DOCSLIB.ORG

Erosional Cycles in the Front Range of Colorado and Their Correlation 1

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Erosional Cycles in the Front Range of Colorado and Their Correlation 1 BULLETIN OF THE GEOLOGICAL SOCIETY OF AMERICA W VOL. 36. PP. 498-512 SEPTEMBER 30. 1925 EROSIONAL CYCLES IN THE FRONT RANGE OF COLORADO AND THEIR CORRELATION 1 BY HOJIKR P. LITTLE (P resented in abstract before the Society December 29, J02J,1) CONTENTS Puice Introduction................................................. ......................................................................... 495 Peneplains of the Front Range................................................................................. 497 General statement...................................................................................................... 497 The Flattop peneplain............................................................................................... 498 The Rocky Mountain peneplain............................................................................. 500 The Park stage............................................................................................................. 504 The Fountain Creek stage....................................................................................... 507 The Canyon-cutting stage........................................................................................ 509 Age and correlation of erosion cycles..................................................... ............... 509 Discussion......................................................: ....................................................................... 510 Bibliography.......................................................................................................................... 511 INTRODUCTION' This paper is the result of work done during July and early August in the summer of 19‘24. The work was financed by (’lark University and received the cordial cooperation of the United States Geological Survey. Particular thanks are due to W. C. Mendenhall, of the Washington office, and C. W. Henderson, of the Denver office. The writer was assisted in the field during the season by Rollin Atwood and in the last few days had the benefit of the field • advice of Wallace W. Atwood and Kirtley Mather. The objective of the work was the study of the peneplains of the Front Range with a view to applying the facts brought out by Lee’s work in Rocky Mountain National Park to other parts of the range and adding such new facts to its erosiona! history as could be discovered. It was especially desired to establish more definitely than previously the age of 1 Manuscript received by the Secretary of the Society April 13, 1025. (495) Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/36/3/495/3429942/BUL36_3-0495.pdf by guest on 30 September 2021 496 H. P. LITTLE----EROSIONAL CYCLES IN THE FRONT Ii] f à c h e y e n n e iS TIE SIDING- • •SH E R M A N \» WYOMING ’$f ” C O L O R A D O ' ' f o •®*-E N D t VEV «LIV E R M O R E \ * • HOME )\r XrALL Riven PASS £ . 0 * §1 XMILNER PASS ' ' C ^ i N T A L p\V \ \ «ESTES PARK \-^feLONCS PEAK [ • AV-LEMSPARK \ \ , W A R D / • B O O L D i R I «NEDERLAND CORONA » I »ROLLINSVILLE BEKTHOVV P A « , * . ' C E N T . R.ABLUC^ i A W K ¿75 / « IDAHOSPRKWS* golden « ( ® D E N V E R P l ^ ’*oRfrET<IWN BERCEN M R K V * */7yijfe. «EVERGREEN . A' MT. E V A N S SOUTH PLATTE • CA STLE ROCK M d e v il s HEAD PEAK t»».PALMER LAKE TARRVALL* # • WtODLANO PARK FLORISSANT DIVIDE ,GREEN MT. FALLS paKEs«AR'% • Colorado « g i l l e t t s p r i n g s CRI PPLE CREEK • o s to a»© 3o i/o k m* SCALEI INj MILESI = -H F ig u u e 1.—Index Hap Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/36/3/495/3429942/BUL36_3-0495.pdf by guest on 30 September 2021 PENEPLAINS OF THE FRONT RANGfc! 4 9 7 the major peneplains, and to establish a correlation with those of other portions of the Rocky Mountains. In this work most of the mountain roads between Colorado Springs and Estes Park were penetrated, as well as much of the adjoining region; a rapid survey was then made of the territory from Estes Park northward to Tie Siding, in southern Wyo- miug, where Blackwelder described the Sherman peneplain, and thence to Glendevey and Green Ridge, a splendid remnant, for knowledge of whose existence the writer is indebted to Dean Worcester, of the Uni­ versity of Colorado (figure 1). South from Colorado Springs the area of the Royal Gorge was penetrated, and for the sake of comparison the writer undertook a three weeks’ trip to the San Juan Mountains with Wallace W. Atwood to examine the peneplains described by him there. 'New evidence of the age of the peneplains from observation within the range itself was not obtained, but Mather, from observations to the north­ east of Port Collins, secured very definite evidence, and it seems safe to correlate most of his stages with those of the Eront Range. Many published articles were of assistance in the work, especially those of Ball, Davis, Blackwelder, and Lee. These and other articles consulted are listed at the end of the paper, but do not comprise a complete bibliog­ raphy of the subject. P e n e p l a in s of t h e F r o n t R a n g e « GENERAL STATEMENT For practical purposes, though not with absolute accuracy, the pene­ plains of the Front Range may be considered as cut wholly across pre- Cambrian granites, gneisses, and schists, with the former especially abundant. Except on the steepest slopes, the region traversed by roads is covered with the coarse sand characteristic of disintegrated but undecom­ posed granite. Soils are occasionally evident, as in road cuts just south of Bergen Park. These, however, are in the majority of cases the prod­ ucts of weathering of the less resistant schistose rocks. The erosional history of the Front Range will be described under the headings Flattop Peneplain, Rocky Mountain Peneplain, Park Cycle, Fountain Creek Cycle, and Canyon-cutting Cycle. Of these terms, the third and fourth are here used for the first time. Discussion of these surfaces groups around four areas where remnants arc particularly conspicuous, namely, the Pikes Peak region, the Bergen Park-Evergreen region, the Rollinsville-Nederland-Ward region, and the Estes Park and Vicinity region. Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/36/3/495/3429942/BUL36_3-0495.pdf by guest on 30 September 2021 498 H. r. LITTLE----EROSIONAL CYCLES IN THE FRONT RANGE THE FLATTOP PEXEPLAIS The Flattop peneplain was so named by Lee in 1917 because of the wide extent of its development on Flattop Mountain, in Rocky Mountain ATational Park. Here it occurs at an elevation of 12,300 feet. He cor­ related it with the surface described by Ball in the Georgetown Quad­ rangle, and the latter’s description will serve for the region as a whole: “The mountainous upland was an ancient land surface with about the same relief as the present surface. Dome-shaped mountains and broad, 'smoothly contoured ridges, however, stood where sharp peaks and rugged ridges now are. The drainage was dendritic and mature. The remnants of this old topographic surface are covered by rock residuals and in many places by deep soil.” The surface of Flattop Mountain is, as said above, the type area (figure 2). The shoulders of Hagues Peak, when seen from any point in Estes Park, show the old surface almost as well (figure 3), and considerable areas may be seen along Trail Ridge, which is easily accessible from Fall River Pass. Twenty-five miles to the south, along the Continental Divide, are the peneplain remnants at Corona described by Davis, also at an elevation of about 12.000 feet. A few more miles to the southward, and visible from Corona, is the extensive remnant from the western edge of which James Peak rises as a prominent monadnock to a height of over 13,000 feet. A large remnant previously undescribed occurs near the point where the Continental Divide makes its turn to the west, about 10 miles southwest of James Peake. This remnant, which is one of the largest and most level areas in the entire region (figure 4), is easily visible northwest of Berthoud Pass. Its position may be determined from the road by the flat crest line of the large cirque which is cut into its surface. Although this remnant is off the topographic map, its eleva­ tion relative to Berthoud Pass shows that it must be at least 11,500 feet in altitude. Another ten miles to the south is the. Georgetown area described by Ball. This rather inaccessible area was not studied in detail. However, the proposed road to Mount Evans, which now extends to within three miles in an air line from the mountain, was traversed to its end. From this the mature topography of the upland country is strikingly evident. The suggestion is made that the somewhat even-crested ridge extending for three miles west of Chief Mountain at an elevation of 11,000 feet may represent the Flattop surface, and the great mature areas2 south and west 3 This area and much of that to the east and soufh may be best studied from the Denver Moan lain Parks sheet, advance copies of which were available for use in the field through the courtesy of the Denver office of the U. S. Geological Survey. Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/36/3/495/3429942/BUL36_3-0495.pdf by guest on 30 September 2021 PENEPLAINS OF THE FRONT RANGE F ig u re 2.— Surface of Flattop Peneplain Flattop Mountain in the foreground. Altitude, 12,300 feet. The monadnock of Hallett Peak is at the left and Longs Peak in the distance. F igure 3.—IIagues Peak from Prospect Mountain3 Estes Park The flat shoulders of Hagues Peak represent the Flattop peneplain. The ridge in the middle ground—elevation, 10,000 feet—represents the Rocky Mountain peneplain, and the low area in the foreground the Park stage. XXXIII—B ull. Geol. Soc. A.m., Vol. 36, 1924 Downloaded from http://pubs.geoscienceworld.org/gsa/gsabulletin/article-pdf/36/3/495/3429942/BUL36_3-0495.pdf by guest on 30 September 2021 500 H. P. LITTLE----EROSIONAL CYCLES IN THE FRONT RANGE of Mount Evans, although not visited, may be conjectured from the map to represent other remnants.
Load more

Recommended publications
  • Part 629 – Glossary of Landform and Geologic Terms
    Title 430 – National Soil Survey Handbook Part 629 – Glossary of Landform and Geologic Terms Subpart A – General Information 629.0 Definition and Purpose This glossary provides the NCSS soil survey program, soil scientists, and natural resource specialists with landform, geologic, and related terms and their definitions to— (1) Improve soil landscape description with a standard, single source landform and geologic glossary. (2) Enhance geomorphic content and clarity of soil map unit descriptions by use of accurate, defined terms. (3) Establish consistent geomorphic term usage in soil science and the National Cooperative Soil Survey (NCSS). (4) Provide standard geomorphic definitions for databases and soil survey technical publications. (5) Train soil scientists and related professionals in soils as landscape and geomorphic entities. 629.1 Responsibilities This glossary serves as the official NCSS reference for landform, geologic, and related terms. The staff of the National Soil Survey Center, located in Lincoln, NE, is responsible for maintaining and updating this glossary. Soil Science Division staff and NCSS participants are encouraged to propose additions and changes to the glossary for use in pedon descriptions, soil map unit descriptions, and soil survey publications. The Glossary of Geology (GG, 2005) serves as a major source for many glossary terms. The American Geologic Institute (AGI) granted the USDA Natural Resources Conservation Service (formerly the Soil Conservation Service) permission (in letters dated September 11, 1985, and September 22, 1993) to use existing definitions. Sources of, and modifications to, original definitions are explained immediately below. 629.2 Definitions A. Reference Codes Sources from which definitions were taken, whole or in part, are identified by a code (e.g., GG) following each definition.
    [Show full text]
  • Origin of the High Elevated Pyrenean Peneplain Julien Babault, Jean Van Den Driessche, Stéphane Bonnet, Sébastien Castelltort, Alain Crave
    Origin of the high elevated Pyrenean peneplain Julien Babault, Jean van den Driessche, Stéphane Bonnet, Sébastien Castelltort, Alain Crave To cite this version: Julien Babault, Jean van den Driessche, Stéphane Bonnet, Sébastien Castelltort, Alain Crave. Origin of the high elevated Pyrenean peneplain. Tectonics, American Geophysical Union (AGU), 2005, 24 (2), art. no. TC2010, 19 p. 10.1029/2004TC001697. hal-00077900 HAL Id: hal-00077900 https://hal.archives-ouvertes.fr/hal-00077900 Submitted on 29 Jun 2016 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. TECTONICS, VOL. 24, TC2010, doi:10.1029/2004TC001697, 2005 Origin of the highly elevated Pyrenean peneplain Julien Babault, Jean Van Den Driessche, and Ste´phane Bonnet Ge´osciences Rennes, UMR CNRS 6118, Universite´ de Rennes 1, Rennes, France Se´bastien Castelltort Department of Earth Sciences, Eidgenossische Technische Hochschule-Zentrum, Zurich, Switzerland Alain Crave Ge´osciences Rennes, UMR CNRS 6118, Universite´ de Rennes 1, Rennes, France Received 9 June 2004; revised 5 December 2004; accepted 13 December 2004; published 19 April 2005. [1] Peneplanation of mountain ranges is generally base level in the penultimate stage of a humid, fluvial considered the result of long-term erosional processes geomorphic cycle.’’ They specify that ‘‘peneplain’’ also that smooth relief and lower elevation near sea level.
    [Show full text]
  • Etchplain, Rock Pediments, Glacises and Morphostructural Analysis of the Bohemian Massif (Czech Republic) Jaromir Demek [email protected] Rudka Č
    GeoMorfostrukturnímorfologický a sborník tektonické 2 problémy ČAG, ZČU v Plzni, 2003 Etchplain, rock pediments, glacises and morphostructural analysis of the Bohemian Massif (Czech Republic) Jaromir Demek [email protected] Rudka č. 66, Kunštát na Moravě CZ 679 72 The Bohemian Massif forms the western part of Czech Republic. The massif belongs to the Western European Platform, which basement was consolidated by Variscan folding. The Bohemian Massif is characterized by a typical platform regime during Mesozoic and Paleogene Periods, i.e. by low intensity of tectonic movements and slight relief differentiation. This regime was reflected in a structural compatibility and morphological uniformity of the Massif, with altitudes of its planated surface (mostly peneplain with thick regolith mantle) ranging from 0 to 200 m a.s.l. The present-day relief of the Bohemian Massif developed for the most part in the Neotectonic period (Upper Oligocene to Quaternary). The older idea that o the Bohemian Massif responded to stresses caused by neotectonic movements generally as a rigid unit (with some differences in individual regions) and o that in the Bohemian Massif preserved in very large extent old peneplain (KUNSKÝ, 1968, p. 27), seams to be abandoned now. Already in 1930 Ms. Julie Moschelesová proposed the hypothesis of neotectonic megaanticlinals and megasynclinals in the basement of the Bohemian Massif. At present the Bohemian Massif is understood as a complex mountain, which relief is composed of megaanticlinals and megasynclinals, horstes and grabens and volcanic mountains? Individual parts of the Bohemian Massif moved in different directions and with different intensity during Neotectonic Period. The determination of directions, intensity and type of Neotectonic deformations of the Earth’s crust is difficult due to lack of correlated deposits.
    [Show full text]
  • 2 Observation in Geomorphology
    2 Observation in Geomorphology Bruce L. Rhoads and Colin E. Thorn Department of Geography, University of Illinois at Urbana-Champaign ABSTRACT Observation traditionally has occupied a central position in geomorphologic research. The prevailing, tacit attitude of geomorphologists toward observation appears to be consistent with radical empiricism. This attitude stems from a strong historical emphasis on the value of fieldwork in geomorphology, which has cultivated an aesthetic for letting the data speak for themselves, and from cursory and exclusive exposure of many geomorphologists to empiricist philosophical doctrines, especially logical positivism. It is, by and large, also an unexamined point of view. This chapter provides a review of contemporary philosophical perspectives on scientific observation. This discussion is then used as a filter or lens through which to view the epistemic character and role of observation in geomorphology. Analysis reveals that whereas G.K. Gilbert's theory-laden approach to observation preserved scientific objectivity, the extreme theory-ladenness of W.M. Davis's observational procedures often resulted in considerable subjectivity. Contemporary approaches to observation in geomorphology are shown to conform broadly with the model provided by Gilbert. The hallmark of objectivity in geomorphology is the assurance of data reliability through the introduction of fixed rule-based procedures for obtaining information. INTRODUCTION Geomorphologists traditionally have assigned great virtue to observation. The venerated status of observation can be traced to the origin of geomorphology as a field science in the late 1800s. Exploration of sparsely vegetated landscapes in the American West by New- berry, Powell, Hayden, Gilbert, and others inspired perceptive insights about landscape dynamics that provided a foundation for the discipline (Baker and Twidale 1991).
    [Show full text]
  • A Geomorphic Classification System
    A Geomorphic Classification System U.S.D.A. Forest Service Geomorphology Working Group Haskins, Donald M.1, Correll, Cynthia S.2, Foster, Richard A.3, Chatoian, John M.4, Fincher, James M.5, Strenger, Steven 6, Keys, James E. Jr.7, Maxwell, James R.8 and King, Thomas 9 February 1998 Version 1.4 1 Forest Geologist, Shasta-Trinity National Forests, Pacific Southwest Region, Redding, CA; 2 Soil Scientist, Range Staff, Washington Office, Prineville, OR; 3 Area Soil Scientist, Chatham Area, Tongass National Forest, Alaska Region, Sitka, AK; 4 Regional Geologist, Pacific Southwest Region, San Francisco, CA; 5 Integrated Resource Inventory Program Manager, Alaska Region, Juneau, AK; 6 Supervisory Soil Scientist, Southwest Region, Albuquerque, NM; 7 Interagency Liaison for Washington Office ECOMAP Group, Southern Region, Atlanta, GA; 8 Water Program Leader, Rocky Mountain Region, Golden, CO; and 9 Geology Program Manager, Washington Office, Washington, DC. A Geomorphic Classification System 1 Table of Contents Abstract .......................................................................................................................................... 5 I. INTRODUCTION................................................................................................................. 6 History of Classification Efforts in the Forest Service ............................................................... 6 History of Development .............................................................................................................. 7 Goals
    [Show full text]
  • Critical Review of the San Juan Peneplain Southwestern Color~ Do
    Critical Review of the San Juan Peneplain Southwestern Color~ do GEOLOGICAL SURVEY PROFESSIONAL PAPER 594-I Critical Review of the San Juan Peneplain Southwestern Colorado By THOMAS A. STEVEN SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY GEOLOGICAL SURVEY PROFESSIONAL -PAPER 594-I The volcanic and geomorphic history of the San Juan Mountains indicates no peneplain cycle of erosion between the end of ma;·or volcanism and the present time UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1968 UNITED STATES DEPARTMENT OF THE INTERIOR STEWART L. UDALL, Secretary GEOLOGICAL SURVEY William T. Pecora, Director For sale by the Superintendent of Documents, U.S. Government Printing Office Washington, D.C. 20402 CONTENTS Page Page Albstract ----------------------------------------­ I 1 Discussion of the San Juan peneplain-Continued Introduction -------------------------------------­ 1 3. The peneplain remnants -------------------- 18 Alcknowledgments --------------------------------- 2 4. Postpeneplain deformation -------------------- 9 General geology of the San Juan region ___________ _ 2 5. Postpeneplain alluviation and volcanism ______ _ 10 The peneplain concept ----------------------------­ 4 6. Postpeneplain development of drainage_------- 12 Discussion of the San Juan peneplain -------------- 6 Possible character of the late Tertiary landscape ___ _ 13 1. Subsidence of the prevolcanism erosion surface _ 6 Summary ----·------------------------------------ 14 2. Volcanism and volcano-tectonic deformation Catalog of peneplain remnants ----------------------
    [Show full text]
  • Long-Term Landscape Evolution, Genesis, Distribution and Age
    GONDWANA PALEOLANDSCAPES: LONG-TERM LANDSCAPE EVOLUTION, GENESIS, DISTRIBUTION AND AGE Jorge RABASSA 1,2 (1) Laboratorio de Cuaternario y Geomorfología, CADIC-CONICET, Bernardo Houssay 200, 9410. Tierra del Fuego, Argentina. E-mail: [email protected] (2) Universidad Nacional de la Patagonia - San Juan Bosco, Sede Ushuaia. “Let the landscape teach me” Lester C. King, personal letter to Charles Higgins, 1958. “While the geologist may often be in error, the Earth is never wrong” Lester C. King, 1967. Introduction The Concepts of Gondwana Paleolandscapes and Long-Term Landscape Evolution: Previous Works Gondwana Paleolandscapes: Basic Scientific Concepts Related The Evolution of the Gondwana Cratonic Areas During the Mesozoic Mesozoic and Paleogene Climates Granite Deep Weathering Passive-Margin Geomorphology Duricrusts: Ferricretes, Silcretes, Calcretes A Brief and Preliminary Review of Gondwana Landscapes and Other Ancient Paleolandscapes in the Southern Hemisphere and Other Parts of the World Discussion and Conclusions Acknowledgements Bibliographic References ABSTRACT – The concept of “Gondwana Landscape” was defined by Fairbridge (1968) as an “ancestral landscape” composed of “series of once-planed remnants” that “record traces of older planation” episodes, during the “late Mesozoic (locally Jurassic or Cretaceous)”. This has been called the “Gondwana cyclic land surface” in the continents of the southern hemisphere, occurring extensively in Australia, Southern Africa and the cratonic areas of South America. Remnants of these surfaces are found also in India, in the northern hemisphere and it is assumed they have been preserved in Eastern Antarctica, underneath the Antarctic ice sheet which covers that region with an average thickness of 3,000 meters. These paleolandscapes were generated when the former Gondwana super-continent was still in place and similar tectonic conditions in its drifted fragments have allowed their preservation.
    [Show full text]
  • Alphabetical Glossary of Geomorphology
    International Association of Geomorphologists Association Internationale des Géomorphologues ALPHABETICAL GLOSSARY OF GEOMORPHOLOGY Version 1.0 Prepared for the IAG by Andrew Goudie, July 2014 Suggestions for corrections and additions should be sent to [email protected] Abime A vertical shaft in karstic (limestone) areas Ablation The wasting and removal of material from a rock surface by weathering and erosion, or more specifically from a glacier surface by melting, erosion or calving Ablation till Glacial debris deposited when a glacier melts away Abrasion The mechanical wearing down, scraping, or grinding away of a rock surface by friction, ensuing from collision between particles during their transport in wind, ice, running water, waves or gravity. It is sometimes termed corrosion Abrasion notch An elongated cliff-base hollow (typically 1-2 m high and up to 3m recessed) cut out by abrasion, usually where breaking waves are armed with rock fragments Abrasion platform A smooth, seaward-sloping surface formed by abrasion, extending across a rocky shore and often continuing below low tide level as a broad, very gently sloping surface (plain of marine erosion) formed by long-continued abrasion Abrasion ramp A smooth, seaward-sloping segment formed by abrasion on a rocky shore, usually a few meters wide, close to the cliff base Abyss Either a deep part of the ocean or a ravine or deep gorge Abyssal hill A small hill that rises from the floor of an abyssal plain. They are the most abundant geomorphic structures on the planet Earth, covering more than 30% of the ocean floors Abyssal plain An underwater plain on the deep ocean floor, usually found at depths between 3000 and 6000 m.
    [Show full text]
  • Peneplains and Related Land Forms
    No. 3622, APRIL 1, 1939 NATURE 569 while they are attending classes ! The corridor floors Dr. Lowery again, "it is our desire that the College are covered with grey mottled rubber to render the shall become one great educational and recreational movement of students as silent as possible, and community centre where men and women may meet supplementary to the main staircases, passenger lifts in their leisure time for the purpose of engaging in have been installed. matters of common interest, thereby securing the It was John Ruskin who wrote, many years ago, fullest opportunity for self-expression". "The entire object of true education is to make The material building of this huge college has been people not merely do the right things but enjoy the very efficiently carried out by the general contractors, right things". Yet, the pioneers of technical educa­ Messrs. F. R. Hipperson and Son, Ltd., of London, tion were mainly concerned with providing a training to the plans of Mr. J. Stuart, the architect, but an which was severely utilitarian. But, as Dr. H. even greater work will now be undertaken by the Lowery, the principal of the College, aptly points out, principal and his large staff in laying the foundations "A new problem . has arisen-it becomes of another edifice which will undoubtedly reveal necessary to provide training for leisure as well as itself in the trained mind, skilled craftsmanship, for vocation". Here then is a new function implying cultured recreation and, what is most important of heavy responsibilities for the modern college. It is all, trustworthiness and reliability of character.
    [Show full text]
  • The Paradox of Equivalence of the Davisian End-Peneplain and Penckian Primary Peneplain
    Concepts and Modelling in Geomorphology: International Perspectives, Eds. I. S. Evans, R. Dikau, E. Tokunaga, H. Ohmori and M. Hirano, pp. 3–32. © by TERRAPUB, Tokyo, 2003. The Paradox of Equivalence of the Davisian End-Peneplain and Penckian Primary Peneplain Hiroo OHMORI Department of Natural Environmental Studies, Graduate School of Frontier Sciences, The University of Tokyo, 7-3-1 Hongo, Bukyo-ku, Tokyo 113-0033, Japan e-mail: [email protected] Abstract. The Davisian model elucidates landscape development through an orogeny by denudation processes, postulating prolonged still-stand of a landmass following rapid tectonic uplift, ultimately resulting in a peneplain. The Penckian model emphasizes that landscape is shaped by concurrent tectonics and denudation, and includes the primary peneplain as an antithesis against the Davisian end-peneplain by assuming a steady state between tectonic uplift and denudation from the beginning of orogenesis. Every ordinary landscape development through an orogeny has been expected to follow a course located between the two distinctive courses of landscape development. On the basis of the relationships between mountain altitude, local relief and denudation rate observed in Japan, denudation rate increases with local relief and the local relief increases with mountain altitude. A mountain range is considerably denuded even during the uplift phase. As denudation rate approaches tectonic uplift rate with an increase in mountain altitude by tectonic uplift, a steady state between denudation and uplift appears, and the mountain range attains a critical altitude that remains constant, in spite of continuous tectonic uplift. If tectonic uplift ceases, the mountain range is lowered by denudation, resulting in a subdued low relief landscape, ultimately a peneplain.
    [Show full text]
  • Planation Surfaces As a Record of Mantle Dynamics
    Planation surfaces as a record of mantle dynamics: The case example of Africa François Guillocheau, Brendan Simon, Guillaume Baby, Paul Bessin, Cécile Robin, Olivier Dauteuil To cite this version: François Guillocheau, Brendan Simon, Guillaume Baby, Paul Bessin, Cécile Robin, et al.. Planation surfaces as a record of mantle dynamics: The case example of Africa. Gondwana Research, Elsevier, 2018, 53, pp.82-98. 10.1016/j.gr.2017.05.015. insu-01534695 HAL Id: insu-01534695 https://hal-insu.archives-ouvertes.fr/insu-01534695 Submitted on 8 Jun 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Accepted Manuscript Planation surfaces as a record of mantle dynamics: The case example of Africa François Guillocheau, Brendan Simon, Guillaume Baby, Paul Bessin, Cécile Robin, Olivier Dauteuil PII: S1342-937X(17)30249-6 DOI: doi: 10.1016/j.gr.2017.05.015 Reference: GR 1819 To appear in: Received date: 4 June 2016 Revised date: 15 May 2017 Accepted date: 18 May 2017 Please cite this article as: François Guillocheau, Brendan Simon, Guillaume Baby, Paul Bessin, Cécile Robin, Olivier Dauteuil , Planation surfaces as a record of mantle dynamics: The case example of Africa, (2017), doi: 10.1016/j.gr.2017.05.015 This is a PDF file of an unedited manuscript that has been accepted for publication.
    [Show full text]
  • Competition Between Stream Erosion, Cave Development, Surface Denudation, and Tectonic Uplift
    W.B. White – The evolution of Appalachian fluviokarst: competition between stream erosion, cave development, surface denudation, and tectonic uplift. Journal of Cave and Karst Studies, v. 71, no. 3, p. 159–167. THE EVOLUTION OF APPALACHIAN FLUVIOKARST: COMPETITION BETWEEN STREAM EROSION, CAVE DEVELOPMENT, SURFACE DENUDATION, AND TECTONIC UPLIFT WILLIAM B. WHITE Department of Geosciences and Materials Research Institute, The Pennsylvania State University, University Park, PA 16802, [email protected] Abstract: The long and complex depositional and tectonic history of the Appalachians has produced a substrate of folded and faulted sandstones, shales, and carbonate rocks (leaving aside the metamorphic and igneous core). The Appalachian fluviokarst is an evolving landscape developed on the carbonate rocks. The erosion of surface streams competes with dissolutional processes in the carbonate rocks, and both compete with tectonic uplift of the eastern margin of the North American plate. The Appalachians have undergone erosion since the Jurassic and 5 to 15 km of sediment have been removed. Many karst landscapes have come and gone during this time period. The earliest cosmogenic- isotope dates place the oldest Appalachian caves in the early Pliocene. Various interpretations and back-calculations extend the recognizable topography to the mid to late Miocene. Much of the present-day karst landscape was created during the Pleistocene. There have been many measurements and estimates of the rate of denudation of karst surfaces by dissolution of the carbonate bedrock and many estimates of the rate of downcutting of surface streams. Curiously, both of these estimates give similar values (in the range of 30 mm ka21), in spite of the differences in the erosional processes.
    [Show full text]