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J.W. Allingham

Publications and source records attributed to J.W. Allingham.

3 recordsLinked to original sources

Reclamation of mined lands in the western coal region

In 1978, a group of scientists from several Federal agencies examined reclamation work at 22 coal mines in seven western States. The results of these examinations were not used to derive quantitative predictions of the outcome of reclamation work but rather to determine the general requirements for revegetation success. Locally, reclamation efforts are affected by climate, especially precipitation; the landform of the restored surface; the nature of the overburden material; the nature of the surface soil; and the natural ecological system. The goals of reclamation efforts are now broader than ever. Regulations call not only for reducing the steepness of the final surface and establishing a cover of mostly perennial native vegetation, but for restoring the land for specific land uses, achieving diversity both in types of plants and in number of species, and reintroduction of biological and ecological processes. If specific sites are monitored over a long enough period of time, quantitative predictions of success for individual mines may be possible, and such predictions can be included in environmental impact statements to help in the decision-making process. The results of this study indicate that current reclamation objectives can be met when the reclamation effort is designed on the basis of site-specific needs and when existing technology is used.

Circular

Low-amplitude aeromagnetic anomalies in Southeastern Missouri

This study shows that aeromagnetic anomalies of less than 200 gammas are associated with topographic relief of exposed Precambrian granitic and volcanic rocks of the St. François Mountains. Anomalies resulting from hills coarsely crystalline granite are as high as 100 gammas in amplitude , whereas anomalies over comparable hills of fine-grained rocks, such as granophyre or devitrified volcanic rock, are as much as 200 gammas. Anomalies caused by normal faulting or shearing of igneous rocks have amplitudes of less than 100 gammas; they are observed best in profile. These anomalies are superposed on larger magnetic features related to pendants of volcanic rock in the roof of a granite batholith and are distinguished from large lateral variations in magnetic intensity by their low amplitude and small areal extent. Analyses of the compound anomalies yielded the subsurface configuration of isolated roof pendants of resistant extrusive rock in some areas. As many of these pendants have negligible remanent magnetization, induction theory was used in the analyses. Application of these results to the lead-mining areas shows that aeromagnetic patterns of low amplitude can guide mineral exploration in the region flanking the Ozark uplift, where isolated, buried hills of Precambrian igneous rocks controlled the development of some lead-bearing sedimentary structures in the overlying Cambrian carbonate strata.

Missouri