Planation Surfaces As a Record of Mantle Dynamics
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Interpretation of Cumberland Escarpment and Highland Rim, South-Central Tennessee and Northeast Alabama
Interpretation of Cumberland Escarpment and Highland Rim, South-Central Tennessee and Northeast Alabama GEOLOGICAL SURVEY PROFESSIONAL PAPER 524-C Interpretation of Cumberland Escarpment and Highland Rim, South-Central Tennessee and Northeast Alabama By JOHN T. HACK SHORTER CONTRIBUTIONS TO GENERAL GEOLOGY GEOLOGICAL SURVEY PROFESSIONAL PAPER 524-C Theories of landscape origin are compared using as an example an area of gently dipping rocks that differ in their resistance to erosion UNITED STATES GOVERNMENT PRINTING OFFICE, WASHINGTON : 1966 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 Abstract___________________________________________ C1 Cumberland Plateau and Highland Rim as a system in Introduction_______________________________________ 1 equilibrium______________________________________ C7 General description of area___________________________ 1 Valleys and coves of the Cumberland Escarpment___ 7 Cumberland Plateau and Highland Rim as dissected and Surficial deposits of the Highland Rim____________ 10 deformed peneplains _____________________ ,... _ _ _ _ _ _ _ _ 4 Elk River profile_______________________________ 12 Objections to the peneplain theory____________________ 5 Paint Rock Creek profile________________________ 14 Eastern Highland Rim Plateau as a modern peneplain__ 6 Conclusions________________________________________ 14 Equilibrium concept -
AJST) Science and Engineering Series Vol
African Journal of Science and Technology (AJST) Science and Engineering Series Vol. 4, No. 2, pp. 80-89 ISOTOPE AND GEOCHEMICAL CHARACTERIZATION OF SURFACE AND SUBSURFACE WATERS IN THE SEMI-ARID SOKOTO BASIN, NIGERIA S.M.A. Adelana1, P.I. Olasehinde1 and P.Vrbka2 1Department of Geology & Mineral Sciences, University of Ilorin, P.M.B. 1515, Ilorin, Kwara State, Nigeria. 2Kaupstrasse 37, Germany (formerly Geology Institute, Technical University Darmstadt, Germany). ABSTRACT:- Stable isotopes and geochemical studies have been applied in the investigation of groundwater resources in Sokoto Basin, northwestern Nigeria. Generally, the characteristic hydrochemical classification in the study area is calcium-alkali-bicarbonate. Surface waters are characterized by alkali-calcium-bicarbonate while groundwater is of Ca-Mg-HCO3. The plot of δ18O versus δ2H shows that five isotopic groups can be distinguished. Group I-III is of groundwater origin while group IV and V represent surface water. A combination of the hydrochemical and isotope data (14C, 13C and 3H) reveals the Sokoto basin aquifers generally contains good quality groundwater of Holocene age (100 to 10,000 years BP). Keywords: stable isotopes, geochemical characterization, groundwater, Sokoto Basin. INTRODUCTION condition by one kilometre yearly into northern Nigeria threatens agriculture. It is in the light of this that the Northwestern Nigeria is a region with great potential for Federal government of Nigeria under a joint project with future large-scale economic development due to warm the International Atomic and Energy Agency, Vienna has temperatures and bountiful resources; including thermal planned a number of irrigation schemes in order to energy, farmlands and minerals. Water resources data in increase agricultural activities in the area to two planting this area, as far back as the 60s, are available in literature seasons, thereby boosting food production. -
Chapter 40. Appalachian Planation Surfaces
Chapter 40 Appalachian Planation Surfaces The Appalachian region not only includes the mountains, but also the surrounding provinces. During the erosion episode (see Chapter 8 and Appendix 4), rocks of the Appalachians were sometimes planed into a flat or nearly flat planation surface, especially on the provinces east and west of the Blue Ridge Mountains (Figure 40.1). But planation surfaces are also found in the Appalachian Mountains, mainly on the mountaintops. Figure 40.1. Map of the Appalachian provinces and the two provinces to the west (from Aadland et al., 1992). Due to their rolling and dissected morphology, the Appalachian provinces are rarely called planation surfaces, but they would mostly be erosion surfaces. I will continue to use the more descriptive term, planation surface, with the understanding that many of these are erosion surfaces. The Appalachian provinces exhibit three possible planation surfaces, from east to west, they include: (1) the Piedmont Province, (2) the accordant mountaintops of the Valley and Ridge Province (part of the Appalachian Mountains), and (3) the Appalachian Plateau which is divided into the Allegheny Plateau in the north and the Cumberland Plateau in the south. I also will include the Interior Low Plateaus Province to the west of the Appalachian Plateau. Many articles have been published about the Appalachian planation surface. Their origin is controversial among secular geologists, but they can readily be explained by the runoff of the global Genesis Flood. Figure 40.2. Lake on the Piedmont near Parkersville, South Carolina, showing general flatness of the terrain. The Piedmont Planation Surface The Piedmont Province begins just east of the Blue Ridge Mountains from the Hudson River in the north to Alabama in the south. -
The Long-Term Evolution of the Congo Deep-Sea Fan: a Basin-Wide View of the Interaction Between a Giant Submarine Fan and a Mature Passive Margin (Zaiango Project)
The Congo deep-sea fan: how far and for how long? A basin-wide view of the interaction between a giant submarine fan and a mature passive margin Zahie Anka 1,*, Michel Séranne 2,**, Michel Lopez 2, Magdalena Scheck-Wenderoth 1, Bruno Savoye 3,†. 1. GFZ German Research Centre for Geosciences. Telegrafenberg, 14473 Potsdam, Germany. 2. CNRS-Université Montpellier II. cc 060, Geosciences Montpellier. 34095 Montpellier, France. 3. IFREMER, Geosciences Marines, BP 70 — 29280 Plouzané, France. (*) [email protected] (**) [email protected] (†) deceased 1.- Introduction The Congo deep-sea fan is one of the largest submarine fan systems in the world and one of the most important depocentre in the eastern south Atlantic. The present-day fan extends over 1000 km offshore the Congo-Angola continental margin and it is sourced by the Congo River, whose continental drainage area is the second largest in the world (3.7 106 km²) (Droz et al., 1996) (Fig.1). There is a direct connexion between the river’s drainage basin and the deep basin through an impressive submarine canyon, which cuts down about 950 m at the shelf-break and more than 1300 m at 100 km offshore the coastline (Babonneau et al., 2002). Hence, the direct transfer of terrigenous material onto the abyssal plain takes place through the canyon, by-passing the shelf and upper slope. The submarine fan covers a surface of about 300,000 km² and contains at least 0.7 Mkm³ of Tertiary sediments (Anka and Séranne, 2004; Droz et al., 2003; Savoye et al., 2000). -
Oblique Rifting of the Equatorial Atlantic: Why There Is No Saharan Atlantic Ocean
Originally published as: Heine, C., Brune, S. (2014 online): Oblique rifting of the Equatorial Atlantic: Why there is no Saharan Atlantic Ocean. – Geology 10.1130/G35082.1. Oblique rifting of the Equatorial Atlantic: Why there is no Saharan Atlantic Ocean 1 2,1 Christian Heine , Sascha Brune 1 EarthByte Group, School of Geosciences, The University of Sydney, NSW 2006, Australia 2 Helmholtz Centre Potsdam, GFZ German Research Centre for Geosciences, Section 2.5, Geodynamic Modelling, Potsdam, Germany ABSTRACT Rifting between large continental plates results in either continental breakup and the formation of conjugate passive margins or rift abandonment and a set of aborted rift basins. The driving mechanisms behind “successful” or “failed” rifting have so far never been scrutinized by joint kinematic and forward numerical modelling. We analyse the Early Cretaceous extension between Africa and South America which was preceded by about 20-30 Myrs of extensive rifting prior to the final separation between the two plates. While the South and Atlantic conjugate margins continued into seafloor spreading mode, forming the Atlantic ocean basin, Cretaceous-aged African intraplate rifts eventually “failed” soon after South America broke up from Africa. We address the spatio-temporal dynamics of rifting in domains by comparing a new plate kinematic model for the South Atlantic and 3D forward rift models. This joint approach elucidates (1) the dynamic competition of Atlantic and extensional systems, (2) two stage kinematics of the South Atlantic rift system, and (3) the acceleration of the South American plate prior to final break-up. We suggest that obliquity the success of the Equatorial Atlantic rift, ultimately prohibiting the formation of a “Saharan Atlantic Ocean” in the Early Cretaceous, and exerting a primary control on the increase in observed extensional velocities between the South American and African plates. -
SÉRANNE, M., and ANKA, Z., 2005
ARTICLE IN PRESS Journal of African Earth Sciences xxx (2005) xxx–xxx www.elsevier.com/locate/jafrearsci South Atlantic continental margins of Africa: A comparison of the tectonic vs climate interplay on the evolution of equatorial west Africa and SW Africa margins Michel Se´ranne *, Zahie Anka UMR 5573 Dynamique de la Lithosphe`re, CNRS/Universite´ Montpellier 2, 34095 Montpellier cedex 05, France Received 5 February 2005; accepted 18 July 2005 Abstract Africa displays a variety of continental margin structures, tectonic styles and sedimentary records. The comparative review of two representative segments: the equatorial western Africa and the SW Africa margins, helps in analysing the main controlling factors on the development of these margins. Early Cretaceous active rifting south of the Walvis Ridge resulted in the formation of the SW Africa volcanic margin that displays thick and wide intermediate igneous crust, adjacent to a thick unstretched continental crust. The non-vol- canic mode of rifting north of the Walvis ridge, led to the formation of the equatorial western Africa margin, characterised by a wide zone of crustal stretching and thinning, and thick, extensive, syn-rift basins. Contrasting lithologies of the early post-rift (salt vs shale) determined the style of gravitational deformation, whilst periods of activity of the decollements were controlled by sedimentation rates. Regressive erosion across the prominent shoulder uplift of SW Africa accounts for high clastic sedimentation rate during Late Creta- ceous to Eocene, while dominant carbonate production on equatorial western Africa shelf suggests very little erosion of a low hinterland. The early Oligocene long-term climate change had contrasted response in both margins. -
Changing Hillslopes : Evolution and Inheritance
Provided for non-commercial research and educational use only. Not for reproduction, distribution or commercial use. This chapter was originally published in the Treatise on Geomorphology, the copy attached is provided by Elsevier for the author’s benefit and for the benefit of the author’s institution, for non-commercial research and educational use. This includes without limitation use in instruction at your institution, distribution to specific colleagues, and providing a copy to your institution’s administrator. All other uses, reproduction and distribution, including without limitation commercial reprints, selling or licensing copies or access, or posting on open internet sites, your personal or institution’s website or repository, are prohibited. For exceptions, permission may be sought for such use through Elsevier’s permissions site at: http://www.elsevier.com/locate/permissionusematerial Roering J.J., and Hales T.C. Changing Hillslopes: Evolution and Inheritance; Inheritance and Evolution of Slopes. In: John F. Shroder (Editor-in-chief), Marston, R.A., and Stoffel, M. (Volume Editors). Treatise on Geomorphology, Vol 7, Mountain and Hillslope Geomorphology, San Diego: Academic Press; 2013. p. 284-305. © 2013 Elsevier Inc. All rights reserved. Author's personal copy 7.29 Changing Hillslopes: Evolution and Inheritance; Inheritance and Evolution of Slopes JJ Roering, University of Oregon, Eugene, OR, USA TC Hales, Cardiff University, Cardiff, UK r 2013 Elsevier Inc. All rights reserved. 7.29.1 Introduction 285 7.29.2 Hillslope Evolution -
Sea Experience in Developing Countries
Chapter 6 SEA EXPERIENCE IN DEVELOPING COUNTRIES Increasingly, developing countries are experimenting with SEA and some have SEA-type approaches and elements in place already. There is also considerable experience with using a variety of strategic planning processes that display many of the characteristics of SEA (para SEA). We focus first on SEA in southern Africa where a dedicated regional workshop on SEA was organised to feed into this review (SAIEA 2003a), followed by sections covering francophone Africa, the rest of sub-Saharan Africa, Latin America, Asia and elsewhere. But our survey of this field represents no more than a preliminary reconnaissance. Selected examples of SEA and para SEA illustrate some of the indigenous approaches that have been adopted. These are less common than SEAs promoted and funded by development assistance agencies (which are reviewed in Chapter 4). In most cases where formal SEA has been undertaken in developing countries, the basic aim and approach has mirrored that in the north – namely to identify the environmental consequences (and associated social and economic effects) of existing, new or revised policies, plans and programmes. These represent only a small number of the broad family of SEA approaches. But they are a highly visible sub-set of the large suite of informal or para-SEAs which form part of development policy-making, land use planning or resource management. No strict boundaries can be drawn for this latter area of application. Only the more evident SEA type elements and approaches are introduced in this chapter. Nevertheless, they indicate the scope and diversity of the extended SEA family in developing countries, where political and economic realities constrain what can be done. -
Depositional Environment of the Gombe Formation in the Gongola Sub-Basin of the Northern Benue Trough: Using Grain Size Parameters
DOI: http://dx.doi.org/10.4314/gjgs.v15i1.3 GLOBAL JOURNAL OF GEOLOGICAL SCIENCES VOL. 15, 2017: 25-39 COPYRIGHT© BACHUDO SCIENCE CO. LTD PRINTED IN NIGERIA ISSN 1596-6798 25 www.globaljournalseries.com, Email: [email protected] DEPOSITIONAL ENVIRONMENT OF THE GOMBE FORMATION IN THE GONGOLA SUB-BASIN OF THE NORTHERN BENUE TROUGH: USING GRAIN SIZE PARAMETERS M. B. USMAN, Y. D. MAMMAN, U. ABUBAKAR, A. SULAIMAN AND H. HAMIDU (Received 16 June 2016; Revision Accepted 25 July 2016) ABSTRACT The depositional environment of the Gombe Formation was determined using grain size parameters in which sixteen sandstone samples and ninety nine pebbles were subjected to granulometric and pebbles morphometric analysis respectively. The granulometric analysis for the sixteen (16) samples of the Gombe Formation show an average graphic mean of 2.51ϕ (fine grained sandstone), mean standard deviation of 0.58ϕ (moderately well sorted sandstone), mean skewness value of 0.09ϕ (nearly symmetrical) and mean kurtosis value of 0.89ϕ (platykurtic). The Bivariate plot of standard deviation vs. skewness indicated dominance of fluvial environment. While the probability curves plots showed a dominance of three sand populations indicating influence of marine processes. Environmental discrimination formulae for Y1, Y2 and Y3 indicated dominance of Aeolian, shallow agitated marine environment and shallow marine environment respectively. The plots of Y2 vs.Y1 and Y3 vs. Y2 showed a dominance shallow marine environment. The morphometric analysis indicates both fluvial and beach environment with dominance of fluvial environment. KEYWORDS: Gombe Formation, Gongola Sub-Basin, Pebbles Morphology, Granulometric analysis, grain size INTRODUCTION Tukur et al. (2015). -
Geologic Map and Digital Database of the Cougar Buttes 7.5′ Quadrangle, San Bernardino County, California
science for a changing world U. S. DEPARTMENT OF THE INTERIOR OPEN-FILE REPORT U. S. GEOLOGICAL SURVEY 00-175 GEOLOGIC MAP AND DIGITAL DATABASE OF THE COUGAR BUTTES 7.5′ QUADRANGLE, SAN BERNARDINO COUNTY, CALIFORNIA Version 1.0 SUMMARY PAMPHLET: LATE CENOZOIC DEPOSITS OF THE COUGAR BUTTES 7.5′ QUADRANGLE, SAN BERNARDINO COUNTY, CALIFORNIA By Robert E. Powell1 and Jonathan C. Matti2 2000 Prepared in cooperation with Mojave Water Agency California Division of Mines and Geology This database is preliminary and has not been reviewed for conformity with U.S. Geological Survey editorial standards or with the North American Stratigraphic Code. Any use of trade, product, or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Government. U.S. Geological Survey 1 904 W. Riverside Avenue, Spokane, WA 99201-1087 2 520 N. Park Avenue, Tucson, AZ 85719 Open-File Report 00-175, The Geologic Map and Digital Database of the Cougar Buttes 7.5' Quadrangle, San Bernardino County, California, and this summary pamphlet have been approved for release and publication by the Director of the U.S. Geological Survey. The geologic map, digital database, and summary pamphlet have been subjected to rigorous review and are a substantially complete representation of the current state of knowledge concerning the geology of the quadrangle, although the USGS reserves the right to revise the data pursuant to further analysis and review. This Open-File Report is released on the condition that neither the USGS nor the United States Government may be held responsible for any damages resulting from its authorized or unauthorized use. -
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. -
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.........................................................................................................................