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Baylor Geological Studies BAYLORGEOLOGICA L STUDIES PAUL N. DOLLIVER Creative thinking is more important than elaborate FRANK PH.D. PROFESSOR OF GEOLOGY BAYLOR UNIVERSITY 1929-1934 Objectives of Geological Training at Baylor The training of a geologist in a university covers but a few years; his education continues throughout his active life. The purposes of train­ ing geologists at Baylor University are to provide a sound basis of understanding and to foster a truly geological point of view, both of which are essential for continued professional growth. The staff considers geology to be unique among sciences since it is primarily a field science. All geologic research in­ cluding that done in laboratories must be firmly supported by field observations. The student is encouraged to develop an inquiring ob­ jective attitude and to examine critically all geological concepts and principles. The development of a mature and professional attitude toward geology and geological research is a principal concern of the department. Frontis. Sunset over the Canadian River from near the abandoned settlement of Old Tascosa, Texas. The rampart-like cliffs on the horizon first inspired the name "Llano Estacado" (Palisaded Plain) among Coronado's men. THE BAYLOR UNIVERSITY PRESS WACO, TEXAS BAYLOR GEOLOGICAL STUDIES BULLETIN NO. 42 Cenozoic Evolution of the Canadian River Basin Paul N. DoUiver BAYLOR UNIVERSITY Department of Geology Waco, Texas Spring 1984 Baylor Geological Studies EDITORIAL STAFF Jean M. Spencer Jenness, M.S., Editor environmental and medical geology O. T. Ph.D., Advisor, Cartographic Editor what have you Peter M. Allen, Ph.D. urban and environmental geology, hydrology Harold H. Beaver, Ph.D. stratigraphy, petroleum geology Rena Bonem, Ph.D. paleontology, paleoecology William Brown, M.S. structural tectonics Robert C. Grayson, Ph.D. stratigraphy, conodont biostratigraphy and sedimentary petrology Don M. Greene, Ph.D. physical geography, climatology, earth sciences Don F. Parker, Ph.D. igneous geology, volcanology, mineralogy, petrology Ker Thomson, D.Sc. W. M. Keck Foundation Chair in Geophysics Joe C. Yelderman, Jr., Ph.D. hydrogeology STUDENT EDITORIAL STAFF Jonathan D. Peterson, Cartographer The Baylor Geological Studies Bulletin is published by the Department of Geology at Baylor University. The Bulletin is specifically dedicated to the dissemination of geologic knowledge for the benefit of the people of Texas. The is designed to present the results of both pure and applied research which will ultimately be impor­ tant in the economic and cultural growth of the State. ISSN 0005-7266 Additional copies of this bulletin can be obtained from the Department of Geology, Baylor University, Waco, Texas 76798. $1.05 postpaid. CONTENTS Page Abstract Introduction 6 The Present Day Canadian River Basin History of the Canadian Basin Region 20 The Ogallala Erosion Cycle 22 The Pleistocene Canadian River Basin 36 Pleistocene Drainage Evolution of the Montane Border of the Canadian Basin 44 Pleistocene Evolution of the Plains of the Canadian Basin 57 Conclusions 77 Appendix A: Sample Localities 80 Appendix B: Literature Localities 86 Appendix C: Lithologic Percentages of Representative Samples 87 References 88 Index 94 ILLUSTRATIONS FIGURE 1. The Canadian River basin 2. Routes of early scientific parties, western Canadian basin 10 3. Diagrammatic cross sections, Sangre de Cristo Mts. and western Raton basin 4. Major tectonic elements within and surrounding the Canadian River basin 12 5. Creston east of Mora, New Mexico 6. Cimmaron canyon 7. "Abandoned valley" of Coyote Creek 8. map, Canadian River basin 48 9. West-facing Ogallala escarpment near Mills, New Mexico 14 10. Entrenchment of Canadian River near Sabinoso, New Mexico 14 Inner valley of Canadian River near Lake Meredith, Texas 12. Mean annual precipitation map, Canadian River basin 16 Mean Annual runoff map, Canadian River basin Effect of temperature on mean annual runoff and mean annual precipitation Variation of annual sediment yield with 18 Effect of temperature on mean annual sediment yield and mean annual precipitation 18 17. Effect of temperature on mean annual sediment concentration and mean annual precipitation geographic aspects of drainage history 19. Southern Rocky Mts, postulated extent of middle Tertiary volcanic field 22 20. Probable impact of climatic change on hydrology and deposition, middle Oligocene fluvial systems 22 21. Percentage and composition of quartzose constitutents in Ogallala and probable Ogallala gravels 23 22. Montane Ogallala source terrain and inferred foci of Ogallala sediment dispersal 24 23. Percentage and composition of volcanic constituents in Ogallala and probable Ogallala gravels 25 24. Percentage and composition of sedimentary constituents in Ogallala and probable Ogallala gravels 26 25. Selected transects of upper Canadian basin and Canadian breaks 26. Postulated network geometry of Pliocene drainage during basal Ogallala deposition 33 27. Effects of evaporite dissolution collapse on Ogallala deposition 34 28. Pleistocene climate and sedimentation, Canadian River basin 38 29. Modern and postulated last full-glacial timberline, montane border of the Canadian basin 41 30. Postulated changes in selected geomorphic processes accompanying full-glacial cooling 42 Postulated response of semiarid plains drainage to a shift toward Pleistocene full-glacial conditions 43 32. Paleohydrologic response of the fluvial system to Pleistocene climatic shifts 43 33. Pleistocene conditions, continental interior, for valley incision and alluviation, and soil formation 44 34. Regional equivalence and approximate absolute ages of Pleistocene pediment levels 45 35. Correlation of selected pediment and related erosion surface levels 46 36. Correlation of selected erosion surface levels 47 37. Potassium-argon dates for volcanic rocks in the Canadian River basin 50 38. Major surface structural and physiographic features of a portion of the montane Canadian basin 51 39. Middle Pliocene erosion surface, montane border, Canadian River basin 53 40. Relationship of Ogallala depositional geometry to Pleistocene drainage network geometry ... 59 41. Elevations above local base level of selected erosion surfaces, Ocate and Raton volcanic fields 60 42. Pattern of Canadian network entrenchment relative to igneous activity and axes of major structures 62 43. Nature, timing, and regional extent of factors controlling drainage, Raton and High Plains sections 63 44. Postulated High Valley fluvial network, late Pleistocene .65 45. Postulated High Valley fluvial network, middle Pleistocene 65 46. Postulated High Valley fluvial network, late Pleistocene-Holocene 65 47. Elevations and gradients of Mora River, early Pleistocene Maxson Crater basalt flow and adjacent late Pliocene Dakota upland 67 48. Lithologic contrast, major carbonate provenance areas of upper Pecos and upper Canadian drainage basins 68 49. Outcrop extent of major carbonate provenance areas defined in Fig. 48 69 50. Relationship of subsurface structure and modern fluvial landscape to Permian evaporite dissolution, Canadian breaks and High Plains border 72 Stratigraphic nomenclature, Permian and younger strata beneath the Canadian breaks 74 52. Gerty Sand, its relationship to modern drainage pattern and regional bedrock structure 75 53. Pleistocene deposits and paleodrainage map, third bend, South Canadian River 76 54. Geologic cross section, western Osage Plains 78 Cenozoic Evolution of the Canadian River Basin Paul N. DoUiver ABSTRACT Given the landscape scale and time span being con­ and episodic entrenchment in response to epeirogenic sidered, the Cenozoic history of the Canadian River uplift and cyclic climatic change. basin is best depicted in terms of changing surface geol­ Eastward-flowing Raton-High Plains Canadian tribu­ ogy, landscape and drainage network morphology, cli­ taries established their modern courses during a short mate/ vegetation, and hydrology. interval spanning the Pliocene-Pleistocene boundary. Drainage history of what is now the Canadian basin Lateral diversion of streams draining the terminal Ogal­ began with regression of a Late Cretaceous epicontinen- lala alluvial plain intensified under the influence of late sea during early stages of Laramide tectonism. Rising Pliocene epeirogenic movement. The drainage network cratonic uplifts governed the pattern of continental changed radically as formerly consequent streams were emergence and early subaerial drainage. southeast- reoriented subsequent to structures such as the Sierra flowing rivers developed by early Eocene time, following Grande arch. The new drainage pattern rapidly stabilized paths of tectonic "least resistance" to the Gulf of Mexico. as continued tectonism and initial Pleistocene glaciation These avenues of regional fluvial sediment transport per­ caused widespread entrenchment. Entrenchment was sisted throughout late Eocene erosion surface formation most pronounced just north of the Canadian-Arkansas and subsequent widespread Oligocene-Miocene aggrada­ divide, where the early Pleistocene Cimarron River tion. became incised to near its present level. Most changes in Ogallala sediments and the topography that they ob­ the fluvial landscape after network stabilization were scure permit the earliest detailed reconstruction of the confined to stream valley deepening and widening proto-Canadian basin. Most basal gravel of the Ogallala brought on by middle to late Pleistocene climatic Formation within the Canadian basin area originated in reversals.
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