Evidence of Rain Shadow in the Geologic Record: Repeated Evaporite Accumulation at Extensional and Compressional Plate Margins
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Geologic Storage Formation Classification: Understanding Its Importance and Impacts on CCS Opportunities in the United States
BEST PRACTICES for: Geologic Storage Formation Classification: Understanding Its Importance and Impacts on CCS Opportunities in the United States First Edition Disclaimer This report was prepared as an account of work sponsored by an agency of the United States Government. Neither the United States Government nor any agency thereof, nor any of their employees, makes any warranty, express or implied, or assumes any legal liability or responsibility for the accuracy, completeness, or usefulness of any information, apparatus, product, or process disclosed, or represents that its use would not infringe privately owned rights. Reference therein to any specific commercial product, process, or service by trade name, trademark, manufacturer, or otherwise does not necessarily constitute or imply its endorsement, recommendation, or favoring by the United States Government or any agency thereof. The views and opinions of authors expressed therein do not necessarily state or reflect those of the United States Government or any agency thereof. Cover Photos—Credits for images shown on the cover are noted with the corresponding figures within this document. Geologic Storage Formation Classification: Understanding Its Importance and Impacts on CCS Opportunities in the United States September 2010 National Energy Technology Laboratory www.netl.doe.gov DOE/NETL-2010/1420 Table of Contents Table of Contents 5 Table of Contents Executive Summary ____________________________________________________________________________ 10 1.0 Introduction and Background -
Rain Shadows
WEB TUTORIAL 24.2 Rain Shadows Text Sections Section 24.4 Earth's Physical Environment, p. 428 Introduction Atmospheric circulation patterns strongly influence the Earth's climate. Although there are distinct global patterns, local variations can be explained by factors such as the presence of absence of mountain ranges. In this tutorial we will examine the effects on climate of a mountain range like the Andes of South America. Learning Objectives • Understand the effects that topography can have on climate. • Know what a rain shadow is. Narration Rain Shadows Why might the communities at a certain latitude in South America differ from those at a similar latitude in Africa? For example, how does the distribution of deserts on the western side of South America differ from the distribution seen in Africa? What might account for this difference? Unlike the deserts of Africa, the Atacama Desert in Chile is a result of topography. The Andes mountain chain extends the length of South America and has a pro- nounced influence on climate, disrupting the tidy latitudinal patterns that we see in Africa. Let's look at the effects on climate of a mountain range like the Andes. The prevailing winds—which, in the Andes, come from the southeast—reach the foot of the mountains carrying warm, moist air. As the air mass moves up the wind- ward side of the range, it expands because of the reduced pressure of the column of air above it. The rising air mass cools and can no longer hold as much water vapor. The water vapor condenses into clouds and results in precipitation in the form of rain and snow, which fall on the windward slope. -
Non-Clastic Sedimentary Rocks by Cindy Grigg
Non-Clastic Sedimentary Rocks By Cindy Grigg 1 Rocks can be put into three main groups. They are grouped by how the rocks formed. Sedimentary (sed-uh-MEN-tuh-ree) rocks are formed on or near Earth's surface. Sedimentary rocks are sorted into other groups. They can be sorted as clastic or non-clastic. This group tells something about the rocks' beginning and what they formed from. 2 Non-clastic rocks are created when water evaporates or from the remains of plants and animals. Limestone is a non-clastic sedimentary rock. Limestone is made of the mineral calcite. It often contains fossils. Limestone formed in the ocean from the shells and skeletons of dead sea creatures. Some of the fossils in limestone are too small to be seen without a microscope. Chalk is a type of limestone that is usually white. It consists almost entirely of the shells of tiny dead sea creatures. Limestone is a common building material. 3 Coal is another non-clastic rock. It formed from the dead remains of plants. Millions of years ago, plants fell into swamps. They were covered with layers of sediment and did not rot. Over millions of years, as the remains were buried deeper under more and more layers of sediment, they were changed by pressure into coal. Coal is commonly used as fuel in power plants to make electricity. 4 Evaporite rocks formed when minerals such as gypsum and halite (rock salt) were left behind as water evaporated from oceans and lakes. Evaporite is common in desert areas, where evaporation is high, such as the Great Salt Lake in Utah. -
CCN Characteristics During the Indian Summer Monsoon Over a Rain- Shadow Region Venugopalan Nair Jayachandran1, Mercy Varghese1, Palani Murugavel1, Kiran S
https://doi.org/10.5194/acp-2020-45 Preprint. Discussion started: 3 February 2020 c Author(s) 2020. CC BY 4.0 License. CCN characteristics during the Indian Summer Monsoon over a rain- shadow region Venugopalan Nair Jayachandran1, Mercy Varghese1, Palani Murugavel1, Kiran S. Todekar1, Shivdas P. Bankar1, Neelam Malap1, Gurunule Dinesh1, Pramod D. Safai1, Jaya Rao1, Mahen Konwar1, Shivsai 5 Dixit1, Thara V. Prabha1, 1Indian Institute of Tropical Meteorology, Pune, India. Correspondence to: V. Jayachandran ([email protected]) Abstract. Continuous aerosol and Cloud Condensation Nuclei (CCN) measurements carried out at the ground observational facility situated in the rain-shadow region of the Indian sub-continent are illustrated. These observations were part of the 10 Cloud-Aerosol Interaction Precipitation Enhancement EXperiment (CAIPEEX) during the Indian Summer Monsoon season (June to September) of 2018. Observations are classified as dry-continental (monsoon break) and wet-marine (monsoon active) according to air mass history. CCN concentrations measured for a range of supersaturations (0.2-1.2 %) are parameterized using Twomey’s empirical relationship. CCN concentrations even at low (0.2 %) supersaturation (SS) were high (>1,000 cm- 3) during continental conditions associated with high black carbon (BC~2,000 ng m-3) and columnar aerosol loading. During 15 the marine air mass conditions, CCN concentrations diminished to ~350 cm-3 at 0.3 % SS and low aerosol loading persisted (BC~900 ng m-3). High CCN activation fraction (AF) of ~0.55 (at 0.3 % SS) were observed before the monsoon rainfall, which reduced to ~0.15 during the monsoon and enhanced to ~0.32 after that. -
National Evaporite Karst--Some Western Examples
122 National Evaporite Karst--Some Western Examples By Jack B. Epstein U.S. Geological Survey, National Center, MS 926A, Reston, VA 20192 ABSTRACT Evaporite deposits, such as gypsum, anhydrite, and rock salt, underlie about one-third of the United States, but are not necessarily exposed at the surface. In the humid eastern United States, evaporites exposed at the surface are rapidly removed by solution. However, in the semi-arid and arid western part of the United States, karstic features, including sinkholes, springs, joint enlargement, intrastratal collapse breccia, breccia pipes, and caves, locally are abundant in evaporites. Gypsum and anhydrite are much more soluble than carbonate rocks, especially where they are associated with dolomite undergoing dedolomitization, a process which results in ground water that is continuously undersaturated with respect to gypsum. Dissolution of the host evaporites cause collapse in overlying non-soluble rocks, including intrastratal collapse breccia, breccia pipes, and sinkholes. The differences between karst in carbonate and evaporite rocks in the humid eastern United States and the semi-arid to arid western United States are delimited approximately by a zone of mean annual precipitation of 32 inches. Each of these two rock groups behaves differently in the humid eastern United States and the semi-arid to arid west. Low ground-water tables and decreased ground water circulation in the west retards carbonate dissolution and development of karst. In contrast, dissolution of sulphate rocks is more active under semi-arid to arid conditions. The generally thicker soils in humid cli- mates provide the carbonic acid necessary for carbonate dissolution. Gypsum and anhydrite, in contrast, are soluble in pure water lacking organic acids. -
Semiarid Ethnoagroforestry Management: Tajos in the Sierra Gorda, Guanajuato, Mexico Vincent M
Hoogesteger van Dijk et al. Journal of Ethnobiology and Ethnomedicine (2017) 13:34 DOI 10.1186/s13002-017-0162-y RESEARCH Open Access Semiarid ethnoagroforestry management: Tajos in the Sierra Gorda, Guanajuato, Mexico Vincent M. Hoogesteger van Dijk1, Alejandro Casas1 and Ana Isabel Moreno-Calles2* Abstract Background: The semi-arid environments harbor nearly 40% of biodiversity, and half of indigenous cultures of Mexico. Thousands of communities settled in these areas depend on agriculture and using wild biodiversity for their subsistence. Water, soil, and biodiversity management strategies are therefore crucial for people’s life. The tajos, from Sierra Gorda, are important, poorly studied, biocultural systems established in narrow, arid alluvial valleys. The systems are constructed with stone-walls for capturing sediments, gradually creating fertile soils in terraces suitable for agriculture in places where it would not be possible. We analyzed biocultural, ecological, economic and technological relevance of the artificial oasis-like tajos, hypothesizing their high capacity for maintaining agricultural and wild biodiversity while providing resources to people. Methods: We conducted our research in three sections of the Mezquital-Xichú River, in three communities of Guanajuato, Mexico. Agroforestry management practices were documented through semi-structured and in-depth qualitative interviews. Vegetation composition of local forests and that maintained in tajos was sampled and compared. Results: Tajos harbor high agrobiodiversity, including native varieties of maize and beans, seven secondary crops, 47 native and 25 introduced perennial plant species. Perennial plants cover on average 26.8% of the total surface of plots. Tajos provide nearly 70% of the products required by households’ subsistence and are part of their cultural identity. -
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. -
S40645-019-0306-X.Pdf
Isaji et al. Progress in Earth and Planetary Science (2019) 6:60 Progress in Earth and https://doi.org/10.1186/s40645-019-0306-x Planetary Science RESEARCH ARTICLE Open Access Biomarker records and mineral compositions of the Messinian halite and K–Mg salts from Sicily Yuta Isaji1* , Toshihiro Yoshimura1, Junichiro Kuroda2, Yusuke Tamenori3, Francisco J. Jiménez-Espejo1,4, Stefano Lugli5, Vinicio Manzi6, Marco Roveri6, Hodaka Kawahata2 and Naohiko Ohkouchi1 Abstract The evaporites of the Realmonte salt mine (Sicily, Italy) are important archives recording the most extreme conditions of the Messinian Salinity Crisis (MSC). However, geochemical approach on these evaporitic sequences is scarce and little is known on the response of the biological community to drastically elevating salinity. In the present work, we investigated the depositional environments and the biological community of the shale–anhydrite–halite triplets and the K–Mg salt layer deposited during the peak of the MSC. Both hopanes and steranes are detected in the shale–anhydrite–halite triplets, suggesting the presence of eukaryotes and bacteria throughout their deposition. The K–Mg salt layer is composed of primary halites, diagenetic leonite, and primary and/or secondary kainite, which are interpreted to have precipitated from density-stratified water column with the halite-precipitating brine at the surface and the brine- precipitating K–Mg salts at the bottom. The presence of hopanes and a trace amount of steranes implicates that eukaryotes and bacteria were able to survive in the surface halite-precipitating brine even during the most extreme condition of the MSC. Keywords: Messinian Salinity Crisis, Evaporites, Kainite, μ-XRF, Biomarker Introduction hypersaline condition between 5.60 and 5.55 Ma (Manzi The Messinian Salinity Crisis (MSC) is one of the most et al. -
Fossil Pollen Records Indicate That Patagonian Desertification Was Not Solely a Consequence of Andean Uplift
ARTICLE Received 25 Oct 2013 | Accepted 4 Mar 2014 | Published 28 Mar 2014 DOI: 10.1038/ncomms4558 Fossil pollen records indicate that Patagonian desertification was not solely a consequence of Andean uplift L. Palazzesi1,2, V.D. Barreda1, J.I. Cuitin˜o3, M.V. Guler4, M.C. Tellerı´a5 & R. Ventura Santos6 The Patagonian steppe—a massive rain-shadow on the lee side of the southern Andes—is assumed to have evolved B15–12 Myr as a consequence of the southern Andean uplift. However, fossil evidence supporting this assumption is limited. Here we quantitatively estimate climatic conditions and plant richness for the interval B10–6 Myr based on the study and bioclimatic analysis of terrestrially derived spore–pollen assemblages preserved in well-constrained Patagonian marine deposits. Our analyses indicate a mesothermal climate, with mean temperatures of the coldest quarter between 11.4 °C and 16.9 °C (presently B3.5 °C) and annual precipitation rarely below 661 mm (presently B200 mm). Rarefied richness reveals a significantly more diverse flora during the late Miocene than today at the same latitude but comparable with that approximately 2,000 km further northeast at mid-latitudes on the Brazilian coast. We infer that the Patagonian desertification was not solely a consequence of the Andean uplift as previously insinuated. 1 Museo Argentino de Ciencias Naturales ‘Bernardino Rivadavia’, Angel Gallardo 470 (C1405DJR), Buenos Aires, Argentina. 2 Jodrell Laboratory, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3DS, UK. 3 Universidad de Buenos Aires, Departamento de Ciencias Geolo´gicas, Facultad de Ciencias Exactas y Naturales. Intendente Gu¨iraldes 2160 (C1428EHA), Buenos Aires, Argentina. -
Seismic Delineation of the Prairie Evaporite Dissolution Edge in South-Central Saskatchewan
Seismic Delineation of the Prairie Evaporite Dissolution Edge in South-central Saskatchewan H. Hamid 1, I.B. Morozov 1, and L.K. Kreis Hamid, H., Morozov, I.B., and Kreis, L.K. (2005): Seismic delineation of the Prairie Evaporite dissolution edge in south-central Saskatchewan; in Summary of Investigations 2005, Volume 1, Saskatchewan Geological Survey, Sask. Industry Resources, Misc. Rep. 2005-4.1, CD-ROM, Paper A-8, 11p. Abstract Approximately 330 km of 2-D seismic data were integrated with well log information to improve the delineation of the southern margin of the Middle Devonian Prairie Evaporite in Saskatchewan. Thirteen seismic lines were re- processed with an emphasis on enhancing high-frequency imaging. The resulting seismic sections show marked improvement in the accuracy and quality of subsurface mapping of the Prairie Evaporite salt edges. Seismic data indicate that salt dissolution structures were created by multistage processes. Thickening of overlying strata related to salt dissolution was observed within both salt-free areas and areas of preserved Prairie Evaporite. Well-log data were combined with seismic results and gridded to create an updated map of the Prairie Evaporite. Different gridding methods provided different interpolations of the data set, especially where the salt layer is thin near its margin. Comparisons with seismic interpretations show that interpolation of well data alone using different interpolation techniques can result in shifts in the delineated position of the salt edges of about 2 to 9 km. Therefore, integration of the seismic and well log data should increase the accuracy of delineating the salt edge. An attempt was also made to determine whether the effect of the salt edge could be observed in gravity data. -
Orographic Control of the Bay of Bengal Cold Pool Rainfall
J. Earth Syst. Sci. (2017) 126:111 c Indian Academy of Sciences https://doi.org/10.1007/s12040-017-0892-1 Orographic control of the Bay of Bengal cold pool rainfall PVArushi1,2,* , Arindam Chakraborty1,2 and Ravi S Nanjundiah1,2,3 1Centre for Atmospheric and Oceanic Sciences, Indian Institute of Science, Bengaluru 560 012, India. 2Divecha Centre for Climate Change, Indian Institute of Science, Bengaluru 560 012, India. 3Indian Institute of Tropical Meteorology, Pune 411 008, India. *Corresponding author. e-mail: [email protected] MS received 24 February 2017; revised 30 May 2017; accepted 30 May 2017; published online 23 November 2017 In boreal summer (June–September), most of the Indian land and its surroundings experience rainrates exceeding 6 mm day−1 with considerable spatial variability. Over southern Bay of Bengal (BoB) along the east coast of the Indian peninsula (henceforth referred to as the Bay of Bengal cold pool or BoB-CP), the rain intensity is significantly lower (<2mmday−1) than its surroundings. This low rainfall occurs despite the fact that the sea surface temperature in this region is well above the threshold for convection and the mean vorticity of the boundary layer is cyclonic with a magnitude comparable to that over the central Indian monsoon trough where the rainrate is about 10 mm day−1. It is also noteworthy that the seasonal cycle of convection over the BoB-CP shows a primary peak in November and a secondary peak in May. This is in contrast to the peak in June–July over most of the oceanic locations surrounding the BoB-CP. -
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People and Place Curriculum Resources on Human-Environmental Interactions Hemispheres is a joint project of: Teresa Lozano Long Institute of Latin American Studies Center for Middle Eastern Studies Center for Russian, East European & Eurasian Studies South Asia Institute in the College of Liberal Arts at The University of Texas at Austin Hemispheres People and Place Curriculum Resources on Human-Environmental Interactions Primary Authors: Natalie Arsenault, Outreach Coordinator Teresa Lozano Long Institute of Latin American Studies Christopher Rose, Outreach Coordinator Center for Middle Eastern Studies Allegra Azulay, Outreach Coordinator Center for Russian, East European & Eurasian Studies Jordan Phillips, Outreach Coordinator South Asia Institute People and Place Curriculum Resources on Human-Environmental Interactions Final Version Original Compilation Date: June 2005 Final Publication Date: April 2007 Permission is granted to reproduce this unit for classroom use only. Please do not redistribute this unit without prior permission. For more information, please see: http://www.utexas.edu/cola/orgs/hemispheres/ Permission to include copyrighted materials in this unit is indicated in citations. TheThe Republic Republic of Sakha (Yakutia)(Yakutia) TEACHER NOTES GOALS This case study will help your students learn about climate and temperature variations, and explore ways that people who live in cold climates have adapted to extreme temperatures. ASSESSMENT EVIDENCE T-Chart Acitivity: Living in Yakutia: Students will consider the pros and cons of living in an extreme environment. LEARNING ACTIVITIES • In the Siberian Curse: An Introduction to Yakutia reading and worksheet, students will learn about the extreme temperatures found in the Republic of Sakha (Yakutia) and consider some of the hardships caused by these temperatures, as well as reasons that people have moved to such a remote area.