DOCSLIB.ORG

Broadening Theories of Soil Genesis: Insights from Tanzania and Simple Models Mark Gabriel Little Doctor of Philosophy

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Broadening Theories of Soil Genesis: Insights from Tanzania and Simple Models Mark Gabriel Little Doctor of Philosophy RICE UNIVERSITY Broadening Theories of Soil Genesis: Insights from Tanzania and Simple Models by Mark Gabriel Little A THESIS SUBMITTED IN PARTIAL FULFILLMENT OF THE REQUIREMENTS FOR THE DEGREE Doctor of Philosophy APPROVED, THESIS COMMITTEE: Cin-Ty ee, Chair, Assistant Professor Earth Science Andreas Liittge, Associ e Professor Earth Science and Chemistry ~~d/Maso~Olh~ Pl"()fussor Civil and Environmental Engineering Jo Anderson, W. Maurice Ewing Pr: essor in Oceanography Earth Science Carrie Masiello, Assistant Professor Earth Science HOUSTON, TEXAS MAY2007 ABSTRACT Broadening Theories of Soil Genesis: Insights from Tanzania and Simple Models by Mark Gabriel Little Three basic assumptions of soil formation are challenged herein: the degree of chemical weathering decreases with depth; increased physical weathering due to high topographical gradients causes an in?rease in chemical weathering; and the mineral soil derives from the transformation of in situ parent material. The first part presents an investigation into the degree and nature of chemical weathering during soil formation on a volcanic substrate on Mt. Kilimanjaro in northern Tanzania. The degree of weathering was found to increase with depth in the soil profile. Observations show that the upper and lower layers of the weathering profile have undergone different weathering histories. The presence of a buried paleosol or enhanced weathering due to lateral subsurface water flow may explain the observations, the latter having novel implications for the transport of dissolved cations to the ocean. The second part presents a model to test the link between chemical weathering associated with soil fmmation and erosion associated with mass wasting. The predicted ratios suspended/dissolved ratios, however, are all higher than observed in rivers, the discrepancy worsening with increasing topographic relief. This discrepancy arises from the fact that in regions of high relief, mass wasting are so high that soil mantles do not reside on hillslopes long enough to allow for significant chemical weathering. The discrepancy between the model and observations can be explained by: over-estimate of predicted suspended load; absence of chemical weathering of deltaic/alluvial sediments from the model; or chemical weathering associated with groundwater weathering. The third part presents data from a sequential extraction on a basaltic soil from Mt. Meru in Northern Tanzania. The behavior of relatively immobile elements is consistent with soil formation being accompanied by mass loss due to chemical weathering. However, superimposed on this mass loss appears to be enrichment of most elements measured. These data suggest that the surface of the Meru soil columns may have experienced "re-fertilization" by the deposition of volcanic ash. ACKNOWLEDGEMENTS In the fall of2003, I arrived in Houston to work with Cin-ty A Lee, the most inquisitive, challenging and creative advisor I could ask for. Cin-ty has shaped my concept of good science and the societal role of the scientist. He has also provided vital research funds and much of my stipend (through departmental funds and a Packard Fellowship). The bulk of my stipend has been generously provided by a Ford Foundation Fellowship and the Office of the President of Rice University. I came to Rice with the support of many former professors including Richard O'Connell, Daniel Schrag, John Shaw, Joseph Kalt and Otto Solbrig at Harvard and my senior thesis advisor, Maria Zuber, from M.I.T. Conversations with my thesis committee, Andreas Liittge, Mason Tomson, John Anderson and Carrie Masiello, have been central to my progress and research. Others have also been wonderful resources: Arnaud Agranier, Philip Bedient, Jim Blackburn, Joe Cibor, Paul Harcombe, Zhengxue Li, Neal Lane, Julie Morgan, Glen Snyder and Carter Sturm. Musa Naroro, Felix John and Nuru and A.S.S. Mbwana, George Sayulla and Rama Ngatoluwa were all invaluable during fieldwork in Tanzania. I am also grateful to the James A. Baker III Institute for Public Policy for providing me a way to engage the Houston community. And I am indebted to my students who inspired me while suffering through my disorganization. Of course, none of this would be possible without my parents, Shade Keys Little and Bernadette Gray-Little, my Grandma Little and all of my antecedents. v TABLE OF CONTENTS 1 TITLE PAGE 11 ABSTRACT lV ACKNOWLEDGEMENTS v TABLE OF CONTENTS 1 INTRODUCTION 5 PART I: On the formation of an inverted weathering profile on Mount Kilimanjaro, Tanzania: buried paleosol or groundwater weathering? 52 PART II: Physical and chemical weathering in mountainous regions: insights from a model linking chemical weathering to soil formation, creep and mass wasting 96 PART III: Element distribution in soils from Mount Meru, Tanzania: a combined bulk and leach study 157 APPENDIX A: Investigating the distribution of labile metals in a vertisol in southeastern Texas 180 APPENDIX B: Bulk composition tables from Mweka, Olmani and Monduli 200 NOTES 202 BIBLIOGRAPHY 1 INTRODUCTION 2 Soils form a thin chemical boundary layer between the oxidizing, wet atmosphere 6 8 and the solid earth. Compared to the radius of the earth (~ 10 · m) or the thickness of the 4 5 2 2 continents (~ 10 · m), soils are relatively thin (~ 10 to 1o- m). As such, soils account for small fraction of the total mass of the planet. However, soils are located at the boundary between the solid and fluid earth and are therefore exceedingly important for a number of processes including the global C02 cycle, sediment supply to the oceans and numerous other human activities including agriculture. The capacity of C02 to retain solar energy in the atmosphere as heat was suggested as early as 1896 by Svente Arhhenius. The recognition of C02 as an important greenhouse gas has become common knowledge as the combustion of fossil fuels has driven an unprecedented rise in atmospheric C02 (UNFCCC, 1998) (Somerville et al., 2007) (Petit et al., 1999). The relationship between C02 and climate on long time scales has been strongly asserted by the correlation of C02 measurements and temperature proxies in the Vostok ice core (Petit et al., 1999). C02 is removed from the atmosphere when silicate rocks are chemically weathered and on long time scales weathering of silicate rocks is the main sink for C02 (Berner, 1995; Berner et al., 1983a). As the by­ product of this process, soils retain the reaction products of chemical weathering reactions and are a record of these processes. Chemical weathering reactions liberate some fraction of every element contained in the protolith. These dissolved elements may be transported to the oceans via rivers. The time averaged flux of dissolved material can be deduced from the composition of the soil mantle when compared to samples of unweathered protolith. Physical weathering, e.g. soil creep and mass wasting, liberates un-dissolved solid material that may also be 3 transported to the ocean via rivers as suspended load. Both the dissolved and suspended fluxes are of interest to the sedimentology community and they are important for marine nutrient supply. Areas of high topographic relief are of particular interest because the major rivers of the world have their source in mountainous regions, mass wasting is correlated with topographic gradients and tectonic uplift has been related to weathering rates (Gaillardet et al., 1999; Millot et al., 2002; Raymo et al., 1988). Soils have direct impact on humans because they provide nutrients and a growth substrate for agriculture. Thus understanding the fate of soil nutrients and soil formation rates are important for agricultural planning in natural systems. Soils are also host to a variety of inorganic elements, e.g. Ph (Othman et al., 1997) that may be pernicious or toxic to humans. Therefore the mobility of elements of health concern is important to human health. In East Africa, soil erosion from overgrazing is a growing problem as population demands stress the agricultural and livestock sectors (Little et al., 2001; Scoones and Toulmin, 1999; Solomon et al., 2000). As the population and agricultural use of volcanic soils in Northern Tanzania increases, information about the nutrient availability as well as the distribution of heavy metals will be come more important (Anderson, 1982; Mlingano et al., 2006). The work presented here addresses aspects of each of these soil-related concerns. The first part presents an investigation into the degree and nature of chemical weathering during soil formation on a volcanic substrate on Mt. Kilimanjaro in northern Tanzania. The degree of weathering was found to increase with depth in the soil profile. Observations show that the upper and lower layers of the weathering profile have undergone different weathering histories. The presence of a buried paleosol or enhanced 4 weathering due to lateral subsurface water flow may explain the observations, the latter having novel implications for the transport of dissolved cations to the ocean. The second part presents a model to test the link between chemical weathering associated with soil formation and erosion associated with mass wasting. The predicted ratios suspended/dissolved ratios, however, are all higher than observed in rivers, the discrepancy worsening with increasing topographic relief. This discrepancy arises from the fact that in regions of high relief, mass wasting are so high that soil mantles do not reside on hillslopes long enough to allow for significant chemical weathering. The
Load more

Recommended publications
  • Oral to Written Evidence II
    File No. OF-Fac-Oil-N304-2010-01 01 Hearing Order OH-4-2011 Enbridge Northern Gateway Pipelines Limited Partnership Northern Gateway Dual Pipelines, Tank Farm, and Supertanker Port Proposal *Supplemental Written Evidence Photographic Evidence Regarding Proposed Liquid Petroleum Pipelines from Nimbus Mountain to the Kitimat River Estuary *Originally intended to be submitted during oral evidence community hearings in Kitamaat, BC, on January 11th, 2012. The Panel, in file number A2K5I2, decided the following photographic evidence is considered written evidence, and should be submitted as such. I reserve the right to present this evidence orally at a later date. Hearing Order OH-4-2011 File No. OF-Fac-Oil-N304-2010-01 01 Submitted by Murray Minchin of DOUGLAS CHANNEL WATCH (All website links as of January 6, 2012) INTRODUCTION i.1) The geologic hazards in the Hoult Creek and upper Kitimat River Valleys, the earthflows in the main Kitimat Valley, and the extreme weather events experienced on the western side of the Coast Mountains on British Columbia's north coast may be the Achille's heel of Northern Gateway Pipeline Limited Partnership's proposal to move liquid petroleum products between Alberta's Tar Sands, and tidewater at Kitimat, BC. i.2) The majority of liquid petroleum pipelines in North America are to be found east of the Rocky Mountains in a relatively benign, rolling landscape. i.3) The Hoult Creek and upper Kitimat River Valleys are over 4,700 feet deep, very narrow, and are subject to long lived and extremely moist weather systems coming off the Pacific Ocean.
    [Show full text]
  • Mass-Wasting, Classification and Damage in Ohio C
    MASS-WASTING, CLASSIFICATION AND DAMAGE IN OHIO C. N. SAVAGE Department of Geography and Geology, Kent State University, Kent, Ohio The sudden and often spectacular free fall, slide, flow, creep or subsidence of earth materials may be costly in terms of human lives and property damage. Phenomena of this type, variously called "landslide, earthflow or subsidence" are assigned by geologists to gravity controlled movement or referred to collectively as "mass-wasting." This category also includes movement of dry or hard-frozen masses, or snow-laden debris when moved by gravity. Figure 1 illustrates some of these types of movement. This paper is intended to bring to the attention of laymen and professional men the importance and widespread occurrence of these destructive forces. A brief discussion of damage, origin, prevention and classification is presented, followed by examples in Ohio. It is hoped that the suggested classification will prove useful as an aid to the recognition of different types of mass-movement. Annually, many highways are blocked or destroyed, soils are ruined and buried in rubble, forest lands are ripped apart, and bridges, dams, buildings and other structures are wrecked or buried by landslides. Every year, especially in southern and eastern Ohio, many thousands of dollars are lost because of this type of calamity. There is scarcely a spring which does not bring reports of landslides in the local press. It seems obvious that this is a subject of grave concern to construction engineers, soils experts, conservation men and many others including the tax paying citizen. Wherever there are slopes that are steep enough, and wherever there is loose rock material, mass-wasting is a potential threat.
    [Show full text]
  • Quaternary Geologic Map of the Jackson 7.5–Minute Quadrangle, Eastern Kentucky
    DRAFT GEOLOGIC QUADRANGLE # JACKSON QUADRANGLE, KY. # * Series XII, 2010 GQ-205 Version 1.0 CORRELATION OF MAP UNITS 83°30'00" 83°22'30" GEOLOGIC SUMMARY @ * 37°37'30" 37°37'30" * # 42 GEOTECHNICAL BEHAVIOR * ! 19 GEOLOGIC SETTING Qc Qr Qc @ ( Qal Qls The Jackson 7.5-minute quadrangle is located in Breathitt and Wolfe Counties, Ky., Major properties of surficial materials recorded during mapping include (1) moisture, * Qafp Qc Qca Qr @ * ! Qaf and lies on the western margin of the Eastern Kentucky Coal Field of the Appalachian Basin. texture, Munsell color, and soil structure using standard USDA Soil Survey (Soil Survey # 0 @ Qc Qr Qr Holocene Manual, 1993) terms defined by percentages of sand, silt, and clay and (2) field identification ( @ * This map shows the distribution of surficial, engineering soils above bedrock and the @ ! Qat @ QUATERNARY based on the Unified Soil Classification System (Standard Practice for Description and @ relationship between the surficial geology and the underlying bedrock. The bedrock geology af2 @ Qc Qaf @ consists of gently dipping sedimentary rocks of Pennsylvanian age. These rocks are dominantly Identification of Soils, 1993) for soil properties as cohesion, consistency, plasticity, and af3 dilatancy. This data is from field inspection and is useful for preliminary consideration of how 7 @ @ UNCONFORMITY sandstone, siltstone, shale, coal, and limestone of the Breathitt Group and the Corbin ( af2 @ Qat @ 20 Sandstone. In place sandstone bedrock caps many hilltops and forms steep scarps. Siltstone and surficial deposits may behave during natural or human processes. This data is stored in a 0 (** geodatabase at Kentucky Geological Survey. (www.uky.edu/KGS) ( Qaf shale typically form gentle slopes or when capped by sandstone form eroded rock faces set Qc Qafp # Pz back under the sandstone portion of the exposures.
    [Show full text]
  • Oldhamls Lost Fault
    Oldham’s Lost Fault Oldham’s Kashmir fault was the more enigmatic of the two he describes in the following paragraphs: by Roger Bilham, Bikram Singh Bali, Shabir Ahmad, A curious feature may be observed near the head of this and Celia Schiffman tributary. On the hillside there is a sudden step or bank, commencing gradually and reaching a height of about six to eight feet; it runs along the hill side with a general INTRODUCTION course to W15°N, coinciding with the strike of the beds, but V-ing to the south in the valleys. It crosses the head In 1888 R. D. Oldham, the seismologist best known for first of the next tributary, and in two of the minor drainage quantifying the diameter of the Earth’s core using seismic depressions which are not large enough to have a defined waves, provided a description of the surface rupture of an active stream-bed, it has formed small hollows in which water fault at the southeast end of the Kashmir Valley. Intriguingly, appears to rest after heavy rain. On the watershed be- he described it as a normal fault parallel to the strike of the tween the Shingam and Rajparan drainages it appears trend of the Himalaya, with 2 m of slip that had impounded as a sudden step on the ridge, rendered more conspicuous several sag ponds. He provided no map of its location, and the by a talus bare of vegetation which contrasts strongly fault is not shown on recent maps, nor is it described by later with the grass-clad slopes on either side.
    [Show full text]
  • Special Report 142, 1980. Geology and Slope Stability in Selected
    GEOLOGY AND SLOPE STABILITY IN SELECTED PARTS OF THE GEYSERS GEOTHERMAL RESOURCES AREA: A Guide to Geologic Features Indicative of Stable and Unstable Terrain in Areas Underlain by Franciscan and Related Rocks 1980 CALIFORNIA DIVISION OF MINES AND GEOLOGY SPECIAL REPORT 142 STATE OF CALIFORNIA EDMUND G. BROWN JR. GOVERNOR THE RESOURCES AGENCY HUEY D. JOHNSON SECRETARY FOR RESOURCES DEPARTMENT OF CONSERVATION PRISCILLA C. GREW DIRECTOR DIVISION OF MINES AND GEOLOGY JAMES F. DAVIS STA TE GEOLOGIST SPECIAL REPORT 142 GEOLOGY ,AND SLOPE STABILITY IN SELEO'ED PARTS OF THE GEYSERS GEOTHERMAL RESOURCES AREA: A Guide to Geologic Features Indicative of Stable and Unstable Terrain in Areas Underlain by Franciscan and Related Rocks By Trinda L. Bedrossian Geologist 1980 CALIFORNIA DIVISION OF MINES AND GEOLOGY 1416 Ninth Street, Room 1341 Sacramento, CA 95814 -~------------------------------------------------------------------------------------------------------------------- CONTENTS Page SUMMARY OF FINDINGS ........................................~ ...................................................................................................................1 RECOMMENDATIONS ..................................................................................................................................................................1 INTRODUCTION· ............................................................................................................................................................................2 Purpose and scope ....................................•....•................•........................•....•..........•...............
    [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]
  • 56039.Pdf (7.370Mb)
    MECHANISMS OF DOWNHILL CREEP IN EXPANSIVE SOILS A Dissertation by Lawrence Dana Dyke Submitted to the Graduate College of Texas A&M University in partial fulfillment of the requirement for the degree of DOCTOR OF PHILOSOPHY December 1979 Major Subject: Geology MECHANISMS OF DOWNHILL CREEP IN EXPANSIVE SOILS A Dissertation by Lawrence Dana Dyke Approved as to style and content by: r.cTrUf^^. (Chairman of Committee) December 1979 1497741 m ABSTRACT MECHANISMS OF DOWNHILL CREEP IN EXPANSIVE SOILS (December, 1979) Lawrence Dana Dyke, B.S., University of British Columbia M.S., Texas A&M University Chairman of Advisory Committee: Dr. C. C. Mathewson A detailed survey of two tracts of houses on sloping terrain under¬ lain by expansible clay-rich soils indicates that expansive soils are especially susceptible to downhill creep. This poses an additional threat on top of the already well recognized problem of expansive soil damage to light structures. The sites are located in Waco on the South Bosque shale and in San Antonio on the Houston Black clay. Increases in the plasticity index, slope and age all favour increasing damage in Waco and the creep motions preferentially induce cracking on the sides of the houses parallel to the slope. Little dependence on age or slope at the San Antonio site indicates downhill creep is not an important factor there. A study of volume changes vs. soil water potential verifies that a difference exists in mechanical behavior between the soils of the two sites. Both soils exhibit a sudden increase in water content at a low soil water potential as the potential is decreased from -15 bars.
    [Show full text]
  • What Is Mass Movement (Slope Movement)?
    What is mass movement (slope movement)? What is mass movement (slope movement)? Lesson plan (Polish) Lesson plan (English) What is mass movement (slope movement)? Source: licencja: CC 0, [online], dostępny w internecie: pixabay.com. Link to the lesson Before you start you should know what are the most important minerals; what types of rocks are typically found and what are their formation conditions; You will learn how to define and describe weathering processes; to distinguish different types of weathering; to notice how dangerous may mass movement be. Nagranie dostępne na portalu epodreczniki.pl nagranie abstraktu On the basis of the textbook write the definitions of the following terms. Topple Landslide Flow Creep Mass movement (mass wasting, slope movement) may occur in any place with inclined land which means majority of land. Loose rocks and products of weathering may move down the slope, influenced by gravitational force. For the movement to occur, there need to be some factors disturbing balance, hitherto maintained along the slope. These may include natural causes, such as seismic shocks, rain, snow, weathering or river wearing away base of the slope. Some movement may be caused by human activity: overloading slopes with any buildings or cutting through inclined landforms by building roads, railways etc. In steep mountains or at some shores, rocks move down suddenly, sometimes even losing contact with the ground below (topple, rockfall). On slopes with lesser inclination, superficial layer of weathered rocks may slip down very slowly (soil creeping) or abruptly if strong liquid precipitation occurs mud flow. There is also a frequent mass movement called landslide.
    [Show full text]
  • Douglas Channel Photo Evidence
    Attachment 5 to Northern Gateway Reply Evidence AMEC Environment & Infrastructure, a Division of AMEC Americas Limited Suite 600 – 4445 Lougheed Highway, Burnaby, BC Canada V5C 0E4 Tel +1 (604) 294-3811 Fax +1 (604) 294-4664 www.amec.com Geotechnical Response to Photographic Evidence Regarding Proposed Liquid Petroleum Pipelines from Nimbus Mountain to the Kitimat River Estuary Submitted by Murray Minchin of Douglas Channel Watch Proposed Northern Gateway Pipelines Submitted to: NORTHERN GATEWAY PIPELINES INC. Calgary, Alberta Submitted by: AMEC Environment & Infrastructure, a Division of AMEC Americas Limited Burnaby, BC July 17, 2012 AMEC File: EG0926008 2100 100 Document Control No.: 1167-RE-20120716 7054206_2|CALDOCS Attachment 5 to Northern Gateway Reply Evidence Northern Gateway Pipelines Geotechnical Response to Photographic Evidence of Douglas Channel Watch Proposed Northern Gateway Pipelines July 17, 2012 TABLE OF CONTENTS Page 1.0 INTRODUCTION ................................................................................................................ 1 2.0 GEOTECHNICAL RESPONSES ........................................................................................ 2 3.0 LIMITATIONS AND CLOSURE ....................................................................................... 63 REFERENCES ......................................................................................................................... 64 AMEC File: EG0926008 2100 100 G:\PROJECTS\Other Offices\EG-Edmonton\EG09260 - Enbridge Gateway\2100 - Hearings\Douglas
    [Show full text]
  • Slow Denudation Within an Active Orogen: Ladakh Range, Northern India
    Slow denudation within an active orogen: Ladakh Range, Northern India A thesis submitted to the Graduate School of the University of Cincinnati in partial fulfillment of the requirements for the degree of Master of Science in the Department of Geology of the College of Arts and Sciences 2011 by Scott A. Reynhout B.S., Beloit College, 2008 Committee Members: Craig Dietsch, Ph.D. (chair) Lewis A. Owen, Ph.D. Marc W. Caffee, Ph.D. i ABSTRACT Cosmogenic 10Be measurements of both bedrock and basin denudation reveal strong topographic-climatic control on erosion within the Ladakh Range of northwestern India. Bedrock weathering rates, extremely slow below the contemporary equilibrium line altitude, increase by an order of magnitude at the high-elevation range divide. Along the southern slope of the Range south of the range divide, rates of ridge crest summit lowering vary from 0.02±0.03 m/Myr to 0.7±0.09 m/Myr, whereas rates of range divide summit lowering vary from 4.97±0.45 m/Myr to 13.13±1.17 m/Myr. Long-term denudation rates of nonglaciated basins are the lowest yet reported. Accelerated glacial and periglacial erosion near the range divide drives a “frost buzzsaw” in this region that works to selectively destroy high topography. The actively-eroding glacial landscape stands in stark contrast to hillslopes at lower elevations, which have achieved long-term, near equilibrium conditions and may represent extant Pliocene or older landscapes. ii iii ACKNOWLEDGEMENTS SAR thanks the Geological Society of America for funding this research through the 2009 Arthur D.
    [Show full text]
  • Geologic Map of the Pagosa Springs 7.5' Quadrangle, Archuleta County, Colorado
    109° 108° 107° 106° 105° 40° DENVER Gypsum iver o R ad or ol C GeologicGrand Map of the Pagosa SpringsAspen 7.5' Quadrangle, Junction Arkansas River ArchuletaGRAND County, Colorado 39° MESA Colorado Springs UNCOMPAHGRE PLATEAU Montrose Gunnison Pueblo SAN 38° SAN JUAN Rio Grande DOME JUAN SAN LUIS Pagosa Springs Quadrangle MOUNTAINS Alamosa Durango ARCHULETA IN RIM BAS AN Trinidad JU N VALLEY SA 37° COLORADO NEW MEXIO ANTICLINORIUM Farmington BRAZOS UPLIFT CHAMA BASIN NACIMIENTO Pamphlet to accompany UPLIFT 36° VALLES CALDERA ScientificSAN JUAN Investigations BASIN Map 3419 SANGRE DE CRISTO MOUNTAINS SANTA FE U.S. Department of the Interior GallupU.S. Geological Survey Rio Grande Albuquerque 0 30 60 MILES 35° 0 30 60 KILOMETERS Cover. Photograph showing town of Pagosa Springs, Colo. The low terraces are north of town, and Pagosa Peak is on skyline. Taken about 2 miles south of Pagosa Springs, just outside of southern map area border, looking north. Photograph by David Moore, 1980. Geologic Map of the Pagosa Springs 7.5' Quadrangle, Archuleta County, Colorado By David W. Moore and David J. Lidke Pamphlet to accompany Scientific Investigations Map 3419 U.S. Department of the Interior U.S. Geological Survey U.S. Department of the Interior RYAN K. ZINKE, Secretary U.S. Geological Survey James F. Reilly II, Director U.S. Geological Survey, Reston, Virginia: 2018 For more information on the USGS—the Federal source for science about the Earth, its natural and living resources, natural hazards, and the environment—visit https://www.usgs.gov or call 1–888–ASK–USGS. For an overview of USGS information products, including maps, imagery, and publications, visit https://store.usgs.gov.
    [Show full text]
  • Geology for Environmental Planning in the Johnson-Hardwick Region, Vermont
    GEOLOGY FOR ENVIRONMENTAL PLANNING IN THE JOHNSON-HARDWICK REGION, VERMONT BT FRANK M. WRIGHT, III VERMONT GEOLOGIC SURVEY Charles G. Doll, Slate (,ealo gist "... I~. -to -; to WATER RESOURCES DEPARTMENT MONTPELIER, VERMONT ENVIRONMENTAL (;EOLO(;Y NO. 4 1974 TABLE OF CONTENTS Page INTRODUCTION 7 Sources of Material g Explanation of the Planning Maps .............. 10 GEOLOGIC SETTING ................... 10 Green Mountains .................... 11 Vermont Piedmont ................... 11 Drainage ....................... 11 The Bedrock Complex .................. 14 Surficial Materials .................... 15 CLEAN WATER - A NATURAL RESOURCF. .......... 17 Surface Waters ..................... 18 Ground water ..................... 21 WASTES OF A SOCIETY .................. 31 Solid Waste Disposal ................... 2 Sewage Disposal .................... 36 LAND USE AND FUTURE DEVELOPMENT .......... 40 General Construction Conditions .............. 41 Geologic Resources ................... 43 NATURAL HAZARDS ................... 48 Landslides ...................... 49 Flash Floods ..................... 49 ACKNOWLEDGMENTS .................. 55 REFERENCES ...................... 56 APPENDIX A - MAPS SHOWING FIELD LOCATIONS OF SEISMIC PROFILES ................... 60 LIST OF ILLUSTRATIONS Page FIGURE 1. Index map showing where environmental geology studies have been completed ............... 6 FIGURE 2. Index map showing townships, cities and villages in the John- son-Hardwick Region ............... 8 FIGURE 3. Field interpretation of seismic record
    [Show full text]