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D.M. Moore

Publications and source records attributed to D.M. Moore.

6 recordsLinked to original sources
USGS2024

Ordovician and Pennsylvanian berthierine-bearing flint clays

We report here the first occurrence of berthierine-bearing flint clays, one Ordovician and one Pennsylvanian in age. They are characterized by a berthierine-kaolinite-boehmite (bkb) assemblage. The Pennsylvanian flint clay from northeastern Kentucky is more typical in that it occurs in association with coal measures. The Ordovician occurrence from northwestern Illinois is the oldest flint clay of which we are aware. Because it is Ordovician, it formed before the evolution of terrestrial vascular plants. All previous reports of flint clays point to a genetic connection between flint-clay formation and the growth and decay of plants (Bohor and Triplehorn, 1993). Except for the high berthierine content and greenish color, the physical properties of this flint clay are similar to those of other kaolinitic flint clays. Some samples of the Ordovician flint clay are nearly pure berthierine.

Clays and Clay Minerals↗
USGS2005

Geochemical transformations and modeling of two deep-well injected hazardous wastes

Two liquid hazardous wastes (an alkaline brine-like solution and a dilute acidic waste) were mixed with finely ground rock samples of three injection-related lithologies (sandstone, dolomite, and siltstone) for 155 to 230 days at 325°K-10.8 MPa. The pH and inorganic chemical composition of the alkaline waste were not significantly altered by any of the rock samples after 230 days of mixing. The acidic waste was neutralized as a consequence of carbonate dissolution, ion exchange, or clay-mineral dissolution, and hence was transformed into a nonhazardous waste.

Groundwater↗
USGS2002

Mineralogical Approaches to Sourcing Pipes and Figurines from the Eastern Woodlands, U.S.A.

Provenance studies of stone artifacts often rely heavily upon chemical techniques such as neutron activation analysis. However, stone specimens with very similar chemical composition can have different mineralogies (distinctive crystalline structures as well as variations within the same mineral) that are not revealed by multielemental techniques. Because mineralogical techniques are often cheap and usually nondestructive, beginning with mineralogy allows the researcher to gain valuable information and then to be selective about how many samples are submitted for expensive and somewhat destructive chemical analysis, thus conserving both valuable samples and funds. Our University of Illinois team of archaeologists and geologists employs Portable Infrared Mineral Analyzer (PIMA) spectroscopy, X-ray diffraction (XRD), and Sequential acid dissolution/XRD/Inductively coupled plasma (SAD-XRD-ICP) analyses. Two case studies of Hopewellian pipes and Mississippian figurines illustrate this mineralogical approach. The results for both studies identify sources relatively close to the sites where the artifacts were recovered: Sterling, Illinois (rather than Ohio) for the (Hopewell) pipes and Missouri (rather than Arkansas or Oklahoma) for the Cahokia figurines. ?? 2002 Wiley Periodicals, Inc.

Geoarchaeology - An International Journal↗
USGS2000

Diagenesis of the Purington Shale in the Illinois Basin and implications for the diagenetic state of sedimentary rocks of shallow Paleozoic basins

The clay minerals, micas, and feldspars of the Pennsylvanian-age Purington Shale have been more diagenetically active than generally recognized. They have undergone diagenetic changes comparable to those of Cenozoic and Mesozoic sedimentary rocks buried three to four times as deeply and heated to approximately twice the temperature. The Purington Shale on the Western Shelf of the Illinois Basin has experienced maximum burial of ???1.0 km and was never heated to more than 60??C, except for a very brief time at about 80??C. The illite/smectite (I/S) of the Purington Shale has ???90% illite. The chemical compositions of the feldspar assemblage in the 0.09-0.063-mm fraction differ from most modern detrital suites of feldspars but are similar to diagenetic sequences described by others from much greater burial depths and are extensively, but not completely, albitized. The simplest interpretation of the apparently advanced stage of diagenesis is that the diagenetic processes have been operating at less pressure and lower temperature but for a longer time; an example of low-temperature, time-dependent diagenesis. By similar reasoning, the apparently anomalously advanced maturity of all of the sedimentary rocks in the relatively shallow Illinois Basin is explained. This generalization should be considered for all shallow Paleozoic basins and should influence (1) exploration for petroleum, (2) use of modal and chemical analyses for determining provenance, and (3) use of chemical composition of shales as proxy for crustal evolution.

Journal of Geology↗
USGS1997

Tapir ( Tapirus ) enteroliths

Enterolith fragments from two tapir species and horses were subjected to x-ray diffraction analysis. Tapir enteroliths were formed as layers of mineral deposited around a foreign nidus. The structure was similar to that of equine enteroliths except that tapir enteroliths lacked a central region of radially symmetrical coarse crystals. The enteroliths from tapirs were composed primarily of vivianite [Fe 3 (PO 4 ) 2 · 8H 2 O] and newberyite [MgH(PO 4 ) · 3H 2 O], instead of the struvite [Mg(NH 4 )(PO 4 ) · 6H 2 O] of enteroliths from horses. The reason for this difference is not known. Based on the chemistry of these mineral precipitates and information from other species, it was concluded that dietary manipulation to maximize carbohydrate fermentation and minimize protein fermentation in the large intestine may help prevent enterolithiasis in tapirs.

Illinois, Minnesota↗