Recent Vertical Movement of Land
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NU REG /CR-0874 RECENT VERTICAL MOVEMENT OF THE LAND SURFACE IN THE LAKE COUNTY UPLIFT AND REELFOOT LAKE BASIN AREAS, TENNESSEE, MISSOURI AND KENTUCKY R. G. Stearr.s Vanderbilt University y I f I t ; ) 9 ~ ' ' _ k\(,/;e . .!L J' '' : L:i- 3. 0 001 Prepared for U. S. Nuclear Regulatory Commission 7 0 0719 0 'dCf I IIOTICE This report was prepared as an account of work sponsored by an agency of the United States Government. fleither the United States Government nor any agency thereof, or any of their employees, makes any warranty, expressed or implied, or assumes any legal liability or resprnsibility for any third party's I use, or the results of such use, of any information, apparatus product or process disclosed in this report, or represents that its use by such third party would not infringe privately owned righ ts. I sg d u ') J v Available from National Technical Information Service Springfield, Virginia 22161 NU REG /CR-0874 R6,R A RECENT VERTICAL MOVEMENT OF THE LAND SURFACE IN THE LAKE COUNTY UPLIFT AND REELFOOT LAKE BASIN AREAS, TENNESSEE, MISSOURI AND KENTUCKY Prepared by R. G. Stearns Vanderbilt University Department of Geology Nashville, TN 37235 Manuscript Completed: Merch 1979 Date Published: June 1979 Prepared for Division of Reactor Safety Research Office of Nuclear Regulatory Research U. S. Nuclear Regulatory Commission Washington, D.C. 20555 NRC FIN No. B5960 3 } fj ij 0 2 i CONTENTS Abstract iv Introduction 1 Previous Studies 4 Background 4 Definitions and Descriptions of Tiptonville Dome, Reelfoot Lake Basin, and other Features 5 The Present Writer 's Use of Tiptonville Dome, Reelfoot Lake Rasin, and Lake County Uplift 9 Present Study 13 Acknowledgmente 14 Flood Maps 15 Uplift of Tiptonville Dome, Ridgely Ridge, and Bessie Ridge as Judged from Soil Maps and Topography 17 Topographic Envelopes 21 General 21 Detailed Topographic Envelope 22 Generalized Topographic Envelope 22 Modern Erosion of the Topographic Highs 26 Relation to Deeper Structure 29 Evidence from Gravity Anomaly Data 29 Evidence from Earthquake Epicenters 29 Conclusions 33 References Cited 37 ''jav i p C.vv [\ '!i ii ILLUSTRATIONS No. Page 1- Map showing location of the study area within the Mississippi Embayment . ..... 2 2- The study area showing the area of uplift and area of " Maxi- mum" uplift (stippled) as mapped by Fuller . ..... 3 3- Outline map showing the topographic features considered in this report that have or may have a tectonic origin ..... 11 4- Tiptonville Dome as part of a series of topographic highs, ' which are drawn as islands during a flood that of 1937 . 36 5- Soil map showing areas underlain by older soils ..... 18 6- Elevation of the areas shown on Figure 5 to be underlain by older soile . ..... 19 7- Detailed configuration of the alluvial plain of the Mississippi River in the study area . ..... 23 8- Generalized configuration of the entire width of the Eastern Lowlands of the alluvial plain c f the Mississippi River . ..... 24 9- Area occupied by channels of the Mississippi River since 1765, and the areas where lateral erosion has likely destroyed part of the Tiptonville Dome and Lewis Prairie . ..... 27 p (\bb 3 _, u iii No. Page 10- The flood islands as they may have been in 1812 . 28 11- Bouguer gravity anomaly map of the Tiptonville Dome, Ridgely Ridge and Reelfoot Lake area . 30 12- Earthquake epicenters in Lake County, Tennessee, and vicinity . 31 Tables 1- Soils in the study area that are described as having a "B" horizon . 20 2- Table of vertical movement, estimates and bases, for the various topographic features . 34 q e, n ; , )3 usu iv ABSTRACT Tiptonville Dome, an established tectonic uplift, is one in a 20 mile series of en echelon topographic highs , most or all of which are uplifts. These features are too high to have been flooded dur- ing the largest historic floods. During these floods they were temporary islands. From Lewis Prairie, at New Madrid in Missouri, five such topographical 3y high areas extend southward across the Mississippi River to Ridgely, Tennessee. Although separated now due to modern river erosion, they were nearly continuous in 1811. Contour trends reveal a squarish topographic bulge west of the " flood islands," the western corner of which is near Portageville, Misscuri. It may have been uplifted with, but less than, the " flood islands." This bulge and the topographic highs comprise the Lake County Uplift. Vertical movement is interpreted from variations in eleva- tion of the alluvial plain surface and old soils. Individual features, datums, and vertical movement estimated are as follows: TOPOGRAPHIC DATUM OF A DATUM OF ___ FEATURE LARGE FLOOD REELFOOT LAKE Ridgely Ridge Up 5-15 feet Up 20-25 feet Tiptonville Dome Up 10-20 feet Up 35-40 feet Bessie & Washpan Ridges Up 0-10 feet Up 15-20 feet Lewis Prairie Up 5 feet Up 5 feet Reelfoot Lake Basin -- --- ------ Portageville Bulge ----- Up 0- 5 feet Ridgely Ridge and Tiptonville Dome in Tennessee correlate with positive gravity anomalies, and small earthquakes are concentrated beneath or near them. Thus these topographic features may be sur- face manifestations of deep-scated tectonic movements that contpgue Ob' }'70'" today. 1 INTRODUCTION Stratigraphically defined structural datum planes, from which historic and late pre-historic vertical movements of tectonic origin can be measured, are obscure or very irregular in the New Madrid earthquake region of southeast Missouri and northwest Tennessee. Unconformities such as that at the base of the high level continental deposits of Pleistocene and Pliocene (?) age and the base of the Mississippi River alluvium of Late Pleistocene and Recent age are irregular and hundreds of thousands or more years old. These provide poor data from which to recognize recent structural dis- placements. Possibly a more senitive datum is the -elatively even Holocene surface of the Mississippi River alluvial plain. A coincidence between the shape of this surface, and several other mapped parameters including distribution of soils with a B-horizon. Bouguer gravity anomaly, and distribution of earthquakes will be shown. F.gure 1 shows the general location of the area referred to in t-his report. Figure 2 shows the same area as n apped by Fuller (1912, Plate 1). 7 l'~l\O J;Gu veu 2 91* 90* 89* 88* MO ILL g t .- ' 5 M .. g9B 7 . - s /J v 37' - f d' ,4 k % 9 13 - +N + NEW / a ,_ -MADRIO i s q ' ,' O ~' KY MO _ _ _ / _ - _ - __ , ARK s EELFOOT TENN - ' ' ,',4 LAKE (7 7 | 4 ' T,1 TOtiVILL E , ' % / x : . ..* 4 N ' / MO e / _ 36' + s g ARK q' 7 ___[C o v d s.. L 6 * ~~ - ~s f N i e% ., ' 4 4 * * \, .% e MEMPHIS / TENN __ __ -- - -- -- - { ARK -'f(f 35* MISS LA O 50 MILES Figure 1- Map showing location of the study area within the Mississippi Embayment. The Tiptonville Dome limits of Fuller are shown by the dotted line around Tiptonville, Tennessee. ;m, n '.) ae 330 m 3 NEW MADRID N KY HICK- 1 i MAN MO / ' KY KY __ (/ 2- ~~ ~/ ~ TENN ' $/ , s = , y '"" PORTAGE u.f '. 6 VIL L E .- g , >h o (o so} - '. ' 4 ~/ , 4 E ~l r3 _ h J I P- - Qh TON - . - '.VIL.LE.. y W| O H / T MO R I D GE LY ' O & ,Of . O TENN g / ,2 %/ ,' L A K E CO. g _ _ C ARUT H- 0 5 10 MILES ' ' ' ERSVILLE 2 Figure 2- The study area showing the area of uplift and the area of " maximum" uplift (stippled) as mapped by Fuller (1912, redrawn from a pa rt of his Plate 1). Compare this with Figure 3. , j,jO C b, 4 PREVIOUS STUDIES , Background 4 Vertical movements have been inferred for portions of the region in the vicin.ty of Lake County, Tennessee, by Usher (1837), McGee (1892), Fuller (1912), and Fisk (1944). Fuller mapped the limits of uplift and an area of greater uplift of the Tiptonville Dome, which he named (Figure 3). Glenn (1933) suggested that the Reel- foot Lake sunken lands were the result of compaction during the earthquakes of 1811-12, rather than downfaulting, but Fisk (1944) asserted that a fault separates the Tiptonville ome and Reelfoot Lake sunken land, and he supported this interpretation by drill records as well as river elevation data. Krinitzsky (1950), dis- cussed criteria for recognizing faults; one of his criteria was irregularities that appear on profiles of the land surface. Later Saucier (1970' suggested a physiographic origin for the St. Francis e' Ink land. Past work leaves open the possibility of much vertical tectonic movement, but alternative explanations are offered. This present paper, though not concerned with faulting versus " bulging" uses lateral changes in the land surface elevation and gradients on maps to infer likely tectonic uplift and downsinking patterns. pI ' n_ v ,f) J V 5 Definition and Descriptions of Tiptonville Dome, Reelfoot Lake Basin, and Other Features The Tiptonville Dome and Reelfoot Lake Basin were first described in the geological literature ay Usher (1837) who had seen them several years before writing his report and had repro- duced them from memory. He noted that the entire left (Tennessee) bank of the river was uplifted from New Madrid south to the mouth of the Obion River, or from about latitude 36 35' to latitude 36 . The uplift was said to be "only a few feet," but yet it obstructed the mouth of Reelfoot Creek and the Obion River. He also stated that "this obstruction formed several lakes along back of this . It is quite probable that the land there was depressed in some degree in order to form these lakes." Usher was explic_e that the uplift is on the Tennessee side and said that on the Missouri side New Madrid sank.