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E.P. Kvale

Publications and source records attributed to E.P. Kvale.

9 recordsLinked to original sources

The art, history, and geoscience of Hindustan Whetstone gravestones in Indiana

Cemeteries can be intriguing places to people, in part because of a fascination with death but also because of the quiet solitude and artistic beauty found there. Many grave monuments are really works of art and can be appreciated on that basis alone. Cemeteries can also serve as teaching laboratories for geologists. Monument types, carving styles, ornamentation, and durability are all related, to some extent, to the type of rock used. The older the monument dates the more variability one can see in the character of the stones. Pioneer cemeteries in southern Indiana, some of which date back to the early 1800s, can be used to teach concepts in mineralogy, depositional environments, and paleoastronomy. This can be very useful to someone teaching some of the basic concepts of geology.

Indiana↗

Paleovalley fills: Trunk vs. tributary

A late Mississippian-early Pennsylvanian eustatic sea level drop resulted in a complex lowstand drainage network being eroded across the Illinois Basin in the eastern United States. This drainage system was filled during the early part of the Pennsylvanian. Distinct differences can be recognized between the trunk and tributary paleovalley fills. Fills preserved within the trunk systems tend to be fluvially dominated and consist of bed-load deposits of coarse- to medium-grained sandstone and conglomerate. Conversely, the incised valleys of tributary systems tend to be filled with dark mudstone, thinly interbedded sandstones, and mudstones and siltstones. These finer grained facies exhibit marine influences manifested by tidal rhythmites, certain traces fossils, and macro- and microfauna. Examples of tributary and trunk systems, separated by no more than 7 km (4.3 mi) along strike, exhibit these styles of highly contrasting fills. Useful analogs for understanding this Pennsylvanian system include the Quaternary glacial sluiceways present in the lower Ohio, White, and Wabash river valleys of Indiana (United States) and the modern Amazon River (Brazil). Both the Amazon River and the Quaternary rivers of Indiana have (or had) trunk rivers that are (were) dominated by large quantities of bed load relative to their tributaries. The trunk valley systems of these analogs aggraded much more rapidly than their tributary valleys, which evolved into lakes because depositional rates along the trunk are (were) so high that the mouths of the tributaries have been dammed by bed-load deposits. These Holocene systems illustrate that sediment yields can significantly influence the nature of fill successions within incised valleys independent of rates of sea level changes or proximity to highstand coastlines. Copyright ?? 2007. The American Association of Petroleum Geologists. All rights reserved.

American Association of Petroleum Geologists Bulle↗

The origin of neap-spring tidal cycles

The origin of oceanic tides is a basic concept taught in most introductory college-level sedimentology/geology, oceanography, and astronomy courses. Tides are typically explained in the context of the equilibrium tidal theory model. Yet this model does not take into account real tides in many parts of the world. Not only does the equilibrium tidal model fail to explicate amphidromic circulation, it also does not explain diurnal tides in low latitude positions. It likewise fails to explain the existence of tide-dominated areas where neap-spring cycles are synchronized with the 27.32-day orbital cycle of the Moon (tropical month), rather than with the more familiar 29.52-day cycle of lunar phases (synodic month). Both types of neap-spring cycles can be recognized in the rock record. A complete explanation of the origin of tides should include a discussion of dynamic tidal theory. In the dynamic tidal model, tides resulting from the motions of the Moon in its orbit around the Earth and the Earth in its orbit around the Sun are modeled as products of the combined effects of a series of phantom satellites. The movement of each of these satellites, relative to the Earth's equator, creates its own tidal wave that moves around an amphidromic point. Each of these waves is referred to as a tidal constituent. The geometries of the ocean basins determine which of these constituents are amplified. Thus, the tide-raising potential for any locality on Earth can be conceptualized as the result of a series of tidal constituents specific to that region. A better understanding of tidal cycles opens up remarkable opportunities for research on tidal deposits with implications for, among other things, a more complete understanding of the tidal dynamics responsible for sediment transport and deposition, changes in Earth-Moon distance through time, and the possible influences tidal cycles may exert on organisms. ?? 2006 Elsevier B.V. All rights reserved.

Marine Geology↗

Late Albian Kiowa-Skull Creek marine transgression, lower Dakota Formation, eastern margin of Western Interior Seaway, U.S.A

An integrated geochemical-sedimentological project is studying the paleoclimatic and paleogeographic characteristics of the mid-Cretaceous greenhouse world of western North America. A critical part of this project, required to establish a temporal framework, is a stratigraphic study of depositional relationships between the Albian-Cenomanian Dakota and the Upper Albian Kiowa formations of the eastern margin of the Western Interior Seaway (WIS). Palynostratigraphic and sedimentologic analyses provide criteria for the Dakota Formation to be divided into three sedimentary sequences bounded by unconformities (D 0 , D 1 , and D 2 ) that are recognized from western Iowa to westernmost Kansas. The lowest of these sequences, defined by unconformities D 0 and D 1 , is entirely Upper Albian, and includes the largely nonmarine basal Dakota (lower part of the Nishnabotna Member) strata in western Iowa and eastern Nebraska and the marine Kiowa Formation to the southwest in Kansas. The gravel-rich fluvial deposits of the basal part of the Nishnabotna Member of the Dakota Formation correlate with transgressive marine shales of the Kiowa Formation. This is a critical relationship to establish because of the need to correlate between marine and nonmarine strata that contain both geochronologic and paleoclimatic proxy data. The basal gravel facies (up to 40 m thick in western Iowa) aggraded in incised valleys during the Late Albian Kiowa-Skull Creek marine transgression. In southeastern Nebraska, basal gravels intertongue with carbonaceous mudrocks that contain diverse assemblages of Late Albian palynomorphs, including marine dinoflagellates and acritarchs. This palynomorph assemblage is characterized by occurrences of palynomorph taxa not known to range above the Albian Kiowa-Skull Creek depositional cycle elsewhere in the Western Interior, and correlates to the lowest of four generalized palynostratographic units that are comparable to other palynological sequences elsewhere in North America. Tidal rhythmites in mudrocks at the Ash Grove Cement Quarry in Louisville (Cass County), Nebraska record well-developed diurnal and semimonthly tidal cycles, and moderately well developed semiannual cycles. These tidal rhythmites are interpreted to have accumulated during rising sea level at the head of a paleoestuary that experienced at least occasional mesotidal conditions. This scenario places the gravel-bearing lower part of the Nishnabotna Member of the Dakota Formation in the mouth of an incised valley of an Upper Albian transgressive systems tract deposited along a tidally influenced coast. Furthermore, it provides a depositional setting consistent with the biostratigraphic correlation of the lower part of the Nishnabotna Member of the Dakota Formation to the marine Kiowa Formation of Kansas.

Iowa↗

Organic geochemistry in Pennsylvanian tidally influenced sediments from SW Indiana

Tidal rhythmites are vertically stacked small-scale sedimentary structures that record daily variations in tidal current energy and are known to overlie some low-sulfur coals in the Illinois Basin. Tidal rhythmites from the Pennsylvanian Brazil Formation in Indiana have been analyzed sedimentologically, petrographically, and geochemically in order to understand the character and distribution of organic matter (OM) preserved in an environment of daily interactions between marine and fresh waters. The concentration of organic matter (TOC) ranges from traces to 6.9% and sulfur rarely exceeds 0.1% in individual laminae. Angular vitrinite is the major organic matter type, accounting for 50-90% of total OM. The C/S ratio decreases as the verfical distance from the underlying coal increases. A decreasing C/S ratio coupled with decreases in Pr/Ph, Pr/n-C17, Ph/n-C18 ratios and a shift of carbon isotopic composition towards less negative values suggest an increase in salinity from freshwater in the mudflat tidal rhythmite facies close to the coal to brackish/marine in the sandflat tidal rhythmite facies further above from the coal. Within an interval spanning one year of deposition, TOC and S values show monthly variability. On a daily scale, TOC and S oscillations are still detectable but they are of lower magnitude than on a monthly scale. These small-scale variations are believed to reflect oscillations in water salinity related to tidal cycles.Tidal rhythmites are vertically stacked small-scale sedimentary structures that record daily variations in tidal current energy and are known to overlie some low-sulfur coals in the Illinois Basin. Tidal rhythmites from the Pennsylvanian Brazil Formation in Indiana have been analyzed sedimentologically, petrographically, and geochemically in order to understand the character and distribution of organic matter (OM) preserved in an environment of daily interactions between marine and fresh waters. The concentration of organic matter (TOC) ranges from traces to 6.9% and sulfur rarely exceeds 0.1% in individual laminae. Angular vitrinite is the major organic matter type, accounting for 50-90% of total OM. The C/S ratio decreases as the vertical distance from the underlying coal increases. A decreasing C/S ratio coupled with decreases in Pr/Ph, Pr/n-C17, Ph/n-C18 ratios and a shift of carbon isotopic composition towards less negative values suggest an increase in salinity from freshwater in the mudflat tidal rhythmite facies close to the coal to brackish/marine in the sandflat tidal rhythmite facies further above from the coal. Within an interval spanning one year of deposition, TOC and S values show monthly variability. On a daily scale, TOC and S oscillations are still detectable but they are of lower magnitude than on a monthly scale. These small-scale variations are believed to reflect oscillations in water salinity related to tidal cycles.

Organic Geochemistry↗

Organic geochemical study of sequences overlying coal seams; example from the Mansfield Formation (Lower Pennsylvanian), Indiana

Roof successions above two coal seams from the Mansfield Formation (Lower Pennsylvanian) in the Indiana portion of the Illinois Basin have been studied with regard to sedimentary structures, organic petrology and organic geochemistry. The succession above the Blue Creek Member of the Mansfield Formation is typical of the lithologies covering low-sulphur coals (< 1%) in the area studied, whereas the succession above the unnamed Mansfield coal is typical of high-sulphur coals (>2.%). The transgressive-regressive packages above both seams reflect the periodic inundation of coastal mires by tidal flats and creeks as inferred from bioturbation and sedimentary structures such as tidal rhythmites and clay-draped ripple bedforms. Geochemistry and petrology of organic facies above the Blue Creek coal suggest that tidal flats formed inland in fresh-water environments. These overlying fresh water sediments prevented saline waters from invading the peat, contributing to low-sulphur content in the coal. Above the unnamed coal, trace fossils and geochemical and petrological characteristics of organic facies suggest more unrestricted seaward depositional environment. The absence of saline or typically marine biomarkers above this coal is interpreted as evidence of very short periods of marine transgression, as there was not enough time for establishment of the precursor organisms for marine biomarkers. However, sufficient time passed to raise SO 4 2− concentration in pore waters, resulting in the formation of authigenic pyrite and sulphur incorparation into organic matter.

International Journal of Coal Geology↗

Late Proterozoic and Paleozoic tides, retreat of the moon, and rotation of the earth

The tidal rhythmites in the Proterozoic Big Cottonwood Formation (Utah, United States), the Neoproterozoic Elatina Formation of the Flinders Range (southern Australia), and the Lower Pennsylvanian Pottsville Formation (Alabama, United States) and Mansfield Formation (Indiana, United States) indicate that the rate of retreat of the lunar orbit is d ξ/ dt ∼ k 2 sin(2δ) (where ξ is the Earth-moon radius vector, k 2 is the tidal Love number, and δ is the tidal lag angle) and that this rate has been approximately constant since the late Precambrian. When the contribution to tidal friction from the sun is taken into account, these data imply that the length of the terrestrial day 900 million years ago was ∼18 hours.

Alabama, Indiana, Utah↗

Comparison of drier- to wetter-interval estuarine roof facies in the Eastern and Western Interior coal basins, USA

Many of the Carboniferous coals in the eastern interior of the US are associated with siliciclastic roof facies that were deposited within a fluvio-estuarine transition. These facies include a variety of rhythmites, some of which exhibit tidal cycles. Drier-interval coals (Westphalian B-C, Stephanian) tend to be more laterally restricted and more commonly are associated with paleovalleys. Conversely, wetter-interval coals (Westphalian D) are very widespread and are not restricted to paleovalleys. Throughout the Lake Carboniferous, wet paleoclimates associated with these coals lead to valley incision during sea-level lowstand when large tropical rivers downcut older sediments deposited during previous sea-level highstands. During subsequent rise of sea level, these fluvial valleys were flooded and converted to estuaries where tidal ranges and sedimentation rates were significantly amplified. Based on modern analogs and interpretation of many examples of Carboniferous tidal rhythmites, the localized depositional rates in these settings are exceptionally high. The estuaries became sediment sinks, trapping sediment that is pumped in from both fluvial and marine sources. As a result, sedimentation readily keeps pace with rising baselevel. Extensive intertidal flats and shallow subtidal flats are created and prograde over the valley-confined mires. Thick tidal cycles and upright trees (some with attached foliage) record rapid burial of mires. This model is supported with examples of roof facies from the Westphalian B-C of the Eastern Interior Basin, and the Stephanian of the Western Interior Basin. In these areas facies within each cycle range from well-developed, extensive paleosols and coals, to widespread marine shales or limestones. Variations in both sea level and climate resulted in a complex history of valley fill during which coals could be developed at any time (except during widespread flooding). Minable, low-sulfur and low-ash coals occur, but the coals are relatively thin and discontinuous. Conversely, the Westphalian D coals are very widespread and significant peat accumulations were not confined to paleovalleys. Nonetheless, the lowest sulfur coals are related to rapid deposition of roof facies that occurred within the paleovalley whereas high-sulfur coals were formed in areas of lower sedimentation rate of roof facies that occurred beyond the confines of the paleovalley.

Arkansas, Illinois, Indiana, Iowa, Kansas, Kentuck↗