Preliminary Notes on the Carboniferous Flora of Nebraska Roy V
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University of Nebraska - Lincoln DigitalCommons@University of Nebraska - Lincoln Conservation and Survey Division Natural Resources, School of 1910 Preliminary Notes on the Carboniferous Flora of Nebraska Roy V. Pepperberg Follow this and additional works at: http://digitalcommons.unl.edu/conservationsurvey Part of the Geology Commons, Geomorphology Commons, Hydrology Commons, Paleontology Commons, Sedimentology Commons, Soil Science Commons, and the Stratigraphy Commons This Article is brought to you for free and open access by the Natural Resources, School of at DigitalCommons@University of Nebraska - Lincoln. It has been accepted for inclusion in Conservation and Survey Division by an authorized administrator of DigitalCommons@University of Nebraska - Lincoln. 20 NEBRASKA GEOLOGICAL SURVEY ERWIN HINCKLEY BARBOUR, State Geologist VOLUME 3 PART 11 Preliminary Notes on the Carboniferous Flora of Nebraska By ROY v. PEPPERBERG Preliminary Notes on the Carboniferous Flora of Nebraska. BY ROY V. PEPPERBERG. About the middle of July, 1907, while engaged by the Nebraska City Commercial Club in examining the geology of Nebraska City and vicinity, the writer was called b the farm of Mr. C. B. James to look at a bed of what was sup posed to be fire clay. rfhis proved to be a Carboniferous deposit of stratified micaceous sandstone, interstrntified with a fine compact shale, both of which are yellow in color and very fragile when wet. The. exposure is about a mile and one-half northeast of Nebraska City and' within twenty feet of the Missouri River. A small creek draining into the river has cut through fifty feet of soil and loess into the underlying shale above described, the thickness of which has not yet been determined, extending ns it does below the Missouri water level, (high water). ,Vhile examining this bed and taking samples of the same, the writer was much surprised to discover many leaf impressions in the shale. Numerous specimens were collected and brought to the laboratory for study. The work done up to the present time is preliminary only, and before the Carboniferous flora of this state can be definitely known it will be necessary to make a careful EDITORIAL NOTE: After completing his stUdies, and after fulfilling all requirements for the Masters Degree, the writer of this paper submitted the following two-part theSis: 1. Coal in Nebraska, (Nebraska Geological Survey, part 10. Vol. 3). 2. Preliminary Notes on the Carboniferous Flora of Nebraska (the present paper). 314 NEBRASKA GEOLOGICAL SURVEY search throughout the Carboniferous region in all of the southeastern counties of Nebraska. Since discovering the bed of Carboniferous leaves at Nebraska City, the writer has made two trips to the local ity, collecting specimens from Nebraska City and Peru. The flora at Peru was observed by Meek in 1867 and recent ly by Mr. N. A. Bengtson, Adjunct Professor of Geography, the University of Nebraska. It occurs in a formation similar to, though more arenaceous than the one at Nebras ka City. It is best described by Meek as follows: 1 , 'Less than a quarter of a mile below the village of Peru there is an abrupt exposure of yellowish and light-gray, soft, somewhat micaceous sandstone, with large, round and compressed concretions of arenaceous matter, of consider able hardness. Some of these concretions are oval in form. There are also very curious irregulady and obliquely ar ranged seams Dnd isolated masses of dark bluish shaly matter and clay. These appear as if the sandstone had been irregularly erroded in places during its deposition, and the shaly matter deposited in the depressions and then more sand upon it again. Fragments of coal were also seen imbedded in the sandstone, along with stems of Calamites, and broken up leaves of ferns. The sandstone can scarcely be said to be stratified, but appears massive with the ex ception of some oblique marks of deposition, and the in tercalated seams of shaly matter. The latter are not con tinuous for any distance, but often end very abruptly, or in other cases become much attentuated, and again swell out to a foot or so in thickness. They do not appear to conform to the bedding of the sandstone but cut obliquely across it at various angles, and yet their laminated structure, and fragment of plants, show they were deposited in water. This exposure of sandstone rises abruptly from the edge of the river at high water, to an elevation of about 60 to 65 feet. Its position is doubtless nearly the snme as the lower 1. Mook-Kan. D. C. Be. XVI, p. 72 CARBONIFEROUS FLORA 315 part of Otoe City (now Minersville) section, though it is more arenaceous here, and perhaps thicker." It is very difficult to collect leaf impressions from this exposure except from weathered fragments, which cleave readily. The specimens found here are of an entirely dif ferent character from those collected from Nebraska City, being composed largely of Calamariae, and stumps of some large tree which is as yet unidentified, but probably a con ifer. Only one small fragment of a Neuropteris pinnule has been found so far, but it is very probable that others will appear when extended collecting is done in this bed. In Nebraska the leaf-bearing bed has not been traced but it probably extends through the Carboniferous counties, that is the extreme eastern part of the state. The only men tion we find of its presence, besides the above, are such re ferences as: 1 "Fragments of plants are found in a yellow, micaceous sandstone at Nebraska City" again 2 "Two miles .above Rulo fossil ferns are found in a bluish and drab arenaceous clay." Both of these places are in the Carboni ferons region and the" plants" and" ferns" referred to are undoubtedly Carboniferous flora. It is possible that the "fragments of plants" Meek found at Nebraska City were from the same formation as those of recent discovery, however the sections do not agree for he records them as being found sixty-three feet above the Missouri river (high water mark), while the present bed occurs only a few feet above the same. Meek's section was taken at least three miles south of the James farm and since the dipis toward the southeast it is improbable that the. bed sixty-three feet above the Missouri river in this section should be present at all three miles above, for the entire section is not more than fifty feet above the river. This shows that if Meek's section is correct there are two dis tinct strata in which Carboniferous plants have been found 1. U. S. G. S. of Nebraska 1867, p. 109. 2. Meek-Kan. D. C. Sc. XVI, p. 74. 316 NEBRASKA. GEOLOGICAL SURVEY at Nebraska City,l however the writer saw no evidence of plants in the bed to which Meek refers although a careful study was made of the beds outcropping between Nebraska City and Minersville (Otoe City.) Meek's Rulo bed is perhaps in the same horizon as the' Nebraska City and Peru beds, for indications confirm the supposed dip in that direction, first pointed out by Meek and Hayden and since confirmed by all who have worked over the same ground. The mention given the Carboniferous flora in 1867 being the only reference the writer has found upon this flora in Nebraska, is deemed important enough to give briefly the sections Meek made along the Missouri River in which he found this flora: SECTION OF 11HE BEDS Nr THE NEBRASKA CITY LANDING." Nature of Strata. Thickness Ft. In. E. Loess or bluff deposit, consisting of fine light grayish pulverent silicious and more or less calcareous clay or marl, without distinct marks of stratification; rising back to a height of 80 to. .. 90 0' D. Yellowish-gray micaceous, soft sandstone, laminated or in thin ripple-marked layers, ex cepting 12 to 15 inches of the lower part, which IS sometimes hard and compact, WITH FRAGMENTS OF PLANTS. .. 10 0' C. Drab, ash, and lead-colored, and redish brown clays, with, near the middle a 9 or lO-inch hard bluish-gray argillo-calcareous layer, weathering to a rusty color ................. 39 0 1. It is possible that there is a local dip to the North although, It Is not evident. 2. U. S. G. S. Nebraska 1867, Meek and Hayden, p. 1.01-2. CARBONIFEROUS FLORA 317 B. Several beds of hard, light-grayish, and yel lowish limestones in layers of from 5 to 20 inches in thickness, with soft, marly clay seams and partings. .. 12 0 A. a. Lead-gray and greenish clay, 4 feet: b. Reddish-brown ferruginous, slightly gritty, indurated clay, 4 feet exposed above high water mark ............................... 8 0 Total below drift .................... 69 SECTIONS OF THE VARIOUS BEDS EXPOSED AT BROWNVILLE.l No. Nature of Strata. Thickness Ft. In. 14. Loess rising back with the slope from 30 or 40 to ...... , ..................... '" ....... 100 0 13. Dark-bluish, very fine unctuous clay, becom ing nearly black below, and weathering to a drab color ............................... 2 0 12. Yellowish-gray granular or sub-oolitic lime stone; massive, but showing a disposition to divide into two layers. 3 0 11. Unexposed...... ...... " ............ , 10 0 10. 'Whitish, soft argillaceous limestone; 6 to 8 inches thick .............................. 0 8 9. Red, purple, and greenish clays. .. 10 0 8.·Whitish and yellowish Impure limestone; rather massive. 3 0 7. Purple clay .............................. 1 0 6. Soft, whitish limestone. 6 0 5. Bluish clay... ................. .......... 5 6 4. Black shale and seams of impure coal, with IMPRESSIONS OF FERN LEAVES. 1 0 .3. Blue clay, with fragments of coal and Iron pyrites. .. 20 0 1. U. S. G.