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1.
A differential approach to map comparison and integration is presented utilizing the variance-covariance matrices of polynomial trend surfaces. The approach is based on the statistics presented in the trend-surface computer program, CORSURF. Examples in south-central Kansas and the Maracaibo Basin in Venezuela are presented to show how the technique could be used in basinanalysis studies. 相似文献
2.
The taxonomic status of previously misplaced species of an ant-like stone beetle from Spanish amber (Albian) is clarified. Specimens of Kachinus magnificus (originally placed as incertae sedis within Scydmaenitae) were re-examined and their characters were found different from those of the type species of Kachinus from Myanmar amber. Consequently, Archeutheia gen. nov. is proposed to accommodate the Spanish species, resulting in Archeutheia magnifica comb. nov. Moreover, in a comprehensive phylogenetic analysis Archeutheia was placed as a sister group to extant Eutheia, within the tribe Eutheiini of Cephenniitae. A specimen of an undetermined genus from Myanmar amber clearly belonging in Cephenniini is also recorded. Both taxa represent the first definite Cretaceous Cephenniitae, a supertribe whose recent members are distributed on all continents but are especially diverse in the Oriental and East Palaearctic regions. This finding demonstrates a diversification of two presently most species-rich tribes of Cephenniitae already in Early Cretaceous. Archeutheia is strikingly similar to the extant species of Eutheia and Veraphis, showing male dimorphic characters (modified protrochanters) and antennal cavities characteristic of Palaearctic Eutheiini. This fact suggests a long morphological stability in the supertribe. A previously proposed hypothesis of an early presence of the Cephenniitae in the Northern Hemisphere is for the first time supported by the fossil record, and the palaeolocalities (western Europe and Southeast Asia) demonstrate a wide distribution of Cephenniitae in the Cretaceous and an early split of its ancestral lineage. 相似文献
3.
Conflicts between different interest groups for use of natural resources is one area where state geological surveys can provide
assistance. A state geological survey working within the scientific constraints of specific issues can remain objective in
its presentations and maintain the faith of both the conflicting interest groups and the public. One cannot vary from the
objective view or you will quickly be criticized. Criticism can still occur from one side of a natural resource issue as your
data might counter their views. However, the final decisions are almost always made in some legislators, or regulators, area
of responsibility. The responsibility of the state geological survey is to provide the important data that will assist in
making correct decisions. Should one party in the conflict become extreme in their demands, a potential compromise that is
beneficial to both sides can be lost. In Kansas, the classical natural resource problem of resource/recreation in a populated
area is presented as a case study. The state geological survey presented data on sand resources in the Kansas River and its
valley in northeast Kansas. That information was important to both recreation and dredging interests where the political problem
is a conflict of sand use as a construction material resource versus use of the alluvial river as an important recreation
area, especially for canoeing. However, when a reasonable compromise was near completion in the Kansas Legislature one side,
in a bold move to develop an advantage, ruined that potential for compromise.
Received: 12 May 1998 · Accepted: 6 July 1998 相似文献
4.
Four dates of Landsat Thematic Mapper data from 1993, April 9, July 30, August 15, and September 16, were used to assess temporal and spatial patterns of lake area and dimensions of suspended sediment concentration in Tuttle Creek Reservoir, Kansas. In 1993, excessive precipitation in the Big Blue River Basin, and throughout much of the Upper Middle West, led to widespread flooding. Rains produced substantial erosion, sediment movement down the stream network, and a runoff volume that filled Tuttle Creek Reservoir, a U.S. Army Corps of Engineers flood control structure. The April 9 data are from before the flood, the July 30 data are from the time of maximum pool size and use of the emergency spillway, and the August and September data document the declining pool sizes. Three separate analyses were performed on each of the four dates of Thematic Mapper data. One set of analyses involved applying an existing physical model that uses at-satellite reflectance for TM Band 3 to estimate variations in suspended sediment, turbidity, and Secchi depth throughout the reservoir. Maps of estimated parameters of water quality for the four individual dates were compared and analyzed to document spatial and temporal changes. The second research method involved unsupervised classification (ERDAS ISODATA algorithm) of the data from the Tuttle Creek Reservoir. Water areas were grouped into coherent classes for further spatial analysis using a two-step or layered classification procedure for each date. The third analysis used a GIS overlay technique to compare the area of the water surface for each of the four dates with the flood pool as marked on U.S.G.S. 7-1/2 minute quadrangles. Comparisons document the major change in lake area between April and July, the high levels of suspended sediment in mid-summer, and the decline in pool size and concentrations of suspended sediment by mid-September. The study illustrates the advantages of using remote sensing to assist in documenting a relatively short-term environmental hazard. This study also demonstrates the value of Landsat Thematic Mapper data for use in mapping geographic variations in water area and quality in conjunction with a major flood event. 相似文献
5.
Alan F. Arbogast 《Journal of Arid Environments》1996,34(4):403-414
Stratigraphic evidence and radiocarbon dating of sediments from the Great Bend Sand Prairie in Kansas indicates that significant deposits of aeolian sand have accumulated in the region during the late Holocene. Radiocarbon ages obtained from total humates in buried soils suggest that five periods of late-Holocene stability and soil formation are preserved in dune fields at approximately 2300, 1400, 1000, 700, 500 and 300 years B.P. Reactivation of aeolian sand in the past 1000 years has resulted in a variety of well defined, parabolic dunes. In general, events in the region correspond with established chronologies elsewhere on the Great Plains and in particular correlate well with dune fields in north-eastern Colorado. Overall, results indicate that the threshold of landscape stability on the Great Bend Sand Prairie can easily be crossed in the current climatic regime. 相似文献
6.
Moulds of Baculites sp. are common in the Smoky Hill Member but only five known specimens contain connecting rings that have been preserved because of mineralisation by carbonate apatite. Analysis of four of these specimens suggests that the connecting rings were originally composed of organic material and were mineralised during early diagenesis. Thin sections and scanning electron microscopy demonstrate that the connecting rings had a two-layered structure consisting of a thick siphuncular wall and a thin pellicle. 相似文献
7.
Historically land reserve programs have been used to reduce soil erosion. Slippage, which occurs when the number of acres enrolled in a reserve program is not met by an equivalent reduction of acreage in production, has limited reserve success, however. This study addresses the effect of slippage on conservation reserves in southwestern Kansas from 1988–1994. Slippage has varied considerably on both spatial and temporal bases. At one extreme the programs were 100% successful in removing land from production, but at the other extreme, slippage rendered reserve programs nearly useless. Overall, slippage in the study area has greatly reduced conservation reserve effectiveness. 相似文献
8.
CHRIS POST 《Geographical review》2009,99(2):186-207
ABSTRACT. Lawrence, Kansas, survived a tumultuous beginning. The young town endured attacks twice, in 1856 and 1863. The second raid, by the guerrilla William Quantrill's troop of more than 400 men, resulted in the deaths of 143 citizens. Lawrence serves as an example of how Americans memorialize unconventional warfare, targeted at citizens, in a material and permanent fashion on the landscape. Small and obscurely placed memorials fill the town, to the point that they have become ordinary. The memorialized landscapes of these tragedies thus display ambivalence toward the past and symbolically reject the loss of lives despite this era's high position in the literature and archival history of the town. Additionally, Lawrence has found alternative sources for its historical identity that do not reflect these tragedies but instead celebrate the city's pioneer establishment. In this article I use a set of methods for reading the memorialized landscape that includes archival and landscape analysis and uncovers the processes that have led to this town's understated and ambivalent memorialization and identity. 相似文献
9.
Western Kansas has an historical identification with cattle, with a focus on cattle ranching and more specifically since the 1950s, beef-cattle feedlots. Since the mid-1990s large dairy operations have moved into southwestern Kansas. Today more than twenty large dairies house more than 70,000 milk cows. These operate as confined feeding operations similar to beef-cattle feedlots. Regional advantages for the dairy industry include affordable land with wide-open space, local residents' cattle- and dairy-friendly attitudes, and other factors. Regional promoters have actively recruited dairies, and a dairy-business support system has emerged. The prospects for continued expansion of dairies in southwestern Kansas are unclear; despite the locational advantages and the possibility that the industry may continue to relocate here, as did the cattle-feeding industry several decades ago, further moves into the area may depend on continued resources availability and additional infrastructure development. 相似文献
10.
Sediment storage and severity of contamination in a shallow reservoir affected by historical lead and zinc mining 总被引：1，自引：0，他引：1
Kyle E. Juracek 《Environmental Geology》2008,54(7):1447-1463
A combination of sediment-thickness measurement and bottom-sediment coring was used to investigate sediment storage and severity
of contamination in Empire Lake (Kansas), a shallow reservoir affected by historical Pb and Zn mining. Cd, Pb, and Zn concentrations
in the contaminated bottom sediment typically exceeded baseline concentrations by at least an order of magnitude. Moreover,
the concentrations of Cd, Pb, and Zn typically far exceeded probable-effects guidelines, which represent the concentrations
above which toxic biological effects usually or frequently occur. Despite a pre-1954 decrease in sediment concentrations likely
related to the end of major mining activity upstream by about 1920, concentrations have remained relatively stable and persistently
greater than the probable-effects guidelines for at least the last 50 years. Cesium-137 evidence from sediment cores indicated
that most of the bottom sediment in the reservoir was deposited prior to 1954. Thus, the ability of the reservoir to store
the contaminated sediment has declined over time. Because of the limited storage capacity, Empire Lake likely is a net source
of contaminated sediment during high-inflow periods. The contaminated sediment that passes through, or originates from, Empire
Lake will be deposited in downstream environments likely as far as Grand Lake O’ the Cherokees (Oklahoma). 相似文献