The Midwestern Taxonomic Method as an Aid to Archaeological Culture Study

1939 ◽  
Vol 4 (4) ◽  
pp. 301-313 ◽  
Author(s):  
W. C. McKern
Keyword(s):  
Delayed Response ◽  
Mississippi Valley ◽  
Northern Plains ◽  
Culture Study ◽  
Definition Of ◽  
Valley Area

In delayed response to a certain demand for a published statement covering the archaeological taxonomic method introduced in the northern Mississippi Valley area a few years ago and now tentatively employed in this, the northern Plains, and the Northeastern areas, it seems advisable to briefly set forth in this journal the essential framework for this method, and to include a revision of previously outlined but unpublished discussions relating thereto, in addition to a brief definition of certain problems involved in its application.

scholarly journals A Proposed Revision to the Definition of “Derecho”

2016 ◽  
Vol 97 (6) ◽  
pp. 935-949 ◽  
Author(s):  
Stephen F. Corfidi ◽  
Michael C. Coniglio ◽  
Ariel E. Cohen ◽  
Corey M. Mead
Keyword(s):  
Initial Step ◽  
The United States ◽  
Early Years ◽  
Mississippi Valley ◽  
Physical Processes ◽  
Convective Systems ◽  
Convective Structures ◽  
Physically Based ◽  
Wind Events ◽  
Definition Of

Abstract The word “derecho” was first used by Gustavus Hinrichs in 1888 to distinguish the widespread damaging windstorms that occurred on occasion over the mid–Mississippi Valley region of the United States from damaging winds associated with tornadoes. The term soon fell into disuse, however, and did not appear in the literature until Robert Johns and William Hirt resurrected it in the mid-1980s. While the present definition of derecho served well during the early years of the term’s reintroduction to the meteorological community, it has several shortcomings. These have become more apparent in recent years as various studies shed light on the physical processes responsible for the production of widespread damaging winds. In particular, the current definition’s emphasis on the coverage of storm reports at the expense of identifying the convective structures and physical processes deemed responsible for the reports has led to the term being applied to wind events beyond those for which it originally was intended. The revised definition of a derecho proposed herein is intended to focus more specifically on those types of windstorms that are the most damaging and potentially life threatening because of their intensity, sustenance, and degree of organization. The proposal is not intended to be final or all encompassing, but rather an initial step toward ultimately realizing a more complete physically based taxonomy that also addresses other forms of damaging-wind-producing convective systems.

Wheat-Soybean Double-Crop Systems on Clay Soil in the Mississippi Valley Area

jpa ◽  
1988 ◽  
Vol 1 (2) ◽  
pp. 166-171 ◽  
Author(s):  
Richard A. Wesley ◽  
F. T. Cooke
Keyword(s):  
Clay Soil ◽  
Mississippi Valley ◽  
Valley Area

Middle OrdovicianLophospira(Archaeogastropoda) from the Upper Mississippi Valley

1987 ◽  
Vol 61 (4) ◽  
pp. 700-723 ◽  
Author(s):  
Jane Evans Tofel ◽  
Peter W. Bretsky
Keyword(s):  
Marine Invertebrate ◽  
Eastern North America ◽  
Mississippi Valley ◽  
Invertebrate Fauna ◽  
Middle Ordovician ◽  
Fine Grained ◽  
Physical Energy ◽  
Major Alteration ◽  
Definition Of ◽  
Benthic Marine Invertebrate

A detailed morphological study of over 2,500 Middle Ordovician (Black Riveran) lophospirid archaeogastropods from the lower half of the Platteville Formation (Pecatonica Member and Mifflin Submember of the McGregor Member), principally as it is exposed in southern Wisconsin, has permitted the definition of five species ofLophospira. Lophospira perangulata(Hall),L. milleri(Hall),L. serrulata(Salter),L. helicteres(Salter), andL. delicata(n. sp.) are preserved throughout a three-meter interval of fine-grained, heavily bioturbated carbonates, now dolomitized. Deposition took place on a broad, shallow tropical shelf, which was characterized by low rates of deposition and low physical energy. The sampled interval represents about 500,000 years. The benthic marine invertebrate fauna is well preserved, diverse, and characteristic of an environment of normal marine salinity.Of the fiveLophospiraspecies, only one,L. perangulata, has been positively identified in older strata (late Whiterockian, eastern North America). The other four species were endemic to the interior seas, and apparently at least two of these,L. serrulataandL. helicteres, did not survive into post-Platteville (post-Black Riveran) environments. Changes in the proportions of lophospirid species from the Pecatonica into the Mifflin strata probably reflect subtle changes in the distribution of carbonate shelf habitats but no major alteration in the kinds of habitats available for colonization.

scholarly journals Earthquake magnitude, intensity, energy, and acceleration*

1942 ◽  
Vol 32 (3) ◽  
pp. 163-191
Author(s):  
B. Gutenberg ◽  
C. F. Richter
Keyword(s):  
Wave Train ◽  
Empirical Relation ◽  
The United States ◽  
Earthquake Magnitude ◽  
Mississippi Valley ◽  
Maximum Acceleration ◽  
Hypocentral Distance ◽  
Accurate Definition ◽  
Physical Elements ◽  
Definition Of

Summary The paper investigates the principal physical elements of earthquakes: the magnitude M, energy E, intensity I, acceleration a, and their relation to the depth h and radius of perceptibility r. (r2 + h2 = R2. Subscript zero (0) refers to the epicenter.) Equations log ⁡ a = I 3 − 1 2 and A D 2 T 2 = constant (A = ground amplitude, T = period, D = hypocentral distance for a given shock) are established empirically for California shocks. Equation (9) holds very generally, and offers a basis for a more accurate definition of I, like that suggested by Cancani. Equation (4) is here used very generally at short distances; but it is approximate only, may differ regionally, and bridges over the probably discontinuous transition of the maximum acceleration from S̄ to some other transverse wave, with increasing distance. However, consequences derived from (4) nowhere conflict seriously with observation. The instrumental earthquake-magnitude scale has been extended to cover short distances. The results enter into an empirical relation M = 2.2 + 1.8 log ⁡ a 0 from which and (9) follows M = 1.3 + 0.6 I 0 These two equations are established and verified for the California region; they should also hold in other regions of similar structure for earthquakes originating at about the same depth (which is roughly 18 km.). The simplest possible assumptions (constant velocity, negligible absorption, sinusoidal waves) lead to the general equation log ⁡ E = 14.9 + 2 log ⁡ h + log ⁡ t 0 + 2 log ⁡ T 0 + 2 log ⁡ a 0 (t0 = duration, T0 = period, of sinusoidal wave train at the epicenter). Equations (27), (9), and (4) give the generally applicable results a 0 h 2 = a D 2 = a r R 2 I 1 − I 2 = 6 log ⁡ D 2 D 1 I 0 − 1.5 = 6 log ⁡ R h ar, the minimum perceptible acceleration, is approximately 1 gal. For shocks at the usual depth in California log ⁡ E = 11.3 + 1.8 M For other depths, and probably for other regions, log ⁡ E = 9.5 + 3.2 log ⁡ h + 1.1 I 0 log ⁡ E = 11.1 + 6.4 log ⁡ R − 3.2 log ⁡ h A summary of the physical elements for shocks in California is given in table 10. Equation (13) is used to calculate apparent depths for earthquakes in the United States and Europe. The results tend to confirm the relatively shallow origin of shocks on the Pacific Coast compared with those occurring elsewhere, particularly under the Canadian Shield, the central Mississippi Valley, and the southern Appalachians.

5 Summary Definition of the Issaquena Phase

1964 ◽  
Vol 18 ◽  
pp. 108-111
Author(s):  
Robert E. Greengo
Keyword(s):  
The Other ◽  
Mississippi Valley ◽  
The South ◽  
Lower Mississippi Valley ◽  
Yazoo Basin ◽  
Definition Of

The Issaquena phase is postulated as a discrete culture unit identified at four sites in the southern part of the Yazoo Basin in the Lower Mississippi Valley. The primary criteria distinguishing this culture unit are a number of pottery types within a Lower Mississippi Valley ceramic tradition. The four marker types are: Manny Stamped, characterized by medium-sized open bowls with thickened rims, and decorated by zoned, dentate rocker-stamping outlined by deep U-shaped incisions on the exterior; Yokena Incised, with similar forms, but decorated by bold designs without background roughening; Troyville Stamped, again with the basic open bowls, but decorated with zoned non-dentate rocker-stamping; and Churupa Punctated, a type closely related to the other three but decorated by zones of hemiconical punctations outlined by the above-described type of incised line. These ceramic groups have prototypes in the preceding Marksville phase, apparently centered somewhat to the south in the Lower Mississippi Valley. It may be noted here that all of the pottery of the Issaquena phase has come from occupation deposits and thus may be construed as utility ware.

Biometry of the Late Cambrian trilobite genus Dikelocephalus and its implications for trilobite systematics

1994 ◽  
Vol 68 (3) ◽  
pp. 492-517 ◽  
Author(s):  
Conrad C. Labandeira ◽  
Nigel C. Hughes
Keyword(s):  
Morphological Variation ◽  
Taxonomic Status ◽  
Taxonomic Diversity ◽  
Species Level ◽  
Mississippi Valley ◽  
Late Cambrian ◽  
Morphometric Analyses ◽  
Cambrian Trilobite ◽  
Multiple Species ◽  
Definition Of

It has been proposed previously that the northern Mississippi Valley Sunwaptan trilobite genus Dikelocephalus comprises 26 species. Morphometric analyses demonstrate that many of the criteria that had been used to define species of Dikelocephalus are invalid and additional analysis of biostratigraphically and biogeographically constrained collections is necessary before the taxonomic status of Dikelocephalus can be fully resolved. Our results indicate that infrageneric morphological variation in Dikelocephalus is continuous and lacks gaps that could be the basis for establishing multiple species. Many of the characters shown to be taxonomically insignificant in Dikelocephalus are also widely used in the definition of other trilobite taxa. This suggests that the species-level taxonomy of many trilobites may be substantially oversplit. Recognition of widespread oversplitting will have important consequences for biostratigraphic zonations, paleogeographic distributions, and estimates of taxonomic diversity.

Episodic potassic diagenesis of Ordovician tuffs in the Mississippi Valley area

Geology ◽  
1988 ◽  
Vol 16 (8) ◽  
pp. 743 ◽  
Author(s):  
R.L. Hay ◽  
Mingchou Lee ◽  
Dennis R. Kolata ◽  
J. C. Matthews ◽  
J. P. Morton
Keyword(s):  
Mississippi Valley ◽  
Valley Area
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