extreme Drought in the Midwest United States

Curtis Walker et al. — Tue, 17 Apr 2012 11:37:22 PDT

The Midwest of the United States is a region extensively utilized for agriculture and livestock production despite great susceptibility to widespread and persistent drought. While the location and duration of droughts are related to dynamic meteorological factors, pinpointing when and where a drought will commence, how long it will persist, and when the drought will end, remains a challenge. This investigation examines significant Midwest drought events from a synoptic meteorological perspective through an assessment of air mass frequency over the past decade. A synoptic approach is useful since air masses characteristically describe multiple weather and climate parameters at the same time across wide areas. The daily air mass conditions in the Spatial Synoptic Classification that are dominant during extreme droughts are examined across the region and compared to “normal” periods without substantial or extensive drought. Extreme episodes are established with new criteria expanded from United States Drought Monitor information, normal average decadal and seasonal baselines are calculated, and the air mass frequency departures from these periods are examined for statistical and practical significance. Results indicate that the Dry Polar, Dry Tropical and Moist Tropical air masses exhibit important and statistically significant changes in frequency during drought. Tendencies for substantial increases in warm and dry types, regardless of season, and moist air mass declines are detected. The exact air masses with significant changes are unique for different sub-regions, particularly in the northwest and south. These patterns are consistent with changing upper-air flows such as southerly, meridional flow to more southwesterly, zonal flow.

Herbert Hoover: Only an Eye for Gold?

Larry E. Davis — Tue, 17 Apr 2012 11:37:21 PDT

Herbert Hoover, 31st President of the United States, was a successful mining engineer and author prior to becoming president. Part of his mining engineering career was spent in the goldfields of Western Australia, where he has become part of the local folklore. Hoover allegedly had an eye for the ladies and fell in love with a barmaid to whom he wrote a love poem.

U.S. Presidents and their Geological Thinking

Dan Merriam — Tue, 17 Apr 2012 11:37:20 PDT

A number of United States presidents had some experience in geological thought and investigations and keen interests in the environment. The first U.S. president, George Washington, was a land surveyor. Thomas Jefferson, the 3rd U.S. president, was a keen supporter of science and maintained an interest in paleontology, and played a key role in the development of American paleontology. Theodore Roosevelt, the 26th U.S. president, was a strong supporter of the national park service and was an influential naturalist.

Herbert Hoover, the 31st U.S. president, was a Stanford University graduate with a degree in geology and mining – a true geologist/U.S. President. Hoover worked in the mining industry in the western United States, Australia, and China before moving into politics. Hoover lectured on mining at both Columbia and Stanford Universities and his lectures were published in 1909 as Principles of Mining. In 1912, Hoover, with his wife Lou Henry, translated Agricola‟s De Re Metallica from Latin into English.

Another Geoscience Department 'Bites the Dust'

Larry E. Davis — Tue, 17 Apr 2012 11:37:19 PDT

Letter to the Members of SGE

Erika Elswick — Tue, 17 Apr 2012 11:37:18 PDT