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1

Space Weathering of Rocks  

NASA Technical Reports Server (NTRS)

Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. On the Moon, rocks make up only a very small percentage of the exposed surface and areas where rocks are exposed, like central peaks, are often among the least space weathered regions we find in remote sensing data. However, our studies of weathered Ap 17 rocks 76015 and 76237 show that significant amounts of weathering products can build up on rock surfaces. Because rocks have much longer surface lifetimes than an individual soil grain, and thus record a longer history of exposure, we can study these products to gain a deeper perspective on the weathering process and better assess the relative impo!1ance of various weathering components on the Moon. In contrast to the lunar case, on small asteroids, like Itokowa, rocks make up a large fraction of the exposed surface. Results from the Hayabusa spacecraft at Itokowa suggest that while the low gravity does not allow for the development of a mature regolith, weathering patinas can and do develop on rock surfaces, in fact, the rocky surfaces were seen to be darker and appear spectrally more weathered than regions with finer materials. To explore how weathering of asteroidal rocks may differ from lunar, a set of ordinary chondrite meteorites (H, L, and LL) which have been subjected to artificial space weathering by nanopulse laser were examined by TEM. NpFe(sup 0) bearing glasses were ubiquitous in both the naturally-weathered lunar and the artificially-weathered meteorite samples.

Noble, Sarah

2011-01-01

2

Rocks and Weathering  

NSDL National Science Digital Library

Sedimentary, igneous and metamorphic rocks, weathering, erosion and transport, and the rock cycle are explained in this resource for students through written content, interactive content, audio, video and games. A multiple choice test is included. Students may score their tests and the correct responses will be given.

3

Rocks, Weathering, and Erosional Landscapes  

NSDL National Science Digital Library

Students will identify principal rock forming silicate minerals and distinguish their relative stability when exposed to weathering; identify sedimentary, igneous and metamorphic rocks and deduce the relative resistance based on mineral composition and texture;and finally relate erosional landscapes to the differential weathering and erosion of rocks of varying strengths. Designed for a geomorphology course

Hanson, Lindley

4

Space Weathering of Lunar Rocks  

NASA Technical Reports Server (NTRS)

All materials exposed at the lunar surface undergo space weathering processes. On the Moon, boulders make up only a small percentage of the exposed surface, and areas where such rocks are exposed, like central peaks, are often among the least space weathered regions identified from remote sensing data. Yet space weathered surfaces (patina) are relatively common on returned rock samples, some of which directly sample the surface of larger boulders. Because, as witness plates to lunar space weathering, rocks and boulders experience longer exposure times compared to lunar soil grains, they allow us to develop a deeper perspective on the relative importance of various weathering processes as a function of time.

Noble, S. K.; Keller, L. P.; Christoffersen, R.; Rahman, Z.

2012-01-01

5

The Weathering of Rocks: Three Activities.  

ERIC Educational Resources Information Center

Integrates science and social studies in several activities that study weathering caused by the freezing and thawing of rocks, wind erosion, and the effects of weathering on tombstones. Cites the possibility of these activities leading to an interdisciplinary exploration of pollution, customs, and populations. (MCO)

McLure, John W.

1991-01-01

6

Modeling rock weathering in small watersheds  

NASA Astrophysics Data System (ADS)

Many mountainous watersheds are conceived as aquifer media where multiple groundwater flow systems have developed (Tóth, 1963), and as bimodal landscapes where differential weathering of bare and soil-mantled rock has occurred (Wahrhaftig, 1965). The results of a weathering algorithm (Pacheco and Van der Weijden, 2012a, 2014), which integrates topographic, hydrologic, rock structure and chemical data to calculate weathering rates at the watershed scale, validated the conceptual models in the River Sordo basin, a small watershed located in the Marão cordillera (North of Portugal). The coupling of weathering, groundwater flow and landscape evolution analyses, as accomplished in this study, is innovative and represents a remarkable achievement towards regionalization of rock weathering at the watershed scale. The River Sordo basin occupies an area of approximately 51.2 km2 and was shaped on granite and metassediment terrains between the altitudes 185-1300 m. The groundwater flow system is composed of recharge areas located at elevations >700 m, identified on the basis of ?18O data. Discharge cells comprehend terminations of local, intermediate and regional flow systems, identified on the basis of spring density patterns, infiltration depth estimates based on 87Sr/86Sr data, and spatial distributions of groundwater pH and natural mineralization. Intermediate and regional flow systems, defined where infiltration depths >125 m, develop solely along the contact zone between granites and metassediments, because fractures in this region are profound and their density is very large. Weathering is accelerated where rocks are covered by thick soils, being five times faster relative to sectors of the basin where rocks are covered by thin soils. Differential weathering of bare and soil-mantled rock is also revealed by the spatial distribution of calculated aquifer hydraulic diffusivities and groundwater travel times.

Pacheco, Fernando A. L.; Van der Weijden, Cornelis H.

2014-05-01

7

Deeply weathered basement rocks in Norway  

NASA Astrophysics Data System (ADS)

Recent studies show that, in addition to tectonic processes, surface processes have also had a profound impact on the topography of Norway. This is especially obvious for the northernmost part of the Nordland county and for western Norway, where the current immature Alpine-type topography cannot be easily explained by tectonic processes only. Erosion of the sedimentary succession also does not seem sufficient to explain the observed relief. Common remnants of deeply weathered basement rocks, however, indicate a history of deep alteration and later erosion of the bedrock, which needs to be considered as another important factor in the development of the topographic relief. Most of the sites with deeply weathered basement exhibit a clay-poor grussy type of weathering, which is generally considered to be of relatively young age (Plio-/Pleistocene) and thought to represent an intermediate stage of weathering. Unfortunately, small amounts or complete absence of clay minerals in these weathering products precluded the accurate dating of this weathered material. Scandinavia was exposed to a large range of glaciations and the once extensive sedimentary successions have been almost entirely eroded, which impedes a minimum age estimate of the weathering profile. Although several sites preserving remnants of deep weathering can still be observed onshore Norway, they are all covered by Quaternary overburden and the age of the regolith remains thus unconstrained and a matter of debate. The only exception is a small Mesozoic basin on Andøya, northern Norway, where weathered and clay-poor saprolite was found underlying Jurassic and Cretaceous sedimentary rocks. Over the last few years the Geological Survey of Norway (NGU) has mapped and investigated deep weathering onshore Norway to better understand weathering processes and to constrain the age of the weathering remnants. The combined interpretation of geophysical, mineralogical and geochemical data, together with recent observations from the Norwegian shelf, where grussy type of weathered bedrock was found buried under Mesozoic sediments, leads to the conclusion that coarse-grained, clay-poor saprolite does not necessarily indicate a young age of weathering but could in fact be of Early Mesozoic age or even older. The Late Jurassic to Early Cretaceous faults in the Lofoten-Vesterålen area are for instance little affected by weathering processes. With the goal to refine our understanding of the complex weathering processes and to constrain them in time, the NGU is establishing a new K-Ar laboratory for the dating and characterization of illite grown authigenically in the saprolites. It is expected that the data generated therein will contribute new quantitative constraints to the long-lasting debate as to the age of weathering processes in Scandinavia.

Bönner, Marco; Knies, Jochen; Fredin, Ola; Olesen, Odleiv; Viola, Giulio

2014-05-01

8

Building Stone and Its Use in Rock Weathering Studies.  

ERIC Educational Resources Information Center

Building stone provides opportunities for geological study of weathering of different rocks in a particular environment and similar rocks in different environment. The principle studied can be applied on a large scale from the observation of small-scale weathering. Examples of weathering are drawn mainly from the Sydney region of Australia. (RE)

Dragovich, Deirdre

1979-01-01

9

Take a Tumble: Weathering and Erosion Using a Rock Tumbler  

ERIC Educational Resources Information Center

Weathering--the physical and chemical breakdown of geologic materials--and erosion--the transport of materials by wind, water, or ice--can be subtle, yet powerful forces. For example, shale, a rock made of mud-sized particles, is by far the most common sedimentary rock, a testament to the ability of weathering and erosion to take a rock and reduce…

Coffey, Patrick; Mattox, Steve

2006-01-01

10

Water Rock Interaction [WRI 14] Chemical weathering of granitic rocks: experimental approach and Pb-Li  

E-print Network

Water Rock Interaction [WRI 14] Chemical weathering of granitic rocks: experimental approach and Pb of water/rock interactions both in terms of source and extent of weathering, by measuring major and trace elements as well as Pb and Li isotope signatures. Keywords: weathering; granite; Pb isotopes; Li isotopes 1

Paris-Sud XI, Université de

11

Draft Genome Sequence of Rhizobium sp. H41, a Rock-Weathering Bacterium from a Weathered Rock Surface  

PubMed Central

Rhizobium sp. H41 isolated from weathered tuff can weather tuff and release Fe, Si, and Al from the rock under nutrient-poor conditions. Here, we report the draft genome sequence of strain H41, which may facilitate a better understanding of the molecular mechanism involved in rock weathering by the bacterium. PMID:25377707

Xi, Jun; He, Linyan

2014-01-01

12

Draft Genome Sequence of Rhizobium sp. H41, a Rock-Weathering Bacterium from a Weathered Rock Surface.  

PubMed

Rhizobium sp. H41 isolated from weathered tuff can weather tuff and release Fe, Si, and Al from the rock under nutrient-poor conditions. Here, we report the draft genome sequence of strain H41, which may facilitate a better understanding of the molecular mechanism involved in rock weathering by the bacterium. PMID:25377707

Xi, Jun; Sheng, Xiafang; He, Linyan

2014-01-01

13

Rock-weathering rates as functions of time  

USGS Publications Warehouse

The scarcity of documented numerical relations between rock weathering and time has led to a common assumption that rates of weathering are linear. This assumption has been strengthened by studies that have calculated long-term average rates. However, little theoretical or empirical evidence exists to support linear rates for most chemical-weathering processes, with the exception of congruent dissolution processes. The few previous studies of rock-weathering rates that contain quantitative documentation of the relation between chemical weathering and time suggest that the rates of most weathering processes decrease with time. Recent studies of weathering rinds on basaltic and andesitic stones in glacial deposits in the western United States also clearly demonstrate that rock-weathering processes slow with time. Some weathering processes appear to conform to exponential functions of time, such as the square-root time function for hydration of volcanic glass, which conforms to the theoretical predictions of diffusion kinetics. However, weathering of mineralogically heterogeneous rocks involves complex physical and chemical processes that generally can be expressed only empirically, commonly by way of logarithmic time functions. Incongruent dissolution and other weathering processes produce residues, which are commonly used as measures of weathering. These residues appear to slow movement of water to unaltered material and impede chemical transport away from it. If weathering residues impede weathering processes then rates of weathering and rates of residue production are inversely proportional to some function of the residue thickness. This results in simple mathematical analogs for weathering that imply nonlinear time functions. The rate of weathering becomes constant only when an equilibrium thickness of the residue is reached. Because weathering residues are relatively stable chemically, and because physical removal of residues below the ground surface is slight, many weathering features require considerable time to reach constant rates of change. For weathering rinds on volcanic stones in the western United States, this time is at least 0.5 my. ?? 1981.

Colman, S. M.

1981-01-01

14

On the weathering of Martian igneous rocks  

NASA Technical Reports Server (NTRS)

Besides the young crystallization age, one of the first arguments for the martian origin of shergottite, nakhlite, and chassignite (SNC) meteorites came from the chemical similarity of the meteorite Shergotty and the martian soil as measured by Viking XRF analyses. In the meantime, the discovery of trapped rare gas and nitrogen components with element and isotope ratios closely matching the highly characteristic ratios of the Mars atmosphere in the shock glasses of shergottite EETA79001 was further striking evidence that the SNC's are martian surface rocks. The martian soil composition as derived from the Viking mission, with its extremely high S and Cl concentrations, was interpreted as weathering products of mafic igneous rocks. The low SiO2 content and the low abundance of K and other trace elements in the martian soils point to a mafic crust with a considerably smaller degree of fractionation compared to the terrestrial crust. However, the chemical evolution of the martian regolith and soil in respect to surface reaction with the planetary atmosphere or hydrosphere is poorly understood. A critical point in this respect is that the geochemical evidence as derived from the SNC meteorites suggests that Mars is a very dry planet that should have lost almost all its initially large water inventory during its accretion.

Dreibus, G.; Waenke, H.

1992-01-01

15

Treatment for a fully weathered rock dam foundation  

Microsoft Academic Search

The main dam at the upper reservoir of Tianhuanping pumped storage power station is a rockfill dam with an asphalt concrete impervious lining on the upstream face. It is constructed on a non-homogeneous fully weathered rock foundation. In this paper, we present the case study on the treatment for this non-homogeneous fully weathered rock dam foundation. The treatment includes the

Y. S. Wang; S. H. Liu

2005-01-01

16

Science Sampler: Chemical weathering--Where did the rocks go?  

NSDL National Science Digital Library

This lesson is part of a larger Earth science unit that combines the concepts of the rock cycle and the water cycle and how they interact to change landforms. The authors refer to it as the "make it and then break it" unit. They spend half the unit making metamorphic, sedimentary, and igneous rock models, and the second half of the unit weathering and eroding their models and other rocks. Students use the lessons learned to answer an open-ended question describing the process of weathering. They also make decisions regarding the chemical and mechanical weathering on monuments and buildings.

Wallace, Carolyn; Zawicki, Joseph; Harris, Robin

2008-10-01

17

Bacillus qingshengii sp. nov., a rock-weathering bacterium isolated from weathered rock surface.  

PubMed

A novel type of rock-weathering bacterium was isolated from weathered rock (tuff) surface collected from Dongxiang (Jiangxi, eastern China). Cells of strain G19(T) were Gram-reaction-positive, rod-shaped, endospore-forming and non-motile. The strain was aerobic, catalase- and oxidase-positive, and grew optimally at 30 °C and pH 7.0. On the basis of 16S rRNA gene sequence analysis, strain G19(T) was shown to belong to the genus Bacillus and the closest phylogenetic relatives were Bacillus aryabhattai B8W22(T) (97.4%) and Bacillus megaterium IAM 13418(T) (97.1%). The DNA G+C content was 36.7 mol% and the predominant respiratory quinone was MK-7. The major fatty acids were iso-C14 : 0, iso-C15 : 0 and anteiso-C15 : 0. The polar lipid profile of strain G19(T) contained phosphatidylglycerol, phosphatidylethanolamine, diphosphatidylglycerol and an unidentified lipid. Based on the low level of DNA-DNA relatedness (ranging from 49.4% to 55.0%) to these type strains of species of the genus Bacillus and unique phenotypic characteristics, strain G19(T) represents a novel species of the genus Bacillus, for which the name Bacillus qingshengii sp. nov. is proposed. The type strain is G19(T) (?= CCTCC AB 2013273(T)?= JCM 19454(T)). PMID:24801156

Xi, Jun; He, Lin-Yan; Huang, Zhi; Sheng, Xia-Fang

2014-07-01

18

Weathering  

NSDL National Science Digital Library

This course handout covers the processes and effects of weathering. The purpose of this handout is to contrast weathering and erosion, contrast and discuss chemical and mechanical weathering, list the products resulting from the chemical weathering of igneous rocks, and list and discuss the factors that influence the type and rate of rock weathering. Many photographs accompany this summary which depict weathered landscapes. Links are provided to the online Physical Geology resources at Georgia Perimeter College.

Gore, Pamela

1995-08-29

19

Subsurface Weathering of Rocks and Soils at Gusev Crater  

NASA Technical Reports Server (NTRS)

Data collected by the Mars Exploration Rover (MER) Spirit at Gusev Crater suggest that enhanced weathering of rocks and soils occurs beneath the immediate surface. We suggest that this alteration occurs over geological timescales under present climatic conditions and is a result of diurnal condensation of thin-films of water on subsurface materials. Additional information is included in the original extended abstract.

Yen, A. S.; Ming, D. W.; Gellert, R.; Clark, B. C.; Morris, R. V.; Rodionov, D.; Schroeder, C.

2005-01-01

20

Weathering of Fractured Rock in the Deep Critical Zone  

NASA Astrophysics Data System (ADS)

The interfaces where intact bedrock physically and chemically weathers to form regolith, are often hidden deep within the critical zone and are thus difficult to access. However, weathering of primary minerals along bedrock fractures located in the groundwater or deep vadose zones may supply significant weathering products to streams and oceans and influence topography and soil fertility. We investigated the deep critical zone in the Bisley watershed at the Luquillo Critical Zone Observatory from two 9.6 cm diameter boreholes drilled with a hydraulic rotary drill to 37.2 and 27.0 m depth. Continuous core samples through coherent rock were taken using an HQ-wireline barrel. Bulk solid-state chemical analysis and quantitative XRD were performed on rock and saprock samples. Thin sections were examined by optical microscopy, SEM, EDS, and EPMA. A history of low- to moderate-grade metamorphism is reflected by the presence of epidote, prehnite, pyrite, and tourmaline in the fresh rock (visibly un-weathered). Fresh rock also contains abundant plagioclase and Mg-rich chlorite, with lesser quartz, K-spar, and pyroxene. The quartz is microcrystalline and present in variable quantities in the fresh rock, consistent with infiltration of Si-rich hydrothermal fluids. Evidence of reaction-induced porosity development is observed in the visibly un-weathered rock, but the majority of weathering occurs within weathering rinds (<15 mm thick). These rinds are developed on fracture surfaces (and the outer surfaces of exposed corestones) and contain abundant secondary Fe(III)-oxides, which fill pore space, decreasing porosity relative to the core-rind interface. In the case of exposed corestones, the rinds spall off, refresing the surface for continued weathering. In the case of subsurface corestones, rinds grow thicker and sometimes consume rock fragments entirely. Borehole cores revealed repeated zones of highly fractured rock, interpreted as subsurface corestones, embedded within layers of regolith. Some corestones are massive and others are highly fractured. Subsurface corestones are larger and less fractured in the borehole drilled under a ridge, compared to the borehole drilled near a stream channel. As corestone size is thought to be a function of fracture spacing, the location of the valleys and ridges in the watershed may be controlled by the fracture spacing of the underlying bedrock. Drilling terminated in coherent rock, thought to be bedrock based on a model that hypothesized a thickness for the corestone-regolith zone [1]. Both profiles indicate that weathering proceeds 10's of meters below the stream channel; thus weathering depth is not controlled by local base level. Furthermore, weathering rinds on fracture surfaces at depth indicate that water and oxygen are transported below the stream channel; thus not all of the water in the watershed is discharged to the stream. [1] Fletcher and Brantley (2010) Amer. J. Sci 310, 131-164.

Buss, H. L.; Bazilevskaya, E.; Brantley, S. L.; Scatena, F. N.; Schulz, M. S.; White, A. F.

2012-12-01

21

Association of trace elements with iron oxides during rock weathering  

SciTech Connect

The association of trace elements with Fe oxides during the early stages of rock weathering was determined by analysis of fresh diabase and granite rocks, their associated whole and size-separated saprolites, and goethite by neutron activation and X-ray fluorescence. The same elements are found to be associated with Fe oxides when the results are interpreted by analysis of correlation, by the distribution of elements in the various size fractions by the effects of removing free Fe oxides, and by direct analysis of geothite from the saprolite. The elements Co, Cr, Mn, Sc, Th, U, Zn, and the heavy rare-earth elements during the weathering of diabase, and As, Co, Cr, Sc, Th, U, Zn, and the heavy rare-earth elements during the weathering of granite are associated with Fe oxides. The concentrations of Mn are too low in this system to separate the effects of Mn oxides from those of Fe oxides.

Koons, R.D.; Helmke, P.A.; Jackson, M.L.

1980-01-01

22

Rock Rinds at Meridiani and Surface Weathering Phenomena  

NASA Astrophysics Data System (ADS)

The Rock Abrasion Tool (RAT) on the Mars rover Opportunity can brush away surface dust and grind away outcrop surface, exposing presumably less altered rock at depths of several mm. Alpha particle X-ray spectrometer (APXS) and Moessbauer spectrometer (MB) analyses of pre- and post-RAT targets, thus, provide information on the chemical nature of weathering of Meridiani outcrop rocks. To date, Opportunity has analyzed some 25 undisturbed rock surfaces, brushed and then analyzed 7 more, and ground 23 targets for IDD analysis. Panoramic camera images show that outcrop surfaces are typically either buff or purple (as viewed in bands centered at 673, 535, and 432 nm, Farrand et al., JGR, in press). Relatively flat surfaces that are approximately parallel to the ground are typically buff, whereas those that slope steeply tend to be purple. Surfaces of rock interiors ground by the RAT are also commonly purple. Spectrally, these color differences correspond to more oxidized (buff) and less oxidized (purple), and appear to relate to the degree of eolian abrasion. Flat-lying surfaces are not eroded as quickly, thus surfaces chemically weathered by exposure to tenuous atmospheric vapor may be preserved. These observations are consistent with in-situ analyses of rock surfaces and interiors. Compared to interiors, rock surfaces have about 1/3 less S, and in general, surface compositions lie between those of rock interiors and average surface soil. In detail, they differ from soil-rock mixtures as follows: surfaces are relatively depleted in Mg, Fe, Mn, Ti, and Cr, and they are enriched in Al, Na, K, P, Cl, and Si. From MB analyses, surfaces are richer (compared to soil-rock mixtures) in oxidized Fe phases and poorer in magnetite, olivine, and pyroxene. Morphologically, numerous flat-lying rocks and outcrop surfaces that are at or near the ground surface have a rind of erosionally resistant material. Such rinds are also chemically distinct from outcrop interiors. A rind/subjacent rock pair analyzed in detail was "Lemon Rind" and "Strawberry," ca. sols 555-560. The rind is depleted in S (balanced mainly by increased Si and Al) and, compared to a soil-rock mixture, it is depleted in Mg, Ti, Cr, Mn, and slightly in Fe, and it is enriched in Na, Cl, K, and P. Differences between rock surfaces and interiors, and between hardened weathering rinds and rock interiors, are consistent with loss of Mg-sulfate, oxidation of mafic minerals, enrichment of siliciclastic material, e.g., feldspar, and enrichment in chloride. These changes are consistent with slow rates of chemical weathering via interaction with small amounts of atmospheric water vapor or condensation. Erosionally resistant rinds may be related to preservation of aqueous condensate by a thin cover of soil on flat, near-surface rocks.

Jolliff, B.; Knoll, A.; Farrand, W.; Sullivan, R.

2006-12-01

23

Cracks in desert pavement rocks: Further insights into mechanical weathering by directional insolation  

E-print Network

Cracks in desert pavement rocks: Further insights into mechanical weathering by directional August 2010 Keywords: Desert pavements Physical weathering Desert geomorphology Insolation weathering Fractures The formation of cracks is a fundamental first step in the physical weathering of rocks in desert

Ahmad, Sajjad

24

Space Weathering of Lunar Rocks and Regolith Grains  

NASA Technical Reports Server (NTRS)

The exposed surfaces of lunar soil grains and lunar rocks become modified and coated over time with a thin rind of material (patina) through complex interactions with the space environment. These interactions encompass many processes including micrometeorite impacts, vapor and melt deposition, and solar wind implantation/sputtering effects that collectively are referred to as "space weathering". Studies of space weathering effects in lunar soils and rocks provide important clues to understanding the origin and evolution of the lunar regolith as well as aiding in the interpretation of global chemical and mineralogical datasets obtained by remote-sensing missions. The interpretation of reflectance spectra obtained by these missions is complicated because the patina coatings obscure the underlying rock mineralogy and compositions. Much of our understanding of these processes and products comes from decades of work on remote-sensing observations of the Moon, the analysis of lunar samples, and laboratory experiments. Space weathering effects collectively result in a reddened continuum slope, lowered albedo, and attenuated absorption features in reflectance spectra of lunar soils as compared to finely comminuted rocks from the same Apollo sites. Space weathering effects are largely surface-correlated, concentrated in the fine size fractions, and occur as amorphous rims on individual soil grains. Rims on lunar soil grains are highly complex and span the range between erosional surfaces modified by solar wind irradiation to depositional surfaces modified by the condensation of sputtered ions and impact-generated vapors. The optical effects of space weathering effects are directly linked to the production of nanophase Fe metal in lunar materials]. The size of distribution of nanophase inclusions in the rims directly affect optical properties given that large Fe(sup o) grains (approx 10 nm and larger) darken the sample (lower albedo) while the tiny Fe(sup o) grains (<5nm) are the primary agent in spectral "reddening". More recent work has focused on the nature and abundance of OH/H2O in the lunar regolith using orbital data and samples analyses. Advances in sample preparation techniques have made possible detailed analyses of patina-coated rock surfaces. Major advances are occurring in quantifying the rates and efficiency of space weathering processes through laboratory experimentation.

Keller, L. P.

2013-01-01

25

Weathered stony meteorites from Victoria Land, Antarctica, as possible guides to rock weathering on Mars  

NASA Technical Reports Server (NTRS)

Parallel studies of Martian geomorphic features and their analogs on Earth continue to be fruitful in deciphering the geologic history of Mars. In the context of rock weathering, the Earth-analog approach is admirably served by the study of meteorites recovered from ice sheets in Antarctica. The weathering environment of Victoria Land possesses several Mars-like attributes. Four of the five Antarctic meteorites being studied contain rust and EETA79005 further possesses a conspicuous, dark, weathering rind on one side. Secondary minerals (rust and salts) occur both on the surfaces and interiors of some of the samples and textural evidence indicates that such secondary mineralization contributed to physical weathering (by salt riving) of the rocks. Several different rust morphologies occur and emphasis is being placed on identifying the phase compositions of the various rust occurrances. A thorough understanding of terrestrial weathering features of the meteorites is a prerequisite for identifying possible Martian weathering features (if such features exist) that might be postulated to occur in some meteorites.

Gooding, J. L.

1984-01-01

26

The durability of rocks--Developing a test of rock resistance to chemical weathering  

Microsoft Academic Search

Dissolution rates of 39 rock-forming minerals were determined at 20 °C and 100 °C and different pH values, using experimental set-ups which achieve near-zero cation concentrations. Weathering rates in nature for rock above surface were estimated from data in this study and data in the literature. Extraction in a Soxhlet extractor with boiling 2.5 m acetic acid causes an acceleration

WALTER A. FRANKE

2009-01-01

27

Inscription legibility method for estimating rock weathering rates  

NASA Astrophysics Data System (ADS)

Relative legibility of dated inscription is closely associated with measured surface recessions for 3895 Vermont marble tombstones, and the resulting ordinal-to-ratio transfer function allows weathering rates to be computed for many exposed rock surfaces that cannot be measured by more accurate methods. Case studies demonstrate applications of the technique. (1) Surfaces of horizontal ground-level marble plaques have dissolved at steady rates of 1.3 mm/100 yr in Providence, RI and 1.1 mm/100 yr in Richmond, VA despite reports of increasing acid rain. (2) Vertical faces of century-old marble tombstones in upper midwestern United States small-towns have receded 10 times faster (1.4 mm/ 100 yr) than have stones in less polluted environments. (3) Vertical faces of limestone monuments have receded at half the rate (0.5 mm/ 100 yr) of Vermont marble tombstones (0.9 mm/ 100 yr) in Louisville, KY. (4) Aspect differences have not affected recession rates of marble pillar surfaces near Philadelphia, PA. (5) Aspect is important to sandstone granular weathering rates at Inscription Rock, NM, where north-facing cliffs recede 3 times faster (0.9 mm/ 100 yr) than do southeast-facing cliffs. (6) Horizontal pre-weathered quartizite surfaces at a scenic overlook in Maryland recede at 0.6 mm/ 100 yr.

Meierding, Thomas C.

1993-03-01

28

Investigating sedimentary rock deposition and weathering in Mawikwe Bay Sea Caves  

NSDL National Science Digital Library

A field investigation to the Mawikwe Bay Sea Caves of northern Wisconsin along Lake Superior in the winter. Students will investigate deposition of sedimentary rocks and weathering of the rocks to produce sea caves.

29

Antarctic glaciers and rock weathering: Exploring chemical and mineralogy processes within the blue ice fields  

E-print Network

Antarctic glaciers and rock weathering: Exploring chemical and mineralogy processes within the blue, and precipitation of weathering products (e.g. magnesium carbonates and iron oxyhydroxides, or `rust'), is highly into a virtue by using weathering products to unlock the information that contain regarding the mechanisms

Guo, Zaoyang

30

Chemical weathering of granitic rock: experiments and Pb-Li isotopes tracing Romain Millot  

E-print Network

Chemical weathering of granitic rock: experiments and Pb-Li isotopes tracing Romain Millot Philippe shown that most of the lead in the groundwaters is of geogenic origin. Combining a weathering model and field observations, we were able to define a two-step weathering process that includes a control

Paris-Sud XI, Université de

31

Field Guide to Rock Weathering. Earth Science Curriculum Project Pamphlet Series PS-1.  

ERIC Educational Resources Information Center

Highlighted are the effects of weathering through field investigations of the environment, both natural rocks, and the urban environment's pavements, buildings, and cemeteries. Both physical weathering and chemical weathering are discussed. Questions are presented for post-field trip discussion. References and a glossary are provided. (Author/RE)

Boyer, Robert E.

32

Development of unusual rock weathering features in the Cordillera Blanca, Peru  

NASA Astrophysics Data System (ADS)

Mylonite textures in granodiorite boulders are responsible for higher rates of surface denudation of host rocks and the progressive development of unusual rock weathering features, termed weathering posts. These textures are characterized by smaller grain sizes, higher biotite content, and a higher biotite axial ratio in host rocks relative to weathering posts. Elemental concentrations do not show a significant difference between weathering posts and the host rocks in which they are found, and this reflects the absence of a weathering residue on the rock surfaces. Chemical weathering loosens the bonds between mineral grains through the expansion of biotite, and the loosened grains fall off or are blown off the boulder surface and continue their chemical alteration in the surrounding soil. The height of weathering posts on late Quaternary moraines increases at a linear rate of ~ 1.45 ± 0.45 cm (1000 yr)- 1 until post heights reach the diameter of host rocks. Such a rate of boulder denudation, if unrecognized, would generate significant errors (> 20%) in cosmogenic exposure ages for Pleistocene moraines. Given the paucity of boulders with diameters that significantly exceed 1.5 m, the maximum age of utility of weathering posts as a numeric age indicator is ~ 100 ka.

Rodbell, Donald T.; Frey, Holli M.; Manon, Matthew R. F.; Smith, Jacqueline A.; McTurk, Nicholas A.

2012-01-01

33

The Hole as a Whole: Geological and Microbiological Features of Rock Weathering in Arid and Hyper-Arid Environments  

E-print Network

The Hole as a Whole: Geological and Microbiological Features of Rock Weathering in Arid and Hyper, Kibbutz Qetura, Hevel Eilot 88840, Israel A variety of rock weathering patterns and morphologies were and honeycomb weathering). Many studies attempted to explain the weathering morphology and mechanism. Yet

Simon, Emmanuel

34

Fractionation of Cu, Fe, and Zn isotopes during the oxidative weathering of sulfide-rich rocks  

Microsoft Academic Search

We measured the Fe, Cu, and Zn isotopic compositions of the fluids generated during leaching experiments with pyrite-, chalcopyrite-, and sphalerite-rich rocks and with a sphalerite mineral separate. Our study demonstrates that the oxidative weathering of sulfide-rich rocks can produce substantial variations in Fe (?1.75 to +1.0‰ ?56Fesolution-pyrite rock) and Cu (0.0 to +2.0‰ ?65Cusolution-chalcopyrite rock) isotopes and small variations

Alvaro Fernandez; David M. Borrok

2009-01-01

35

Uranium–thorium chronometry of weathering rinds: Rock alteration rate and paleo-isotopic record of weathering fluids  

Microsoft Academic Search

The potential of 238U–234U–230Th chronometry for constraining the formation rate of weathering rinds developed on fresh rocks is assessed by analyzing a weathering rind on a basaltic clast from a 125 kyr old Costa Rican alluvial terrace. Eighteen subsamples were collected from one section of the clast by drilling cores (4 mm in diameter and 5 mm depth) along two transects straddling the

E. Pelt; F. Chabaux; C. Innocent; A. K. Navarre-Sitchler; P. B. Sak; S. L. Brantley

2008-01-01

36

Release of uranium and thorium from granitic rocks during in situ weathering and initial erosion  

E-print Network

been leached from the Granite Mountains of Wyoming from Eocene to the present. The depth of weather- ing is about 10 meters. ROSHOLT, et al. (1971), in a comparison of plutonic granitic rocks and glassy volcanic rocks, found that leaching of U... been leached from the Granite Mountains of Wyoming from Eocene to the present. The depth of weather- ing is about 10 meters. ROSHOLT, et al. (1971), in a comparison of plutonic granitic rocks and glassy volcanic rocks, found that leaching of U...

Ledger, Ernest Broughton

2012-06-07

37

An Examination of the Space Weathering Patina of Lunar Rock 76015  

NASA Technical Reports Server (NTRS)

Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. Rocks have much longer surface lifetimes than an individual soil grain and thus record a longer history of exposure. By studying the weathering products which have built up on a rock surface, we can gain a deeper perspective on the weathering process and better assess the relative importance of various weathering components. The weathered coating, or patina, of the lunar rock 76015 has been previously studied under SEM and also by TEM using ultramicrotome sample preparation methods. However, to really understand the products involved in creating these coatings, it is helpful to examine the patina in cross section, something which is now possible though the use of Focused Ion Beam (FIB) sample prep techniques, which allows us to preserve intact the delicate stratigraphy of the patina coating and provides a unique cross-sectional view of the space weathering process. Several samples have been prepared from the rock and the coatings are found to be quite variable in thickness and composition from one sample to the next.

Noble, S.; Chrisoffersen, R.; Rahman, Z.

2011-01-01

38

The effect of rock composition on cyanobacterial weathering of crystalline basalt and rhyolite.  

PubMed

The weathering of volcanic rocks contributes significantly to the global silicate weathering budget, effecting carbon dioxide drawdown and long-term climate control. The rate of chemical weathering is influenced by the composition of the rock. Rock-dwelling micro-organisms are known to play a role in changing the rate of weathering reactions; however, the influence of rock composition on bio-weathering is unknown. Cyanobacteria are known to be a ubiquitous surface taxon in volcanic rocks. In this study, we used a selection of fast and slow growing cyanobacterial species to compare microbial-mediated weathering of bulk crystalline rocks of basaltic and rhyolitic composition, under batch conditions. Cyanobacterial growth caused an increase in the pH of the medium and an acceleration of rock dissolution compared to the abiotic controls. For example, Anabaena cylindrica increased the linear release rate (R(i)(l)) of Ca, Mg, Si and K from the basalt by more than fivefold (5.21-12.48) and increased the pH of the medium by 1.9 units. Although A. cylindrica enhanced rhyolite weathering, the increase in R(i)(l) was less than threefold (2.04-2.97) and the pH increase was only 0.83 units. The R(i)(l) values obtained with A. cylindrica were at least ninefold greater with the basalt than the rhyolite, whereas in the abiotic controls, the difference was less than fivefold. Factors accounting for the slower rate of rhyolite weathering and lower biomass achieved are likely to include the higher content of quartz, which has a low rate of weathering and lower concentrations of bio-essential elements, such as, Ca, Fe and Mg, which are known to be important in controlling cyanobacterial growth. We show that at conditions where weathering is favoured, biota can enhance the difference between low and high Si-rock weathering. Our data show that cyanobacteria can play a significant role in enhancing rock weathering and likely have done since they evolved on the early Earth. PMID:22694082

Olsson-Francis, K; Simpson, A E; Wolff-Boenisch, D; Cockell, C S

2012-09-01

39

Probing the Depths of Space Weathering: A Cross-sectional View of Lunar Rock 76015  

NASA Technical Reports Server (NTRS)

The term "space weathering" refers to the cumulative effects of several processes operating at the surface of any solar system body not protected by a thick atmosphere. These processes include cosmic and solar ray irradiation, solar wind implantation and sputtering, as well as melting and vaporization due to micrometeorite bombardment. Space weathering discussions have generally centered around soils but exposed rocks will also incur the effects of weathering. Rocks have much longer surface lifetimes than an individual soil grain and thus record a longer history of exposure. By studying the weathering products which have built up on a rock surface, we can gain a deeper perspective on the weathering process and better assess the relative importance of various weathering components. The weathered coating, or patina, of the lunar rock 76015 has been previously studied using SEM and TEM. It is a noritic breccia with both "glazed" (smooth glassy) and "classic" (microcratered and pancake-bearing) patina coatings. Previous TEM work on 76015 relied on ultramicrotomy to prepare cross sections of the patina coating, but these sections were limited by the "chatter" and loss of material in these brittle samples. Here we have used a focused ion beam (FIB) instrument to prepare cross sections in which the delicate stratigraphy of the patina coating is beautifully preserved.

Noble, Sarah K.; Keller, L. P.; Stroud, Rhonda

2007-01-01

40

Soft computing modeling for indirect determination of the weathering degrees of a granitic rock  

NASA Astrophysics Data System (ADS)

Determination of weathering degrees of intact rock has been one of the difficult problems in engineering geology. Additionally, granitic rocks are commonly used as building and ornamental stones and pavement material in various civil engineering structures. For this reason, correct determination of weathering degree of the granitic rocks has a crucial importance in engineering geology. Up to now, some approaches for the determination of weathering degree of granitic rocks have been proposed. Some soft computing methods have been used for the determination of the weathering degree of the granitic rocks. However, in literature, the adaptive neuro-fuzzy inference system has not been used for the weathering classification yet. For this reason, the main purpose of the present study is to apply some soft computing methods such as artificial neural networks and adaptive neuro-fuzzy inference system on the determination of weathering degree of a granitic rock selected from Turkey by using some index and mechanical properties. The study is formed by four main stages such as sampling, testing, modeling and assessment of the model performances. During the modeling stage, two weathering prediction models with multi-inputs are developed with two soft computing techniques such as artificial neural networks and the adaptive neuro-fuzzy inference system. The general performances of models developed in this study are close; however the adaptive neuro-fuzzy inference system exhibits the best performance considering the performance index and the degree of consistency. Finally, both models developed in this present study can be used when determining the weathering degree. The results obtained from this study revealed that the soft computing techniques used in the study are highly useful tools to solve some complex problems encountered frequently in engineering geology.

Dagdelenler, G.; Sezer, E.; Gokceoglu, C.

2010-05-01

41

Porosity and surface area evolution during weathering of two igneous rocks  

NASA Astrophysics Data System (ADS)

During weathering, rocks release nutrients and store water vital for growth of microbial and plant life. Thus, the growth of porosity as weathering advances into bedrock is a life-sustaining process for terrestrial ecosystems. Here, we use small-angle and ultra small-angle neutron scattering to show how porosity develops during initial weathering under tropical conditions of two igneous rock compositions, basaltic andesite and quartz diorite. The quartz diorite weathers spheroidally while the basaltic andesite does not. The weathering advance rates of the two systems also differ, perhaps due to this difference in mechanism, from 0.24 to 100 mm kyr-1, respectively. The scattering data document how surfaces inside the feldspar-dominated rocks change as weathering advances into the protolith. In the unaltered rocks, neutrons scatter from two types of features whose dimensions vary from 6 nm to 40 ?m: pores and bumps on pore-grain surfaces. These features result in scattering data for both unaltered rocks that document multi-fractal behavior: scattering is best described by a mass fractal dimension (Dm) and a surface fractal dimension (Ds) for features of length scales greater than and less than ˜1 ?m, respectively. In the basaltic andesite, Dm is approximately 2.9 and Ds is approximately 2.7. The mechanism of solute transport during weathering of this rock is diffusion. Porosity and surface area increase from ˜1.5% to 8.5% and 3 to 23 m2 g-1 respectively in a relatively consistent trend across the mm-thick plagioclase reaction front. Across this front, both fractal dimensions decrease, consistent with development of a more monodisperse pore network with smoother pore surfaces. Both changes are consistent largely with increasing connectivity of pores without significant surface roughening, as expected for transport-limited weathering. In contrast, porosity and surface area increase from 1.3% to 9.5% and 1.5 to 13 m2 g-1 respectively across a many cm-thick reaction front in the spheroidally weathering quartz diorite. In that rock, Dm is approximately 2.8 and Ds is approximately 2.5 prior to weathering. These two fractals transform during weathering to multiple surface fractals as micro-cracking reduces the size of diffusion-limited subzones of the matrix. Across the reaction front of plagioclase in the quartz diorite, the specific surface area and porosity change very little until the point where the rock disaggregates into saprolite. The different patterns in porosity development of the two rocks are attributed to advective infiltration plus diffusion in the rock that spheroidally fractures versus diffusion-only in the rock that does not. Fracturing apparently diminishes the size of the diffusion-limited parts of the spheroidally weathering rock system to promote infiltration of meteoric fluids, therefore explaining the faster weathering advance rate into that rock.

Navarre-Sitchler, Alexis K.; Cole, David R.; Rother, Gernot; Jin, Lixin; Buss, Heather L.; Brantley, Susan L.

2013-05-01

42

Porosity and surface area evolution during weathering of two igneous rocks  

SciTech Connect

During weathering, rocks release nutrients and storewater vital for growth ofmicrobial and plant life. Thus, the growth of porosity as weathering advances into bedrock is a life-sustaining process for terrestrial ecosystems. Here, we use small-angle and ultra small-angle neutron scattering to show how porosity develops during initial weathering under tropical conditions of two igneous rock compositions, basaltic andesite and quartz diorite. The quartz diorite weathers spheroidally while the basaltic andesite does not. The weathering advance rates of the two systems also differ, perhaps due to this difference in mechanism, from 0.24 to 100 mm kyr1, respectively. The scattering data document how surfaces inside the feldspar-dominated rocks change as weathering advances into the protolith. In the unaltered rocks, neutrons scatter fromtwo types of featureswhose dimensions vary from6 nmto 40 lm: pores and bumps on pore grain surfaces. These features result in scattering data for both unaltered rocks that document multi-fractal behavior: scattering is best described by amass fractal dimension (Dm) and a surface fractal dimension (Ds) for features of length scales greater than and less than 1 lm, respectively. In the basaltic andesite, Dm is approximately 2.9 and Ds is approximately 2.7. The mechanism of solute transport during weathering of this rock is diffusion. Porosity and surface area increase from 1.5%to 8.5%and 3 to 23 m2 g1 respectively in a relatively consistent trend across themm-thick plagioclase reaction front. Across this front, both fractal dimensions decrease, consistentwith development of amoremonodisperse pore networkwith smoother pore surfaces. Both changes are consistent largely with increasing connectivity of pores without significant surface roughening, as expected for transport-limited weathering. In contrast, porosity and surface area increase from 1.3% to 9.5% and 1.5 to 13 m2 g1 respectively across a many cm-thick reaction front in the spheroidally weathering quartz diorite. In that rock, Dm is approximately 2.8 andDs is approximately 2.5 prior to weathering. These two fractals transform during weathering to multiple surface fractals as micro-cracking reduces the size of diffusion-limited subzones of thematrix.Across the reaction front of plagioclase in the quartz diorite, the specific surface area and porosity change very little until the pointwhere the rock disaggregates into saprolite. The different patterns in porosity development of the two rocks are attributed to advective infiltration plus diffusion in the rock that spheroidally fractures versus diffusion-only in the rock that does not. Fracturing apparently diminishes the size of the diffusion-limited parts of the spheroidally weathering rock system to promote infiltration of meteoric fluids, thereforeexplaining the faster weathering advance rate into that rock.

Navarre-Sitchler, Alexis [Colorado School of Mines, Golden; Cole, David [Ohio State University; Rother, Gernot [ORNL; Jin, Lixin [University of Texas, El Paso; Buss, Heather [University of Bristol, UK; Brantley, S. L. [Pennsylvania State University, University Park, PA

2013-01-01

43

Identification of rock weathering and environmental control in arid catchments (northern Xinjiang) of Central Asia  

NASA Astrophysics Data System (ADS)

Chemical weathering is an integral part of the earth surface processes, whose spatial patterns and controlling factors on continental scale are still not fully understood. Highlands of the Asian continent have been shown having some of the highest observed rates of chemical weathering yet reported. However, the paucity of river gauge data in many of these terrains has limited determination of chemical weathering budget in a continental scale. A dataset of three large watersheds throughout northern Xinjiang in Central Asia is used to empirically identify chemical weathering regimes and interpret the underlying controlling factors. Detailed analysis of major ion ratios and a forward model of mass budget procedure are presented to distinguish the relative significances and contributions of silicate, carbonate weathering and evaporite dissolution. The analytical results show that carbonic acid is the most important weathering agent to the studied watersheds. Silicate weathering contributes, on average, ˜17.8% (molar basis) of total cations on a basin wide scale with an order of Zhungarer > Erlqis > Yili, indicating that silicate weathering, however, does not seem to be intense in the study basins. Evaporite dissolution, carbonate weathering and precipitation input contribute 43.6%, 29.7% and 8.9% of the total dissolved cations on average for the whole catchment, respectively. The three main morphological and hydrological units are reflected in water chemistry. Rivers from the montane areas (recharge area) of the three watersheds are very dilute, dominated by carbonate and silicate weathering, whereas the rivers of piedmont areas as well as the rivers of the sedimentary platform (runoff area) are dominated by carbonate weathering, and rivers of desert plain in the central Zhungarer basin (discharge area) are dominated by evaporite dissolution and are SO4 rich. This spatial pattern indicates that, beside lithology, runoff conditions have significant role on the regional chemical weathering regimes. Chemical weathering processes in the areas appear to be significantly climate controlled, displaying a tight correlation with runoff and aridity. Carbonate weathering are mostly influenced by runoff, which is higher in the mountainous part of the studied basins. The identification of chemical weathering regimes from our study confirmed the weathering potential and complexity of temperate watersheds in arid environment and that additional studies of these terrains are warranted. However, because the dominant weathering reactions in the sedimentary platform of northern Xinjiang are of carbonates and evaporites rather than silicate minerals, and the climatic factors have important role on the rock weathering regimes, we think that weathering at the arid temperate drainage system (Central Asia) is maybe not an important long-term sink for atmospheric CO2, if the future climate has no great change.

Zhu, Bingqi; Yu, Jingjie; Qin, Xiaoguang; Rioual, Patrick; Zhang, Yichi; Liu, Ziting; Mu, Yan; Li, Hongwei; Ren, Xiaozong; Xiong, Heigang

2013-04-01

44

Confined groundwater zone and slope instability in weathered igneous rocks in Hong Kong  

E-print Network

. Generally studies of groundwater for determining slope stability treat the saprolite above the rockhead (HKZ) may exist at depth, either in the lower saprolite or at the rockhead. The completely decomposed; Confined aquifer; Hydraulic conductivity; Factor of safety; Weathered igneous rocks; Saprolite; Kaolin

Jiao, Jiu Jimmy

45

Rocks  

NSDL National Science Digital Library

This guide explores rocks, from processes that can change them (such as weathering), to what can happen to them as they move through the rock cycle. Using this guide, teachers of middle school students will focus on the tangible process of sedimentary roc

National Science Teachers Association (NSTA)

2009-07-01

46

Acid rock drainage and rock weathering in Antarctica: important sources for iron cycling in the Southern Ocean.  

PubMed

Here we describe biogeochemical processes that lead to the generation of acid rock drainage (ARD) and rock weathering on the Antarctic landmass and describe why they are important sources of iron into the Antarctic Ocean. During three expeditions, 2009-2011, we examined three sites on the South Shetland Islands in Antarctica. Two of them displayed intensive sulfide mineralization and generated acidic (pH 3.2-4.5), iron-rich drainage waters (up to 1.78 mM Fe), which infiltrated as groundwater (as Fe(2+)) and as superficial runoff (as Fe(3+)) into the sea, the latter with the formation of schwertmannite in the sea-ice. The formation of ARD in the Antarctic was catalyzed by acid mine drainage microorganisms found in cold climates, including Acidithiobacillus ferrivorans and Thiobacillus plumbophilus. The dissolved iron (DFe) flux from rock weathering (nonmineralized control site) was calculated to be 0.45 × 10(9) g DFe yr(-1) for the nowadays 5468 km of ice-free Antarctic rock coastline which is of the same order of magnitude as glacial or aeolian input to the Southern Ocean. Additionally, the two ARD sites alone liberate 0.026 and 0.057 × 10(9) g DFe yr(-1) as point sources to the sea. The increased iron input correlates with increased phytoplankton production close to the source. This might even be enhanced in the future by a global warming scenario, and could be a process counterbalancing global warming. PMID:23682976

Dold, B; Gonzalez-Toril, E; Aguilera, A; Lopez-Pamo, E; Cisternas, M E; Bucchi, F; Amils, R

2013-06-18

47

Effect of groundwater and sea weathering cycles on the strength of chalk rock from unstable coastal cliffs of NW France.  

E-print Network

ranging between 10% and 17%. When chalk samples are submitted to an artificial weathering cycle to an artificial weathering with sea water, the decrease of UCS strength and Young's modulus achieves a maximum1 Effect of groundwater and sea weathering cycles on the strength of chalk rock from unstable

Boyer, Edmond

48

Climatic controls on mechanical rock strength and channel incision due to bedrock weathering, Kohala Peninsula, Hawaii  

NASA Astrophysics Data System (ADS)

Orographic precipitation gradients are prevalent in mountainous terrains, and climate-dependent bedrock weathering may play an important role in the incision of bedrock channels and the evolution of landscapes. Kohala Peninsula on the big island of Hawaii presents a unique natural setting for exploring climate sensitivity of landscape erosion, with over an order of magnitude variation in mean annual precipitation, a landscape composed entirely of weatherable basalt, and systematic variations in fluvial incision and resulting topography across the climate gradient. We hypothesize that increases in local mean annual precipitation will promote long-term channel incision rates due to increases in bedrock weathering, but measurements of rock strength within bedrock channels will be greatly influenced by the efficient removal of weathered rock by fluvial erosion. Mechanical properties of bedrock were measured at a total of 13 sites across two watersheds that vary in local mean annual precipitation from 0.27 - 2.25 m/yr. In situ strength measurements were collected using a Schmidt hammer with a pseudo-random sampling method along transects parallel to stream direction and just above the channel thalweg. Tensile strength and elastic moduli were also measured in the laboratory on cores collected from a subset of the same transects. Long-term channel incision rates were independently constrained from the local valley relief and the ages of mapped basalt units that form the relatively unmodified volcanic shield of Kohala. When strength data comes from sites of low long-term incision, we find strong power-law relationships between both rock strength measurements and local mean annual precipitation. However, for sites with high precipitation rate and variable erosion rates, we find significant variability in the rock strength. We interpret this to reflect the removal of weathered rock by erosion. In order to interpret the influence of climate in our dataset, we made a normalized "climate-incision index" by dividing local precipitation rate (m/yr) by the local erosion rate (m/yr). When rock strength is plotted against this climate-incision index the data nicely collapses into consistent power-law relationships. Therefore, by removing the influence of local long-term incision from the data, the relationship between decreasing rock strength and increasing local mean annual precipitation becomes clear. Identifying this relationship may help explain the varied patterns of incision observed across the Kohala peninsula. Finally, if changes in mechanical rock strength are representative of weathering patterns across the landscape, this result may also suggest an influence on other key fluvial characteristics, such as sediment supply in channels. While Kohala may be an ideal site to isolate these trends, influences of bedrock weathering may be important for landscape evolution across many other orographic precipitation gradients.

Murphy, B. P.; Johnson, J. P.; Gasparini, N. M.; Sklar, L. S.

2013-12-01

49

Weather  

NSDL National Science Digital Library

This is a first grade weather unit. SEASONS Fall Winter Build a Snowman Spring Summer What things determine and effect the weather? Cloud Precipitation Sunshine Temperature Visibility Wind Direction Wind Force WEATHER VIDEOS Tornado Hurricane Hail Lightning FUN AND GAMES Dress the Bear for the Weather The Great Weather Race Game Weather coloring books for kids ...

Stearns, Ms.

2008-10-25

50

Weather  

NSDL National Science Digital Library

This lesson is written for fourth grade students. Students will explore weather and the effects it has on their lives. What is weather? video of what is weather Let's take a walk through the weather. Put on your hats and coats! Clouds Cloud Types Clouds - Dan's Wild Weather Page What to Wear? What to Wear? What to Drink? Weather Patterns and Climatic Regions ...

Bullough, Ms.

2010-06-24

51

A landscape in three biospheres: biological rock weathering in a model ecosystem  

NASA Astrophysics Data System (ADS)

Biological rock weathering is the process by which life breaks down minerals into forms that are readily available for creation of an ecosystem. In order to test how microbes, plants and mycorrhizal communities interact with bedrock to initiate a primary ecosystem that will eventually lead to soil formation, we developed a modular experiment in the desert biome of Biosphere-2. In this presentation we present selected phases in the development of the experimental setup. Briefly, we aimed to replicate a large-scale primordial landscape in a closed, mesocosm system involving six carefully designed, identical chambers, each containing 48 experimental columns, 30cm long. The rocks used, i.e. basalt, rhyolite, granite and schist, represent four prevalent rock types in the natural landscape. The biotic communities are represented by combinations of rock microbial communities, plants and their associated mycorrhizae. Bacterial inoculum was optimized for each rock type. Each model was created to remain completely separated from outside influence. We expect that this experiment will provide crucial knowledge about primary interactions between rock and biota on Earth. Experimental Modules

Presler, J. K.

2012-12-01

52

The Influences Of Grain Sizes And Chemical Weathering Level On Extractability Of Elements From Sedimentary Rock  

NASA Astrophysics Data System (ADS)

The extractability of elements (Cu, Rb, Sr, La and Pb) from sedimentary rock (black slate) was investigated for establishing reliable extraction method. At first, the influence of the grain sizes on the extractability was examined by using non-weathered sample. Cu, Sr, La and Pb were abundantly extracted from roughly crushed black slate, whereas Rb extraction from powdered one was more effective. Especially, the dissolutions of heavy metals from well-ground slate were drastically lowered maybe due to re-adsorption artifacts. The extraction experiments using the black slate with different weathering levels were also performed for the purpose of investigations of chemical weathering on the dissolution behavior of above elements. The extracted solutions were successively filtered through 0.45 ?m, 0.20 ?m and 100 kDa. The almost of all elements were extracted from non-weathered as truly dissolved species. On the other hand, the elements extracted from weathered slates were almost completely removed by the ultrafiltration except some of alkali and alkali earth elements, indicating no existence of truly dissolved species. They were adsorbates on Al and Fe-bearing colloidal particles or their components.

Ogawa, Y.; Yamasaki, S.; Tsuchiya, N.

2008-02-01

53

Terrestrial laser scanning and exploratory spatial data analysis for the mapping of weathering forms on rock art panels  

Microsoft Academic Search

Rock art conservators are faced with complex decisions to prioritize rock art panels for protection from destructive forces of weathering. We provide a system to facilitate such decision making that blends traditional remote sensing with interactive techniques of exploratory spatial data analysis. Our system, ‘mapping weathering forms in three-dimensional (3D)’ (MapWeF) uses a 3D laser scanning device for sub-centimetre data

B. J. Vogt; R. M. Edsall

2010-01-01

54

Weather  

NSDL National Science Digital Library

Have you ever wondered how the weather man, or meteorolgist, on TV knows what to say about tomorrow\\'s weather? It\\'s because they have certain tools that they use that help them predict what the weather will be. Throughout this school year you are going to be making tools and predicting weather just like a meterorologist! Task You are going to be weather forcasters! You are going to record and track weather patterns throughout the year. You will also use weather tools to make predictions about the weather like real weather forecasters! The Process 1. First we need to learn a little bit about weather so ...

Williams, Ms.

2005-10-25

55

Rock-moisture dynamics in a hillsope underlain with weathered and fractured argillite  

NASA Astrophysics Data System (ADS)

In order to explore the recharge process through a deep, weathered bedrock zone in a strongly seasonal rainfall environment, we document the early rainy season and annual rock-moisture dynamics along a steep Northern California hillslope underlain by a thick zone of unsaturated weathered and fractured argillite. All runoff to the channel at the base of the hillslope occurs via groundwater flow that is perched on underlying low-permeability fresh bedrock. We report the timing and depth of the first rise in moisture content in response to early winter rains and storm, seasonal, and annual moisture dynamics throughout the zone. Our measurements show that after a long summer dry season, the first rains rapidly penetrate through the soil mantle and into the underlying weathered bedrock. Large rains generate a response as deep as 6 m into the weathered bedrock within a few weeks. But within hours to days of the start of rain, the perched groundwater, at depths from 4 to 18 m below the surface, responds. The wetting advanced into the bedrock, with the groundwater response magnitude and timing differing greatly across the hillslope. We distinguish soil moisture from rock moisture (which includes both exchangeable matrix water and fracture water) and find that while the soil moisture dynamically rises and falls with each successive storm event, the rock moisture in the shallow, weathered bedrock tends to vary less after initial wet up. Surprisingly, despite the more than 1400 mm of annual water flux through the unsaturated zone, the lower portions near the water table show no moisture variation, even as the water table rises and falls with each storm pulse. These observations suggest that fracture flow plays a predominant role in transmitting water to the water table, and hence, the runoff characteristics, water chemistry, rock-moisture availability to vegetation, the hillslope stability itself is tied to this process. We present a conceptual model to explain these dynamics, suggesting that the rapid-delivery mechanism of unsaturated flow, and thus recharge, to the water table is through a vertically varying fracture network bounded by low-conductivity matrix bedrock. The near-surface saprolite may play an important role in creating elevated moisture conditions sufficient to cause rapid drainage to the fracture system with incoming rains.

Salve, R.; Rempe, D. M.; Dietrich, W.

2012-12-01

56

Life on rock. Scaling down biological weathering in a new experimental design at Biosphere-2  

NASA Astrophysics Data System (ADS)

Biological colonization and weathering of bedrock on Earth is a major driver of landscape and ecosystem development, its effects reaching out into other major systems such climate and geochemical cycles of elements. In order to understand how microbe-plant-mycorrhizae communities interact with bedrock in the first phases of mineral weathering we developed a novel experimental design in the Desert Biome at Biosphere-2, University of Arizona (U.S.A). This presentation will focus on the development of the experimental setup. Briefly, six enclosed modules were designed to hold 288 experimental columns that will accommodate 4 rock types and 6 biological treatments. Each module is developed on 3 levels. A lower volume, able to withstand the weight of both, rock material and the rest of the structure, accommodates the sampling elements. A middle volume, houses the experimental columns in a dark chamber. A clear, upper section forms the habitat exposed to sunlight. This volume is completely sealed form exterior and it allows a complete control of its air and water parameters. All modules are connected in parallel with a double air purification system that delivers a permanent air flow. This setup is expected to provide a model experiment, able to test important processes in the interaction rock-life at grain-to- molecular scale.

Zaharescu, D. G.; Dontsova, K.; Burghelea, C. I.; Chorover, J.; Maier, R.; Perdrial, J. N.

2012-12-01

57

Polygonally cracked Kikkou-boulder and rock weathering in Yakushima, Japan  

NASA Astrophysics Data System (ADS)

In Yakushima, southwestern Japan, granitic and sedimentary boulders are cracked polygonally on their surface. They are called Kikkou-boulders, which mean polygonal pattern in Japanese. The size of the polygonal pattern is proportional to the size of the Kikkou-boulder, therefore bigger boulder has bigger polygonal pattern. The Kikkou-boulders show a concentric crust and core structure, which can be distinguished by the difference of the color. Porosity of the core is higher than the crust. Under microscope, more plagioclase minerals, in the core of Kikkou-boulder, have changed into some clay minerals. The depth of the polygonal cracking reaches the boundary between the crust and core structure. Therefore, polygonal cracking might be generated from the structure. Based on the field observations, the Kikkou-boulders would be a kind of core-stones, which are ellipsoidal blocks separated from bedrock by the cause of weathering. It is also suggested that the polygonal cracking is generated from the weathering of the rock. The core of the boulders have high porosity than the crust, therefore the weathering might be highly progressed in the core of the boulders. Highly weathered core will have high density of water or clay minerals, which cause the expansion of the core. The expansion of the core generates the extension of the surface of the boulder, therefore the crust should be cracked polygonally.

Fujii, Y.; Takemura, T.; Takahashi, M.

2006-12-01

58

Measured effects of desert varnish on the mid-infrared spectra of weathered rocks as an aid to TIMS imagery interpretation  

Microsoft Academic Search

The thermal infrared spectral properties (7-12 ?m) of natural rock surfaces from Silver Lake, CA, are discussed. Although the reflectance of weathered rocks is largely a function of the quartz content in rocks, the presence of desert varnish (clay coating) on rocks reduces the reflectance and spectral contrast with features unique to the rock spectra persisting if varnish is thin.

Benoit Rivard; Shelley B. Petroy; John R. Miller

1993-01-01

59

Weathering damage evaluation of rock properties in the Bunhwangsa temple stone pagoda, Gyeongju, Republic of Korea  

NASA Astrophysics Data System (ADS)

The stone pagoda of the Bunhwangsa temple in Republic of Korea was made of piling small brick-shaped stones. The majority of stone bricks are andesitic rocks with variable geneses. Rock properties of the pagoda roof suffer partial significant deterioration, such as multiple peel-offs, exfoliation, onion-peel-like decomposition, cracks forming round lines and falling-off stone pieces. The stylobates and tabernacles at the four corners are composed of granitic rocks, which are heavily contaminated by lichens and mosses. Some of these contamination marks show dark black or yellowish brown colors by inorganic secondary hydrates. The four tabernacles and northern face of the pagoda body have been exposed to relatively high humidity, which causes light gray efflorescence as stalactites between the northern and western sides of the body. The efflorescences are composed of calcite, gypsum and clay minerals. The stone lion statues at the southeast and northeast corners are made of alkali granite, while the others are lithic tuff. Total rock properties of the pagoda consist of 9,708 stone bricks. Among them, 11.0% are fractured, 6.7% are fallen off, and 7.0% show considerable surface efflorescence, which shows that the pagoda has been highly deteriorated by physical, chemical and biological weathering. The authors strongly suggest long-term monitoring and comprehensive conservation researches.

Lee, Chan Hee; Yi, Jeong Eun

2007-06-01

60

Weather.  

ERIC Educational Resources Information Center

This theme issue of "The Goldfinch" focuses on weather in Iowa and weather lore. The bulletin contains historical articles, fiction, activities, and maps. The table of contents lists: (1) "Wild Rosie's Map"; (2) "History Mystery"; (3) "Iowa's Weather History"; (4) "Weather Wonders"; (6) "Seasonal Jobs"; (7) "Fiction: Winter Courage"; (8) "Stayin'…

Ruth, Amy, Ed.

1996-01-01

61

Mechanical Weathering  

NSDL National Science Digital Library

This activity was designed to give students an opportunity to realize that all rocks weather mechanically and each specific rock type has its own particular rate of weathering. Students discover that mechanical weathering is the process of breaking down bedrock into smaller fragments by physical as opposed to chemical means and that rock weathering, although it seems to occur slowly in human terms, is an extremely significant part of the rock cycle. They will learn that weathered rock materials are called sediments and are the structural basis for soils and can also be compacted into sedimentary rock. Students will realize that rock weathering rates vary widely depending on mineral content, texture, rock type, and climate and that differential weathering (varying weathering rates for two or more rock types in physical contact with each other) has given rise to some of the world's most breathtaking scenery.

62

Long-wave infrared hyperspectral imagery of weathering trajectories on Hawaiian basaltic rock  

NASA Astrophysics Data System (ADS)

A long wave infrared (LWIR) hyperspectral imager, the University of Hawaii's Airborne Hyperspectral Imager (AHI), was used to relate systematic changes in LWIR spectral features to weathering trajectories on the surfaces of basaltic rocks. Kahle and others proposed that in relation to the LWIR spectra, that devitrification of chilled glassy margins dominate the first stages of weathering, followed by the accretion of silicate coatings and the oxidation of iron[1-3]. We are using the AHI's higher spectral and special resolution to better constrain this relationship between the LWIR and weathering trajectories. The main study area was along the northern flank of Mauna Loa on the Island of Hawai'i. We collected samples ranging from a few decades to over 8000 years old. Samples a few hours to a few days old were collected from Kilauea. A Nicolet FTIR spectrometer was used to acquire reference spectra in the range of 5 to 15 ?m. Three features are readily identifiable: two narrow features (A: ~8.1?m and B: 9.1?m) and one broad feature (C: 9.5 to 13 ?m). The most striking change is in the C feature which changes from a large and dominant feature in the fresh Kilauea pahoehoe, to a subtle feature in the 1935 Mauna Loa flow. The only overall age related spectral change observed is the reduction of relative spectral feature intensity with increasing age. We also noted that within samples of the same age, there are some striking differences in the spectral shape.

Carlisle, Orion; Lucey, Paul G.; Sherman, Sarah B.

2005-01-01

63

Weather  

NSDL National Science Digital Library

Introduction: How much do you know about weather? What kinds of weather do we have surrounding us? What is the weather like today? You may know a lot about weather already, you may not. Either way, you will learn more now as we take a look into what causes our weather and the methods we use to record and predict it. We will all become meteorologists, which are scientists who study the atmosphere and can predict weather. Put on your raincoats, and lets started! Task: You are the resident meteorologist at a local news station. It is your job to record and predict the weather each day, and then present it that night on the evening news. Not only should you be able to show the weather that we will be experiencing right ...

Hendricks, Ms.

2007-12-06

64

Weather  

NSDL National Science Digital Library

What are the different types of weather? In this project you will compare different types of weather by drawing pictures and making it into a flip book. First you will begin by learning about the different types of weather. Read about each topic. Then get together with your partner and draw a picture of each type of weather. 1. Thunder storm Thunder storm Thunder storm Kids 2. Lightning Lightning Lightning picture 3. Tornado Tornadoes Tornado Kids 4. ...

Jennie, Miss

2009-10-22

65

Chemical weathering on Mars - Thermodynamic stabilities of primary minerals /and their alteration products/ from mafic igneous rocks  

NASA Technical Reports Server (NTRS)

Chemical weathering on Mars is examined theoretically from the standpoint of thermodynamic equilibrium between primary rock-forming minerals and the atmospheric gases O2, H2O, and CO2. The primary minerals considered are those common to mafic igneous rocks and include olivine, pyroxene, plagioclase, magnetite, troilite, pyrrhotite, and apatite. The importance of kinetics and reaction mechanisms in controlling possible weathering processes on Mars is discussed within the limits of currently available data, and the possible influence of liquid water on Martian weathering processes is evaluated where appropriate. For gas-solid weathering of mafic igneous rocks at the Martian surface, it is concluded that upon attainment of thermodynamic equilibrium: (1) oxides and carbonates should dominate the mineral assemblage of weathering products; (2) hematite rather than goethite should be the stable mineral form of Fe (III); (3) FeSO4 or FeSO4.H2O could be the stable weathering product of iron sulfides in the absence of liquid water; and (4) kaolinite is apparently the only clay mineral that should be thermodynamically stable over all ranges of temperature and water-vapor abundance at the Martian surface.

Gooding, J. L.

1978-01-01

66

Controls on Weathering of Pyrrhotite in a Low-Sulfide, Granitic Mine-Waste Rock in the Canadian Arctic  

NASA Astrophysics Data System (ADS)

Increased environmental risk is incurred with expansion of mineral extraction in the Arctic. A greater understanding of geochemical processes associated with hard-rock mining in this cold climate is needed to evaluate and mitigate these risks. A laboratory and in-situ experiment was conducted to examine mineral weathering and the generation of acid rock drainage in a low-sulfide, run-of-mine waste rock in an Arctic climate. Rock with different concentrations of sulfides (primarily pyrrhotite [Fe7S8] containing small amounts of Co and Ni) and carbonates were weathered in the laboratory and in-situ, large-scale test piles to examine leachate composition and mineral weathering. The relatively larger sulfide-containing rock produced sufficient acid to overcome carbonate buffering and produced a declining pH environment with concomitant release of SO4, Fe, Co, and Ni. Following carbonate consumption, aluminosilicate buffering stabilized the pH above 4 until a reduction in acid generation. Results from the laboratory experiment assisted in determining that after consumption of 1.6 percent of the total sulfide, the larger sulfide-concentration test pile likely is at an internal steady-state or maximal weathering rate after seven years of precipitation input and weathering that is controlled by an annual freeze-thaw cycle. Further weathering of the test pile should be driven by external factors of temperature and precipitation in this Arctic, semi-arid region instead of internal factors of wetting and non-equilibrium buffering. It is predicted that maximal weathering will continue until at least 20 percent of the total sulfide is consumed. Using the identified evolution of sulfide consumption in this Arctic climate, a variable rate factor can now be assessed for the possible early evolution and maximal weathering of larger scale waste-rock piles and seasonal differences because of changes in the volume of a waste-rock pile undergoing active weathering due to the freeze-thaw cycle. Such rate factors are necessary to predict acid rock drainage and implement best management practices to minimize environmental impacts. To better understand the early geochemical evolution of the waste rock, sulfide minerals from different periods in the experiments were analyzed for discrete mineral characteristics indicative of a weathered state. Element transfer from the mineral to aqueous phase is transport limited because of the formation of Fe-(oxy)hydroxide weathered rims that can be an inhibitor of dissolution. Application of various x-ray spectroscopy techniques indicated that pyrrhotite transforms to marcasite [FeS2] prior to formation of Fe(II)-(oxy)hydroxides and further to Fe(III)-hydroxide/oxides. Iron appears to migrate through the weathered rims leaving the S-rich layer behind, and oxygen likely is retarded from migrating inward with formation of Fe(III) species. As these Fe-mineral transformations occur, they influence the retention of the secondary metals such as Co and Ni that preferentially remain in the +2 oxidation state and may leave the system as hydroxides, oxides, and sulfates. Understanding mineral evolution in this climate assists in adjusting appropriate rate factors for temporal changes in element release from the weathering of the pyrrhotite.

Langman, J. B.; Holland, S.; Sinclair, S.; Blowes, D.

2013-12-01

67

Excavatability Assessment of Weathered Sedimentary Rock Mass Using Seismic Velocity Method  

SciTech Connect

Seismic refraction method is one of the most popular methods in assessing surface excavation. The main objective of the seismic data acquisition is to delineate the subsurface into velocity profiles as different velocity can be correlated to identify different materials. The physical principal used for the determination of excavatability is that seismic waves travel faster through denser material as compared to less consolidated material. In general, a lower velocity indicates material that is soft and a higher velocity indicates more difficult to be excavated. However, a few researchers have noted that seismic velocity method alone does not correlate well with the excavatability of the material. In this study, a seismic velocity method was used in Nusajaya, Johor to assess the accuracy of this seismic velocity method with excavatability of the weathered sedimentary rock mass. A direct ripping run by monitoring the actual production of ripping has been employed at later stage and compared to the ripper manufacturer's recommendation. This paper presents the findings of the seismic velocity tests in weathered sedimentary area. The reliability of using this method with the actual rippability trials is also presented.

Bin Mohamad, Edy Tonnizam; Noor, Muhazian Md; Isa, Mohamed Fauzi Bin Md.; Mazlan, Ain Naadia [Department of Geotechnics and Transportation, Faculty of Civil Engineering, Universiti Teknologi Malaysia, 81310 UTM Skudai. Johor (Malaysia); Saad, Rosli [Universiti Sains Malaysia, Penang (Malaysia)

2010-12-23

68

Air temperature-driven CO2 consumption by rock weathering at short timescales: Evidence from a Holocene lake sediment record  

NASA Astrophysics Data System (ADS)

The role that air temperature plays in the interaction between atmospheric CO2 levels and continental rock weathering at relatively short time scales is still a matter of debate. Laboratory studies reveal a strong dependence of mineral dissolution on temperature, but field comparisons among watersheds under different climate conditions often indicate correlations with other environmental factors. Using a paleolimnological approach, here we show that there has been an extremely good coupling between rock weathering, water alkalinity (CO2 consumption), and air temperature during the last 10,000 years at sub-millennial time scales in a small watershed of silicate bedrock and scarce vegetation. The calculation of apparent activation energy for the weathering reaction (as a means to describe the temperature dependence of the process) provides a value (Ea = 67 ± 7 kJ mol-1) that is comparable to those found for silicate rocks similar to those in the watershed in laboratory experiments and some field studies. Our results provide evidence that regulatory constraints between air temperature, atmospheric CO2 and silicate rock weathering can be fine-tuned at geological timescales and may not be negligible in the current context of global change.

Catalan, Jordi; Pla-Rabés, Sergi; García, Joan; Camarero, Lluís

2014-07-01

69

Geochemistry of Neogene sedimentary rocks from Borneo Basin, Malaysia: implications on paleo-weathering, provenance and tectonic setting  

NASA Astrophysics Data System (ADS)

Multi-element geochemistry and mineralogy are used to characterize the chemical composition, degree of paleo-weathering, provenance and tectonic settingsof the Neogene sedimentary rocks of Borneo Basin from east Malaysia. The sedimentary rocks are classified as extremely weathered sandstones (i.e. wacke, arkose, litharenite, Fe-sandstone and quartz arenite). Higher values of both weathering indices of alteration (i.e. CIA>83 and PIA>89) suggest that the sandstones have undergone extreme chemical weathering. Absence of any feldspar in the mineralogical analysis indicates its degradation during the weathering. Except for the quartz arenite, all other sandstones are characterized by post-depositional K-metasomatism and zircon enrichment through sediment recycling. The geochemical characteristics suggest a mixed-nature provenance for the sandstones with contribution coming from both felsic and mafic igneous rocks. Enriched Cr in quartz arenite and Fe-sandstone are related to contribution from ophiolite or fractionation of Cr-bearing minerals. The inferred tectonic settings are variable and suggest a complex nature of tectonic environment in the basin.

Ramasmay, N.; Roy, P.; MP, J.; Rufino, L.; Franz, L. K.; Viswanathan, P. M.

2013-05-01

70

Weathering  

NSDL National Science Digital Library

This interactive Flash resource provides information regarding physical and chemical weathering at an introductory physical geology or Earth science level. It includes animations, diagrams, and supplementary information and is suitable for high school or undergraduate students.

Smoothstone; Mifflin, Houghton

71

Worldwide distribution of continental rock lithology: Implications for the atmospheric\\/soil CO2 uptake by continental weathering and alkalinity river transport to the oceans  

Microsoft Academic Search

The silicate rock weathering followed by the formation of carbonate rocks in the ocean, transfers CO2 from the atmosphere to the lithosphere. This CO2 uptake plays a major role in the regulation of atmospheric CO2 concentrations at the geologic timescale and is mainly controlled by the chemical properties of rocks. This leads us to develop the first world lithological map

Philippe Amiotte Suchet; Jean-Luc Probst; Wolfgang Ludwig

2003-01-01

72

Studies of Fe/sup 2 +/. -->. Fe/sup 3 +/ transitions during the process of rock weathering by nuclear gamma-resonance spectroscopy  

SciTech Connect

This paper presents a method for the mineral and weathering assessment of rocks and carbonaceous matter based in gamma spectroscopy and transitions between iron ions. The method is applied to rocks collected near the Teberda preserve. Four latitudinal bands of rocks parallel to the Greater Caucasus Ridge are identified in this territory. Isomer shift and hyperfine parameters of the Moessbauer spectra are given.

Vasil'ev, S.P.; Babanin, V.F.; Solov'ev, A.A.

1986-11-01

73

Characterizing the process and quantifying the rate of subaerial rock weathering on desert surfaces using roughness analysis  

NASA Astrophysics Data System (ADS)

Subaerial weathering of rocks is a common process observed on desert surfaces on Earth and other planetary terrestrial surfaces such as on Mars. On Earth, this weathering process has been previously identified as one of the key erosion agent driving geomorphic surface evolution and the development of desert pavements. And yet, fundamental aspects of the process, such as the relative contribution of the different weathering modes that drive it (e.g., mechanical breakdown of rocks, chemical weathering, aeolian abrasion and exfoliation) as well as the rate by which this weathering process occurs have not been systematically examined. Here, we present a new approach for quantitatively addressing these fundamental aspects of process geomorphology on desert surfaces. We focus here on co-genetic desert alluvial surfaces of different ages, i.e. alluvial chronosequences, which provide excellent recorders for the evolution of boulder-strewn surfaces into smooth desert pavements through in-situ subaerial weathering of rocks. Our approach combines independent measures of two different surface attributes: High resolution (mm-scale) 3D ground-based laser scanning (LiDAR) of surface micro-topography, and numerical dating of surface age. Roughness analysis of the LiDAR data in power spectral density (PSD) space allows us to characterize the geometric manifestation of rock weathering on the surface and to distinguish between the different weathering modes. Numerical age constraints provide independent estimates for the time elapsed since the process began. Accordingly, we are able to constrain surface roughness evolution on alluvial fan desert chronosequences through time, and present PSD analysis of surface roughness as a new quantitative tool to examine the process of subaerial rock weathering in desert environments. In this study we present results from two late Quaternary alluvial chronosequences along the Dead Sea Transform in the hyper-arid Negev desert of southern Israel. LiDAR scanning was applied on representative areas (~30-50 m2) of 10 separate surfaces ranging from rough Holocene surfaces to fairly smooth surfaces with well-developed pavements displaying an OSL age of 87 kyr. We find typical and recurring time-dependent changes in the offset as well as shape of the PSD curves in both chronosequences: PSD offset is continuously reduced over time reflecting the overall reduction in the amplitude of roughness at all wavelengths. The PSD curves display progressive moderation of slopes at the longer wavelengths with the moderation point itself systematically shifted to shorter wavelengths. This characteristic evolution of PSD offset and slope moderation at longer wavelengths reflects the typical break up of boulder-sized clasts through time as the surfaces mature into well-developed desert pavements and points towards mechanical breakdown as the dominant weathering mode. In addition, we are able to determine the rate by which the larger clasts are removed from the system. We build on these new insights into process and rate of rock weathering to propose PSD analysis of surface roughness as a complementary method for constraining the age of desert alluvial surfaces in places where 'conventional' dating cannot be applied.

Mushkin, Amit; Sagy, Amir; Trabelci, Eran

2013-04-01

74

Mismatched Physical and Chemical Weathering of Rocks on Mars: Clues to Past Climate  

NASA Astrophysics Data System (ADS)

Here we quantify the degree of weathering experienced by the Adirondack-class basalts at the MER Spirit site by performing comparative analyses on the strength and chemistry of a series of progressively weathered Columbia River Basalt samples.

Thomson, B. J.; Hurowitz, J. A.; Baker, L. L.; Bridges, N. T.; Lennon, A.; Paulson, G.; Zacny, K.

2014-07-01

75

Rocks  

NSDL National Science Digital Library

This year we are going to learn about rocks. Do you like to collect rocks? Rocks are the most common material on earth. We will learn about the parts that make up the rocks and sort rocks based upon color, hardness, texture, layering, and particle size. So you want to learn about rocks? Go to Intro to Rocks for some fascinating facts about rocks! Now lets learn about some of the different kinds of rocks. Igneous Rocks Metamorphic Rocks Sedimentary Rocks Click here to see the differences between the types of rocks that you have learned about What Type Of Rock Do I Have?. After doing all the activities above, ...

Woodruff, Mrs.

2010-06-21

76

Groundwater flows in weathered crystalline rocks: Impact of piezometric variations and depth-dependent fracture connectivity  

NASA Astrophysics Data System (ADS)

Groundwater in shallow weathered and fractured crystalline rock aquifers is often the only perennial water resource, especially in semi-arid region such as Southern India. Understanding groundwater flows in such a context is of prime importance for sustainable aquifer management. Here, we describe a detailed study of fracture properties and relate the hydraulic connectivity of fractures to groundwater flows at local and watershed scales. Investigations were carried out at a dedicated Experimental Hydrogeological Park in Andhra Pradesh (Southern India) where a large network of observation boreholes has been set up. Twenty-height boreholes have been drilled in a small area of about 18,000 m2 in which borehole loggings and hydraulic tests were carried out to locate the main flowing fractured zones and investigate fractures connectivity. Several hydraulic tests (nineteen slug tests and three pumping tests) performed under two water level conditions revealed contrasting behavior. Under high water level conditions, the interface including the bottom of the saprolite and the first flowing fractured zone in the upper part of the granite controls groundwater flows at the watershed-scale. Under low water level conditions, the aquifer is characterized by lateral compartmentalization due to a decrease in the number of flowing fractures with depth. Depending on the water level conditions, the aquifer shifts from a watershed flow system to independent local flow systems. A conceptual groundwater flow model, which includes depth-dependent fracture connectivity, is proposed to illustrate this contrasting hydrological behavior. Implications for watershed hydrology, groundwater chemistry and aquifer vulnerability are also discussed.

Guihéneuf, N.; Boisson, A.; Bour, O.; Dewandel, B.; Perrin, J.; Dausse, A.; Viossanges, M.; Chandra, S.; Ahmed, S.; Maréchal, J. C.

2014-04-01

77

External Resource: Mechanical Weathering  

NSDL National Science Digital Library

A student activity with teacher's sheet, to give the students an opportunity to realize that all rocks weather mechanically and each specific rock type has its own particular rate of weathering. Mechanical weathering is the process of breaking down bedroc

1900-01-01

78

Regolith Evolution Influences Element Redistribution During Weathering of Volcanic Rocks in Erosional, Sedentary, and Depositional Landscapes: Examples From Hawai'i, Guatemala and Southeastern Australia  

NASA Astrophysics Data System (ADS)

This study examines the weathering of volcanic rocks exemplifying each of three landscape/regolith associations (erosional, sedentary/relict/residual, and depositional), and illustrates how the regolith/landscape associations and their geomorphic evolution influence the geochemical evolution of the regolith. In erosional landscapes, the rate of physical erosion exceeds the rate of chemical weathering of rock to altered regolith, and surface materials consist of fresh or minimally weathered bedrock. Recent basalts (<4ka) from Hawai'i have weathered slightly and have accumulated no weathering rinds, saprolite, or allochthonous regolith over their brief exposure history. Whole-rock geochemistry is not affected by the small amount of chemical weathering. Leaching has been insufficient for differential removal of elements, and there are no elemental sources outside of the nearly fresh outcrops from which elements might have been introduced into the exposed volumes. In sedentary/relict/residual landscapes, the rate of chemical weathering equals or exceeds the rate of physical erosion, and surface material consists of deeply weathered saprolite. Some volcanic rocks of Plio-Pleistocene age from Hawai'i and Guatemala have experienced spheroidal or corestone weathering, in which corestones of minimally weathered rock are surrounded by concentric saprolitic shells and saprolite derived from the decomposition of the volcanic rock. Many major elements and some minor elements (REE) are depleted from the saprolitic portions of these regoliths. However, several of these minor elements (REE) are enriched in the inner portions of corestone-shell complexes, suggesting that these minor elements and REE leached from saprolite are transferred within the regolith to secondary minerals formed during incipient weathering of the corestones. In depositional landscapes, the surficial material consists of sediment (colluvial, fluvial/alluvial, or aeolian). Tertiary volcanic rocks of the Monaro Volcanic Province (New South Wales, Australia) were emplaced in fluvial-lacustrine environments and almost immediately covered by fine-grained clastic sediment. The jointed flows weathered spheroidally. Corestones have essentially fresh major element and REE signatures. However, Zr (probably redistributed physically from the fine-grained sediment) exhibits systematic absolute enrichment with progressive weathering in the Monaro corestone-shell complexes. Weathering of volcanic rocks results in geochemical trends that differ systematically with the presence, nature, and extent of development of associated regolith. Geochemical patterns of element depletion and enrichment in individual samples and suites of samples can only be properly interpreted if the regolith/landscape context of the samples is taken into account.

Velbel, M. A.; Patino, L. C.; Price, J. R.; Wade, J. A.

2004-12-01

79

Weathering Animation  

NSDL National Science Digital Library

Weathering is the term that describes all the processes that break down rocks in the environment near the Earth's surface. This module will help you to understand two weathering processes: mechanical and chemical.

2002-01-01

80

A study of the depth of weathering and its relationship to the mechanical properties of near-surface rocks in the Mojave Desert  

USGS Publications Warehouse

Weathered granite extends 70 m deep at Hi Vista in the arid central Mojave Desert of southern California. The low strength of this granite is due to the alteration of biotite and chlorite montmorillonite. Deep weathering probably occurs in most granites, although we cannot rule out some anomalous mechanisms at Hi Vista. Geophysical instruments set in these slightly altered rocks are limited by the unstable behavior of the rocks. Thus, tectonic signals from instruments placed in shallow boreholes give vague results. Geophysical measurements of these weathered rocks resemble measurements of granitic rocks near major faults. The rheology of the rocks in which instruments are placed limits the useful sensitivity of the instruments. ?? 1985 Birkha??user Verlag.

Stierman, D. J.; Healy, J. H.

1985-01-01

81

Host-Mineral Weathering and REE Redistribution During Weathering of Volcanic Rocks in Sedentary Landscapes: Examples from Hawai'i and Guatemala  

NASA Astrophysics Data System (ADS)

During weathering Hawai'ian and Guatemalan basalts, REE are mobilized from extensively weathered regolith into incipiently weathered portions of the corestones, resulting in increased concentrations of these elements in minimally weathered basalts.

Velbel, M. A.; Patino, L. C.; Wade, J. A.; Donatelle, A. R.; Price, J. R.

2007-03-01

82

Subdivision of Late Pleistocene Moraines in the Cordillera Blanca, Peru, Based on Rock-Weathering Features, Soils, and Radiocarbon Dates  

NASA Astrophysics Data System (ADS)

The progressive development of unusual rock-weathering features and soils and minimum-limiting radiocarbon dates provide a basis for subdividing four groups of late Pleistocene moraines on the west side of the Cordillera Blanca, northern Peru (9°20'1°000'S, 77°10'-77°30'W). Boulders on the youngest late Pleistocene moraines have 10 to 14-cm-tall weathering posts; soils on these moraines yield mean profile development index (PDI) values of 0.05 ± 0.04 (±1?). These moraines date between ca. 13,500 and 9700 ± 500 yr B.P., older than previously postulated. The next older moraines have boulders with weathering-post heights between 20 and 25 cm and soils with PDI values of 0.08 ± 0.07, and were deposited prior to 13,280 ± 190 yr B.P., probably during the last glacial maximum (marine isotope stage 2). Moraines from an older glaciation have boulders with weathering posts between 39 and 50 cm high, soils that yield PDI values of 0.21 ± 0.07, and are older than 19,700 ± 340 yr B.P. Boulders on moraines from a still older glaciation have lost ca. 50% of their above-ground volume, and have weathering posts between 62 and 70 cm high. PDI values for soils on these moraines are 0.32 ± 0.06. Linear and logarithmic models of weathering-post and soil development with time are used to estimate minimum and maximum ages for the two oldest moraine groups. Linear models suggest that the second oldest moraines are between ca. 20,500 and 46,500 yr B.P., and that the oldest moraines are between ca. 29,000 and 72,000 yr B.P. In contrast, logarithmic models suggest ages of greater than ca. 75,500 yr B.P. and greater than ca. 500,000 yr B.P., respectively.

Rodbell, Donald T.

1993-03-01

83

Nutrient Release from Weathering of Purplish Rocks in the Sichuan Basin, China 1 1 Project supported by the National Basic Research Program of China (No. 2003CB415202) and the National Natural Science Foundation of China (Nos. 40571093 and 49601009)  

Microsoft Academic Search

Purplish soils having high fertility with mineral nutrients inherited from the parent rock are widely distributed in the hills along the Yangtze River, especially in the Sichuan Basin. Pot and field weathering experiments were conducted to mimic rock weathering and nutrient release processes in order to better understand soil fertility and nutrient compensation. Three types of purplish rock formations formed

Bo ZHU; Tao WANG; Xiang YOU; Mei-Rong GAO

2008-01-01

84

Rock and stone weathering at Citadel fortifications, Gozo (Malta): benefits from terrestrial laser scanning combined with conventional investigations  

NASA Astrophysics Data System (ADS)

Military architecture heritage is frequently built on rock masses affected by slope instability and weathering processes, which progressively undermine the foundations and cause collapses and toppling of the masonries. The latter can be also weakened by alteration of the stone surfaces, as a consequence of the interactions with the local environmental conditions. These conservation issues are emphasized for those sites, whose susceptibility to structural damages is also due to the similarity between the lithotypes constituting the geologic substratum and the construction materials. Effective solutions for the protection from such a type of phenomena can be achieved if the whole "rock mass - built heritage system" is analyzed. In this perspective, we propose a new approach for the study of the weathering processes affecting historic hilltop sites, taking benefits from the combination of terrestrial laser scanning (TLS) and conventional investigations, the latter including geotechnical and minero-petrographic analyses. In particular, the results here presented were obtained from specific tests on the fortifications of Citadel, Gozo (Malta), performed in co-operation with the Restoration Unit, Works Division, Maltese Ministry for Resources and Rural Affairs and the private company Politecnica Ingegneria e Architettura. The Citadel fortifications are built at the top of a relatively stiff and brittle limestone plate, formed by Upper Coralline Limestone (UCL) and overlying a thick Blue Clay (BC) layer. Differential weathering creates extensively fractured ledges on the cap and erosion niches in the strata beneath, thereby favouring block detachment, even rockfall events, such as the last one occurred in 2001. The locally quarried Globigerina Limestone (GL), historically employed in restoration masonries, is also exposed to alveolization and powdering, and several collapses damaged the underwalling interventions. Since the erosion pattern distribution suggested a correlation with the structural setting of the rock mass and the mineralogical properties of the limestones, an overall weathering study was carried out, by combining surface surveys with analyses of the inner structure. A holistic TLS point cloud of Citadel, produced by Consorzio Ferrara Ricerche of the University of Ferrara and made available by the Restoration Unit, was exploited to perform a 3D quantitative kinematic analysis of the entire rock mass. Each sector was classified in relation to the probability of occurrence of instability mechanisms, among which plane failure, block toppling and wedge failure. The latter was found associated with the highest index measured (30%), followed by the flexural toppling mechanism (17%), providing a confirmation to the field survey and the results of geotechnical analyses. The integration with geologic and diagnostic investigations (e.g., boreholes, thin section observations) highlighted the intrinsic weaknesses of the rocks and stones to weathering, with a quite unexpected higher susceptibility to erosion and disaggregation characterizing the inner layers. Hence, the textural appearance of the erosion surfaces, the rock/stone structural properties and the TLS-based classification of the cliff sectors were mutually correlated, and the most unstable areas were mapped. As main implication for the conservation, on site monitoring system (i.e., biaxial inclinometers and crack gauges) was installed and targeted restorations have been properly designed.

Tapete, D.; Gigli, G.; Mugnai, F.; Vannocci, P.; Pecchioni, E.; Morelli, S.; Fanti, R.; Casagli, N.

2012-04-01

85

Storage and release of fossil organic carbon related to weathering of sedimentary rocks  

Microsoft Academic Search

The biogeochemical carbon cycle, which plays an undeniable role in global climate change, is defined both by the size of carbon reservoirs (such as the atmosphere, biomass, soil and bedrock) and the exchange between them of various mineral and organic carbon forms. Among these carbon forms, fossil organic carbon (FOC) (i.e., the ancient organic matter stored in sedimentary rocks) is

Yoann Copard; Philippe Amiotte-Suchet; Christian di-Giovanni

2007-01-01

86

The role of disseminated calcite in the chemical weathering of granitoid rocks  

Microsoft Academic Search

Accessory calcite, present at concentrations between 300 and 3000 mg kg?1, occurs in fresh granitoid rocks sampled from the Merced watershed in Yosemite National Park, CA, USA; Loch Vale in Rocky Mountain National Park CO USA; the Panola watershed, GA USA; and the Rio Icacos, Puerto Rico. Calcite occurs as fillings in microfractures, as disseminated grains within the silicate matrix,

Art F White; T HOMAS D. BULLEN; DAVISON V. VIVIT; MARJORIE S. SCHULZ; DAVID W. CLOW

1999-01-01

87

Chemical weathering of silicate rocks as a function of elevation in the southern Swiss Alps  

Microsoft Academic Search

Surface water and soil samples were collected from a series of small catchments on granitic gneiss in the Canton of Ticino in southern Switzerland. Elevations of the sampling points ranged from 220 to 2400 m; vegetation varied correspondingly from deciduous forest through coniferous forest to alpine pasture and essentially unvegetated rock and talus. Annual precipitation averaged 1.9 to 2.4 m.

James I. Drever; Jürg Zobrist

1992-01-01

88

Rocks  

NSDL National Science Digital Library

This slide show provides basic information on the three major rock types and the rock cycle. Diagrams of the rock cycle explain the processes and changes that connect the three rock types and illustrate how one type can be changed into another. Each of the three types (sedimentary, igneous, metamorphic) are described and illustrated with photographs. Addresses for websites with additional information are also included.

Passow, Michael

89

In search for coastal amplification of rock weathering in polar climates - pilot Schmidt hammer rock tests surveys from sheltered fjords of Svalbard and tsunami-affected coasts of Western Greenland.  

NASA Astrophysics Data System (ADS)

Recent decade has seen the major advance in Arctic coastal geomorphology due to research progress along ice-rich permafrost coastlines of Siberia, Alaska and NW Canada. On the contrary little attention was paid to Arctic rocky coastlines and their response to the reduction of sea ice cover and increased number of storms reaching Arctic region. In this paper I present results from a pilot survey of rock resistance using Schmidt Hammer Rock Tests across rocky cliffs and shore platforms developed in: - sheltered bays of Billefjorden, Svalbard characterised by prolonged sea-ice conditions and very limited operation of wave and tidal action - Vaigat Strait and Isfjorden in W Greenland influenced by landslide-triggered tsunamis and waves induced by ice-berg roll events. The aim of a pilot study was to test the hypothesized coastal impact on the rate of rock weathering in polar climates. To do so I characterise the changes in the rock resistance on the following coastal landforms: - modern and uplifted wave-washed abrasion platforms- focusing on a relation between the degree of rock surface weathering and the distance from the shoreline as well as thickness of sediment cover on shore platform surface - modern and uplifted rocky cliffs - focusing on a relation between the degree of rock surface weathering and the distance from the shoreline as well as difference in height above the sea level and relation to rock lithology. The results present another line of argument supporting intensification of rock weathering processes in the Arctic coastal zone. This work is a contribution to the National Science Centre in Poland research project no. 2011/01/B/ST10/01553.

Strzelecki, Matt

2014-05-01

90

Use of hydraulic tests at different scales to characterize fracture network properties in the weathered-fractured layer of a hard rock aquifer  

Microsoft Academic Search

The hydrodynamic properties of the weathered-fractured layer of a hard-rock pilot watershed in a granitic terrain are characterized using hydraulic tests at different scales. The interpretation of numerous slug tests leads us to characterize the statistical distribution of local permeabilities in the wells. The application of flowmeter profiles during injection tests determines the vertical distribution of conductive fracture zones and

J. C. Maréchal; B. Dewandel; K. Subrahmanyam

2004-01-01

91

Weathering of Basaltic Rocks from the Gusev Plains up into the Columbia Hills from the Perspective of the MER Mossbauer Spectrometer  

NASA Technical Reports Server (NTRS)

Rocks on the ejecta blanket of Bonneville crater and along Spirit s traverse over the Gusev plains towards the Columbia Hills are angular and strewn across the surface. They have a basaltic composition [1,2], and their Mossbauer spectra are dominated by an olivine doublet [1]. The ubiquitous presence of abundant olivine in rocks and in surrounding soil suggests that physical rather than chemical weathering processes currently dominate the plains at Gusev crater [1]. However, MB spectra of rocks and outcrops in the Columbia Hills suggest more aggressive alteration processes have occurred. Ascending into the hills, Spirit encountered outcrop and rocks exhibiting layered structures. Some scattered rocks at the foot of the Columbia Hills appeared "rotten" or highly altered by physical and/or chemical processes (fig. 1). Mossbauer spectra of those rocks show a decrease in olivine accompanied by an increase in the Fe-oxides magnetite, hematite, and nanophase Fe3+ -oxides (fig. 2), suggesting that chemical weathering processes in the presence of water have altered these rocks and outcrops.

Schroeder, C.; Klingelhoefer, G.; Morris, R. V.; Rodionov, D. S.; deSouza, P. A.; Ming, D. W.; Yen, A. S.; Gellert, R.; Bell, J. F., III

2005-01-01

92

Rocks  

NSDL National Science Digital Library

In this activity students will use sample sets of igneous, metamorphic, and sedimentary rocks to learn how to identify the major rock types. They will write the key characteristics that would help them identify each of the rocks on the list. They will find and copy an image of each from the "Volcano World" slide show and answer the questions at the end of this activity. As a result of this lesson students will learn how to identify major rock types through their characteristic properties, especially through the Earth Science Reference Table identification charts, and understand how to find out what types of rocks can be found in a particular area using geologic maps, especially the one in the Earth Science Reference Table.

Lamont-Doherty Earth Observatory, The E.

93

Weathering of Igneous, Metamorphic, and Sedimentary Rocks in a Semi-arid Climate - An Engineering Application of Petrology  

NASA Astrophysics Data System (ADS)

Over the last 10 years, analytical methods have been introduced to students in CSM's undergraduate geological engineering program through a multi-year and multi-course approach. Beginning with principles and simple applications of XRD and SEM in sophomore Mineralogy and building on these skills in subsequent junior and senior year courses, geological engineers acquire proficiency in analytical methods. Essential workplace skills are thus acquired without adding an extra course in the undergraduate program. The following exercise is completed by juniors in an integrated Ig.-Met.-Sed. petrology course. The identification of clay mineral assemblages in soils provides a unique opportunity to demonstrate how basic principles of petrology and geochemistry are applied to engineering design criteria in construction site preparation. Specifically, the problem investigates the conditions leading to the formation of smectite in soils and the resulting construction risk due to soil expansion. Students examine soils developed on igneous, metamorphic, and sedimentary rocks near Denver, Colorado. The field locations are areas of suburban growth and several have expansive soil problems. The 2-week exercise includes sample collection, description, and preparation, determining clay mineralogy by XRD, and measurement of Atterberg Plasticity Indices. Teaching materials may be found at: http://serc.carleton.edu/NAGTWorkshops/petrology03/. This exercise accomplishes three objectives: First, skills in XRD analysis are developed by introducing students to concepts of particle size separation, particle orientation, and sequential analysis steps which are standard practices in clay characterization. Second, lecture material on the geochemistry of weathering of different rock types is reinforced. Students interpret the origin of clay mineral assemblages developed in soils derived from Precambrian gneisses, lower Paleozoic feldspathic sandstones, upper Paleozoic marine shales, and Tertiary basalts and volcaniclastics. Third, the role of petrologic characterization in site engineering is demonstrated. Students use Atterberg Limits measurements in conjunction with soil mineralogy to assess swelling potential and to design soil treatment needs for each building site.

Harrison, W. J.; Wendlandt, R. F.

2003-12-01

94

Rocking Changes  

NSDL National Science Digital Library

In this earth science activity, learners conduct a series of short experiments to explore how rocks change. Learners will examine the components of the rock cycle as well as how rocks can change over time due to weathering, erosion, pressure and heat. In particular, learners will model igneous, sedimentary, and metamorphic rocks.

Workshop, Mission S.

2013-01-01

95

Schmidt Hammer studies in the maritime Antarctic: Application to dating Holocene deglaciation and estimating the effects of macrolichens on rock weathering  

NASA Astrophysics Data System (ADS)

In order to contribute to the reconstruction of the deglaciation history of the Marguerite Bay area (~ 68°S, Maritime Antarctic) and to estimate the rock weathering rate in this Antarctic sector, 28 sites (7 on Rothera Point and 21 on Anchorage Island) were characterised using Schmidt Hammer values. The weathering effect of two of the most widespread species of macrolichens in this area (Usnea sphacelata and Umbilicaria decussata) was tested at 5 different sites on Rothera Point. Schmidt Hammer data, in conjunction with recent 14C age, suggest a deglaciation age for the Marguerite Bay area of around 12 ka, and an average uplift rate of 5.4 mm year- 1 on Anchorage Island for the period between 3.3 and 5.2 ka. The weathering rates are extremely slow (e.g. three times slower than reported in Norway). Our data confirm that lichens exert a strong impact on weathering, decreasing the Schmidt Hammer R-values on lichenised surfaces by a factor of 3-4 compared to bare rock surfaces. The effect of lichens on weathering is mainly due to edaphic conditions and the type of the lichen involved rather the period of exposure.

Guglielmin, M.; Worland, M. R.; Convey, P.; Cannone, N.

2012-06-01

96

Characterization and petrophysical properties of hydrothemally altered lacustrine volcanistic rock in Geyser Valley (Kamchatka) and its transformation by weathering  

NASA Astrophysics Data System (ADS)

Work is devoted to the study of volcano sedimentary hydrothermally altered rocks in Geyser Valley (Kamchatka peninsula, Russia). The Geyser Valley is one of the most unique nature objects in Russia. There are quite large geyser fields. The valley of the river is part of the Uson-Geysernaya depression, where hydrothermal activity is very high. Besides geysers here are hot springs, mud pots and fumarols. In the late Pleistocene (about 45-35 thousand years ago) the lake was located in the site of the modern valley of the Geysernaya river, where sediments accumulated intensively. Sedimentary material came from several sources in the form of pyroclastic flows, ash falls, was supplied by permanent and temporary water streams. The total deposit thickness reached several hundred meters. In the late Pleistocene there was breakthrough of reservoir and further conditions for the lacustrine deposits formation did not arose. Later the rocks were intensively processed by thermal water. In 2007 large landslide was formed in lower part of the Geysernaya River on their left slope. Deposits of Geysernaya (Q34grn) series and Pemsovaya (Q34pmz) series were involved in landslide displacement. The headscarp was formed up to 100 m and a length of 800 m, exposing the volcano-sedimentary section of hydrothermally altered rocks - a unique opportunity for sampling and subsequent laboratory study. Thickness of lake sediments is interbedding of coarse-grain, medium-grain, fine-grain tuffites predominantly acidic composition. The study of thin sections revealed that all samples are lithoclastic and vitroclastic hydrothermally altered tuffits. Currently, the primary minerals and volcanic glass is largely replaced by clay minerals of the smectite group. Pores and cracks are made zeolites (heulandite and clinoptilolite). All this points to the low-temperature (<200 ° C) hydrothermal conditions with a pH near neutral. Tyere are acid plagioclase and quartz in most samples The high content of smectite causes high hygroscopy of deposits. Rocks are highly porous - of 37-65%, primarily low density - 0,9-1,65 g/cm3 wave velocities - from 0.74 km/s for porous to 3.42 km/sec for dense varieties. All samples are characterized by low strength characteristics: uniaxial compressive strength - 1.2 - 21.7 MPa, uniaxial tension - 0,6-4,7 MPa. By water saturation strength decreases rapidly. Soft coefficient ranges from 0.22 to 0.57. Proving to be on the land surface as a result of slope deformation, volcanic-sedimentary hydrothermally altered rocks are destroyed quickly by precipitation and temperature fluctuations Rock turned to sand, silt and clay depending on the original composition. It was found that often weathered to clayey state tuffites inherit structural and textural features of the primary species. The composition also varies: increased content of clay minerals (to 90%), decreasing the content of zeolites (not to exceed 10%). Quartz and plagioclase form sans fraction. Physical and mechanical properties vary widely: the density of the soil increases slightly up to 1,57-1,59 g/cm3 for sands, 1,2-1,79 g/cm3 for clays, porosity of 51-52% and 49-78% respectively, moisture 22-23% and 43-98/ Clays are in a state of semi-solid to fluid. The high content of smectite determines high plastic properties. Plasticity Index varies widely from 11 to 57. Cohesion and the internal friction angle obtained from shear tests also change widely. For clayey sand grip reaches 137 kPa, internal friction angle - 17 degrees. In clay grip ranges from 13 kPa to 120 kPa, and the internal friction angle - from 11 degrees to 31 degrees. Large variation of properties of the investigated soils is explained by the inhomogeneity of volcano-sedimentary formations both vertically and laterally, varying degrees of hydrothermal alteration and of weathering, fracturing and cracks filling The obtained datas can adequately characterize the volcanic-lacustrine sediments in the valley of the Geysernaya river and use them in calculations of slope stability and for and geological mapping.

Gvozdeva, Irina; Zerkal, Oleg; Samarin, Evgeny

2013-04-01

97

Interaction of unsaturated flow and mineral weathering reactions: solution chemistry response to infiltration during a four-year constructed rock pile experiment  

NASA Astrophysics Data System (ADS)

When reduced minerals, such as pyrite, are exposed to the atmosphere by excavation or dewatering, oxidation reactions lead to the production of acidity and the release of metals. To predict the intensity and duration of the resulting mineral-water reactions and loadings to the environment one must understand the individual transport and weathering processes and their interaction. We present results from an ongoing study of unsaturated flow hydrology and mineral weathering of a low-sulfide uranium bearing waste rock from a site in northern Saskatchewan. We compare laboratory measured weathering rates with field scale observations of outflow geochemistry. Both the long term trends and short term responses to infiltrajtion events will be presented.

Beckie, R.; Smith, L.; Marcoline, J.; Wagner, K.; Nichol, C.; Stockwell, J.

2003-04-01

98

Permafrost and snow monitoring at Rothera Point (Adelaide Island, Maritime Antarctica): Implications for rock weathering in cryotic conditions  

NASA Astrophysics Data System (ADS)

In February 2009 a new permafrost borehole was installed close to the British Antarctic Survey Station at Rothera Point, Adelaide Island (67.57195°S 68.12068°W). The borehole is situated at 31 m asl on a granodiorite knob with scattered lichen cover. The spatial variability of snow cover and of ground surface temperature (GST) is characterised through the monitoring of snow depth on 5 stakes positioned around the borehole and with thermistors placed at three different rock surfaces (A, B and C). The borehole temperature is measured by 18 thermistors placed at different depths between 0.3 and 30 m. Snow persistence is very variable both spatially and temporally with snow free days per year ranging from 13 and more than 300, and maximum snow depths varying between 0.03 and 1.42 m. This variability is the main cause of high variability in GST, that ranged between - 3.7 and - 1.5 °C. The net effect of the snow cover is a cooling of the surface. Mean annual GST, mean summer GST, and the degree days of thawing and the n-factor of thawing were always much lower at sensor A where snow persistence and depth were greater than in the other sensor locations. At sensor A the potential freeze-thaw events were negligible (0-3) and the thermal stress was at least 40% less than in the other sensor locations. The zero curtain effect at the rock surface occurred only at surface A, favouring chemical weathering over mechanical action. The active layer thickness (ALT) ranged between 0.76 and 1.40 m. ALT was directly proportional to the mean air temperature in summer, and inversely proportional to the maximum snow depth in autumn. ALT temporal variability was greater than reported at other sites at similar latitude in the Northern Hemisphere, or with the similar mean annual air temperature in Maritime Antarctica, because vegetation and a soil organic horizon are absent at the study site. Zero annual amplitude in temperature was observed at about 16 m depth, where the mean annual temperature is - 3 °C. Permafrost thickness was calculated to range between 112 and 157 m, depending on the heat flow values adopted. The presence of sub-sea permafrost cannot be excluded considering the depth of the shelf around Rothera Point and its glacial history.

Guglielmin, Mauro; Worland, M. Roger; Baio, Fabio; Convey, Peter

2014-11-01

99

Rocks, Rocks, Rocks!  

NSDL National Science Digital Library

What are the three types of rocks in the earth? Miss Rogers will hand out this chart. Compare and contrast the three rock types as you read. Three-circle Venn Diagram Record what you learn for each type of rock (IGNEOUS, SEDIMENTARY, METAMORPHIC). 3 Types of Rocks Watch this video. Rock Video Read about the rock cycle. Think about what objects in our classroom could represent the rock cycle. The Rock Cycle Read over the activity we ...

Rogers, Miss

2011-10-26

100

Climate and rock weathering: a study of terrestrial age dated ordinary chondritic meteorites from hot desert regions  

NASA Astrophysics Data System (ADS)

Ordinary chondrites (OC) recovered from the desert areas of Roosevelt County, New Mexico, the Nullarbor Region of Western Australia, and the Algerian and Libyan Sahara, for which 14C terrestrial ages have been determined, were examined by 57Fe Mössbauer spectroscopy. OC were chosen as a standard sample to investigate weathering processes as their well constrained trace and bulk element chemistry, normative mineralogy and isotopic composition define a known, pre-weathering, starting composition. Given that terrestrial ages are known, it is possible to compare (initially very similar) samples that have been subsequently weathered in a range of climatic regimes from the present day to > 44 ka BP. In addition, recently fallen equilibrated OC contain iron only as Fe 0 and Fe 2+, thus the abundance of ferric iron is directly related to the level of terrestrial weathering. Mössbauer spectroscopy identifies two broad types of ferric alteration: paramagnetic phases (akaganéite, lepidocrocite, and goethite), and magnetically ordered (principally magnetite and maghemite). OC finds show a range in the percentage of total Fe existing as Fe 3+ from zero to over 80%. However, oxidation is comparable between fragments of the same OC separated since their time of fall (i.e., paired meteorites). Our results indicate several features of meteorite weathering that may result from climatic or geomorphologic conditions at the accumulation site: (1) Saharan samples are, overall, less weathered than non-Saharan samples, which may be related to the relatively recent age (ca. 20 ka) of the Saharan accumulation surface; (2) broad differences between sites in the rate of weathering, arising from regional differences in climate; (3) consistent differences in the weathering products between samples that fell during humid periods and those that fell during more arid periods (those falling during humid periods contain a higher proportion of magnetically ordered ferric oxides); (4) one region (the Nullarbor) that shows a variation in the total amount of ferric species that closely matches the climatic record for this area of Australia for the last 30 ka. Points (3) and (4) may be related to the identification of a rapid initial weathering phase: the majority of weathering occurs in the first few hundred years after fall, followed by passivation of weathering by porosity reduction. Porosity reduction, and the associated restriction in the ability of water to penetrate the sample, appears to be the mechanism whereby a weathering assemblage formed during the brief initial period of oxidation is preserved through subsequent climatic cycles over the terrestrial lifetime of the sample.

Bland, P. A.; Sexton, A. S.; Jull, A. J. T.; Bevan, A. W. R.; Berry, F. J.; Thornley, D. M.; Astin, T. R.; Britt, D. T.; Pillinger, C. T.

1998-09-01

101

Weathering Experiments  

NSDL National Science Digital Library

This experiment is designed to allow students to observe and understand chemical and physical weathering of simulated "rocks". They will place the materials in plastic bags, one wet and one dry, and store them for 3-4 days. At the end of the storage period, they will observe the contents of both bags and answer some questions about what they see.

102

Space Weathering of Apollo 16 Sample 62255: Lunar Rocks as Witness Plates for Deciphering Regolith Formation Processes  

NASA Technical Reports Server (NTRS)

Space weathering, or alteration that occurs at the surfaces of materials exposed directly to space, has been one of the primary areas of focus of lunar studies for the past several years. It is caused by processes such as micrometeorite impacts and solar wind bombardment, and effects can include microcraters, spall zones, and vapor deposits. Much of the recent work on space weathering has been concentrated on nanoscale features, especially the amorphous rims commonly found on individual lunar soil grains. The rims typically contain nanophase Fe metal globules, which, along with Fe metal globules in agglutinates, have a profound effect on optical properties of lunar soils. The nanophase metallic iron globules cause the characteristic optical changes (reddening and darkening) found in mature lunar soils.

Wentworth, S. J.; McKay, D. S.; Keller, L. P.

2004-01-01

103

The encapsulated GOES-L weather satellite is lifted at the launch pad for mating to an Atlas II rock  

NASA Technical Reports Server (NTRS)

Workers at Launch Pad 36-B, Cape Canaveral Air Station, help guide an encapsulated GOES-L weather satellite up the gantry for mating to a Lockheed Martin Atlas II rocket. The fourth of a new advanced series of geostationary weather satellites for the National Oceanic and Atmospheric Administration (NOAA), GOES-L is a three-axis inertially stabilized spacecraft that will provide pictures and perform atmospheric sounding at the same time. After it is launched, the satellite will undergo checkout and then provide backup capabilities for the existing, aging operational satellites. Once in orbit, the satellite will become GOES-11, joining GOES-8, GOES-9 and GOES-10 in space. The GOES is scheduled for launch later this month.

1999-01-01

104

The encapsulated GOES-L weather satellite is lifted at the launch pad for mating to an Atlas II rock  

NASA Technical Reports Server (NTRS)

After being transported from Astrotech, in Titusville, Fla., the encapsulated GOES-L weather satellite arrives at Launch Pad 36-B, Cape Canaveral Air Station, to be mated to a Lockheed Martin Atlas II rocket. The fourth of a new advanced series of geostationary weather satellites for the National Oceanic and Atmospheric Administration (NOAA), GOES-L is a three-axis inertially stabilized spacecraft that will provide pictures and perform atmospheric sounding at the same time. After it is launched, the satellite will undergo checkout and then provide backup capabilities for the existing, aging operational satellites. Once in orbit, the satellite will become GOES-11, joining GOES-8, GOES-9 and GOES-10 in space. The GOES is scheduled for launch later this month.

1999-01-01

105

The encapsulated GOES-L weather satellite is lifted at the launch pad for mating to an Atlas II rock  

NASA Technical Reports Server (NTRS)

At Launch Pad 36-B, Cape Canaveral Air Station, an encapsulated GOES-L weather satellite is lifted up the gantry for mating to a Lockheed Martin Atlas II rocket. The fourth of a new advanced series of geostationary weather satellites for the National Oceanic and Atmospheric Administration (NOAA), GOES-L is a three- axis inertially stabilized spacecraft that will provide pictures and perform atmospheric sounding at the same time. After it is launched, the satellite will undergo checkout and then provide backup capabilities for the existing, aging operational satellites. Once in orbit, the satellite will become GOES-11, joining GOES-8, GOES-9 and GOES-10 in space. The GOES is scheduled for launch later this month.

1999-01-01

106

Rocks, Rocks, Rocks  

NSDL National Science Digital Library

Students test rocks to identify their physical properties (such as luster, hardness, color, etc.) and classify them as igneous, metamorphic or sedimentary. They complete a worksheet table to record all of the rock properties, and then answer worksheet questions to deepen their understanding of rock properties and relate them to the cavern design problem.

Adventure Engineering

107

Rocks, Rocks, Rocks  

NSDL National Science Digital Library

Continuing the Asteroid Impact challenge, student teams test rocks to identify their physical properties (such as luster, hardness, color, etc.) and classify them as igneous, metamorphic or sedimentary. They complete a worksheet table to record all of the rock properties, and then answer worksheet questions to deepen their understanding of rock properties and relate them to the cavern design problem.

Adventure Engineering

108

Salt Weathering on Mars  

Microsoft Academic Search

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement,

E. Jagoutz

2006-01-01

109

Salt weathering on Mars  

Microsoft Academic Search

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement,

E. Jagoutz

2004-01-01

110

Do Rocks Last Forever?  

NSDL National Science Digital Library

In this activity, students learn about chemical and mechanical weathering in rocks. From the background material, they will learn that the change that takes place in rocks is called weathering and that this term refers to the destructive processes that change the character of rock at or near the Earth's surface. Processes of mechanical weathering (or physical disintegration) break rock into smaller pieces but do not change its chemical composition; processes of chemical weathering (or rock decomposition) transform rocks and minerals exposed to water and atmospheric gases into new chemical compounds (different rocks and minerals), some of which can be dissolved away. Four experiments that illustrate the effects of mechanical and chemical weathering are provided.

111

Salt Weathering on Mars  

NASA Astrophysics Data System (ADS)

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974). However, irrespectively of the climatic environment a liquid brine is a necessity for salt induced fragmentation of rocks.M. C. Malin (1974) JGR Vol 79,26 p 3888-3894

Jagoutz, E.

2006-12-01

112

Vertical anisotropy of hydraulic conductivity in the fissured layer of hard-rock aquifers due to the geological structure of weathering profiles  

E-print Network

to the geological structure of weathering profiles J.C. Maréchala,* , R.Wynsb , P. Lachassagnec , K. Subrahmanyamd observations, the fissured layer of the weathered granite profile showing the existence of many sub to the weathering process over that one of fissures with a tectonic origin. Keywords: weathering, hard

Paris-Sud XI, Université de

113

Testing the limits of micro-scale analyses of Si stable isotopes by femtosecond laser ablation multicollector inductively coupled plasma mass spectrometry with application to rock weathering  

NASA Astrophysics Data System (ADS)

An analytical protocol for accurate in-situ Si stable isotope analysis has been established on a new second-generation custom-built femtosecond laser ablation system. The laser was coupled to a multicollector inductively coupled plasma mass spectrometer (fsLA-MC-ICP-MS). We investigated the influence of laser parameters such as spot size, laser focussing, energy density and repetition rate, and ICP-MS operating conditions such as ICP mass load, spectral and non-spectral matrix effects, signal intensities, and data processing on precision and accuracy of Si isotope ratios. We found that stable and reproducible ICP conditions were obtained by using He as aerosol carrier gas mixed with Ar/H2O before entering the plasma. Precise ?29Si and ?30Si values (better than ± 0.23‰, 2SD) can be obtained if the area ablated is at least 50 × 50 ?m; or, alternatively, for the analysis of geometric features down to the width of the laser spot (about 20 ?m) if an equivalent area is covered. Larger areas can be analysed by rastering the laser beam, whereas small single spot analyses reduce the attainable precision of ?30Si to ca. ± 0.6‰, 2SD, for < 30 ?m diameter spots. It was found that focussing the laser beam beneath the sample surface with energy densities between 1 and 3.8 J/cm2 yields optimal analytical conditions for all materials investigated here. Using pure quartz (NIST 8546 aka. NBS-28) as measurement standard for calibration (standard-sample-bracketing) did result in accurate and precise data of international reference materials and samples covering a wide range in chemical compositions (Si single crystal IRMM-017, basaltic glasses KL2-G, BHVO-2G and BHVO-2, andesitic glass ML3B-G, rhyolitic glass ATHO-G, diopside glass JER, soda-lime glasses NIST SRM 612 and 610, San Carlos olivine). No composition-dependent matrix effect was discernible within uncertainties of the method. The method was applied to investigate the Si isotope signature of rock weathering at the micro-scale in a corestone sampled from a highly weathered roadcut profile in the tropical Highlands of Sri Lanka. The results show that secondary weathering products accumulated in cracks and grain boundaries are isotopically lighter than their unweathered plagioclase host, consistent with isotopically heavy dissolved Si found in rivers.

Schuessler, Jan A.; von Blanckenburg, Friedhelm

2014-08-01

114

Weathering of Minerals  

NSDL National Science Digital Library

Students determine the % change in mass of mineral samples that have been placed in a rock tumbler. They graph the relationship between the hardness of the mineral and the % change in mass. They then consider why some of the mineral samples do not conform the the relationship they graphed. They investigate the physical properties of the outliers and consider how the physical properties contributed to the rate of weathering, and what kind of weathering occured in the rock tumbler.

Van Norden, Wendy

115

Vertical anisotropy of hydraulic conductivity in fissured layer of hard-rock aquifers due to the geological structure of weathering profiles  

E-print Network

to the geological structure of weathering profiles Jean-Christophe Maréchala,* , Robert Wynsb , Patrick Lachassagnec, the fissured layer of the weathered granite profile showing the existence of many sub-horizontal fissures. It confirms that, within the fissured layer, the permeability of sub-horizontal fissures due to the weathering

Paris-Sud XI, Université de

116

Salt weathering on Mars  

NASA Astrophysics Data System (ADS)

Large well rounded boulders and angular rock fragments characterizes the Martian landscape as seen on the recent excellent quality photos. Analyzing the different rock-shapes indicates a time sequence of emplacement, fragmentation and transport of different rocks on Mars, which might give interesting insight into transport and weathering processes. Larger commonly well rounded boulders were emplaced onto gravel plains. After emplacement, these rocks were fragmented and disassembled. Nests of angular rock fragments are marking the locations of preexisting larger rocks. Frequently it is possible to reconstruct larger rounded rocks from smaller angular fragments. In other cases transport after fragmentation obscured the relationship of the fragments. However, a strewn field of fragments is still reminiscent of the preexisting rock. Mechanical salt weathering could be a plausible explanation for the insitu fragmentation of larger rounded blocks into angular fragments. Impact or secondary air fall induced fragmentation produces very different patterns, as observed around impact crates on Earth. Salt weathering of rocks is a common process in terrestrial environments. Salt crystallization in capillaries causes fragmentation of rocks, irrespective of the process of salt transportation and concentration. On Earth significant salt weathering can be observed in different climatic environments: in the transition zone of alluvial aprons and salt playas in desserts and in dry valleys of Antarctica. In terrestrial semi-arid areas the salt is transported by salt solution, which is progressively concentrated by evaporation. In Antarctic dry valleys freeze-thaw cycles causes salt transportation and crystallization resulting in rock fragmentation. This salt induced process can lead to complete destruction of rocks and converts rocks to fine sand. The efficient breakdown of rocks is dominating the landscape in some dry valleys of the Earth but possibly also on Mars. (Malin, 1974). However, irrespectively of the climatic environment a liquid brine is a necessity for salt induced fragmentation of rocks. If salt weathering is responsible for the fragmented rocks on the Martian surface it implies a temporary present of liquid H_2O. However, due to the present dry atmosphere on Mars brines can only be present in restricted places without being in equilibrium with the atmosphere (Clark and van Hart 1980). M. C. Malin (1974) JGR Vol 79,26 p 3888-3894 B. C. Clark and D. C. vanHart (1980) ICARUS 45, 370-378

Jagoutz, E.

117

Bacteria in Weathered Basaltic Glass, Iceland  

Microsoft Academic Search

Bacteria play an important role in rock weathering and yet their diversity and potential activity in the terrestrial rock weathering environment is poorly understood. Culture and culture-independent methods (16S rDNA) were used to investigate the populations of bacteria inhabiting a basaltic glass\\/palagonite subglacial (hyaloclastite) deposit subject to weathering in Iceland. The rock hosts a diverse microbial community. The 16S rDNA

Charles S. Cockell; Karen Olsson; Felicity Knowles; Laura Kelly; Aude Herrera; Thorsteinn Thorsteinsson; Viggo Marteinsson

2009-01-01

118

Honeycomb Weathering of Limestone Formations  

USGS Multimedia Gallery

Honeycomb weathering of sandstone located on the shores of Puget Sound occurs when expanding salt crystals break fragments of rock, creating a small hole that becomes larger as the process repeats itself over time....

2010-08-16

119

Weathering of Stone Mountain Granite  

Microsoft Academic Search

The weathering of Stone Mountain Granite (adamellitc) forms kaolinite, endcllite, allophane and gibbsite of which kaolinite is the most stable. Bulk density ranges from 2.65 in fresh rock to a minimum of 1.48 in saprolite. It is a good index of weathering. Abrasion pH ranges from 5.0 in saprolite to 9.3 in fresh rock, and is direct)y related to bulk

1962-01-01

120

Weather Vane  

NSDL National Science Digital Library

In this meteorology activity, learners build weather vanes using straws, paperclips, and cardstock. Learners will explore wind and air resistance as well as how weather vanes are used to understand and predict weather.

Workshop, Fresno C.

2011-01-01

121

Weather Watch  

ERIC Educational Resources Information Center

Suggests a number of ways in which Federal Aviation Agency weather report printouts can be used in teaching the weather section of meteorology. These weather sequence reports can be obtained free of charge at most major airports. (JR)

Bratt, Herschell Marvin

1973-01-01

122

Weathering and weathering rates of natural stone  

NASA Astrophysics Data System (ADS)

Physical and chemical weathering were studied as separate processes in the past. Recent research, however, shows that most processes are physicochemical in nature. The rates at which calcite and silica weather by dissolution are dependent on the regional and local climatic environment. The weathering of silicate rocks leaves discolored margins and rinds, a function of the rocks' permeability and of the climatic parameters. Salt action, the greatest disruptive factor, is complex and not yet fully understood in all its phases, but some of the causes of disruption are crystallization pressure, hydration pressure, and hygroscopic attraction of excess moisture. The decay of marble is complex, an interaction between disolution, crack-corrosion, and expansion-contraction cycies triggered by the release of residual stresses. Thin spalls of granites commonly found near the street level of buildings are generally caused by a combination of stress relief and salt action. To study and determine weathering rates of a variety of commercial stones, the National Bureau of Standards erected a Stone Exposure Test Wall in 1948. Of the many types of stone represented, only a few fossiliferous limestones permit a valid measurement of surface reduction in a polluted urban environment.

Winkler, Erhard M.

1987-06-01

123

Severe Weather  

ERIC Educational Resources Information Center

Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This month's insert, Severe Weather, has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in this poster are hurricanes,…

Forde, Evan B.

2004-01-01

124

Severe Weather  

ERIC Educational Resources Information Center

Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. This article deals with a poster entitled, "Severe Weather," that has been created by NOAA to help educate the public about hazardous weather conditions. The four types of severe weather highlighted in…

Forde, Evan B.

2004-01-01

125

International Symposium on Hydrogeology and the Environment, Wuhan, China, Oct. 17 20, 2000 A confined groundwater zone in weathered igneous rocks and its impact  

E-print Network

in igneous rock saprolites are a serious natural hazard in Hong Kong and have been extensively studied the saprolite has been treated as an aquifer while the bedrock is considered as an impermeable boundary, with the focus of research on the saprolite above the bedrock. This paper will demonstrate that, at least in some

Jiao, Jiu Jimmy

126

UM Weather  

NSDL National Science Digital Library

Sponsored by The Weather Underground at the University of Michigan at Ann Arbor, UM Weather bills itself as the "Internet's premier source of weather information." The site offers several general audience tools such as the Fast Forecast for any city in the US, ski weather, and weather cams. But, it also provides access to over two dozen weather software packages, a new computer model forecasts page, and most impressively a list of close to 400 other weather related Web sites. Professionals and researchers will appreciate the non-technical feel of the site and the valuable information they can procure from it.

1994-01-01

127

Weathering of phosphorus in black shales  

Microsoft Academic Search

Rock weathering is the ultimate source of phosphorus (P) to the oceans, where P can be a limiting nutrient for biological production. In this paper, P weathering is examined in soil chronosequences formed in weathering profiles on the organic-rich Woodford Shale, New Albany Shale and Green River Shale. At all sites, organic P and inorganic P concentrations reveal that P

Lauren Clark Kolowith; Robert A. Berner

2002-01-01

128

Weather Forecasting  

NSDL National Science Digital Library

This website, supplied by Annenberg / CPB, discusses weather satellites, Doppler radar, and additional tools forecasters use to predict the weather. Students can find a wind chill calculator along with a brief discussion of the history of forecasting and weather lore. Once you have a firm grasp on the science of weather forecasting, be sure to check out the other sections of this site, which include: "ice and snow," "our changing climate," "the water cycle," and "powerful storms."

2008-03-27

129

Antarctic Weather  

NSDL National Science Digital Library

Visitors to this site can read a discussion about the weather in Anarctica, including why it is so cold, how weather observations are conducted there, and what role the continent plays in the global weather system. Links to related topics, a wind chill calculator, and a Fahrenheit-Celsius-Kelvin temperature converter are also provided.

130

Severe Weather  

NSDL National Science Digital Library

Educating the public about safety issues related to severe weather is part of the National Oceanic and Atmospheric Administration's (NOAA) mission. The National Weather Service (NWS)--which is part of NOAA and its parent agency, the Department of Commerce--is charged with the critical responsibility of observing and reporting the weather and with issuing forecasts and warnings of weather and floods in the interest of national safety and economy. Through a massive network of weather-monitoring and reporting stations around the globe, including land, sea, air, and space-borne instruments, NWS scientists constantly assimilate all of the reliable weather data available. Much of this data are then used in numerical computer models of the atmosphere that help to accurately describe and interpret current conditions and produce the best possible forecasts of future weather.

Forde, Evan B.

2004-04-01

131

Predicting Weather  

NSDL National Science Digital Library

By performing the activities presented in this website, fourth grade students can learn about weather instruments and data collection. This website, produced by the Government of Saskatchewan, also explores how the weather can impact local communities. Each activity presented here includes both objectives and assessment techniques for the lesson. Sixteen different activity suggestions provide students and teachers with ample opportunities to explore weather in the classroom.

2008-03-28

132

Weather Experiments  

NSDL National Science Digital Library

Looking for fun ways to learn about weather? Weather Wiz Kids has 39 fun weather related experiments for you to try. These experiments can be done in the classroom with your friends or even at home! Some of the experiments on the site include: tornado in a bottle, make lightning, make it rain, cloud in a bottle, what's in the wind, the Doppler Effect, and baking soda volcano.

2010-01-01

133

Weather Instruments  

NSDL National Science Digital Library

This Topic in Depth discusses the variety of instruments used to collect climate and weather data. The first two websites provide simple introductions to the many weather instruments. Bethune Academy's Weather Center (1) discusses the functions of psychrometers, anemometers, weather balloons, thermometers, and barometers. The Illinois State Water Survey (2) furnishes many images of various instruments that collect data daily for legal issues, farmers, educators, students, and researchers. The third website (3), created by the Center for Improving Engineering and Science Education (CIESE), provides a classroom activity to educate users on how to build and use weather instruments. By the end of the group project, students should know all about wind vanes, rain gauges, anemometers, and thermometers. Next, the Miami Museum of Science provides a variety of activities to help students learn about the many weather instruments including wind scales and wind chimes (4). Students can learn about the wind, air pressure, moisture, and temperature. At the fifth website, the Tyson Research Center at Washington University describes the devices it uses in its research (5). At the various links, users can find out the center's many projects that utilize meteorological data such as acid rain monitoring. The sixth website, a pdf document created by Dr. John Guyton at the Mississippi State University Extension Service, provides guidance to teachers about the education of weather patterns and instruments (6). Users can find helpful information on pressure systems, humidity, cloud patterns, and much more. Next, the University of Richmond discusses the tools meteorologists use to learn about the weather (7). While providing materials about the basic tools discussed in the other websites, this site also offers information about weather satellites, radar, and computer models. After discovering the many weather instruments, users can learn about weather data output and analysis at the Next Generation Weather Lab website (8). This expansive website provides an abundance of surface data and upper air data as well as satellite and radar images for the United States.

134

Rock Cycle: Environments of Formation  

NSDL National Science Digital Library

This Science Object is the second of four Science Objects in the Rocks SciPack. It provides an in-depth exploration of the conditions and environment required during the formation of igneous, sedimentary, and metamorphic rocks. Igneous rock forms from the cooling and crystallization of magma. Sometimes the magma reaches Earth's surface and cools quickly; sometimes it does not reach the surface and thus cools slowly. Rocks at Earth's surface are subjected to processes of weathering and erosion, producing sediments as they are broken down. Sedimentary rock is formed when sediments are buried and solidified through various processes. Sedimentary rock buried deep enough may be transformed into metamorphic rock or melted down to magma. Rock formed deep within the crust (either igneous or metamorphic) may be forced up again to become land surface and even mountains by the forces that drive the motion of Earth's plates. Subsequently, this new rock too will erode. Learning Outcomes:� Realize that different rocks have specific origins, and that they are the product of any number of processes.� Identify the processes through which igneous, sedimentary, and metamorphic rock form.� Explain the role of intermediary materials such as sediment and magma in the formation of different kinds of rock.� Provide an overarching description of the steps in the rock cycle, the formation of sedimentary rock, the re-forming of rock by heat and pressure, and the process by which re-formed rock can return to the surface.

National Science Teachers Association (NSTA)

2006-11-01

135

Weather Forecasting  

NSDL National Science Digital Library

This activity (on page 2 of the PDF) is a full inquiry investigation into meteorology and forecasting. Learners will research weather folklore, specifically looking for old-fashioned ways of predicting the weather. Then, they'll record observations of these predictors along with readings from their own homemade barometer, graphing the correct predictions for analysis. Relates to linked video, DragonflyTV: Forecasting.

Twin Cities Public Television, Inc.

2005-01-01

136

Space Weather  

E-print Network

Space Weather :: Printer Friendly Version of Article 2004SW000119 http://www.agu magnetic Faraday cages, to designing artificial magnetospheres around the spacecraft, to employing into nature. Louis J. Lanzerotti is Editor of Space Weather, Distinguished Research Professor at the New

Shepherd, Simon

137

Wacky Weather  

ERIC Educational Resources Information Center

What do a leaf blower, water hose, fan, and ice cubes have in common? Ask the students who participated in an integrative science, technology, engineering, and mathematics (I-STEM) education unit, "Wacky Weather," and they will tell say "fun and severe weather"--words one might not have expected! The purpose of the unit…

Sabarre, Amy; Gulino, Jacqueline

2013-01-01

138

Making & Breaking: The Rock Cycle  

NSDL National Science Digital Library

Students learn the components of the rock cycle and how rocks can change over time under the influence of weathering, erosion, pressure and heat. They learn about geotechnical engineering and the role these engineers play in the development of an area of land, the design and placement of new structures, and detection of natural disasters.

Integrated Teaching And Learning Program

139

Rock to Regolith Earth's Critical Zone on Volcanic Ocean Islands  

E-print Network

from Anderson et al. (2007) Elements Mobile regolith Weathered rock Unweathered rock #12;Soil mantled Osborn Mt, WY Bedrock-dominated Green Lakes Valley, CO #12;How does rock become soil? Oregon Cascades #12 lens growth #12;Ice lenses in soils Ice lenses in rock Water freezing in soil and rocks Murton et al

Geist, Dennis

140

Role of Microorganisms in Wear Down of Rocks and Minerals  

Microsoft Academic Search

Rock weathering is an awkward term. Near and below the Earth’s surface, physical and chemical processes operate under direct or indirect control of living matter. Weathering, however, strongly relates to physical and chemical changes produced by the weather and its long-term average, the climate. Meteorological connotation of the term ignores the importance of biological interactions in the process of rock

Anna A. Gorbushina; W. E. Krumbein

141

Weather Forecasting  

NSDL National Science Digital Library

Weather Forecasting is a set of computer-based learning modules that teach students about meteorology from the point of view of learning how to forecast the weather. The modules were designed as the primary teaching resource for a seminar course on weather forecasting at the introductory college level (originally METR 151, later ATMO 151) and can also be used in the laboratory component of an introductory atmospheric science course. The modules assume no prior meteorological knowledge. In addition to text and graphics, the modules include interactive questions and answers designed to reinforce student learning. The module topics are: 1. How to Access Weather Data, 2. How to Read Hourly Weather Observations, 3. The National Collegiate Weather Forecasting Contest, 4. Radiation and the Diurnal Heating Cycle, 5. Factors Affecting Temperature: Clouds and Moisture, 6. Factors Affecting Temperature: Wind and Mixing, 7. Air Masses and Fronts, 8. Forces in the Atmosphere, 9. Air Pressure, Temperature, and Height, 10. Winds and Pressure, 11. The Forecasting Process, 12. Sounding Diagrams, 13. Upper Air Maps, 14. Satellite Imagery, 15. Radar Imagery, 16. Numerical Weather Prediction, 17. NWS Forecast Models, 18. Sources of Model Error, 19. Sea Breezes, Land Breezes, and Coastal Fronts, 20. Soundings, Clouds, and Convection, 21. Snow Forecasting.

Nielsen-Gammon, John

1996-09-01

142

4, 555588, 2007 Weathering rates and  

E-print Network

deposits and thus decreasing soil/water contact resulting in lower weathering rates. Furthermore in sub arctic boreal climates is controlled by the residence time for soil water rock interactions significantly decreases alkalinity export20 to the sea because lower weathering rates gives less carbon dioxide

Paris-Sud XI, Université de

143

Planetary Weather  

NSDL National Science Digital Library

This lesson plan is part of the DiscoverySchool.com lesson plan library for grades 6-8. It focuses on the weather conditions on other planets. After learning more about weather patterns, students research the weather on a given planet and create a visual display of the conditions there. It includes objectives, materials, procedures, discussion questions, evaluation ideas, suggested readings, and vocabulary. There are videos available to order which complement this lesson, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.

144

Rad Rocks  

NSDL National Science Digital Library

Why do we have rocks? How are rocks formed? Why do we have rock cycles? There are all differnt kinds of rocks. What parts make up rocks? Can you sort rocks based on color, hardness, texture, layering, and particle size? How do the things rocks are made of determine how people use them? Organize rocks by color, weight, shape, and sizes. Click here to find out the basics about ...

2010-04-26

145

Weatherizing America  

ScienceCinema

As Recovery Act money arrives to expand home weatherization programs across the country, Zachary Stewart of Phoenix, Ariz., and others have found an exciting opportunity not only to start working again, but also to find a calling.

Stewart, Zachary; Bergeron, T.J.; Barth, Dale; Qualis, Xavier; Sewall, Travis; Fransen, Richard; Gill, Tony;

2013-05-29

146

Weather One  

NSDL National Science Digital Library

This website contains summaries and lessons about various aspects of weather. This includes the seasons, types of clouds, air, winds, global warming, hurricanes, tornadoes and lightning. Worksheets are provided to accompany the lesson themes.

Friend, Duane

147

Winter Weather  

MedlinePLUS

... During a Wildfire Responders Wildfire Smoke After a Fire Worker Safety During Fire Cleanup Wildfires PSAs Related Links Winter Weather Extreme ... at Disaster Sites Preventing Chain Saw Injuries During Tree Removal Electrical Safety and Generators Handling Human Remains ...

148

Weather Creator  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Form groups of three. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What can you do to make it rain or even snow? 4. Does it always snow when ...

Kshumway

2009-09-28

149

Exploring Weather  

NSDL National Science Digital Library

Second Grade Standard 3: Students will develop an understanding of their environment. Objective 2: Observe and describe weather. Indicator a: Observe and describe patterns of change in weather. Monday, February 1st: Look at the five-day forecast for Salt Lake City, Utah at Five day forecasts. The high temperature for the day will be in red and the low temperature will be in blue. Make sure you look at the temperature listed in degrees Farenheit (F) not degrees Celcius (C). Make ...

Emily, Miss

2010-01-29

150

Weather Maps  

NSDL National Science Digital Library

This lesson plan is part of the DiscoverySchool.com lesson plan library for grades K-5. It focuses on basic information about the weather and how different weather maps depict conditions. Included are objectives, materials, procedures, discussion questions, evaluation ideas, suggested readings, and vocabulary. There are videos available to order which complement this lesson, and links to teaching tools for making custom quizzes, worksheets, puzzles and lesson plans.

151

Where fast weathering creates thin regolith and slow weathering creates thick regolith  

SciTech Connect

Weathering disaggregates rock into regolith the fractured or granular earthmaterial that sustains life on the continental land surface. Here, we investigate what controls the depth of regolith formed on ridges of two rock compositions with similar initial porosities in Virginia (USA).A priori, we predicted that the regolith on diabasewould be thicker than on granite because the dominant mineral (feldspar) in the diabase weathers faster than its granitic counterpart. However, weathering advanced 20deeper into the granite than the diabase. The 20-thicker regolith is attributed mainly to connected micron-sized pores, microfractures formed around oxidizing biotite at 20m depth, and the lower iron (Fe) content in the felsic rock. Such porosity allows pervasive advection and deep oxidation in the granite. These observations may explainwhy regolithworldwide is thicker on felsic compared tomafic rock under similar conditions. To understand regolith formationwill require better understanding of such deep oxidation reactions and how they impact fluid flow during weathering.

Bazilevskaya, Ekaterina [Pennsylvania State University, University Park, PA; Lebedeva, Marina [Pennsylvania State University, University Park, PA; Pavich, Milan [U.S. Geological Survey, Reston, VA; Rother, Gernot [ORNL; Parkinson, D. Y. [Advanced Light Source, LBNL; Cole, David [Ohio State University; Brantley, S. L. [Pennsylvania State University, University Park, PA

2012-01-01

152

Rock Hounds  

NSDL National Science Digital Library

The Rock Hounds web site offers information for younger students on how igneous, sedimentary, and metamorphic rocks are formed, safety tips for collectors, and illustrated pages describing a selection of rock types. After studying these pages, kids can take a quiz or work rock-themed puzzles. For teachers, there is a lesson plan about the rock cycle, a set of activities, ideas for collaborative activities, and a review of some literature on rocks and rock collecting.

153

Weather Forecasting  

NSDL National Science Digital Library

Weather Forecasting is one of several online guides produced by the Weather World 2010 project at the University of Illinois. These guides use multimedia technology and the dynamic capabilities of the web to incorporate text, colorful diagrams, animations, computer simulations, audio, and video to introduce topics and concepts in the atmospheric sciences. This module introduces forecast methods and the numerous factors one must consider when attempting to make an accurate forecast. Sections include forecasting methods for different scenarios, surface features affecting forecasting, forecasting temperatures for day and night, and factors for forecasting precipitation.

2010-01-01

154

Wild Weather  

NSDL National Science Digital Library

In this online, interactive module, students learn about severe weather (thunderstorms, hurricanes, tornadoes, and blizzards) and the key features for each type of "wild weather" using satellite images. The module is part of an online course for grades 7-12 in satellite meteorology, which includes 10 interactive modules. The site also includes lesson plans developed by teachers and links to related resources. Each module is designed to serve as a stand-alone lesson, however, a sequential approach is recommended. Designed to challenge students through the end of 12th grade, middle school teachers and students may choose to skim or skip a few sections.

155

Wonderful Weather  

NSDL National Science Digital Library

Second Grade Standard 3: Students will develop an understanding of their environment. Objective 2: Observe and describe weather. Indicator a: Observe and describe patterns of change in weather. Monday November 6th: Look at the five-day forecast for Logan Utah at Five Day Forecast in Utah. The high temperature for the day will be in red and the low temperature will be in blue. Look at the temperature listed in degrees Farenheit (F) not degrees Celcius (C). Make a bar graph for the ...

Broadhead, Ms.

2007-11-06

156

Space Weather  

NSDL National Science Digital Library

With three levels to choose from on each page - beginner, intermediate or advanced - this site provides information on Space Weather and the terms scientists use to describe the everchanging conditions in space. Explosions on the Sun create storms of radiation, fluctuating magnetic fields, and swarms of energetic particles. These phenomena travel outward through the Solar System with the solar wind. Upon arrival at Earth, they interact in complex ways with Earth's magnetic field, creating Earth's radiation belts and the Aurora. Some space weather storms can damage satellites, disable electric power grids, and disrupt cell phone communications systems. This site provides images, activities, and interesting facts about all of these events.

2004-02-06

157

Unisys Weather  

NSDL National Science Digital Library

The Unisys weather website offers a host of weather analyses and forecasts. In the Analyses link, visitors can find satellite images as well as surface, upper air, and radar images. Visitors can learn the intricacies of Unisys's many forecast models such as the Nested Grid Model (NGM), Aviation Model, and the Rapid Update Cycle (RUC) Model. Users can find archived hurricane data for the Atlantic, the Eastern Pacific, and the Western Pacific. The site also furnishes archived surface maps, infrared satellite images, upper air charts, and sea surface temperature (SST) plots.

158

Riverbank rock identification  

NSDL National Science Digital Library

This exercise is part of a field trip lab in which we see map different till deposits. At a small, meandering sand-bed river in Minnesota, students are directed to wander along the riverbank and pick up gravel-sized rocks. When they each have a handful, I lay a table-sized, laminated map of Minnesota bedrock geology on the ground. I ask the students to identify their rocks, then find the corresponding bedrock units on the map and throw their rocks down in those regions. Soon we have a pile of rocks in northwestern Minnesota into Canada (weathered shales, weathered limestones), northern and northeastern Minnesota (granites, gneisses, basalts and rhyolites if we are lucky) and central Minnesota (dolomite, sandstones, granites). This visually demonstrates that glaciers transported stones from many distant locations and brought them here to southern Minnesota. In addition, we talk about how the river is down-cutting through consecutive layers of till and mixing those particles together in the stream deposits. The exercise gives students practice in identifying rocks, reading maps, and synthesizing different fields of geology to answer a geomorphic question about glacial transport. Designed for a geomorphology course Has minimal/no quantitative component

Triplett, Laura

159

Rock Cycle  

NSDL National Science Digital Library

This interactive Flash animation about the rock cycle is suitable for a review or overview in an introductory level Physical Geology class. It includes animations, photos, and descriptions involving rock types and processes in the rock cycle.

Smoothstone; Company, Houghton M.

160

Rock Cycle  

NSDL National Science Digital Library

This site, from Moorland School in England, describes the rock cycle. Topics briefly discussed include rock formation, erosion, transportation, and deposition, plus various types of rocks. The page is directed towards a middle-school audience.

School, Moorland

161

Weather control  

Microsoft Academic Search

Weather modification, the intentional altering of atmospheric conditions to suit the purposes of humankind, has five basic forms: (1) fog dissipation; (2) rain and snow enhancement; (3) hail suppression; (4) lightning suppression; and (5) the abatement of severe storms such as hurricanes and tornadoes. The dissipation of fog and the seeding of clouds with dry ice or silver iodide to

Leepson

1980-01-01

162

Wonderful Weather  

NSDL National Science Digital Library

In this activity, learners conduct three experiments to examine temperature, the different stages of the water cycle, and how convection creates wind. These activities can be used individually or as a group for a lesson on weather. Note: boiling water is required for this activity; adult supervision required.

Workshop, Mission S.

2013-01-01

163

Weather Stations  

NSDL National Science Digital Library

This is a series of seven brief activities about Jupiter's atmosphere and weather. Learners will look at Jupiter's distinct banded appearance, violent storms, and clouds of many different colors. The activities are part of Explore! Jupiter's Family Secrets, a series designed to engage children in space and planetary science in libraries and informal learning environments.

164

The Weather Doctor  

NSDL National Science Digital Library

Published by Spectrum Educational Enterprises, The Weather Doctor Web site is maintained by meteorologist Keith Heidorn. Visitors to the site will find everything from the joys of weather watching, to making rain, to weather history, to much more. Coming from someone who clearly enjoys what they do, this site explores unique aspects of weather including weather people, weather history, and weather and arts.

Heidorn, Keith.

2002-01-01

165

Engineering Geology of Rock Slopes in Highway Construction  

Microsoft Academic Search

Rock slopes form part of the components in many highway or roadway constructions in hilly terrain. The key question with regard to rock slopes along highways is their long-term stability since failure of a rock slope can have serious consequences. The stability of a particular rock slope is governed by three main engineering geologic factors, namely: lithology, structure and weathering

B. K. Tan

166

Tacoma Power Weatherization  

E-print Network

Tacoma Power Weatherization Specifications August 2009 KnowYourPower.com | #12;TACOMA POWER WEATHERIZATION SPECIFICATIONS 2009 edition Page 2 #12;TACOMA POWER WEATHERIZATION SPECIFICATIONS 2009 edition

167

Estimating rock compressive strength from Rock Abrasion Tool (RAT) grinds  

NASA Astrophysics Data System (ADS)

Each Mars Exploration Rover carries a Rock Abrasion Tool (RAT) whose intended use was to abrade the outer surfaces of rocks to expose more pristine material. Motor currents drawn by the RAT motors are related to the strength and hardness of rock surfaces undergoing abrasion, and these data can be used to infer more about a target rock's physical properties. However, no calibration of the RAT exists. Here, we attempt to derive an empirical correlation using an assemblage of terrestrial rocks and apply this correlation to data returned by the rover Spirit. The results demonstrate a positive correlation between rock strength and RAT grind energy for rocks with compressive strengths less than about 150 MPa, a category that includes all but the strongest intact rocks. Applying this correlation to rocks abraded by Spirit's RAT, the results indicate a large divide in strength between more competent basaltic rocks encountered in the plains of Gusev crater (Adirondack-class rocks) and the weaker variety of rock types measured in the Columbia Hills. Adirondack-class rocks have estimated compressive strengths in the range of 70-130 MPa and are significantly less strong than fresh terrestrial basalts; this may be indicative of a degree of weathering-induced weakening. Rock types in the Columbia Hills (Wishstone, Watchtower, Clovis, and Peace class) all have compressive strengths <50 MPa and are consistent with impactites or volcanoclastic materials. In general, when considered alongside chemical, spectral, and rock textural data, these inferred compressive strength results help inform our understanding of rock origins and modification history.

Thomson, B. J.; Bridges, N. T.; Cohen, J.; Hurowitz, J. A.; Lennon, A.; Paulsen, G.; Zacny, K.

2013-06-01

168

Rock, Paper, Scissors Probability!  

NSDL National Science Digital Library

Students learn about probability through a LEGO® MINDSTORMS® NTX-based activity that simulates a game of "rock-paper-scissors." The LEGO robot mimics the outcome of random game scenarios in order to help students gain a better understanding of events that follow real-life random phenomenon, such as bridge failures, weather forecasts and automobile accidents. Students learn to connect keywords such as certainty, probable, unlikely and impossibility to real-world engineering applications.

AMPS GK-12 Program,

169

Weather Cycles  

NSDL National Science Digital Library

We are professionals in the teaching profession. We designed this project for children ranging from 4th grade to 6th grade. This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. YOU WILL NEED: Paper with copied questions, Overhead projector and Students broken up into groups of 3. Form groups of three. Have each group explore the following simulation: Weather Maker Simulator Have students use the simulation to answer the following questions on paper. They should be discussing the questions in their groups. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What ...

Mitchell, Mrs.

2010-09-23

170

Weather control  

SciTech Connect

Weather modification, the intentional altering of atmospheric conditions to suit the purposes of humankind, has five basic forms: (1) fog dissipation; (2) rain and snow enhancement; (3) hail suppression; (4) lightning suppression; and (5) the abatement of severe storms such as hurricanes and tornadoes. The dissipation of fog and the seeding of clouds with dry ice or silver iodide to produce rain are the most successful weather modification techniques. Both are used extensively and with varying degrees of success in the United States and around the world. Cloud seeding, though, is not effective in easing the harshness of a drought, such as the one that hit the Southwest, Midwest and Great Plains this summer.

Leepson, M.

1980-09-05

171

Weather Watchers  

NSDL National Science Digital Library

Students are introduced to some essential meteorology concepts so they more fully understand the impact of meteorological activity on air pollution control and prevention. First, they develop an understanding of the magnitude and importance of air pressure. Next, they build a simple aneroid barometer to understand how air pressure information is related to weather prediction. Then, students explore the concept of relative humidity and its connection to weather prediction. Finally, students learn about air convection currents and temperature inversions. In an associated literacy activity, students learn how scientific terms are formed using Latin and Greek roots, prefixes and suffixes, and are introduced to the role played by metaphor in language development. Note: Some of these activities can be conducted simultaneously with the air quality activity (What Color Is Your Air Today?) of Air Pollution unit, Lesson 1.

Integrated Teaching And Learning Program

172

Desert Rock Coatings Ronald I. Dorn  

E-print Network

State University, Tempe, AZ 85287, USA e-mail: ronald.dorn@asu.edu as well as application of artificial, and sulfate crusts. In another example, lithobionts like lichens are normally associated with rock weathering

Dorn, Ron

173

Igneous Rocks  

NSDL National Science Digital Library

This interactive lesson on igneous rocks begins with a comparison of intrusive and extrusive igneous rocks with diagrams to show their origin. This leads to a discussion of intrusive rock formations including dikes, sills, laccoliths and batholiths and a block diagram to show their location. Basaltic rocks are described to include basalt, pumice, and gabbro and are contrasted with granitic rhyolite and obsidian.

174

Multimedia Rocks  

NSDL National Science Digital Library

As part of a unit on rocks and minerals, students engaged in hands-on, inquiry-based activities that helped them discover what geologists do, how to identify rocks and minerals, and how rocks change over time through the rock cycle. This article describes

Perry, Laurie

2000-05-01

175

National Weather Service  

MedlinePLUS

HOME FORECAST Local Graphical Aviation Marine Rivers and Lakes Hurricanes Severe Weather Fire Weather Sun/Moon Long Range Forecasts Climate Prediction PAST WEATHER Past Weather Heating/Cooling Days Monthly ...

176

rock properties  

NSDL National Science Digital Library

Rocks are the most common material on earth. We will learn about the parts that make up the rocks and sort rocks based upon color, hardness, texture, layering, and particle size. Lets review: What do you already know about rocks? Please write down your thoughts on a piece of paper. Now, click on the link below to find out what the definition of a rock is. *Intro to Rocks Please answer the questions below in complete sentences on your paper. 1. Rocks are made up of several particles. ...

Krystal

2009-12-14

177

Investigaing Rocks  

NSDL National Science Digital Library

Your mission is to look at different types of rocks and be able to sort them based on color, feel, hardness, texture, layering they may have, and particle size they are made of. Identify how the properties of rocks determine how people use them. Click below to find out more about different kinds of rocks there are: Types of Rocks Now, Start Your Rock Collection! It's a race against time! Can you do it? Identify Rock Types How are rocks made? Check out: The Rock Cycle Now take the quiz: Diagram the rock cycle quiz Next, click the link to view the Virtual Quarry website. Here, you will be able to look at different rock ...

Lindsey, Tiffany A.

2010-06-21

178

Weathering: methods and techniques to measure  

NASA Astrophysics Data System (ADS)

Surface recession takes place when weathered material is removed from the rocks. In order to know how fast does weathering and erosion occur, a review of several methods, analyses and destructive and non-destructive techniques to measure weathering of rocks caused by physico-chemical changes that occur in bedrocks due to salt crystallization, freezing-thaw, thermal shock, influence of water, wind, temperature or any type of environmental agent leading to weathering processes and development of soils, in-situ in the field or through experimental works in the laboratory are addressed. From micro-scale to macro-scale, from the surface down to more in depth, several case studies on in-situ monitoring of quantification of decay on soils and rocks from natural landscapes (mountains, cliffs, caves, etc) or from urban environment (foundations or facades of buildings, retaining walls, etc) or laboratory experimental works, such as artificial accelerated ageing tests (a.a.e.e.) or durability tests -in which one or more than one weathering agents are selected to assess the material behaviour in time and in a cyclic way- performed on specimens of these materials are summarised. Discoloration, structural alteration, precipitation of weathering products (mass transfer), and surface recession (mass loss) are all products of weathering processes. Destructive (SEM-EDX, optical microscopy, mercury intrusion porosimetry, drilling resistance measurement, flexural and compression strength) and Non-destructive (spectrophotocolorimetry, 3D optical surface roughness, Schmidt hammer rebound tester, ultrasound velocity propagation, Nuclear Magnetic Resonance NMR, X ray computed micro-tomography or CT-scan, geo-radar differential global positioning systems) techniques and characterization analyses (e.g. water absorption, permeability, open porosity or porosity accessible to water) to assess their morphological, physico-chemical, mechanical and hydric weathering; consolidation products or methods to stop or to slow down their weathering or durability and stability of soils and rocks are also topics where the methods and techniques deal with the quantification of weathering. Cultural stone weathering studies contribute substantially to the knowledge of weathering rates revealing the importance of specific weathering agents and weathering factors.

Lopez-Arce, P.; Zornoza-Indart, A.; Alvarez de Buergo, M.; Fort, R.

2012-04-01

179

Chemical Weathering of Black Shales and Rare Earth Element Composition of Surface Waters and Groundwater  

Microsoft Academic Search

Weathering processes dominate the dissolved and suspended loads of most of the world's major rivers. Among sedimentary rocks, black shales are particularly sensitive to chemical weathering. Therefore, shale systems are useful for investigating the partitioning of chemical elements during chemical weathering. Recent studies, such as those by Peucker-Ehrenbrink, Ravizza and others, link chemical weathering of black shales to changes in

R. E. Hannigan; K. H. Johannesson

2001-01-01

180

Metamorphic Rocks  

NSDL National Science Digital Library

This interactive lesson on metamorphic rocks starts with a review of the rock cycle and goes on to describe the relationship between metamorphic rocks and their parent rock. The lesson then describes the agents of metamorphism (temperature, pressure, and chemical change) and moves into a discussion on contact, regional, and dynamic metamorphism. The remainder of the lesson consists of descriptions of foliated rocks such as slate, schist, and gneiss, and the non-foliates exemplified by quartzite and white marble.

181

Weather Forecasting for Weather Derivatives  

Microsoft Academic Search

Abstract: We take a nonstructural time-series approach to modeling and forecasting daily average temperature in ten U.S. cities, and we inquire systematically as to whether it may prove useful from the vantage point of participants in the weather derivatives market. The answer is, perhaps surprisingly, yes. Time series modeling reveals both strong conditional mean dynamics,and conditional variance dynamics in daily

Sean D. Campbell; Francis X. Diebold

2005-01-01

182

Mountain Weather  

NSDL National Science Digital Library

Mountains can be awe-inspiring both for the vistas they provide and for the weather events and long-term climate systems they support. This interactive feature illustrates how a moisture-laden air mass interacts with a mountain slope to produce characteristic patterns of precipitation over the mountain and surrounding areas. Viewers can see how clouds and precipitation form as the air mass ascends the windward side of the peak, and observe the rain shadow created on the leeward side by the descending, warmed, and moisture-depleted air. A background essay and list of discussion questions supplement the interactive feature.

183

Observe the effects of mechanical weathering  

NSDL National Science Digital Library

In this interactive Earth science resource, students are first presented with six photographs, each featuring a different mechanical weathering event in which rock is broken down. Examples of the events include road damage due to ice heaving and the expansion of cracks in rocks due to tree growth. Students are instructed to click on each labeled image to see an enlarged version of it. In the enlarged view, brief text, often accompanied by visual cues such as arrows, explains the physical weathering process shown. Copyright 2005 Eisenhower National Clearinghouse

Education, Terc. C.; Littell, Mcdougal

2003-01-01

184

Rock Identification  

NSDL National Science Digital Library

This hands-on activity covers the basics of rock identification. After a brief discussion of the terms 'rock' and 'mineral', students will study the characteristics and classifications of the three major rock groups (igneous, metamorphic, and sedimentary). Using an online tutorial to test their knowledge and to learn more about rocks, they will identify 10 different specimens, record their observations, and provide a name for each.

Pratte, John

185

Metamorphic Rocks  

NSDL National Science Digital Library

Here is an in-depth description of metamorphic rocks, from their classification to formation and identification. It covers types of metamorphism (including Barrovian, or regional rock changes), classification by foliation, and metamorphic processes (facies and zones). An alphabetical list of rocks with picture, composition, description, tectonic association, and type of metamorphism is given. Common metamorphic minerals are covered as well.

Fichter, Lynn

186

Rock Jeopardy!  

NSDL National Science Digital Library

Students reinforce their understanding of rocks, the rock cycle, and geotechnical engineering by playing a trivia game. They work in groups to prepare Jeopardy-type trivia questions (answers) and compete against each other to demonstrate their knowledge of rocks and engineering.

Integrated Teaching And Learning Program

187

Annual fossil organic carbon delivery due to mechanical and chemical weathering of marly badlands areas  

E-print Network

are composed of a combination of various sedimentary, metamorphic and plutonic rocks. Sedimentary rocks Carbon (FOC) release by weathering of outcropping sedimentary rocks on continental surfaces is still and Landforms 37 (2012) 1263-1271" DOI : 10.1002/esp.3232 #12;2 particles are characterized by Rock-Eval 6

Paris-Sud XI, Université de

188

The Weather Dude  

NSDL National Science Digital Library

The Weather Dude is a weather education Web site offered by meteorologist Nick Walker of The Weather Channel. For kids, the site offers a great online textbook entitled Weather Basics, which explains everything from precipitation to the seasons, using simple text and fun graphics. Other fun things for kids include weather songs, questions and quizzes, weather proverbs, and more. Teachers are also provided with helpful resources such as weather activity sheets and printable blank maps, as well as many other links to weather forecasts and information that will help make teaching about weather fun.

Walker, Nick.

2002-01-01

189

Investigating Factors that Influence Weathering of Monuments in a Cemetery  

NSDL National Science Digital Library

In this field activity students will discover some of the factors that influence weathering of rock by making observations, asking questions and completing an investigation of their own design in a local cemetery.

190

Weathering of Stone Monuments in Cities: A Student Exercise.  

ERIC Educational Resources Information Center

Describes a college-level geography project for students limited to urban areas. Students investigate the rock-weathering process through library resources, then observe, collect, and analyze data about stone monuments. An individually written report concludes the project. (KC)

Dragovich, D.

1980-01-01

191

Geology of the Oceanic Crust: Magnetic Properties of Oceanic Rocks  

Microsoft Academic Search

A diverse suite of rocks has been sampled from ocean basin escarpments in the North Atlantic and the Caribbean: fresh and weathered basalts, metabasalts (zeolite and greenschist facies), gabbros, met, agabbros (greenschist and amphiolite facies), serpentinized peridotites, and actinolite rocks. One hundred and three representative specimens were chosen from this diverse suite of rocks, and the natural remanent magnetization (NRM)

Paul J. Fox; Neil D. Opdyke

1973-01-01

192

'Escher' Rock  

NASA Technical Reports Server (NTRS)

[figure removed for brevity, see original site] Chemical Changes in 'Endurance' Rocks

[figure removed for brevity, see original site] Figure 1

This false-color image taken by NASA's Mars Exploration Rover Opportunity shows a rock dubbed 'Escher' on the southwestern slopes of 'Endurance Crater.' Scientists believe the rock's fractures, which divide the surface into polygons, may have been formed by one of several processes. They may have been caused by the impact that created Endurance Crater, or they might have arisen when water leftover from the rock's formation dried up. A third possibility is that much later, after the rock was formed, and after the crater was created, the rock became wet once again, then dried up and developed cracks. Opportunity has spent the last 14 sols investigating Escher, specifically the target dubbed 'Kirchner,' and other similar rocks with its scientific instruments. This image was taken on sol 208 (Aug. 24, 2004) by the rover's panoramic camera, using the 750-, 530- and 430-nanometer filters.

The graph above shows that rocks located deeper into 'Endurance Crater' are chemically altered to a greater degree than rocks located higher up. This chemical alteration is believed to result from exposure to water.

Specifically, the graph compares ratios of chemicals between the deep rock dubbed 'Escher,' and the more shallow rock called 'Virginia,' before (red and blue lines) and after (green line) the Mars Exploration Rover Opportunity drilled into the rocks. As the red and blue lines indicate, Escher's levels of chlorine relative to Virginia's went up, and sulfur down, before the rover dug a hole into the rocks. This implies that the surface of Escher has been chemically altered to a greater extent than the surface of Virginia. Scientists are still investigating the role water played in influencing this trend.

These data were taken by the rover's alpha particle X-ray spectrometer.

2004-01-01

193

Effects of climate on chemical_ weathering in watersheds  

Microsoft Academic Search

Climatic effects on chemical weathering are evaluated by correlating variations On solute concentrations and fluxes with temperature, precipitation, runoff, and evapotranspiration (ET) for a worldwide distribution of sixty-eight watersheds underlain by granitoid rock types. Stream solute concentrations are strongly correlated with proportional ET loss, and evaporative concentration makes stream solute concentrations an inappropriate surrogate for chemical weathering. Chemical fluxes are

Art F. White; Alex E. Blum

1995-01-01

194

Science Rocks!  

ERIC Educational Resources Information Center

It all began one Monday morning. Raymond could not wait to come to large group. In his hand, he held a chunk of white granite he had found. "Look at my beautiful rock!" he cried. The rock was passed around and examined by each student. "I wonder how rocks are made?" wondered one student. "Where do they come from?" asked another. At this moment, a…

Prestwich, Dorothy; Sumrall, Joseph; Chessin, Debby A.

2010-01-01

195

Sedimentary Rocks  

NSDL National Science Digital Library

This in-depth description of sedimentary rocks covers their classification as clastic, carbonate, or chemical/biochemical as well as their depositional environments, known as long and short clastic systems and carbonate depositional environments. It also presents a discussion of sedimentary rock evolution with an evolutionary diagram and a section on tectonics and sedimentary rocks. An alphabetical list of rocks with photograph, quartz-feldspar-lithic (QFL) composition, description, tectonic association, and formation and environments is given. Identification keys, both basic and QFL are also provided.

Fichter, Lynn

196

Rock flows  

NASA Technical Reports Server (NTRS)

Rock flows are defined as forms of spontaneous mass movements, commonly found in mountainous countries, which have been studied very little. The article considers formations known as rock rivers, rock flows, boulder flows, boulder stria, gravel flows, rock seas, and rubble seas. It describes their genesis as seen from their morphological characteristics and presents a classification of these forms. This classification is based on the difference in the genesis of the rubbly matter and characterizes these forms of mass movement according to their source, drainage, and deposit areas.

Matveyev, S. N.

1986-01-01

197

Landslide types and their relationships with weathering in a Calabrian basin, southern Italy  

Microsoft Academic Search

The basin of the Alaco River, in the Serre Massif of Calabria (Italy), is characterized by outcropping Palaeozoic granitoid rocks. The complex neotectonic history of the area and adverse climatic conditions, both active at least since the Quaternary, resulted in deep weathering of the crystalline rocks. Field observations, integrated with laboratory and in situ tests, allowed the weathering profile to

Domenico Calcaterra; Mario Parise

2005-01-01

198

Role of fine roots in the plant-induced weathering of andesite for several plant species  

Microsoft Academic Search

The present work aims at providing experimental evidence for weathering as a direct consequence of plant physiology, and the importance of the proximity of fine roots to rock in the weathering process. Discussion is based on the release of different elements from andesite rock particles by the three crop species: rice, maize, and soybean. We designed two types of hydroponic

AKTER MEHERUNA; TASUKU AKAGI

2006-01-01

199

Deep weathering, vegetation and fireburn Significant obstacles for geoscience remote sensing in Australia  

Microsoft Academic Search

Large areas of the land surface of Australia retain effects of prior weathering events, to tens or hundreds of metres depth, which altered previously-exposed rocks to clays and reconcentrated various minerals such as iron oxides, carbonates and silica. In such areas data about surface mineralogy obtained by remote sensing may not relate to rocks at depth beneath the weathered zone.

C. J. SIMPSON

1990-01-01

200

Radiogenic and stable isotope variations accompanying continental weathering  

NASA Astrophysics Data System (ADS)

Many natural isotope systems, both stable and radiogenic, are sensitive to variations in weathering processes, but the difficulty remains in distinguishing variations that result from weathering from those caused by differences in rock type. One approach that circumvents this problem is the study of monolithologic catchments, where variations in physical and chemical weathering rates, runoff, catchment age, vegetative and glacial cover can be related to river chemistry. This study presents an overview of our recent work on radiogenic and stable isotopes in rivers and estuaries from Iceland, draining basaltic terrains, where variations in glacial cover result in a wide range of weathering conditions. Each radiogenic and stable isotope system reveals complementary information on the nature of the weathering process, and the estuarine data indicates how this signal is transferred to the oceans. For the dissolved riverine phase, in the absence of variations in rock type, the principal controls on isotope variations accompanying weathering are; (i) For many radiogenic isotope systems, preferential (incongruent) weathering of specific mineral phases, where those phases possess a markedly different parent/daughter ratio, and hence radiogenic isotope composition; (ii) For many stable isotope systems, preferential removal of an isotope into secondary phases formed during weathering, leaves residual waters depleted in that isotope. Despite the wide range of isotope compositions in the dissolved load, for Iceland it is the nature of weathering of the suspended load in the estuarine environment that likely dominates the signal to the oceans. Moreover, both the flux and nature of the suspended load are highly dependent on riverine discharge, and hence climate change. These results clearly demonstrate that weathering processes can exert a significant influence on the riverine isotope signal to the oceans, and for some isotopes marine sedimentary archives will preserve a record of changes in weathering in response to climatic or tectonic change. The challenge remains in deconvolving the effects of weathering from those caused by variations in rock type, or a simple change in the weathering flux.

Burton, K. W.; Gannoun, A.; Georg, B.; Gislason, S. R.; James, R. H.; Parkinson, I. J.; Pogge von Strandmann, P. A.; Mokadem, F.

2007-12-01

201

Future Weather Station  

NSDL National Science Digital Library

In this activity students build dioramas of futuristic weather stations to demonstrate their knowledge of weather forecasting. They will work in groups to research modern forecasting equipment and techniques, and then build a weather station that will do something we cannot do at present (such as stopping tornadoes). They will present their dioramas and then discuss the pros and cons of controlling the weather.

202

Corridor Integrated Weather System  

Microsoft Academic Search

n Flight delays are now a major problem in the U.S. National Airspace System. A significant fraction of these delays are caused by reductions in en route capacity due to severe convective weather. The Corridor Integrated Weather System (CIWS) is a fully automated weather analysis and forecasting system designed to support the development and execution of convective weather impact mitigation

James E. Evans; Elizabeth R. Ducot

2006-01-01

203

Weather in Your Life.  

ERIC Educational Resources Information Center

Facts and activities related to weather and meteorology are presented in this unit. Separate sections cover the following topics: (1) the water cycle; (2) clouds; (3) the Beaufort Scale for rating the speed and force of wind; (4) the barometer; (5) weather prediction; (6) fall weather in Iowa (sleet, frost, and fog); (7) winter weather in Iowa…

Kannegieter, Sandy; Wirkler, Linda

204

Sedimentary Rocks  

NSDL National Science Digital Library

This overview of sedimentary rocks is part of an online historical geology class taught by Dr. Pamela J.W. Gore at Georgia Perimeter College. The outline format includes basic information about the different types and classifications of sedimentary rocks and their defining characteristics, sedimentary structures, and sedimentary environments. Photographs help illustrate the concepts by providing real-world examples.

Gore, Pamela J.; College, Georgia P.

205

Dynamic tensile strength of lunar rock types  

NASA Technical Reports Server (NTRS)

The dynamic tensile strength of four rocks are determined. A flat plate impact experiment is employed to generate approximately one-microsecond-duration tensile stress pulses in rock samples by superposing rarefaction waves to induce fracture. It is noted that the effect of chemical weathering and other factors has not been explicitly studied. The given tensile strengths are based on a series of experiments on each rock where determination of incipient spallation is made by terminal microscopic examination. The data are generally consistent with previous determinations, at least one of which was for a significantly chemically altered but physically coherent rock.

Cohn, S. N.; Ahrens, T. J.

1981-01-01

206

Relationship between mineral weathering and groundwater composition  

NSDL National Science Digital Library

In this pair of activities, students start by using published data to predict what will happen to groundwater composition as a consequence of chemical weathering. The data are provided in a spreadsheet (Hinman_weathering). Students are given the histograms only; both are normalized to 100 %, while one includes silica and the other does not. Students must use resources to predict how groundwater composition will change as a consequence of the observed weathering, and support those predictions using balanced chemical-weathering equations. Afterwards, they conduct a laboratory experiment in which they subject crushed rock to four types of solutions (acid solution, organic-rich solution, rainwater, and alkaline solution). The pH of each solution is measured, and subsequently adjusted after 24 and 48 hours. Solutions are sampled after 14 days. They are analyzed by ICP, and the compositions reported to students for comparison with their predictions.

Hinman, Nancy

207

Australian Severe Weather  

NSDL National Science Digital Library

The Australian Severe Weather Web site is maintained by self proclaimed severe weather enthusiasts Michael Bath and Jimmy Deguara. Other weatherphobes will fully appreciate what the authors have assembled. Everything from weather images, storm news, tropical cyclone data, bush fire and wild fire information, weather observation techniques, and even video clips and Web cam links. Although these other items make the site well rounded, the extensive amount of categorized weather pictures (which are quite extraordinary) are reason enough to visit.

208

What's the Weather?  

NSDL National Science Digital Library

In this lesson, students use daily observations, videos, and activities to learn about meteorology and the changing nature of weather. They will also identify weather events that are commonly reported in the news and discuss how weather affects lives. They should understand that weather can change daily and weather patterns change over the seasons, and that it has characteristics that can be measured and predicted. Suggestions for an optional field trip are also provided.

2005-01-01

209

IS CHEMICAL INDEX OF ALTERATION (CIA) A RELIABLE PROXY FOR CHEMICAL WEATHERING IN GLOBAL DRAINAGE BASINS?  

E-print Network

IS CHEMICAL INDEX OF ALTERATION (CIA) A RELIABLE PROXY FOR CHEMICAL WEATHERING IN GLOBAL DRAINAGE weathering of silicate rocks in continents as an important sink of atmospheric CO2 is of great significance) has been widely used as a proxy for chemical weathering in sediment source area. In this paper

Yang, Shouye

210

Estimation of the annual yield of organic carbon released from carbonates and shales by chemical weathering  

E-print Network

weathering Christian Di-Giovannia, Jean Robert Disnarb and Jean Jacques Macairea a Lab. de Géologie des matter yield induced by chemical weathering of carbonates and shales, considering their global surface carbonate rocks and shales weathering in major world watersheds, published by numerous authors. The results

Paris-Sud XI, Université de

211

Sharp decrease in long-term chemical weathering rates along an altitudinal transect  

E-print Network

Sharp decrease in long-term chemical weathering rates along an altitudinal transect� Cli�ord S long-term rates of chemical weathering and physical erosion across a steep climatic gradient analyses indicate that, relative to the parent rock, soils are less intensively weathered with increasing

Kirchner, James W.

212

Development of Rock Engineering  

NSDL National Science Digital Library

This chapter describes the development of rock engineering and provides introductory descriptions of the following concepts: rockbursts and elastic theory, discontinuous rock masses, engineering rock mechanics, geological data collection, laboratory testing of rock, rock mass classification, rock mass strength, in situ stress measurements, groundwater problems, rock reinforcement, excavation methods in rock, and analytical tools used in rock engineering.

2008-08-21

213

Rocks and Minerals  

NSDL National Science Digital Library

Rock Cycle Mineralogy 4 Kids Mineralogy 4 kids : rockin Internet site : the best place to learn about rocks and minerals Rock Cycle Map Rocks and Minerals Rocks and Minerals Pictures Rocks and Minerals Slide Show Rocks and Minerals Slide Show Earth Science Earth Science Uses for Minerals Metamorphic Rock Forming Sedimentary Rocks Observation ...

Richrigby

2010-02-23

214

Art Rocks with Rock Art!  

ERIC Educational Resources Information Center

This article discusses rock art which was the very first "art." Rock art, such as the images created on the stone surfaces of the caves of Lascaux and Altimira, is the true origin of the canvas, paintbrush, and painting media. For there, within caverns deep in the earth, the first artists mixed animal fat, urine, and saliva with powdered minerals…

Bickett, Marianne

2011-01-01

215

Weather Camp 2012 "Weather and Climate All Around Us"  

E-print Network

Weather Camp 2012 "Weather and Climate All Around Us" Are you interested in the weather? Come to Weather Camp at UNL What is Weather Camp? For more information Weather camp is a week long day camp for students who will be 11-14 years old at the time of the camp Most of the activities at Weather Camp 2012

Farritor, Shane

216

4.4 Nanoscale: Mineral Weathering Boundary RI Dorn, Arizona State University, Tempe, AZ, USA  

E-print Network

59 4.4.3.7 Silica Glaze Formation on Mars by Water Vapor Deposition 60 4.4.3.8 Nanoscale View of Rock-Surface Alternation of Dust 55 4.4.3.5 Silica Mobility in Rock Coatings and Case Hardening 58 4.4.3.6 Thermal Stresses in mineral weathering, silt production, rock coating behavior, geochemical pollution, thermal weathering from

Dorn, Ron

217

Rock Shots  

NSDL National Science Digital Library

Recently debuted on Adam Curry's METAVERSE site is Rock Shots, the first exclusive gallery of Rock 'n Roll photography on the Web by photographer Niels Van Iperen. Niels has been shooting musicians, fans and festivals for over 12 years in Europe and the U.S. His clients include the magazines Rolling Stone, Musician, Metal Hammer, OOR and Guitar World . Rock Shots brings you face to face with Aerosmith live in Brazil, Pearl Jam in their dressing room, the Red Hot Chili Peppers in a swimming pool and more ... on stage, backstage and audience rage. Portraits are viewed in Rock Shots through a custom-made search engine and is updated weekly with new artists.

Iperen, Niels V.

1995-01-01

218

Interactive Weather Information Network  

NSDL National Science Digital Library

Offered by the National Oceanic and Atmospheric Administration (NOAA), the Interactive Weather Information Network (IWIN) is a collection of interactive weather maps and satellite images that is updated every five seconds. Visitors can see cloud cover animation loops, NEXRAD Radar images of precipitation, a map of all current weather fronts, and an interactive national map to see information about any particular state. Other information on the site includes a listing of any active weather warnings, a link for world weather data, and more, making this a must-see site for all those users interested in the most current weather happenings anywhere.

2002-01-01

219

Pilot weather advisor  

NASA Technical Reports Server (NTRS)

The results of the work performed by ViGYAN, Inc., to demonstrate the Pilot Weather Advisor cockpit weather data system using a broadcast satellite communication system are presented. The Pilot Weather Advisor demonstrated that the technical problems involved with transmitting significant amount of weather data to an aircraft in-flight or on-the-ground via satellite are solvable with today's technology. The Pilot Weather Advisor appears to be a viable solution for providing accurate and timely weather information for general aviation aircraft.

Kilgore, W. A.; Seth, S.; Crabill, N. L.; Shipley, S. T.; Graffman, I.; Oneill, J.

1992-01-01

220

Edheads: Weather Activities  

NSDL National Science Digital Library

This great interactive resource allows you multiple opportunities to explore weather related concepts. After clicking start, you will learn how to report and predict the weather at the underground W.H.E.D weather caves! Each activity has three different levels, and each level is harder than the one before it. This resource also includes a teacher's guide (with pre- and post- tests) and links to additional weather related resources. These include a weather glossary, a Fahrenheit to Celsius & Celsius to Fahrenheit converter, and a link that provides information about interesting people in the weather field.

2010-01-01

221

Carbonatisation of Weathered Peridotites in Laboratory Experiments  

NASA Astrophysics Data System (ADS)

Enhanced in-situ carbonatisation of ultramafic rocks has been proposed as a strategy for a permanent and safe storage of CO2 in order to reduce anthropogenic greenhouse gas emissions (e.g., Kelemen and Matter 2008). This idea emerged from studies of natural examples demonstrating that ultramafic rocks react extensively with CO2 to form ophicarbonates. However, despite their Mg-rich nature, ultramafic rocks are often associated with calcite (CaCO3) rather than magnesite (MgCO3) and dolomite (CaMg(CO3)2). Whether these so-called ophicalcites represent sedimentary or tectonic breccias or are produced during hydrothermal alteration of ultramafic rocks, has been discussed for many years (e.g., Folk and McBride 1976). The view that reactions between hydrothermal fluids and ultramafic rocks can result in the formation of ophicalcite was recently supported by Beinlich et al. (2010), who documented Ca- and CO2-metasomatism and extreme Mg depletion in serpentinised and weathered peridotite clasts from the conglomerates of the Solund basin (SW Norway). This study also suggests that weathering is an important factor for the carbonatisation of ultramafic rocks. We have performed hydrothermal experiments on weathered peridotites in order to better constrain the mechanisms and conditions that trigger Mg-loss from ultramafic rocks and subsequent calcite precipitation. Un-crushed, partly serpentinised and weathered peridotite samples were allowed to react in a Ca-bearing saline solution under CO2 pressure (PCO2: 130-160 bar) at 200°C. We were able to illustrate the textural and chemical evolution during the reaction through a detailed comparison of the solid and fluid samples before and after the experiments. The initial samples showed a typical mesh texture with veins of serpentine surrounding meshes filled either with fresh or weathered olivine. The experimentally treated samples reveal a strongly reacted rim, predominantly composed of calcite, but still showing ghosts of the former mesh texture. Meshes that were initially filled with weathered olivine, were preferred sites of reaction relative to fresh olivine and serpentine. Dissolution of the mesh fillings and subsequent replacement by calcite resulted in Mg- and Si-enrichment in the fluid. The results confirm that hydrothermal alteration of ultramafic rocks may lead to Mg-depletion and ophicalcite formation and, in particular, highlight the role of weathering in enhancing the carbonatisation of peridotites. Our study has potential implications for industrial mineral sequestration of CO2 since weathering is commonly extensive in peridotites. The removal of Mg from the site of carbonatisation would be an undesired effect during CO2 injection into ultramafic rocks, but with a Ca-source available carbonatisation may still be effective. References: Beinlich, A., Austrheim, H., Glody, J., Erambert, M. and Andersen, T.B. (2010), Geochim. Cosmochim. Acta, in press. Folk, R.L. and McBride, E.F. (1976), Geology, 4(6): 327-332. Kelemen, P.B. and Matter, J. (2008), PNAS, 105(45): 17295-17300.

Hövelmann, J.; Austrheim, H.; Beinlich, A.; Munz, I. A.

2010-12-01

222

On Observing the Weather  

NSDL National Science Digital Library

In this article, Mount Washington Observatory meteorologist Tim Markle shares the ins and outs of his daily weather-observing routine and offers insights on making weather observations at home or at school.

Crane, Peter

2004-05-01

223

Favorite Demonstration: Differential Weathering  

NSDL National Science Digital Library

In this inquiry-based demonstration, the consumption of a Baby Ruth candy bar is used to nurture students' interest in chemical and physical weathering. In addition, two other concepts can be illustrated: the difference between weathering and erosion and

Francek, Mark

2002-10-01

224

Owlie Skywarn's Weather Book  

NSDL National Science Digital Library

This is an online activity book from the National Weather Service that teaches about hazardous weather. The site also includes links to kids sites for the Federal Emergency Management Agency (FEMA) and the National Oceanic and Atmospheric Agency (NOAA).

Garcia, Cris; Davis, Steve

2001-06-22

225

Weather in Antarctica  

NSDL National Science Digital Library

This homepage includes information about the weather in Antarctica and links to pages on the climate, wind chill, clouds, snow and ice, and pressure and storms of Antarctica. The current weather conditions updated automatically at various stations are also provided.

Hutchings, Thomas

1998-01-01

226

Winter Weather Emergencies  

MedlinePLUS

Severe winter weather can lead to health and safety challenges. You may have to cope with Cold related health problems, including ... there are no guarantees of safety during winter weather emergencies, you can take actions to protect yourself. ...

227

Weather Camp 2012: Weather and Climate All Around Us Are you interested in the weather?  

E-print Network

Weather Camp 2012: Weather and Climate All Around Us Are you interested in the weather? Come to Weather Camp at UNL! What is Weather Camp? For more information Weather camp is a week-long day camp for students who will be 11-14 years old at the time of the camp. Most of the activities at Weather Camp 2012

Farritor, Shane

228

Weather and Road Management  

NSDL National Science Digital Library

Anticipating and dealing with weather and the hazards it creates is a real challenge for those in departments of transportation. This module gives road and highway managers a basic understanding of meteorology and weather hazards so that they can better interpret weather forecast information used to make road management decisions. The module also highlights web-based forecast products available from the National Weather Service that can help in the decision-making process.

Comet

2008-07-21

229

Stormfax Weather Services  

NSDL National Science Digital Library

This site offers links to a variety of weather information, including national, international and local weather maps and forecasts, satellite and radar imagery, and severe weather warnings. There are also links to diverse resources such as fire maps, glacier inventories, snow depths, storm surges and tropical storms. There are reports and advisories about El Nino and La Nina. The site also has a glossary of weather terms and conversion charts for temperature, wind speed and atmospheric pressure.

2002-06-10

230

Enviropedia: Introduction to Weather  

NSDL National Science Digital Library

This resource provides an overview of weather, the day-to-day changes in temperature, air pressure, moisture, wind, cloudiness, rainfall and sunshine. Links embedded in the text provide access to descriptions of cloud types and to information on weather hazards such as fog, hurricanes, thunderstorms, and tornadoes. Other topics include meteorology, weather measurements, and weather mapping. Materials are also provided on the water cycle and its elements, such as evaporation, uplift and cooling of air, dew point, condensation, and precipitation.

2007-12-12

231

Fire Weather Climatology  

NSDL National Science Digital Library

The âFire Weather Climatologyâ module provides a comprehensive look at fire regions across the United States and characteristics of typical fire seasons in each region. In addition, critical fire weather patterns are described in terms of their development, duration and impact on fire weather. Numerous case studies provide examples and opportunities to practice recognizing these critical patterns and how they can affect fire ignition and spread. This module is part of the Advanced Fire Weather Forecasters Course.

Comet

2008-04-28

232

Weather Theory Introduction  

E-print Network

11-1 Weather Theory Chapter 11 Introduction Weather is an important factor that influences aircraft), visibility (clearness or cloudiness), and barometric pressure (high or low). The term weather can also apply of the atmosphere. Atmosphere The atmosphere is a blanket of air made up of a mixture of gases that surrounds

233

American Weather Stories.  

ERIC Educational Resources Information Center

Weather has shaped United States' culture, national character and folklore; at times it has changed the course of history. The seven accounts compiled in this publication highlight some of the nation's weather experiences from the hurricanes that threatened Christopher Columbus to the peculiar run of bad weather that has plagued American…

Hughes, Patrick

234

Predicting Seasonal Weather  

NSDL National Science Digital Library

This module is about a new method of predicting seasonal weather. The site describes the effects of El Nino on global weather and the accuracy of the new model. It includes links to classroom resources for a variety of weather-based units.

Dybas, Cheryl

2008-12-07

235

Extreme Weather on Earth  

NSDL National Science Digital Library

In this activity, students utilize a set of photographs and a 30 minute video on weather to investigate extreme weather events. They are posed with a series of questions that ask them to identify conditions predictive of these events, and record them on a worksheet. Climate and weather concepts defined.

Mika, Anna; Education, National G.

236

Space Weather Now  

NSDL National Science Digital Library

The Space Weather Now page is intended to give the non-technical user a "plain language" look at space weather. It includes information about relevant events and announcements, data from and about different instruments and satellites watching various aspects of space weather, alerts and advisories, daily themes of products and services, and links appropriate for the various groups of users.

Center, Space E.; Service, National O.

237

Climate and Weather  

NSDL National Science Digital Library

This video discusses the differences between climate and weather by defining and presenting examples of each. When presenting examples of weather, the video focuses on severe events and how meteorologists predict and study the weather using measurement, satellites, and radar. The climate focus is primarily on an overview of climate zones.

Geographic, National

238

METEOROLOGICAL Weather and Forecasting  

E-print Network

AMERICAN METEOROLOGICAL SOCIETY Weather and Forecasting EARLY ONLINE RELEASE This is a preliminary and interpretation of information from National Weather Service watches and warnings by10 decision makers such an outlier to the regional severe weather climatology. An analysis of the synoptic and13 mesoscale

239

Winter Weather Introduction  

E-print Network

Winter Weather Management #12;Introduction · Campus Facilities Staff · Other Campus Organizations #12;Purpose · Organize and coordinate the campus response to winter weather events to maintain campus for use by 7 AM. · Response will be modified depending upon forecast and current weather conditions. #12

Taylor, Jerry

240

Intelligent weather agent for aircraft severe weather avoidance  

E-print Network

avoidance capability has increased. In this thesis, an intelligent weather agent is developed for general aviation aircraft. Using a radar image from an onboard weather radar, the intelligent weather agent determines the safest path around severe weather...

Bokadia, Sangeeta

2012-06-07

241

Convective Weather Avoidance with Uncertain Weather Forecasts  

NASA Technical Reports Server (NTRS)

Convective weather events have a disruptive impact on air traffic both in terminal area and in en-route airspaces. In order to make sure that the national air transportation system is safe and efficient, it is essential to respond to convective weather events effectively. Traffic flow control initiatives in response to convective weather include ground delay, airborne delay, miles-in-trail restrictions as well as tactical and strategic rerouting. The rerouting initiatives can potentially increase traffic density and complexity in regions neighboring the convective weather activity. There is a need to perform rerouting in an intelligent and efficient way such that the disruptive effects of rerouting are minimized. An important area of research is to study the interaction of in-flight rerouting with traffic congestion or complexity and developing methods that quantitatively measure this interaction. Furthermore, it is necessary to find rerouting solutions that account for uncertainties in weather forecasts. These are important steps toward managing complexity during rerouting operations, and the paper is motivated by these research questions. An automated system is developed for rerouting air traffic in order to avoid convective weather regions during the 20- minute - 2-hour time horizon. Such a system is envisioned to work in concert with separation assurance (0 - 20-minute time horizon), and longer term air traffic management (2-hours and beyond) to provide a more comprehensive solution to complexity and safety management. In this study, weather is dynamic and uncertain; it is represented as regions of airspace that pilots are likely to avoid. Algorithms are implemented in an air traffic simulation environment to support the research study. The algorithms used are deterministic but periodically revise reroutes to account for weather forecast updates. In contrast to previous studies, in this study convective weather is represented as regions of airspace that pilots are likely to avoid. The automated system periodically updates forecasts and reassesses rerouting decisions in order to account for changing weather predictions. The main objectives are to reroute flights to avoid convective weather regions and determine the resulting complexity due to rerouting. The eventual goal is to control and reduce complexity while rerouting flights during the 20 minute - 2 hour planning period. A three-hour simulation is conducted using 4800 flights in the national airspace. The study compares several metrics against a baseline scenario using the same traffic and weather but with rerouting disabled. The results show that rerouting can have a negative impact on congestion in some sectors, as expected. The rerouting system provides accurate measurements of the resulting complexity in the congested sectors. Furthermore, although rerouting is performed only in the 20-minute - 2-hour range, it results in a 30% reduction in encounters with nowcast weather polygons (100% being the ideal for perfectly predictable and accurate weather). In the simulations, rerouting was performed for the 20-minute - 2-hour flight time horizon, and for the en-route segment of air traffic. The implementation uses CWAM, a set of polygons that represent probabilities of pilot deviation around weather. The algorithms were implemented in a software-based air traffic simulation system. Initial results of the system's performance and effectiveness were encouraging. Simulation results showed that when flights were rerouted in the 20-minute - 2-hour flight time horizon of air traffic, there were fewer weather encounters in the first 20 minutes than for flights that were not rerouted. Some preliminary results were also obtained that showed that rerouting will also increase complexity. More simulations will be conducted in order to report conclusive results on the effects of rerouting on complexity. Thus, the use of the 20-minute - 2-hour flight time horizon weather avoidance teniques performed in the simulation is expected to provide benefits for short-term weather avoidan

Karahan, Sinan; Windhorst, Robert D.

2009-01-01

242

Weathering Grade Classification of Granite Stone Monument Using Reflectance Spectroscopy  

NASA Astrophysics Data System (ADS)

Stone monument has been placed in field and exposed to rain and wind. This outdoor environment and air pollution induced weathering of stone monument. Weathering grade classification is necessary to manage and conserve stone monuments. Visual interpretation by geologist and laboratory experiments using specimens fallen off from the monument to avoid damage on the monument have been applied to classify weathering grade conventionally. Rocks and minerals absorb some particular wavelength ranges of electromagnetic energy by electronic process and vibrational process of composing elements and these phenomena produce intrinsic diagnostic spectral reflectance curve. Non-destructive technique for weathering degree assessment measures those diagnostic absorption features of weathering products and converts the depths of features related to abundance of the materials to relative weathering degree. We selected granite outcrop to apply conventional six folded weathering grade classification method using Schmidt hammer rebound teste. The correlations between Schmidt hammer rebound values and absorption depths of iron oxides such as ferric oxide in the vicinity of 0.9 micrometer wavelength and clay minerals such as illite and kaolinite in the vicinity of 2.2 micrometer wavelength, representative weathering products of granite, were analyzed. The Schmidt hammer rebound value decreased according to increase of absorption depths induced from those weathering products. Weathering grade classification on the granite stone monument was conducted by using absorption depths of weathering products This research is supported from National Research Institute of Cultural Heritage and we appreciate for this.

Hyun, C.; Roh, T.; Choi, M.; Park, H.

2009-05-01

243

Rock Pioneers  

NSDL National Science Digital Library

In this outdoor activity/field trip, learners investigate organisms that live along the ocean's rocky coast. Learners add bare rocks to an intertidal zone, and over the course of 6-8 weeks observe what plant and animals colonize (come to live) on the new rocks. The intertidal zone, covered by water during high tides and uncovered at low tides, is usually densely covered with marine organisms such as seaweeds, mussels, barnacles, snails, limpets, anemones and sea stars. Learners may not only discover pioneer organisms (first colonizers) of their new rocks, but other organisms that replace the first arrivals in the process of succession. This activity calls for multiple, weekly return visits to the intertidal zone.

Science, Lawrence H.

1981-01-01

244

External Resource: Weathering and Erosion  

NSDL National Science Digital Library

This activity includes background information about weathering, as well as simple demonstrations/activities to model how weather conditions contribute to weathering and erosion. Topics include: chemical weathering, dunes, erosion, floods, glaciers, physi

1900-01-01

245

Disintegration of sedimentary rocks used as building material: evaluation and quantification in 4D  

Microsoft Academic Search

Many natural building stones are subject to weathering processes that may lead to their disintegration. When rocks are exposed to extreme exogenous factors such as a combination of water and freeze-thaw cycles, they can deteriorate and cause problems concerning the maintenance of the structure. Some rock types are more susceptible to weathering processes than others, in which fluctuating environmental factors

J. Dewanckele; M. A. Boone; T. de Kock; V. Cnudde; M. N. Boone; Y. de Witte; K. Pieters; D. van Loo; L. van Hoorebeke; P. Jacobs

2009-01-01

246

Clay Mineral Formation and Transformation in Rocks and Soils  

Microsoft Academic Search

Three mechanisms for clay mineral formation (inheritance, neoformation, and transformation) operating in three geological environments (weathering, sedimentary, and diagenetic-hydrothermal) yield nine possibilities for the origin of clay minerals in nature. Several of these possibilities are discussed in terms of the rock cycle. The mineralogy of clays neoformed in the weathering environment is a function of solution chemistry, with the most

D. D. Eberl; V. C. Farmer; R. M. Barrer

1984-01-01

247

Plymouth State Weather Center  

NSDL National Science Digital Library

The Plymouth State Weather Center provides a variety of weather information, including a tropical weather menu with current and archived data on tropical depressions, storms, or hurricanes in the Atlantic or Eastern Pacific Oceans. An interactive Weather Product Generator allows students to make their own surface data maps and meteograms (24-hour summaries of weather at a specific location), and view satellite imagery. There are also interactive weather maps for the U.S., Canada, and Alaska that display the latest observations, and text servers which provide current written observations for New England and North America. A set of past and current weather data products provides information on minimum and maximum temperatures, wind chill, and heat index. In addition, there are collections of satellite loops/movies, radar/lightning images, loops, and movies, and a set of tutorials on clouds, the sun and its effects on the environment, and balanced atmospheric flows.

248

Avalanche Weather Forecasting  

NSDL National Science Digital Library

Avalanches form through the interaction of snowpack, terrain, and weather, the latter being the focus of this module. The module begins with basic information about avalanches, highlighting weather's role in their development. The rest of the module teaches weather forecasters how to make an avalanche weather forecast, that is, one in which key weather parameters are evaluated for their impact on avalanche potential. The forecasts are used primarily by avalanche forecasters, who integrate them with other information to determine when to issue avalanche hazard warnings. The module contains five cases that let users apply the avalanche weather forecast process to different combinations of snowpack, terrain, and weather conditions. It is a companion to the COMET module "Snowpack and Its Assessment," which describes snowpack development and various assessment techniques.

Comet

2010-09-30

249

Beyond the Weather Chart: Weathering New Experiences.  

ERIC Educational Resources Information Center

Describes an early childhood educator's approach to teaching children about rain, rainbows, clouds, precipitation, the sun, air, and wind. Recommends ways to organize study topics and describes experiments that can help children better understand the different elements of weather. (MOK)

Huffman, Amy Bruno

1996-01-01

250

Confined groundwater near the rockhead in igneous rocks in the Mid-Levels area, Hong Kong, China  

E-print Network

such a borehole indicates a confined groundwater condition important for slope stability study and foundation; Hydrogeology; Hydraulic conductivity; Rockhead; Weathered igneous rock; Saprolite 1. Introduction The study

Jiao, Jiu Jimmy

251

Sedimentary Rocks  

NSDL National Science Digital Library

This is a course handout that accompanies the discussion of the origin of sedimentary rocks. Topics include depositional tectonic settings, texture as an indicator of energy levels in the depositional environment, interpretation of various sandstones, and the influences of paleoclimate and source area lithology. Photos depict grain size and texture. Links are provided to the online Physical Geology resources at Georgia Perimeter College.

Gore, Pamela

1995-09-24

252

Classic Rock  

ERIC Educational Resources Information Center

While "early college" programs designed for high-school-age students are beginning to proliferate nationwide, a small New England school has been successfully educating teens for nearly four decades. In this article, the author features Simon's Rock, a small liberal arts college located in the Great Barrington, Massachusetts, that has been…

Beem, Edgar Allen

2004-01-01

253

Rock Grinding  

USGS Multimedia Gallery

Rocks from the Stillwater Mine are brought to the USGS in Denver, Colorado, where they are sledged and ground before entering the plasma melter at Zybek Advanced Products. __________ The USGS has created man-made moon dirt, or regolith, to help NASA prepare for upcoming moon explorations. Four ton...

2009-05-26

254

Stillwater Rocks  

USGS Multimedia Gallery

Rocks from the Stillwater Mine are brought to the USGS in Denver, Colorado, where they are ground before entering the plasma melter at Zybek Advanced Products. __________ The USGS has created man-made moon dirt, or regolith, to help NASA prepare for upcoming moon explorations. Four tons of the sim...

2009-05-26

255

Igneous Rocks  

NASA Astrophysics Data System (ADS)

“Igneous Rocks was written for undergraduate geology majors who have had a year of college-level chemistry and a course in mineralogy … and for beginning graduate students. Geologists working in industry, government, or academia should find this text useful as a guide to the technical literature up to 1981 and as an overview of topics with which they have not worked but which may have unanticipated pertinence to their own projects.” So starts the preface to this textbook.As one who works part time in research on igneous rocks, especially as they relate to mineral deposits, I have been looking for such a book with this avowed purpose in a field that has a choking richness of evolving terminology and a bewildering volume of interdisciplinary literature. In addition to the standard topics of igneous petrology, the book contains a chapter on the role of igneous activity in the genesis of mineral deposits, its value to geothermal energy, and the potential of igneous rocks as an environment for nuclear waste disposal. These topics are presented rather apologetically in the preface, but the author is to be applauded for including this chapter. The apology shows just how new these interests are to petrology. Recognition is finally coming that, for example, mineral deposits are not “sports of nature,” a view held even by many economic geologists as recently as the early 1960's; instead they are perfectly ordinary geochemical features formed by perfectly ordinary geologic processes. In fact, the mineral deposits and their attendant alteration zones probably have as much to tell us about igneous rocks as the igneous rocks have to tell us about mineral deposits.

Doe, Bruce R.

256

Weather and Atmosphere  

NSDL National Science Digital Library

In this unit, students learn the basics about weather and the atmosphere. They investigate materials engineering as it applies to weather and the choices available to us for clothing to counteract the effects of weather. Students have the opportunity to design and analyze combinations of materials for use in specific weather conditions. In the next lesson, students also are introduced to air masses and weather forecasting instrumentation and how engineers work to improve these instruments for atmospheric measurements on Earth and in space. Then, students learn the distinguishing features of the four main types of weather fronts that accompany high and low pressure air masses and how those fronts are depicted on a weather map. During this specific lesson, students learn different ways that engineers help with storm prediction, analysis and protection. In the final lesson, students consider how weather forecasting plays an important part in their daily lives by learning about the history of weather forecasting and how improvements in weather technology have saved lives by providing advance warning of natural disasters.

Integrated Teaching And Learning Program

257

Ecology and biology of microfungi from Antarctic rocks and soils  

Microsoft Academic Search

Cryptoendolithic microbial communities, living in porous sandstone rocks in the McMurdo Dry Valleys (Ross Desert) of Southern Victoria Land, Antarctica, were found within weathered pegmatite rocks in Northern Victoria Land, and the first endemic Antarctic fungal genus Friedmanniomyces endolithicus anam.?gen. and sp. nov. was isolated from this community. Selected microfungi from these communities and from soil were examined for the

Silvano Onofri; Massimiliano Fenice; Anna Rita Cicalini; Solveig Tosi; Anna Magrino; Sabina Pagano; Laura Selbmann; Laura Zucconi; Helen S. Vishniac; E. Imre Friedmann

2000-01-01

258

E-Rock: A Virtual Field Trip  

NSDL National Science Digital Library

This virtual field trip shows students the geologic features of Enchanted Rock, a dome of Precambrian granite located in central Texas. They can see small faults, fault gouge, close-up photos showing the texture of the granite, and a variety of features produced by weathering.

Reed, Robert

259

NOAA Daily Weather Maps  

NSDL National Science Digital Library

The charts on this website are the principal charts of the former Weather Bureau publication, "Daily Weather Map." They are the Surface Weather Map, the 500-Millibar Height Contours chart, the Highest and Lowest Temperatures chart, and the Precipitation Areas and Amounts chart. For each day, simple charts are arranged on a single page. These charts are the surface analysis of pressure and fronts, color shading, in ten degree intervals,of maximum and minimum temperature, 500-Millibar height contours, and color shaded 24-hour total precipitation. These charts act as links to their respective Daily Weather Map charts. All charts are derived from the operational weather maps prepared at the National Centers for Environmental Prediction, Hydrometeorological Prediction Center, National Weather Service.

Center, Hydrometeorological P.

2011-01-01

260

A framework for predicting global silicate weathering and CO2 drawdown rates over geologic time-scales  

E-print Network

A framework for predicting global silicate weathering and CO2 drawdown rates over geologic time (received for review February 15, 2008) Global silicate weathering drives long-time-scale fluctuations in atmospheric CO2. While tectonics, climate, and rock-type influence silicate weathering, it is unclear how

Hilley, George

261

Biogenic rock varnishes of the negev desert (Israel) an ecological study of iron and manganese transformation by cyanobacteria and fungi  

Microsoft Academic Search

The ecology of the microflora, which produces rock varnishes in the Negev is described. It is shown that biogenic rock varnishes may form within relatively short periods (1967–1981) on places where pre-existing varnishes were eliminated. Rock varnishes are thin coatings, mainly composed of Fe and Mn hydroxides and clay material. Biogenic rock varnishes form at places where “microbial weathering fronts”,

W. E. Krumbein; K. Jens

1981-01-01

262

Weather and Climate Data  

NSDL National Science Digital Library

The Weather and Climate Data site for the Center for Ocean-Land-Atmosphere Studies (COLA) contains analyses of current conditions and the state of the atmosphere; weather forecasts; metropolitan quick-look weather summaries and meteograms; short-term climate outlooks for temperature, precipitation and soil moisture; El Nino forecasts for understanding the ocean-atmosphere system; and maximum potential hurricane intensity maps showing potential minimum pressure and potential maximum winds for the oceans.

263

Space Weather Media Viewer  

NSDL National Science Digital Library

This is version 3 of the space Weather Media Viewer, created to work with the space Weather Action Center to see near-real time data and to provide additional images and resources available for educational use. It features easy downloads that can also be added to news reports and space weather reports. It was designed for ease in adding any media (videos, images) data.

2011-01-01

264

Winter weather activity  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. Weather Maker Simulator Use the weather simulation above to answer the following questions in complete sentences on paper. 1. In general, when are winds formed? 2. When winds are blowing, how can you get them to stop? 3. What usually happens when there is a large difference between the temperatures? 4. What happens when there is high ...

Frankovic, Whitney

2009-09-28

265

Weather Radar Fundamentals  

NSDL National Science Digital Library

This 2-hour module presents the fundamental principles of Doppler weather radar operation and how to interpret common weather phenomena using radar imagery. This is accomplished via conceptual animations and many interactive radar examples in which the user can practice interpreting both radar reflectivity and radar velocity imagery. Although intended as an accelerated introduction to understanding and using basic Doppler weather radar products, the module can also serve as an excellent refresher for more experienced users.

Comet

2012-03-21

266

RBSP Space Weather data  

NASA Astrophysics Data System (ADS)

On August 23, 2012, NASA will launch two identical probes into the radiation belts to provide unprecedented insight into the physical processes and dynamics of near-Earth space. The RBSP mission in addition to the scientific data return, provides a 1Kbps real-time space weather broadcast data in support of real time space weather modeling, forecast and prediction efforts. Networks of ground stations have been identified to downlink the space weather data. The RBSP instrument suites have selected space weather data to be broadcast from their collected space data on board the spacecraft, a subset from measurements based on information normally available to the instrument. The data subset includes particle fluxes at a variety of energies, and magnetic and electric field data. This selected space weather data is broadcast at all times through the primary spacecraft science downlink antennas when an observatory is not in a primary mission-related ground contact. The collected data will resolve important scientific issues and help researchers develop and improve various models for the radiation belts that can be used by forecasters to predict space weather phenomena and alert astronauts and spacecraft operators to potential hazards. The near real-time data from RBSP will be available to monitor and analyze current environmental conditions, forecast natural environmental changes and support anomaly resolution. The space weather data will be available on the RBSP Science Gateway at http://athena.jhuapl.edu/ and will provide access to the space weather data received from the RBSP real-time space weather broadcast. The near real-time data will be calibrated and displayed on the web as soon as possible. The CCMC will ingest the RBSP space weather data into real-time models. The raw space weather data will be permanently archived at APL. This presentation will provide a first look at RBSP space weather data products.

Weiss, M.; Fox, N. J.; Mauk, B. H.; Barnes, R. J.; Potter, M.; Romeo, G.; Smith, D.

2012-12-01

267

WWW - Wonderful Web Weather  

NSDL National Science Digital Library

This is a web quest for students to research weather forecasting using the Internet. Students work in groups to study how accurate weather forecasts are by tracking the weather for 3 days in several locations. Using graphs students then compare how each location scored in accuracy and present their findings to the class. This site contains links for students to use for more background information, a process for the students to follow, and evaluation rubrics for the student-produced graphs and presentation.

Parrish, Jason

2007-12-12

268

Weather and climate  

NASA Technical Reports Server (NTRS)

Recommendations for using space observations of weather and climate to aid in solving earth based problems are given. Special attention was given to: (1) extending useful forecasting capability of space systems, (2) reducing social, economic, and human losses caused by weather, (3) development of space system capability to manage and control air pollutant concentrations, and (4) establish mechanisms for the national examination of deliberate and inadvertent means for modifying weather and climate.

1975-01-01

269

Geologic relationships and geochronology of the Cenozoic volcanoes and interbedded weathered mantles of Yulinshan in Qiangtang, North Tibet  

Microsoft Academic Search

The Yulinshan accumulations of volcanic rocks and interbedded weathered mantles provide a unique chance for studying the processes\\u000a and environment of the formation of the planation surface in central Tibetan Plateau. Geochemical,40Ar\\/39Ar and K\\/Ar geochronologic investigations of the weathered mantles and high-potassium volcanic rocks reveal that the volcano-weathered\\u000a mantle accumulations formed under arid or semi-arid subtropic environment in 30–24 Ma.

Lin Ding; Yong Zhou; Jingjiang Zhang; Wanming Deng

2000-01-01

270

Poohbear Rock  

NASA Technical Reports Server (NTRS)

This image, taken by Sojourner's front right camera, was taken when the rover was next to Poohbear (rock at left) and Piglet (not seen) as it looked out toward Mermaid Dune. The textures differ from the foreground soil containing a sorted mix of small rocks, fines and clods, from the area a bit ahead of the rover where the surface is covered with a bright drift material. Soil experiments where the rover wheels dug in the soil revealed that the cloudy material exists underneath the drift.

Mars Pathfinder is the second in NASA's Discovery program of low-cost spacecraft with highly focused science goals. The Jet Propulsion Laboratory, Pasadena, CA, developed and manages the Mars Pathfinder mission for NASA's Office of Space Science, Washington, D.C. JPL is a division of the California Institute of Technology (Caltech).

1997-01-01

271

White Rock  

NASA Technical Reports Server (NTRS)

(Released 19 April 2002) The Science 'White Rock' is the unofficial name for this unusual landform which was first observed during the Mariner 9 mission in the early 1970's. As later analysis of additional data sets would show, White Rock is neither white nor dense rock. Its apparent brightness arises from the fact that the material surrounding it is so dark. Images from the Mars Global Surveyor MOC camera revealed dark sand dunes surrounding White Rock and on the floor of the troughs within it. Some of these dunes are just apparent in the THEMIS image. Although there was speculation that the material composing White Rock could be salts from an ancient dry lakebed, spectral data from the MGS TES instrument did not support this claim. Instead, the White Rock deposit may be the erosional remnant of a previously more continuous occurrence of air fall sediments, either volcanic ash or windblown dust. The THEMIS image offers new evidence for the idea that the original deposit covered a larger area. Approximately 10 kilometers to the southeast of the main deposit are some tiny knobs of similarly bright material preserved on the floor of a small crater. Given that the eolian erosion of the main White Rock deposit has produced isolated knobs at its edges, it is reasonable to suspect that the more distant outliers are the remnants of a once continuous deposit that stretched at least to this location. The fact that so little remains of the larger deposit suggests that the material is very easily eroded and simply blows away. The Story Fingers of hard, white rock seem to jut out like icy daggers across a moody Martian surface, but appearances can be deceiving. These bright, jagged features are neither white, nor icy, nor even hard and rocky! So what are they, and why are they so different from the surrounding terrain? Scientists know that you can't always trust what your eyes see alone. You have to use other kinds of science instruments to measure things that our eyes can't see . . . things like information about what kinds of minerals make up the landforms. Mars scientists once thought, for instance, that these unusual features might be vast hills of salt, the dried up remains of a long-ago, evaporated lake. Not so, said an instrument on the Mars Global Surveyor spacecraft, which revealed that the bright material is probably made up of volcanic ash or windblown dust instead. And talk about a cyclical 'ashes to ashes, dust to dust' story! Particles of this material fell and fell until they built up quite a sedimentary deposit, which was then only eroded away again by the wind over time, leaving the spiky terrain seen today. It looks white, but its apparent brightness arises from the fact that the surrounding material is so dark. Of course, good eyesight always helps in understanding. A camera on Mars Global Surveyor with close-up capabilities revealed that sand dunes are responsible for the smudgy dark material in the bright sediment and around it. But that's not all. The THEMIS camera on the Mars Odyssey spacecraft that took this image reveals that this ashy or dusty deposit once covered a much larger area than it does today. Look yourself for two small dots of white material on the floor of a small crater nearby (center right in this image). They preserve a record that this bright deposit once reached much farther. Since so little of it remains, you can figure that the material probably isn't very hard, and simply blows away. One thing's for sure. No one looking at this image could ever think that Mars is a boring place. With all of its bright and dark contrasts, this picture would be perfect for anyone who loves Ansel Adams and his black-and-white photography.

2002-01-01

272

Pilot Weather Advisor System  

NASA Technical Reports Server (NTRS)

The Pilot Weather Advisor (PWA) system is an automated satellite radio-broadcasting system that provides nearly real-time weather data to pilots of aircraft in flight anywhere in the continental United States. The system was designed to enhance safety in two distinct ways: First, the automated receipt of information would relieve the pilot of the time-consuming and distracting task of obtaining weather information via voice communication with ground stations. Second, the presentation of the information would be centered around a map format, thereby making the spatial and temporal relationships in the surrounding weather situation much easier to understand

Lindamood, Glenn; Martzaklis, Konstantinos Gus; Hoffler, Keith; Hill, Damon; Mehrotra, Sudhir C.; White, E. Richard; Fisher, Bruce D.; Crabill, Norman L.; Tucholski, Allen D.

2006-01-01

273

Weather assessment and forecasting  

NASA Technical Reports Server (NTRS)

Data management program activities centered around the analyses of selected far-term Office of Applications (OA) objectives, with the intent of determining if significant data-related problems would be encountered and if so what alternative solutions would be possible. Three far-term (1985 and beyond) OA objectives selected for analyses as having potential significant data problems were large-scale weather forecasting, local weather and severe storms forecasting, and global marine weather forecasting. An overview of general weather forecasting activities and their implications upon the ground based data system is provided. Selected topics were specifically oriented to the use of satellites.

1977-01-01

274

Winter Storm (weather)  

NSDL National Science Digital Library

This project explores factors that help create severe winter weather. An interactive simulation provides hands-on experience, followed by guiding questions and resource exploration. First think about these questions: 1. What is your favorite aspect of winter weather? 2. How does the weather effect your everyday life? Form groups of THREE. Explore the following simulation: Weather Maker Simulator Use the simulation to answer the following questions on paper... 1. In general, when are winds formed? 2. When winds are blowing, how can you ...

Miller, Aubree

2009-09-28

275

Washington Post Weather  

NSDL National Science Digital Library

The Washington Post makes a bid for the already crowded Internet weather market with WeatherPost. Coverage includes current conditions and four-day forecasts for 3,600 cities worldwide, as well as snapshot and time-lapse satellite maps (provided by Accu Weather). For US cities, users may also access UV and air quality maps and data, as well as seasonal maps (snow cover, tanning index, heat index, and BeachCast) and other radar images such as precipitation. Users may enter a city name into the homepage search box, or may browse by country or state/province. The historical weather database offers compiled monthly average weather data for nearly 1,000 cities worldwide; the database is searchable. An aspect of the site that sets it apart from many other weather pages is the weather reference desk, which includes a weather glossary, weather calculators (JavaScript converters for temperature, wind chill, heat index, etc.) and a page devoted to storm chasers.

1997-01-01

276

Space Weather: Welcome, SEC  

NSDL National Science Digital Library

This video presentation welcomes the Space Weather Prediction Center, formerly known as the Space Environment Center or SEC to the National Weather Service (NWS) as an operational entity of the National Centers for Environmental Prediction (NCEP) family. Describing the ways in which space weather affects global communications and power resources, it demonstrates the importance of space weather forecasting as a part of the NWS family of services. With the inclusion of SWPC, the NWS now provides environmental understanding from the sun to the sea.

Comet

2005-01-11

277

External Resource: Rock and Roll  

NSDL National Science Digital Library

This page contains information on exactly what a rock is, as well as a diagram of the rock cycle. Topics include: characteristics of rocks, types of rocks, igneous rocks, metamorphic rocks, and sedimentary rocks.

1900-01-01

278

Iron isotopic fractionation during continental weathering  

SciTech Connect

The biological activity on continents and the oxygen content of the atmosphere determine the chemical pathways through which Fe is processed at the Earth's surface. Experiments have shown that the relevant chemical pathways fractionate Fe isotopes. Measurements of soils, streams, and deep-sea clay indicate that the {sup 56}Fe/{sup 54}Fe ratio ({delta}{sup 56}Fe relative to igneous rocks) varies from +1{per_thousand} for weathering residues like soils and clays, to -3{per_thousand} for dissolved Fe in streams. These measurements confirm that weathering processes produce substantial fractionation of Fe isotopes in the modern oxidizing Earth surface environment. The results imply that biologically-mediated processes, which preferentially mobilize light Fe isotopes, are critical to Fe chemistry in weathering environments, and that the {delta}{sup 56}Fe of marine dissolved Fe should be variable and negative. Diagenetic reduction of Fe in marine sediments may also be a significant component of the global Fe isotope cycle. Iron isotopes provide a tracer for the influence of biological activity and oxygen in weathering processes through Earth history. Iron isotopic fractionation during weathering may have been smaller or absent in an oxygen-poor environment such as that of the early Precambrian Earth.

Fantle, Matthew S.; DePaolo, Donald J.

2003-10-01

279

Meteorology:Meteorology: Weather and ClimateWeather and Climate  

E-print Network

1 Meteorology:Meteorology: Weather and ClimateWeather and Climate Large Scale Weather SystemsLarge--scale Weather Systemsscale Weather Systems Tropical cyclones (1-2) Location, Structure, Life-cycle Formation and modification, airmasses that effect the British Isles Airmasses affecting the British Isles

280

Weather and emotional state  

NASA Astrophysics Data System (ADS)

Introduction Given the proven effects of weather on the human organism, an attempt to examine its effects on a psychic and emotional level has been made. Emotions affect the bio-tonus, working ability and concentration, hence their significance in various domains of economic life, such as health care, education, transportation, tourism, etc. Data and methods The research has been made in Sofia City within a period of 8 months, using 5 psychological methods (Eysenck Personality Questionnaire (EPQ), State-Trait Anxiety Inventory (STAI), Test for Self-assessment of the emotional state (developed by Wessman and Ricks), Test for evaluation of moods and Test "Self-confidence - Activity - Mood" (developed by the specialists from the Military Academy in Saint Petersburg). The Fiodorov-Chubukov's complex-climatic method was used to characterize meteorological conditions because of the purpose to include in the analysis a maximal number of meteorological elements. 16 weather types are defined in dependence of the meteorological elements values according to this method. Abrupt weather changes from one day to another, defined by the same method, were considered as well. Results and discussions The results obtained by t-test show that the different categories of weather lead to changes in the emotional status, which indicates a character either positive or negative for the organism. The abrupt weather changes, according to expectations, have negative effect on human emotions but only when a transition to the cloudy weather or weather type, classified as "unfavourable" has been realized. The relationship between weather and human emotions is rather complicated since it depends on individual characteristics of people. One of these individual psychological characteristics, marked by the dimension "neuroticism", has a strong effect on emotional reactions in different weather conditions. Emotionally stable individuals are more "protected" to the weather influence on their emotions, while those who are emotionally unstable have a stronger dependence to the impacts of the weather.

Spasova, Z.

2010-09-01

281

Welcome to Rock Day  

NSDL National Science Digital Library

Seeking to revitalize a unit on rocks, sand, and soil for first-graders, the authors created new hands-on lessons. These included testing the hardness of rocks, making models of the Earth, and sorting rocks. As a culminating activity, students participated in a series of Rock Day events that focused on the three different types of rocks and the rock cycle.

Benhart, Jeaneen; Varelas, Maria; National Science Teachers Association (NSTA)

2004-01-01

282

Hydrologic regulation of chemical weathering and the geologic carbon cycle.  

PubMed

Earth's temperature is thought to be regulated by a negative feedback between atmospheric CO2 levels and chemical weathering of silicate rocks that operates over million-year time scales. To explain variations in the strength of the weathering feedback, we present a model for silicate weathering that regulates climatic and tectonic forcing through hydrologic processes and imposes a thermodynamic limit on weathering fluxes, based on the physical and chemical properties of river basins. Climate regulation by silicate weathering is thus strongest when global topography is elevated, similar to the situation today, and lowest when global topography is more subdued, allowing planetary temperatures to vary depending on the global distribution of topography and mountain belts, even in the absence of appreciable changes in CO2 degassing rates. PMID:24625927

Maher, K; Chamberlain, C P

2014-03-28

283

Designing a Weather Station  

ERIC Educational Resources Information Center

The collection and analysis of weather data is crucial to the location of alternate energy systems like solar and wind. This article presents a design challenge that gives students a chance to design a weather station to collect data in advance of a large wind turbine installation. Data analysis is a crucial part of any science or engineering…

Roman, Harry T.

2012-01-01

284

Mild and Wild Weather.  

ERIC Educational Resources Information Center

Presents background information and six activities that focus on clouds, precipitation, and stormy weather. Each activity includes an objective, recommended age level(s), subject area(s), and instructional strategies. Also provided are two ready-to-copy pages (a coloring page on lightning and a list of weather riddles to solve). (JN)

NatureScope, 1985

1985-01-01

285

People and Weather.  

ERIC Educational Resources Information Center

Provides: (1) background information on ways weather influences human lives; (2) activities related to this topic; and (3) a ready-to-copy page with weather trivia. Each activity includes an objective, list of materials needed, recommended age level(s), subject area(s), and instructional strategies. (JN)

NatureScope, 1985

1985-01-01

286

Weather Cardboard Carpentry  

ERIC Educational Resources Information Center

Included are instructions and diagrams for building weather instruments (wind vane, Celsius temperature scale, and anemometer) from simple tools and Tri-Wall, a triple-thick corrugated cardboard. Ordering sources for Tri-Wall are listed. Additional weather instruments that can be constructed are suggested. (CS)

DeBruin, Jerome E.

1977-01-01

287

Home Weatherization Visit  

SciTech Connect

Secretary Steven Chu visits a home that is in the process of being weatherized in Columbus, OH, along with Ohio Governor Ted Strickland and Columbus Mayor Michael Coleman. They discuss the benefits of weatherization and how funding from the recovery act is having a direct impact in communities across America.

Chu, Steven

2009-01-01

288

Weathering warming in Colorado  

SciTech Connect

This article describes the results of a field experiment heating patches of a subalpine meadow in the Rocky Mountains to determine what will weather and what will weather under projected global warming. The problems with actually measuring the feedback is discussed, along with the changes which come as the meadow is heated.

Gillis, A.M.

1996-03-01

289

Teacher's Weather Sourcebook.  

ERIC Educational Resources Information Center

This book is a teaching resource for the study of weather-related phenomena. A "weather unit" is often incorporated into school study because of its importance to our daily lives and because of its potential to cut across disciplinary content. This book consists of two parts. Part I covers the major topics of atmospheric science such as the modern…

Konvicka, Tom

290

Erosion and Weathering  

NSDL National Science Digital Library

Weathering and erosion work together as natural forces, removing and transporting material. Sediments, the by-products of these processes, are subsequently deposited to produce characteristic landforms such as dunes, deltas, and glacial moraines. This slide show presents images of landforms that result from erosion and weathering, as well as measures designed to mitigate their unwanted effects.

291

Critical Fire Weather Patterns  

E-print Network

-- 1.1 Typical Summer Weather Cycle PDT -- 1.1 Dry Thunderstorms PHX -- 1.1 North Winds PHX -- 2 Thunderstorms RNO -- 1.1 Washoe Zephyr RNO -- 2.1 Winds & Thunderstorms SAC -- 1.1 Pre--Frontal Winds SLC -- 1 days. Normally the pacific weather front will have enough instability for a few dry thunderstorms

Clements, Craig

292

What Is Space Weather?  

NSDL National Science Digital Library

This resource provides a brief overview of the phenomenon known as space weather, which happens when energetic particles emitted by the Sun impact the Earth's magnetosphere. Users can view images, video clips, and animations of auroras and other types of space weather. A set of links to related websites is also provided.

293

Benign Weather Modification.  

National Technical Information Service (NTIS)

Weather modification is a technology once embraced by the U.S. military as a tool to help both wartime and peacetime missions. However, interest in the ability to modify weather has waned over recent years and is now nearly non-existent. This study examin...

B. E. Coble

1996-01-01

294

Benign Weather Modification.  

National Technical Information Service (NTIS)

Weather modification is a technology once embraced by the United States (US) military as a tool to help both wartime and peacetime missions. However, interest in the ability to modify weather has waned over recent years and is now nearly nonexistent. This...

B. B. Coble

1997-01-01

295

Weathering Database Technology  

ERIC Educational Resources Information Center

Collecting weather data is a traditional part of a meteorology unit at the middle level. However, making connections between the data and weather conditions can be a challenge. One way to make these connections clearer is to enter the data into a database. This allows students to quickly compare different fields of data and recognize which…

Snyder, Robert

2005-01-01

296

Exercising in Cold Weather  

MedlinePLUS

... www.nia.nih.gov/Go4Life Exercising in Cold Weather Exercise has benefits all year, even during winter. ... activities when it’s cold outside: l Check the weather forecast. If it’s very windy or cold, exercise ...

297

Fabulous Weather Day  

ERIC Educational Resources Information Center

Each year, first graders at Kensington Parkwood Elementary School in Kensington, Maryland, look forward to Fabulous Weather Day. Students learn how meteorologists collect data about the weather, how they study wind, temperature, precipitation, basic types/characteristics of clouds, and how they forecast. The project helps the students grow in…

Marshall, Candice; Mogil, H. Michael

2007-01-01

298

On Observing the Weather  

ERIC Educational Resources Information Center

Rain, sun, snow, sleet, wind... the weather affects everyone in some way every day, and observing weather is a terrific activity to attune children to the natural world. It is also a great way for children to practice skills in gathering and recording information and to learn how to use simple tools in a standardized fashion. What better way to…

Crane, Peter

2004-01-01

299

From Rocks to Cement. What We Make. Science and Technology Education in Philippine Society.  

ERIC Educational Resources Information Center

This module deals with the materials used in making concrete hollow blocks. Topics discussed include: (1) igneous, metamorphic, and sedimentary rocks; (2) weathering (the process of breaking down rocks) and its effects on rocks; (3) cement; (4) stages in the manufacturing of Portland cement; and (5) the transformation of cement into concrete…

Philippines Univ., Quezon City. Science Education Center.

300

Integrated resistivity surveys for delineation of fractures for ground water exploration in hard rock areas  

Microsoft Academic Search

Acute shortage of ground water in hard rock areas is well known. Ground water occurs in limited areal extent in secondary porosity generally developed due to weathering, fracturing, jointing, faulting etc. within the hard rock formations. These structural changes (fractures etc.) are sparsely distributed in the hard rock areas. Gradient profiling followed by geoelectrical sounding has been successfully utilized to

G. S. Yadav; Shashi Kant Singh

2007-01-01

301

Geochemistry of large river suspended sediments: Silicate weathering or recycling tracer?  

SciTech Connect

This study focuses on the major and trace element composition of suspended sediments transported by the world's largest rivers. Its main purpose is to answer the following question: is the degree of weathering of modern river-borne particles consistent with the estimated river dissolved loads derived from silicate weathering? In agreement with the well known mobility of elements during weathering of continental rocks, the authors confirm that river sediments are systematically depleted in Na, K, Ba with respect to the Upper Continental Crust. For each of these mobile elements, a systematics of weathering indexes of river-borne solids is attempted. A global consistency is found between all these indexes. Important variations in weathering intensities exist. A clear dependence of weathering intensities with climate is observed for the rivers draining mostly lowlands. However, no global correlation exists between weathering intensities and climatic or relief parameters because the trend observed for lowlands is obscured by rivers draining orogenic zones. An inverse correlation between weathering intensities and suspended sediment concentrations is observed showing that the regions having the highest rates of physical denudation produce the least weathered sediments. Finally, chemical and physical weathering are compared through the use of a simple steady state model. The authors show that the weathering intensities of large river suspended sediments can only be reconciled with the (silicate-derived) dissolved load or rivers, by admitting that most of the continental rocks submitted to weathering in large river basins have already suffered previous weathering cycles. A simple graphical method is proposed for calculating the proportion of sedimentary recycling in large river basins. Finally, even if orogenic zones produce weakly weathered sediments, the authors emphasize the fact that silicate chemical weathering rates (and hence CO{sub 2} consumption rates by silicate weathering) are greatly enhanced in mountains simply because the sediment yields in orogenic drainage basins are higher. Hence, the parameters that control chemical weathering rates would be those that control physical denudation rates.

Gaillardet, J.; Dupre, B.; Allegre, C.J.

1999-12-01

302

Scholastic: Weather Watch  

NSDL National Science Digital Library

The Weather Watch series of online projects investigates seasonal weather phenomena. Students discover the scientific explanations for these events, and use tools and resources for enhanced research. The Hurricanes project allows students to monitor patterns and plot the progression of hurricanes. The Winter Storms project contains an interactive weather maker allowing students to create different weather patterns by changing factors. A winter storm timeline provides stories of the harshest blizzards that have occurred in the U.S. The Weather Reporters project includes a selection of hands-on science experiments for classroom participation, leading up to sharing results online with students worldwide. Each project provides assessment tools and lesson plan suggestions for educators. Links are provided for additional resources.

303

Thermal Inertia of Rocks and Rock Populations  

NASA Technical Reports Server (NTRS)

The effective thermal inertia of rock populations on Mars and Earth is derived from a model of effective inertia versus rock diameter. Results allow a parameterization of the effective rock inertia versus rock abundance and bulk and fine component inertia. Additional information is contained in the original extended abstract.

Golombek, M. P.; Jakosky, B. M.; Mellon, M. T.

2001-01-01

304

Pop Rocks Experiment 25 Pop rock packages  

E-print Network

Pop Rocks Experiment Materials · 25 Pop rock packages · Four 9 inch balloons · Four 16 oz sodas of it, tell them that many people believe that eating pop rocks and drinking soda at the same time will make your stomach explode. Grand Finale: Pop rocks & soda 1. Ask the kids what they think will happen

Benitez-Nelson, Claudia

305

Edible Rocks  

NSDL National Science Digital Library

This lesson has been designed as a comfortable introduction to describing meteorites. It helps students become better observers by making a connection between the familiar (candy bars) and the unfamiliar (meteorites). Edible "rocks" are used in a scientific context, showing students the importance of observation, teamwork and communication skills. In everyday terms, students draw and describe the food. They pair their observations with short descriptions that are in geologic "Field Note" style. As the teacher and class review, appropriate geologic terminology may be substituted by the teacher and subsequently embraced by even very young students.

Lindstrom, Marilyn

306

Classifying Rocks  

NSDL National Science Digital Library

Plants and animals are usually organized by their family tree (origin) and by their physical and genetic characteristics. This activity helps to demonstrate to students that geologists do the same with rocks, which are usually organized by their origin and by their physical and chemical characteristics. To have a better understanding of nature and as one of the initial steps of scientific understanding, it is important for humans to organize nature into groups. This site has a list of materials, background information, a detailed procedure, and a suggestion for assessment.

307

Predicting the Weather  

NSDL National Science Digital Library

This Topic in Depth explores the science behind predicting the weather. First, the United States Search and Rescue Task Force describe the basic tools and knowledge used to create weather forecasts (1). Students can find concise, clear explanations of weather, fronts and air masses, high and low pressure, precipitation, and water vapor and humidity as well. By performing the activities presented in the second website, fourth grade students can learn about weather instruments and data collection (2). This website, produced by the Government of Saskatchewan, also explores how the weather can impact local communities. Third, Edheads offers a Macromedia Flash Player enhanced interactive module allowing students to predict the weather by examining weather maps (3 ). Through this website, users can become familiar with the concepts of warm and cold fronts, wind direction and speed, air pressure, and humidity. The fourth website, supplied by Annenberg / CPB, discusses weather satellites, Doppler radar, and additional tools forecasters use to predict the weather (4). Students can find a wind chill calculator along with a brief discussion of the history of forecasting and weather lore. Next, NOAA provides graphics for five forecast models: the ETA, the Global Forecast System (GFS), the Wave Watch III (WW3), the Nested Grid model (NGM), and the Rapid Update Cycle (RUC) (5). Outputs are available for North America, North Pacific, Western North Atlantic, and the Polar Ice Drift. Users can find links to detailed descriptions of the inputs and history of each model. Sixth, the British government's Met Office describes numerical modeling and its components (6). Students and educators can learn about the future in forecasting as well as educational opportunities with the Cooperative Program for Meteorology, Education, and Training (COMET).

308

All About Rocks  

NSDL National Science Digital Library

We will be learning about different types of rocks today.This project will teach you how to sort rocks based upon color, hardness, texture, layering, and particle size. We will even see a video of new rocks being formed! Visit this link to read an intro about rocks. Intro to Rocks Then visit these three links 1) Metamorphic Rocks 2) Igneous Rocks 3) Sedimentary Rocks Now answer these questions: 1) What types of rocks do you think you would find in your backyard? 2)Compare and contrast 2 of the 3 different types of rocks. 3)What is your favorite ...

Heffernan, Laura

2010-06-21

309

Sliding Rocks on Racetrack Playa, Death Valley National Park: First Observation of Rocks in Motion  

PubMed Central

The engraved trails of rocks on the nearly flat, dry mud surface of Racetrack Playa, Death Valley National Park, have excited speculation about the movement mechanism since the 1940s. Rock movement has been variously attributed to high winds, liquid water, ice, or ice flotation, but has not been previously observed in action. We recorded the first direct scientific observation of rock movements using GPS-instrumented rocks and photography, in conjunction with a weather station and time-lapse cameras. The largest observed rock movement involved >60 rocks on December 20, 2013 and some instrumented rocks moved up to 224 m between December 2013 and January 2014 in multiple move events. In contrast with previous hypotheses of powerful winds or thick ice floating rocks off the playa surface, the process of rock movement that we have observed occurs when the thin, 3 to 6 mm, “windowpane” ice sheet covering the playa pool begins to melt in late morning sun and breaks up under light winds of ?4–5 m/s. Floating ice panels 10 s of meters in size push multiple rocks at low speeds of 2–5 m/min. along trajectories determined by the direction and velocity of the wind as well as that of the water flowing under the ice. PMID:25162535

Lorenz, Ralph D.; Ray, Jib; Jackson, Brian

2014-01-01

310

Environmental Education Tips: Weather Activities.  

ERIC Educational Resources Information Center

Provides weather activities including questions, on weather, heating the earth's surface, air, tools of the meteorologist, clouds, humidity, wind, and evaporation. Shows an example of a weather chart activity. (RT)

Brainard, Audrey H.

1989-01-01

311

Weather and Fire  

E-print Network

Recent cooler temperatures and rain showers have moderated fire behavior across Alaska. “The fires are taking a breather, but our firefighters are not, ” said Pete Buist, Fire Information Officer. When the weather provides a break like this, firefighters take advantage of it by redoubling their efforts and maximizing progress towards completing fire management objectives. Yesterday’s weather included over 3,000 lightning strikes across the state and scattered showers from inch to nearly an inch in some locations. Mild temperatures and scattered showers are expected to continue into the weekend. A thermal Weather is one of the most significant factors in determining the severity of wildland fires. The intensity of fires and the rate with which they spread is directly related to the wind speed, temperature and relative humidity. Accurate and timely weather information is vital to the planning and execution of strategies for suppressing wildfires. trough is moving northward across Alaska, but thunderstorms will decrease and temperatures will increase over the next few days. A high pressure ridge is attempting to move westward into the Interior, and if successful, warm weather could return next week. For additional details on fire weather see the AICC weather page at

unknown authors

2010-01-01

312

Fire Weather Forecasting: Clear Communications  

NSDL National Science Digital Library

The âFire Weather Forecasting: Clear Communicationsâ distance learning module offers best practices for Fire Weather Forecasters needing to communicate weather information when deployed in the field. The 30-minute module defines strategies for communicating with Weather Forecast Offices and with customers. Examples include writing a useful fire weather forecast discussion and undertaking proper planning to quickly and accurately disseminate information. This distance learning module is part of the Advanced Fire Weather Forecasters Course.

Comet

2008-03-05

313

Phosphine from rocks: mechanically driven phosphate reduction?  

PubMed

Natural rock and mineral samples released trace amounts of phosphine during dissolution in mineral acid. An order of magnitude more phosphine (average 1982 ng PH3 kg rock and maximum 6673 ng PH3/kg rock) is released from pulverized rock samples (basalt, gneiss, granite, clay, quartzitic pebbles, or marble). Phosphine was correlated to hardness and mechanical pulverization energy of the rocks. The yield of PH3 ranged from 0 to 0.01% of the total P content of the dissolved rock. Strong circumstantial evidence was gathered for reduction of phosphate in the rock via mechanochemical or "tribochemical" weathering at quartz and calcite/marble inclusions. Artificial reproduction of this mechanism by rubbing quartz rods coated with apatite-phosphate to the point of visible triboluminescence, led to detection of more than 70 000 ng/kg PH3 in the apatite. This reaction pathway may be considered a mechano-chemical analogue of phosphate reduction from lightning or electrical discharges and may contribute to phosphine production via tectonic forces and processing of rocks. PMID:16294866

Glindemann, Dietmar; Edwards, Marc; Morgenstern, Peter

2005-11-01

314

Fossil microorganisms and formation of Early Precambrian weathering crusts  

Microsoft Academic Search

Weathering crusts are the only reliable evidences of continental conditions existence, and often are the only source of information about exogenous processes and subsequently about conditions under which the development of biosphere occurred. Complex of diverse fossil microorganisms was discovered in result of electronic-microscope investigations. Chemical composition of discovered fossils is identical to that of the host rocks and is

M. M. Astafieva; A. Yu. Rozanov; A. B. Vrevsky; N. A. Alfimova; V. A. Matrenichev; R. B. Hoover

2009-01-01

315

Iron-sulfur mineralogy of Mars: Magmatic evolution and chemical weathering products  

Microsoft Academic Search

Models for the evolution of sulfide minerals on Mars and reaction pathways to their oxidative weathering products in Martian regolith have been proposed based on petrogenetic associations between komatiitic rock types, Viking geochemical data, SNC meteorites, and terrestrial Fe-Ni sulfide deposits. To test the weathering model, komatiitic pyrrhotites and olivines were exposed to sulfuric acid solutions, with and without dissolved

Roger G. Burns; Duncan S. Fisher

1990-01-01

316

Evolution of porosity and diffusivity associated with chemical weathering of a basalt clast  

E-print Network

in their chemistry and porosity. In low-porosity rocks, such as basalts, changes in porosity, resulting from chemical processes. Our inability to link chemical and mineralogical changes within a weathering environmentEvolution of porosity and diffusivity associated with chemical weathering of a basalt clast Alexis

317

Effects of pure silica coatings on thermal emission spectra of basaltic rocks: Considerations for Martian surface mineralogy  

Microsoft Academic Search

(1) On Mars, silica derived from chemical weathering could precipitate to coat rocks and particles. We suggest that rock coatings of secondary amorphous silica may account for a widespread Martian surface spectral unit previously modeled as andesite or weathered basalt. In a laboratory study, we investigated the effects of synthetic silica coatings on thermal infrared (TIR) spectroscopic measurements. Secondary amorphous

Michael D. Kraft; Joseph R. Michalski; Thomas G. Sharp

2003-01-01

318

World Weather Information Service  

NSDL National Science Digital Library

The World Meteorological Organization Web site offers the World Weather Information Service page. Here, visitors will find official weather forecasts and climatological information for selected cities worldwide. Users choose a particular continent and country, and are then presented with a list of various cities they can get information on. This includes the date and time of the current forecast, minimum and maximum temperatures for that day, a general cloud description, and a monthly review of various data for that city. If for nothing else, the site does a good job of providing a very straightforward and easy way to find weather information from hundreds of cities around the globe.

319

Weather Map Assignment  

NSDL National Science Digital Library

I gave this assignment so that students could relate real-time weather changes to mid-latitude cyclones and air mass movement. Basically, by the time I assigned the project, we have discussed all the necessary weather phenomena and this project gives the students a way to apply what we have discussed to "reality" by explaining why the weather occurred the way it did over a short time period. It also provides me with a way to assess how well they are able to tie all the major concepts together, which is one of the goals of the course.

Brueseke, Matt

320

Weather Observing Fundamentals  

NSDL National Science Digital Library

"Weather Observing Fundamentals" provides guidance for U.S. Navy Aerographer's Mates, Quartermasters, and civilian observers tasked with taking and reporting routine, special, and synoptic observations. Although the focus of this lesson is on shipboard observations, much of the content applies to land-based observing and reporting as well. The lesson details standard procedures for taking accurate weather observations and for encoding those observations on COMNAVMETOCCOM Report 3141/3. Exercises throughout the lesson and four weather identification drills at the end provide learners with opportunities to practice and build their skills. The lesson covers a large amount of content. You may wish to work through the material in multiple sessions.

Comet

2014-03-11

321

Weathering and Erosion  

NSDL National Science Digital Library

This Classroom Connectors lesson plan discusses weather conditions and their contribution to weathering and erosion. Students learn to explain the process of physical and chemical weathering. They also learn to compare and contrast erosion resulting from wind, ice and water. The site provides goals, objectives, an outline, time required, materials, activities, and closure ideas for the lesson. The Classroom Connectors address content with an activity approach while incorporating themes necessary to raise the activity to a higher cognition level. The major motivation is to employ instructional strategies that bring the students physically and mentally into touch with the science they are studying.

322

WeatherTracker  

NSDL National Science Digital Library

WeatherTracker is the ideal desktop application for anyone who always wants to know what the weather outside is like. The temperature, barometric pressure, humidity, winds, and current conditions can be displayed in three different formats, updated hourly for North American Cities. The local forecasts, climate data and near shore marine forecasts can be displayed in other windows and are available for select North American cities. Other cities are limited to temperature and current conditions. WeatherTracker is shareware with a fee of $20.00.

323

Wonderful World of Weather  

NSDL National Science Digital Library

This website uses real time data for many activities for learning about the weather. It can be modified to fit virtually any grade level. The project is broken up into 3 sets of lessons; Introductory Activities, Real Time Data Activities, and Language Arts Activities. Each lesson gives a recommended time for completion, to help keep students and teachers on track. There is a helpful teachers guide section with background information about real time data, curriculum standards, and assessment suggestions. Th students gallery has many examples of real projects other students have already created. There is also a helpful reference guide, with information on real time weather, projects, and weather lesson plans.

2006-01-01

324

Space Weather Now  

NSDL National Science Digital Library

The NOAA Space Weather Now website provides non-technical information and an assortment of images detailing current space weather. Visitors can find summaries describing auroras, plots of current auroral ovals on the poles, and viewing information for the Northern and Southern Hemispheres. The Real-Time Solar Wind Pages furnish dynamic plots of data, geomagnetic activity test product information, and resources about the four instruments used to collect data on geomagnetic storms. The website features Space Weather Scales to help the public understand the severity of environmental disturbances due to geomagnetic storms, solar radiation storms, and radio blackouts. Visitors can find the latest news, alerts, advisory bulletins, and much more.

325

Frost weathering: Climate control of regolith production and critical zone evolution  

NASA Astrophysics Data System (ADS)

Rock generally displays greater fracture density and reduced strength near the surface than at depth. Relatively few processes can explain this profile of mechanical damage seen in rock. Motivated by weathered rock profiles measured in Gordon Gulch in the Boulder Creek Critical Zone Observatory (Colorado Front Range, USA), we focus on frost cracking as an important weathering process. We use our measurements to guide a model of frost cracking. Although the modern mean annual ground temperature is ~4°C, it was subzero during Pleistocene glacial times. Frost cracking is therefore a plausible mechanism of rock damage. Rock on north-facing slopes in this high elevation catchment (~2600 m a.s.l.) is more deeply weathered and displays lower tensile strength than rock on south-facing slopes. We present detailed subsurface temperature profile records at sites on both slopes, reaching depths up to 1.5 m, and therefore crossing the mobile regolith - saprolite interface. We augment existing frost cracking models by incorporating daily thermal cycles, snow cover, latent heat, variation in material properties with depth, and limitations imposed by long transport distances for water to the freezing front. The north- and south-facing hillslope asymmetries in critical zone architecture can be explained with differences in mean annual surface temperatures, although moisture differences may also play a role. A temperature-controlled model of rock weathering enables consideration of the effect of climate change on weathered profile development.

Anderson, S. P.; Anderson, R. S.; Kelly, P. J.; Tucker, G. E.; Wickert, A.

2012-04-01

326

A model of weathering intensity for the Australian continent  

NASA Astrophysics Data System (ADS)

Regolith encompasses all weathered materials in the zone between the Earth's surface and fresh bedrock at depth. This weathered zone includes the soil, which may constitute the whole of the regolith profile or represent only its upper part. Important hydrological and biogeochemical processes operate within the regolith, including the infiltration and storage of near-surface water and nutrients, which sustain agricultural productivity. The degree to which the regolith is weathered (or its weathering intensity) is intrinsically linked to the factors involved in soil formation including parent material, climate, topography, biota and time. The degree to which the bedrock or sediments are weathered has a significant effect on the nature and distribution of regolith materials. There is commonly a strong correlation between weathering intensity and the degree of soil development as well as the depth of the weathering front. Changes in weathering intensity correspond to changes in the geochemical and physical properties of bedrock, ranging from essentially unweathered parent materials through to intensely weathered and leached regolith where all traits of the original protolith (original unweathered rock) are overprinted or lost altogether. With increasing weathering intensity we see mineral and geochemical convergence to more resistant secondary weathered materials including clay, silica, and various oxides. A weathering intensity index (WII) over the Australian continent has been developed at a 100 m resolution using two regression models based on airborne gamma-ray spectrometry imagery and the Shuttle Radar Topography Mission (SRTM) elevation data. Airborne gamma-ray spectrometry measures the concentration of three radioelements -- potassium (K), thorium (Th) and uranium (U) at the Earth's surface. The total gamma-ray flux (dose) is also calculated based on the weighted additions of the three radioelements. In general K is leached with increasing weathering whereas Th and U typically show increases due to their association in clays and oxides in the profile. These geochemical relationships underpin the first model prediction. In the case where no gamma-ray data is available or where the bedrock is very low in radioelements (e.g. basalt, quartz-rich sandstone) surface relief is used as surrogate in the second prediction model. The two models are combined to generate a weathering intensity index of the Australian continent. The weathering intensity index has been developed for erosional landscapes but also provides useful information on deposition processes and materials. The weathering intensity prediction is evaluated with surface geochemistry (compared with geochemical indices) and previous regolith-landform mapping. The use of the weathering intensity index in natural resource management and mineral exploration is discussed.

Wilford, J.

2013-12-01

327

Rocks and Minerals  

NSDL National Science Digital Library

This web page offers a simple illustrated guide to the three rock types- igneous, sedimentary, and metamorphic; and the most common rock-forming mineral groups: quartz, plagioclase feldspars, potassium feldspars, micas, amphiboles, olivine, and calcite. The rock types include extrusive and intrusive igneous rocks, clastic, biologic, and chemical sedimentary rocks, and both foliated and non-foliated metamorphic rocks. A section is included on naming igneous rocks. The igneous rocks tuff and basalt are also discussed, as is sediment. Users are directed to related resources and may print out a simplified rock classification chart.

328

External Resource: Rock Cycle Animation  

NSDL National Science Digital Library

This cutaway view of Earth shows where some common rock-forming processes occur. Embedded animations will illustrate the path of a rock moving through the rock cycle. Topics include: rock cycle, magma chamber, magma, igneous rock, sedimentary rock, erosio

1900-01-01

329

Weathering in a Cup.  

ERIC Educational Resources Information Center

Two easy student activities that demonstrate physical weathering by expansion are described. The first demonstrates ice wedging and the second root wedging. A list of the needed materials, procedure, and observations are included. (KR)

Stadum, Carol J.

1991-01-01

330

Weathering of Martian Evaporites  

NASA Technical Reports Server (NTRS)

Evaporites in martian meteorites contain weathering or alteration features that may provide clues about the martian near-surface environment over time. Additional information is contained in the original extended abstract.

Wentworth, S. J.; Velbel, M. A.; Thomas-Keprta, K. L.; Longazo, T. G.; McKay, D. S.

2001-01-01

331

Tombstone Weathering Lab  

NSDL National Science Digital Library

Students work in groups in a cemetery to collect a quantitative and a qualitative measure of the extent of weathering of tombstones and their ages. The data are shared between all students, graphed as scatter plots, and the rate of weathering is estimated. Students write about and then discuss the results, the difference between the quantitative and qualitative measures, and speculate on factors in addition to time that may be important for weathering rate. The exercise ends with each students writing a hypothesis about a factor that influences weathering rate and describing a research project that could test that hypothesis. This activity is aimed at developing an understanding of the scatter in "real data", allowing for practice of team work, and hypothesis generation and testing. Designed for a geomorphology course Has minimal/no quantitative component

Anders, Alison

332

Weather Information Processing  

NASA Technical Reports Server (NTRS)

Science Communications International (SCI), formerly General Science Corporation, has developed several commercial products based upon experience acquired as a NASA Contractor. Among them are METPRO, a meteorological data acquisition and processing system, which has been widely used, RISKPRO, an environmental assessment system, and MAPPRO, a geographic information system. METPRO software is used to collect weather data from satellites, ground-based observation systems and radio weather broadcasts to generate weather maps, enabling potential disaster areas to receive advance warning. GSC's initial work for NASA Goddard Space Flight Center resulted in METPAK, a weather satellite data analysis system. METPAK led to the commercial METPRO system. The company also provides data to other government agencies, U.S. embassies and foreign countries.

1991-01-01

333

Microbial Weathering of Olivine  

NASA Astrophysics Data System (ADS)

Controlled microbial weathering of olivine experiments displays a unique style of nanoetching caused by biofilm attachment to mineral surfaces. We are investigating whether the morphology of biotic nanoetching can be used as a biosignature.

Longazo, T. G.; Wentworth, S. J.; Southam, G.; McKay, D. S.

2002-03-01

334

Weather and Climate.  

National Technical Information Service (NTIS)

Recommendations for using space observations of weather and climate to aid in solving earth based problems are given. Special attention was given to: (1) extending useful forecasting capability of space systems, (2) reducing social, economic, and human lo...

1975-01-01

335

Winter Weather: Outdoor Safety  

MedlinePLUS

... During a Wildfire Responders Wildfire Smoke After a Fire Worker Safety During Fire Cleanup Wildfires PSAs Related Links Winter Weather Extreme ... a two-wave radio, waterproof matches and paraffin fire starters with you. Do not use alcohol and ...

336

Winter Weather: Hypothermia  

MedlinePLUS

... During a Wildfire Responders Wildfire Smoke After a Fire Worker Safety During Fire Cleanup Wildfires PSAs Related Links Winter Weather Extreme ... at Disaster Sites Preventing Chain Saw Injuries During Tree Removal Electrical Safety and Generators Handling Human Remains ...

337

Winter Weather: Indoor Safety  

MedlinePLUS

... During a Wildfire Responders Wildfire Smoke After a Fire Worker Safety During Fire Cleanup Wildfires PSAs Related Links Winter Weather Extreme ... 3 feet of anything that may catch on fire, such as drapes, furniture, or bedding. Never cover ...

338

Palmer Automatic Weather Station  

NSF Publications Database

... EAM NSF Org: OD / OPP Date : December 06, 1991 File : opp93040 DIVISION OF POLAR PROGRAMS OFFICE OF ... Palmer Automatic Weather Station) To: Files (S.7 - Environment) This Environmental Action Memorandum ...

339

Cold-Weather Sports  

MedlinePLUS

Ahh, winter! Shorter days. Frigid temperatures. Foul weather. What better time to be outdoors? Winter sports can help you burn calories, increase your cardiovascular fitness, and strengthen muscles. Activities that are ...

340

Wonderful World of Weather  

NSDL National Science Digital Library

This standards-based unit has been created for use by students in the elementary grades to investigate weather phenomena both locally as well as in other places around the world. By using hands-on activities and real-time data investigations, students develop a basic understanding of how weather can be described in measurable quantities. The lesson plans have been designed to allow teachers to select the ones which fit into their curriculum, and to allow for flexibility in implementation.

2011-01-01

341

Weather Here and There  

NSDL National Science Digital Library

The Global Education Project of the Resource for Science Education Program offers the Weather Here and There educational unit. The Web site consists of six lessons geared for students in grades four through six that cover everything from characteristics of the Earth's atmosphere to forecasting the weather. Each lesson contains the objectives, materials, background information, vocabulary, evaluation, etc. needed to easily prepare and complete each.

1995-01-01

342

TypoWeather  

NSDL National Science Digital Library

The TypoWeather application is a great way to stay on top of the latest weather conditions. This handy device presents users with a five day outlook and an hourly breakdown that is updated based on data from the National Meteorological Service. Visitors can customize their layout to include alerts about certain meteorological conditions, such as wind patterns, humidity, and more. This version is compatible with all operating systems.

2014-03-13

343

Google Earth Weather Bundle  

NSDL National Science Digital Library

The Google Earth Weather Bundle, from the Department of Atmospheric Sciences at the University of Illinois, gives the user a suite of automatically updating weather products that can be overlaid in any fashion he or she desires. It can be downloaded from the department's web site at the University of Illinois, and is meant for worldwide use by a wide range of audiences, from the general public to meteorologists.

344

Weathering and Erosion  

NSDL National Science Digital Library

In this multi-station lab, learners conduct a series of experiments to explore the processes and effects of weathering and erosion. Using the results from these explorations, learners design and conduct an experiment comparing the rate of erosion in different biomes. Use this activity to teach weathering and erosion, and also to illustrate how scientists often use the results of one experiment to inspire another. This activity is intended to be conducted over multiple meetings.

Whitfield, Lise

2010-01-01

345

Weathering of granodioritic crust, long-term storage of elements in weathering profiles, and petrogenesis of siliciclastic sediments  

NASA Astrophysics Data System (ADS)

The bulk composition and mineralogy of the Toorongo Granodiorite, Australia, are similar to average upper continental crust (AUCC). Weathering characteristics of the Toorongo profile consequently provide insight into large-scale chemical weathering of the upper crust. In situ weathered materials of the profile do not reflect parent granodiorite composition in quartz-plagioclase-K-feldspar (Q-P-K) or in quartz-feldspar-rock fragment (Q-F-L) compositional space. Intensive in situ weathering precludes sands, derived from mature weathering profiles through erosion, from reflecting their provenance. Where intensive chemical weathering has occurred, clay minerals and oxyhydroxides of the profile, and by inference muds derived therefrom, contain much more chemical information about provenance than do associated sands. Actinides, rare earth elements (REEs), many transition metals, and metalloids have accumulated in deep parts of the weathering profile at concentrations much greater than observed in the fresh granodiorite. Mass balance considerations require the bulk of these elements to have been derived from previously weathered, and now eroded, granodiorite. These elements were, and are, continually cycled from the intensely weathered uppermost soil zone to deeper, less weathered, zones of the profile where they accumulate. The profile therefore represents a large, continental elemental storage reservoir, the storage capacity of which has increased over time. Wherever erosion is sufficiently slow and chemical weathering sufficiently rapid, mature weathering profiles may become large, long-term storage reservoirs for actinides, REEs, and many other elements. The total REE contents of extremely weathered soil material are somewhat less than in the parent granodiorite, but they are enriched twofold to threefold in the zone of intermediate weathering relative to parent. Similar variations in total REEs are observed in some muds when normalized to their source (AUCC). These differences are attributed to a combination of chemical weathering and selective mass wasting of profiles. Homogenization of detritus in large sedimentary basins, however, produces muds with REE patterns and total REE contents similar to source (AUCC). Nd/Sm ratios are not influenced by chemical weathering, although both elements are mobilized by weathering and become enriched by over 200% relative to parent rock. Constancy of Nd/Sm in the profile indicates that Nd-Sm model ages derived from soils and sediments are not affected by chemical weathering. The least mobile trace elements of the profile are Sc, Cu, Nb, and Ta, but others are more mobile. Thorium, for example, is mobilized during weathering of the Toorongo Granodiorite and displays a twofold increase in the profile, as does the Th/Sc ratio. The ratio, however, varies by more than a hundredfold in major rock types so that Th/Sc (and other ratios) provides valuable information about provenance, although sensitivity is diminished somewhat by the effects of chemical weathering.

Nesbitt, H. Wayne; Markovics, G.

1997-04-01

346

Utility weatherization programs  

SciTech Connect

Public utility commissions (PUCs) have recently ordered or approved an increasing number of programs that install weatherization measures in residences. These programs tend to install only low-cost weatherization measures (e.g., caulking, weatherstripping, plastic storm windows, door sweeps) or major weatherization measures (e.g., insulation, storm windows, storm doors). When a program does not have income restrictions for eligibility, part of the costs are paid by the participating customer. For programs that install low-cost measures, the participant usually pays at the time of installation for the measures chosen. To require payment for major weatherization measures at the time of installation could deter participation, so these programs usually provide loans with the interest subsidized by the sponsor. Low-income customers, who have little or no disposable income, tend to shun Residential Conservation Service, loan, and other utility conservation programs that have costs to participants. Therefore PUCs have turned to programs that install weatherization measures without charge in order to reach low-income customers. This paper discusses some of the regulatory issues raised by these programs and how they have been justified by PUCs. It also gives information on cost and energy savings for 10 weatherization programs, both utility-sponsored and non-utility-sponsored, and attempts to interpret this information.

Kier, P.H.

1984-01-01

347

Cockpit weather information system  

NASA Technical Reports Server (NTRS)

Weather information, periodically collected from throughout a global region, is periodically assimilated and compiled at a central source and sent via a high speed data link to a satellite communication service, such as COMSAT. That communication service converts the compiled weather information to GSDB format, and transmits the GSDB encoded information to an orbiting broadcast satellite, INMARSAT, transmitting the information at a data rate of no less than 10.5 kilobits per second. The INMARSAT satellite receives that data over its P-channel and rebroadcasts the GDSB encoded weather information, in the microwave L-band, throughout the global region at a rate of no less than 10.5 KB/S. The transmission is received aboard an aircraft by means of an onboard SATCOM receiver and the output is furnished to a weather information processor. A touch sensitive liquid crystal panel display allows the pilot to select the weather function by touching a predefined icon overlain on the display's surface and in response a color graphic display of the weather is displayed for the pilot.

Tu, Jeffrey Chen-Yu (Inventor)

2000-01-01

348

Chemical Weathering in the Amur River  

NASA Astrophysics Data System (ADS)

The Amur River is the fourth largest river (~1,855,000 km2) in north Eurasia which flow into the Pacific Ocean. It flows through 4 countries-the Russian Far East, northeast China, east Mongolia and a small territory of North Korea. Climatic and ecological conditions differ significantly from western intercontinental region to eastern coastal area. Southern part of the Amur basin is mostly lowland region with alluvial deposits and various rocks of sedimentary and magmatic origin. In the northern part, there are mountains with siliceous and carbonaceous sedimentary rocks, and permafrost plays an important role in river chemical discharge. We examined dissolved major element and Sr isotopic compositions of 19 summer samples in the middle reach of the Amur to better understand the relationship between chemical weathering, geology, and climate (with the aid of GlS). We found that the 87Sr/86Sr ratios fall a narrow the range of 0.709-0.712 and the TDS (total dissolved solids) is about 80 (40-180) mg/L. Kaolinite is the thermodynamically stable silicate mineral for most samples. We quantified chemical weathering rates using an inverse model: rain accounts for (2-14)% of the total cationic concentration, evaporites (3-19)%, carbonates (43-77)%, and silicates (14-32)%. Net CO2 consumption rate by silicate weathering in the Amur basin is in the range of (10-100) ×103 mol/km2/yr, and the value at the main channel above confluence with the Sungari tributary is ~10 ×103 mol/km2/yr. We tested correlations between the CO2 consumption rates by silicate weathering and various climatic (air temperature, precipitation, and runoff) and geologic (relief, slope, elevation) factors calculated using GIS. Stepwise regression using SPSS on the entire data set yielded best correlation (negative) with elevation (R2 = 0.6823, p = 0.0002).

Moon, S.; Huh, Y.

2006-12-01

349

Major Rock Groups  

NSDL National Science Digital Library

This resource from the University of Saskatchewan contains general information on the major rock groups: igneous, metamorphic and sedimentary. Describes the rock cycle and the properties and formation of each major rock group.

2008-08-21

350

New Rock Physical Properties Assessments From the Mars Exploration Rover Rock Abrasion Tool (RAT).  

NASA Astrophysics Data System (ADS)

The Rock Abrasion Tool (RAT) serves as the sample preparation device on the Mars Exploration Rovers (MER) science payload. The RAT grinds a circular area 45 millimeter in diameter, and on the order of a few millimeters deep, into a rock face. This process removes surface fines and weathered layers in preparation for imaging and spectral observations of the rock. As of September 2005, 15 grinding operations have been performed at Gusev Crater and 26 at Meridiani Planum. Since the RAT performs a mechanical operation on a rock, deductions can be made via the RAT's engineering data about the rock's physical properties. For each grinding operation, the energy consumed while grinding is converted to provide a physically relevant Specific Grind Energy (SGE) in terms of Joules per cubic millimeter of rock removed. The calculation is performed over the last 0.25 millimeter of a grinding operation, where it is possible, by taking measurements from Microscopic Imager images of the abraded area, to make an accurate estimate of the volume of rock removed. Progress is presented on recent refinement of the SGE calculation methods including decoupling of artifacts. Environmental factors and differing parameters used to command the RAT operations are among the key artifacts recently analyzed. Progress is also presented on further characterization of the dynamics and wear mechanics involved in the grinding process, and how they influence SGE. A library of Earth rocks has been assembled and it is being used with the RAT Engineering Model to create a set of similar SGE data products that can be compared to Mars rocks in order to contribute to physical properties assessments of the Mars rocks. Initial results indicate that the Martian rocks are analogous to a range of Earth rocks, from gypsum to low-strength basalt in terms of grindability; however, caution needs to be exercised in making a direct comparison of grinding energies. This is because the grindability of rocks was found to be a function not only of rock properties (such as the degree of weathering, mineral composition, and grain sizes) but also of the environmental conditions and other factors. Nevertheless, the SGE deduced from the RAT engineering data, and linked with data from other instruments in the payload, represent the most comprehensive database yet created of the physical properties of Martian rocks and are therefore of great value to our understanding of the geologic history of Mars and future instrument design for forthcoming Mars missions.

Bartlett, P. W.; Basso, B.; Kusack, A.; Wilson, J.; Zacny, K.

2005-12-01

351

Oldest and Largest Weather, p. 2  

E-print Network

spared news, p. 6­7 dr. dOg rOCkS BOStON The Philly band makes performances delightfully personal arts, pMIT's Oldest and Largest Newspaper Weather, p. 2 Volume 131, Number 10 tech.mit.edu Friday, March 4, 2011 FrI: 32°f | 28°f Partly Cloudy Sat: 47°f | 41°f Cloudy SUN: 50°f | 36°f Rain SeCtIONS World

352

Social Aspects of Weather Modification  

Microsoft Academic Search

A description of the social context and citizen response to three weather modification projects provides an introduction to the discussion of a variety of social and economic issues related to planned weather modification. Various interest groups have markedly different perspectives on weather modification. Most persons subject to the consequences of weather modification have no opportunity to participate in the associated

J. Eugene Haas

1973-01-01

353

2012 Severe Weather Awareness Guide  

E-print Network

Florida's 2012 Severe Weather Awareness Guide 2012 Severe Weather Awareness Guide F L O R I D A D I of Emergency Management #12;Florida's Severe Weather Awareness Guide 2 Florida is affected by many natural. That is why I am proud to present the 2012 Severe Weather Awareness Guide. By reading this guide you can learn

Meyers, Steven D.

354

Collecting and Identifying Rocks  

NSDL National Science Digital Library

In this Earth Science activity, students will investigate rocks in an outdoor field trip. Students will be divided into groups and given a Ziploc bag to collect rocks. We will then return to the classroom, and the students will put their rocks into different groups. The different groups could be the size, shape, color, and texture of the rocks. We will then talk about the Rock Cycle and the three main types of rocks. Students will record their observations in their science journals.

Linda Harvey, Marquette Catholic School, Virginia,MN

355

Rocks are fun  

NSDL National Science Digital Library

Rocks are the most common material on earth. We will learn about the parts that make up the rocks and sort rocks based upon color, hardness, texture, layering, and particle size. Click on each of the links below to learn about the main types of rocks and then answer the questions that follow. *Igneous Rocks 1. In your own words, explain the TWO ways in which an igneous rock can be formed. 2. Please illustrate ONE of the ways an igneous rock is formed. *Metamorphic Rocks 1. Why ...

Peterson, Lori

2009-12-14

356

S-290 Unit 9: Observing the Weather  

NSDL National Science Digital Library

This webcast covers procedures for taking accurate weather observations using belt weather kits and descriptions of other common weather observing equipment used in fire weather. In addition, maintenance of the primary components of the belt weather kit are demonstrated.

Comet

2009-04-22

357

The Influence of Weathering on the Engineering Properties of Dunites  

NASA Astrophysics Data System (ADS)

Weathering processes cause important changes in the engineering properties of rocks. In this study, dunites in the Bursa region in western Turkey were investigated and the changes in engineering properties due to weathering were evaluated. The studies were initiated with field observations including measurement of the characteristics of discontinuities such as spacing, aperture, fill material, roughness, and Schmidt hammer rebound value. Subsequently, laboratory studies were conducted in two stages. The first stage comprised mineralogical, petrographic, and chemical analyses. The second stage included physicomechanical tests to determine specific gravity, unit weights, water absorption, effective porosity, uniaxial compressive strength, P-wave velocity, and slake-durability index. According to these evaluations, the changes in engineering properties were determined to be mostly related to serpentinization at every stage of weathering. The most suitable parameters for characterizing the degree of weathering of the studied dunites are loss-on-ignition values, specific gravity, unit weight, water absorption, and effective porosity.

Ündül, Ömer; Tu?rul, Atiye

2012-03-01

358

Myocardial infarction and weather.  

PubMed

The association of meterological factors with acute myocardial infarction was studied within a one-year period in Helsinki. Seasonal variation was found with the lowest incidence in summer and the highest in late autumn. Environmental temperature was not significantly correlated with the incidence of myocardial infarction but the case fatality rate was higher on coldest days. Atmospheric pressure turned out to be the meteorological variable with the highest correlation with the occurrence of myocardial infarction. Rapid decrease in atmospheric pressure was also associated with increased incidence of acute myocardial infarction. Relative humidity had little independent effect. The weather types with highest and lowest risk of heart attack were determined by the combined use of factor and cluster analysis. The most unfavourable turned out to be a relatively cold and moist weather with low atmospheric pressure, common in Helsinki during early winter and late autumn. The incidence of infarction did not increase on typical cold and dry winter days. The most favourable weather was warm, dry and stable summer weather. The difference in incidences between most and least favourable weather types was three-fold. PMID:616207

Sarna, S; Romo, M; Siltanen, P

1977-08-01

359

Weather from the Stratosphere?  

NASA Technical Reports Server (NTRS)

Is the stratosphere, the atmospheric layer between about 10 and 50 km, important for predicting changes in weather and climate? The traditional view is that the stratosphere is a passive recipient of energy and waves from weather systems in the underlying troposphere, but recent evidence suggests otherwise. At a workshop in Whistler, British Columbia (1), scientists met to discuss how the stratosphere responds to forcing from below, initiating feedback processes that in turn alter weather patterns in the troposphere. The lowest layer of the atmosphere, the troposphere, is highly dynamic and rich in water vapor, clouds, and weather. The stratosphere above it is less dense and less turbulent (see the figure). Variability in the stratosphere is dominated by hemispheric-scale changes in airflow on time scales of a week to several months. Occasionally, however, stratospheric air flow changes dramatically within just a day or two, with large-scale jumps in temperature of 20 K or more. The troposphere influences the stratosphere mainly through atmospheric waves that propagate upward. Recent evidence shows that the stratosphere organizes this chaotic wave forcing from below to create long-lived changes in the stratospheric circulation. These stratospheric changes can feed back to affect weather and climate in the troposphere.

Baldwin, Mark P.; Thompson, David W. J.; Shuckburgh, Emily F.; Norton, Warwick A.; Gillett, Nathan P.

2006-01-01

360

Oceans, Climate, and Weather  

NSDL National Science Digital Library

This resource guide from the Middle School Portal 2 project, written specifically for teachers, provides links to exemplary resources including background information, lessons, career information, and related national science education standards. What is the difference between weather and climate? What do the oceans have to do with them? Weather is the day-to-day state of the atmosphere and its short-term (minutes to weeks) variation. Climate is typically described by the regional patterns of seasonal temperature and precipitation over 30 years. The averages of annual temperature, rainfall, cloud cover, and depth of frost penetration are all typical climate-related statistics. The oceans influence the worlds climate by storing solar energy and distributing it around the planet through currents and atmospheric winds.This publication is all about developing your students understandings of earths oceans and the major effect they have on climate. Understanding and interpreting local weather data and understanding the relationship between weather and climate are important first steps to understanding larger-scale global climate changes. Activities that ask students to collect and analyze local weather data as well as analyze global data can be found in the Lessons and Activities section. Analyzing and interpreting data is a major focus of this publication. Numerous data sets can be found in the Sources for Real Data section. The Background Information section and the article Tomorrows Forecast will help reinforce your own content knowledge.

Lightle, Kimberly

2006-10-01

361

Spaceborne weather radar  

NASA Technical Reports Server (NTRS)

The present work on the development status of spaceborne weather radar systems and services discusses radar instrument complementarities, the current forms of equations for the characterization of such aspects of weather radar performance as surface and mirror-image returns, polarimetry, and Doppler considerations, and such essential factors in spaceborne weather radar design as frequency selection, scanning modes, and the application of SAR to rain detection. Attention is then given to radar signal absorption by the various atmospheric gases, rain drop size distribution and wind velocity determinations, and the characteristics of clouds, as well as the range of available estimation methods for backscattering, single- and dual-wavelength attenuation, and polarimetric and climatological characteristics.

Meneghini, Robert; Kozu, Toshiaki

1990-01-01

362

Predicting Seasonal Weather  

NSDL National Science Digital Library

Recently, the National Science Foundation has developed a number of Flash-enabled features that showcase the latest research done under their general direction. Many of these features deal directly with a host of pragmatic issues, and some are quite delightful in their overall execution and visual appeal. One such feature highlighted on this site deals with predicting seasonal weather. Of course, predicting such trends in weather are both important to the general public, and to those businesses that are sensitive to the weather conditions. In a series of brief essays, replete with illustrative diagrams, visitors can learn about a new proposed seasonal forecast model. The site is rounded out by a link to a number of classroom resources, thematically organized for convenience.

2005-01-01

363

Jet Streams and Weather  

NSDL National Science Digital Library

In this lesson, students learn about jet streams and explore the effects the polar-front jet stream has on weather conditions in North America. They begin by doing an interactive activity that highlights the atmospheric conditions and phenomena that create jet streams. They then look at a model that illustrates the relationships between latitude and variations in air temperature, wind speed, and altitude and begin to make generalizations about these relationships. In the second part of this lesson, they use the knowledge gained in the first part to interpret weather maps, helping them to make direct connections between the behavior of the polar-front jet stream and seasonal weather patterns in North America. As a final exercise, they will use real data to deepen their understanding of the relationships between pressure, altitude, and the wind speed of jet streams.

2005-01-01

364

New weather radar coming  

NASA Astrophysics Data System (ADS)

What would you call the next generation of radar for severe weather prediction? NEXRAD, of course. A prototype for the new system was recently completed in Norman, Okla., and by the early 1990s up to 195 stations around the United States will be tracking dangerous weather and sending faster, more accurate, and more detailed warnings to the public.NEXRAD is being built for the Departments of Commerce, Transportation, and Defense by the Unisys Corporation under a $450 million contract signed in December 1987. Th e system will be used by the National Weather Service, the Federal Aviation Administration (FAA), and the U.S. Air Force and Navy. The NEXRAD radar tower in Norman is expected to be operational in October.

Maggs, William Ward

365

Delicious Differential Weathering  

NSDL National Science Digital Library

Students are asked to place a Baby Ruth candy bar in their mouths but are asked not to bite it. Once they have sucked off all the chocolate and caramel the students are given permission to bite the peanuts. After lecturing on the differences between chemical and physical weathering students are asked to list the order of ingredients they tasted. Each group is given a sample of granite. Students are asked to list three visible minerals in the granite. Relate the minerals of the granite (hornblende, feldspar, and quartz) to the ingredients of the candy bar. Explain Bowen's reaction series and how different minerals will weather first and how climate will affect weathering rates.

Gorte, Mary

366

Weather Scope : An Investigative Study of Weather and Climate  

NSDL National Science Digital Library

During the course of this project, students will learn how to build instruments to measure weather, access online weather observations, collect weather data for an extended period, analyze weather data to reveal trends, and make predictions. They will develop a basic understanding of how weather can be described in measurable quantities such as temperature, wind and precipitation. The module contains five lessons relating to weather, five relating to climate, and three enrichment activities. Project information, a teacher guide, reference materials, and an ask an expert feature are also provided.

2007-12-12

367

Wonderful World of Weather  

NSDL National Science Digital Library

This standards-based module uses hands-on activities and real-time data investigations to allow students in the elementary grades to investigate weather phenomena both locally as well as in other places around the world. By using hands-on activities and real-time data investigations, the students will develop a basic understanding of how weather can be described in measurable quantities, such as temperature, wind and precipitation. The lesson plans which make up this module have been designed to allow teachers to select the ones which fit into their curriculum to allow for flexibility in implementation

2003-01-01

368

Weather and Health  

NSDL National Science Digital Library

This course will help meteorologists and others broaden their understanding of the impacts of weather and climate on public health, including the impacts of heat waves and cold temperatures, winter storms and thunderstorms, flooding, drought, poor air quality, tornadoes, hurricanes, wildfire, UV radiation, and others. This course is directed to broadcast meteorologists, in particular, who play a critical role in the community by helping the public to protect against weather-related health threats and by promoting good health. The course also describes the public health communication system, providing information about reliable public health services, tools, and resources.

Comet

2008-11-25

369

Olympian weather forecasting  

NASA Astrophysics Data System (ADS)

A unique public-private partnership will provide detailed weather information at the 2002 Winter Olympics in Utah, 8-24 February About 50 meteorologists with the National Weather Service (NWS) and several private groups will work in the background to provide accurate forecasts.This is the first time that U.S. government and private meteorologists will share forecasting responsibilities for the Olympics, according to the Salt Lake Organizing Committee for the Olympic Games. The partnership includes meteorologists with the University of Utah and KSL-TV in Salt Lake City.

Showstack, Randy

370

Weather and Climate  

NSDL National Science Digital Library

This background chapter reviews the basic principles of meteorology that educators need to guide inquiry activities in the classroom. Topics include structure of the atmosphere, Coriolis effect, water cycle, greenhouse effect, cyclones, anticyclones, and jet streams. This is chapter 2 of Meteorology: An Educator's Resource for Inquiry-Based Learning for Grades 5-9. The guide includes a discussion of learning science, the use of inquiry in the classroom, instructions for making simple weather instruments, and more than 20 weather investigations ranging from teacher-centered to guided and open inquiry investigations.

371

Effects of climate on chemical weathering in watersheds  

USGS Publications Warehouse

Climatic effects on chemical weathering are evaluated by correlating variations in solute concentrations and fluxes with temperature, precipitation, runoff, and evapotranspiration (ET) for a worldwide distribution of sixty-eight watersheds underlain by granitoid rock types. Stream solute concentrations are strongly correlated with proportional ET loss, and evaporative concentration makes stream solute concentrations an inapprorpiate surrogate for chemical weathering. Chemical fluxes are unaffected by ET, and SiO2 and Na weathering fluxes exhibit systematic increases with precipitation, runoff, and temperature. However, warm and wet watersheds produce anomalously rapid weathering rates. A proposed model that provides an improved prediction of weathering rates over climatic extremes is the product of linear precipitation and Arrhenius temperature functions. The resulting apparent activation energies based on SiO2 and Na fluxes are 59.4 and 62.5 kJ.mol-1, respectively. The coupling between temperature and precipitation emphasizes the importance of tropical regions in global silicate weathering fluxes, and suggests it is not representative to use continental averages for temperature and precipitation in the weathering rate functions of global carbon cycling and climatic change models. Fluxes of K, Ca, and Mg exhibit no climatic correlation, implying that other processes, such as ion exchange, nutrient cycling, and variations in lithology, obscure any climatic signal. -from Authors

White, A. F.; Blum, A. E.

1995-01-01

372

Astrobiological Implications of Rock Varnish in Tibet  

NASA Astrophysics Data System (ADS)

The study of terrestrial geomicrobiology and its relationship to rock weathering processes is an essential tool in developing analogues for similar processes that may have occurred on Mars. Most studies of manganese-enhanced rock varnish have focused on samples taken from warm arid desert regions. Here, we examine samples obtained from eolian-abraded lava flows of the 4700-4800 m high Ashikule Basin in Tibet. Because it receives approximately 300 mm of precipitation annually, this site is nowhere near as dry as Atacama Desert locales. However, the dusty, sulfate-rich, high-altitude and high-UV flux environment of the Tibetan locale offers new insight into rock varnish formation processes in a terrestrial environment that displays some attributes similar to those expected on early Mars. Microprobe measurements reveal that Mn enhancements in varnish are two orders of magnitude above the dust source, but Fe is only enhanced by a factor of three. Manganese-enhancing bacterial forms are not abundant but are still approximately 3 times more common than in Mojave and Sonoran Desert varnishes. In addition to its occurrence in subaerial positions, Tibetan varnish also occurs in micron-scale "pods" enveloped by silica glaze and as remobilized constituents that have migrated into the underlying weathering rind. A lack of surficial Mn-rich varnish, therefore, might not imply the absence of varnish. In contrast to suggestions that silica glaze might be a good source of microbial fossils and a key to varnish formation, we did not observe any clear microfossil forms entombed in silica glaze; further, there is no gradation between varnish and silica glaze but only distinct contacts. %K Analogue, Astrobiology, Bacteria, Biomineralization, Desert varnish, Geomicrobiology, Life on Mars, Manganese enhancement, Rock coating, Rock varnish, Microstromatolite, Tibet, Weathering

Krinsley, David; Dorn, Ronald I.; DiGregorio, Barry

2009-08-01

373

Sed Rocks Self-Instruction Lab Name Geology 100 Harbor Section  

E-print Network

. Sedimentary rocks are usually identified in the field by their stratification or layering, which usually by the precipitation of minerals directly from water. In the Great Salt Lake of Utah, sodium (Na+) weathered from

Harbor, David

374

Everybody Find a Rock  

NSDL National Science Digital Library

In this lesson, younger students will learn to recognize the properties of selected rocks. After participating in a read-aloud, the students will examine a variety of polished rocks, and take a walk outside to find their own rocks. As a closure activity, they are directed to explore other unique rocks at home and bring them in for class discussion and sorting.

375

Evidence of frost-cracking inferred from acoustic emissions in a high-alpine rock-wall  

E-print Network

Evidence of frost-cracking inferred from acoustic emissions in a high-alpine rock-wall D. Amitranoa within rock is known to be an important driver of near-surface frost weathering as well as of rock damage, elastic interaction and poro-mechanics in order to describe freezing-related stresses. Keywords: frost

Paris-Sud XI, Université de

376

Estimating rock mass properties using Monte Carlo simulation: Ankara andesites  

NASA Astrophysics Data System (ADS)

In the paper, a previously introduced method ( Sari, 2009) is applied to the problem of estimating the rock mass properties of Ankara andesites. For this purpose, appropriate closed form (parametric) distributions are described for intact rock and discontinuity parameters of the Ankara andesites at three distinct weathering grades. Then, these distributions are included as inputs in the Rock Mass Rating ( RMR) classification system prepared in a spreadsheet model. A stochastic analysis is carried out to evaluate the influence of correlations between relevant distributions on the simulated RMR values. The model is also used in Monte Carlo simulations to estimate the possible ranges of the Hoek-Brown strength parameters of the rock under investigation. The proposed approach provides a straightforward and effective assessment of the variability of the rock mass properties. Hence, a wide array of mechanical characteristics can be adequately represented in any preliminary design consideration for a given rock mass.

Sari, Mehmet; Karpuz, Celal; Ayday, Can

2010-07-01

377

What makes a rock?  

NSDL National Science Digital Library

Rocks are the most common material on earth. We will learn about the parts that make up the rocks and sort rocks based upon color, hardness, texture, layering, and particle size. Lets review: What do you already know about rocks? Please write down your thoughts on a piece of paper. Now, click on the link below to find out what the definition of a rock is. *Intro to Rocks Please answer the questions below in complete sentences on your paper. 1. Rocks are made up of several particles. ...

Christen

2010-06-21

378

All About Rocks  

NSDL National Science Digital Library

Rocks are the most common material on earth. We will learn about the parts that make up the rocks and sort rocks based upon color, hardness, texture, layering, and particle size. Lets review: What do you already know about rocks? Please write down your thoughts on a piece of paper. Now, click on the link below to find out what the definition of a rock is. *Intro to Rocks Please answer the questions below in complete sentences on your paper. 1. Rocks are made up of several particles. ...

Frankovic, Whitney

2009-09-28

379

Rare earth elements in weathering profiles and sediments of Minnesota: Implications for provenance studies  

USGS Publications Warehouse

The relative abundance of rare earth elements in sediments has been suggested as a tool for determining their source rocks. This correlation requires that weathering, erosion, and sedimentation do not alter the REE abundances, or do so in a predictable manner. We find that the rare earth elements are mobilized and fractionated by weathering, and that sediments derived from the weathered materials can display modifications of the original pattern of rare earth elements of some due to grain-size sorting of the weathered material. However, the REE distribution pattern of the provenance terrane can be recognized in the sediments.

Morey, G.B.; Setterholm, D.R.

1997-01-01

380

Fungal attack on rock: solubilization and altered infrared spectra.  

PubMed

Penicillium simplicissimum, isolated from weathering basalt, produced citric acid when grown in a glucose-mineral salts medium with basalt, granite, granodiorite, rhyolite, andesite, peridotite, dunite, or quartzite. After 7 days' growth as much as 31 percent of the silicon, 11 percent of the aluminum, 64 percent of the iron, and 59 percent of the magnesium in some of the rocks were solubilized, and a number of rocks showed altered infrared absorption in the silicon-oxygen vibration region. PMID:17838175

Silverman, M P; Munoz, E F

1970-09-01

381

A Photographic Atlas of Rock Breakdown Features in Geomorphic Environments  

NSDL National Science Digital Library

This downloadable (15 mb) atlas features photos of rocks, rock formations, and landscapes that have been shaped by aeolian (wind), fluvial (river), and other weathering processes. The photos are accompanied by descriptions of the features and discussion of the processes involved in creating them. There is also a discussion of the applicability of these same processes to explain similar features seen on Mars and Venus, and the use of high-resolution imagery from Mars to identify these features. A bibliography is included.

382

Metamorphic Rock Identification  

NSDL National Science Digital Library

In this activity students develop skill in the visual identification of metamorphic rock species and conceptualize the relationships between non-metamorphosed species and their metamorphic counterparts. Students will use a hand lens to examine metamorphic rocks and make observations about grain size, foliation, and other characteristics. Then, using this data, they identify the rocks with the classification sheet included with the student worksheet. They will then match the metamorphic rock with its parent rock.

383

Blogging About the Weather  

NSDL National Science Digital Library

Since the majority of the content standards related to weather focus on forecasting, elementary students often spend a lot of time studying cloud types, fronts, storms, and using a barometer to read air pressure. Although this allows students to "do" scie

Evans, Kyle; Frazier, Wendy

2010-04-01

384

Rainy Weather Science.  

ERIC Educational Resources Information Center

Presents ideas on the use of rainy weather for activities in the earth, life, and physical sciences. Topics include formation and collision of raindrops, amount and distribution of rain, shedding of water by plants, mapping puddles and potholes, rainbow formation, stalking storms online, lightning, and comparing particles in the air before and…

Reynolds, Karen

1996-01-01

385

What Makes the Weather?  

ERIC Educational Resources Information Center

Provides (1) background information showing how the sun, earth, air, and water work together to create weather; (2) six activities on this topic; and (3) a ready-to-copy coloring page on the water cycle. Each activity includes an objective, list of materials needed, recommended age level(s), subject area(s), and instructional strategies. (JN)

NatureScope, 1985

1985-01-01

386

Weather and Flight Testing  

NASA Technical Reports Server (NTRS)

This viewgraph document reviews some of the weather hazards involved with flight testing. Some of the hazards reviewed are: turbulence, icing, thunderstorms and winds and windshear. Maps, pictures, satellite pictures of the meteorological phenomena and graphs are included. Also included are pictures of damaged aircraft.

Wiley, Scott

2007-01-01

387

Weather Stations: Storms  

NSDL National Science Digital Library

In this activity, learners test how cornstarch and glitter in water move when disturbed. Learners compare their observations with videos of Jupiter's and Earth's storm movements. This activity is one station that can be combined with other stations for an hour and half lesson on weather patterns on Jupiter and Earth.

Institute, Lunar A.; Nasa

2011-01-01

388

Space Weather Action Center  

NSDL National Science Digital Library

The Space Weather Action Center is a computer-based activity that allows students to track, from their classroom, the development and progress of solar storms. The activity incorporates online NASA data and addresses national education standards in science, technology and math. Students rotate through four space weather learning stations and are challenged to answer the following questions: Do sunspot regions exist today that could be a source of solar storms?; Have radio signals been recorded today from a flare or coronal mass ejection that could affect Earth?; Has there been a measurable disturbance in the Earth's magnetic field?; and Have auroras been seen within the last 24 hours because of a solar storm? A setup guide is provided to show how to create a Space Weather Action Center in the classroom, including recommendations, diagrams, and the necessary list of materials. The instructional guide features background and evaluation materials, alignments to national standards, extension activities, and instructions on how to read, analyze and record space weather data.

389

Weather or Not?  

NSDL National Science Digital Library

In this problem-based learning activity, teams of students will be asked to forecast the weather up to 48 hours in advance of an outdoor event that is special to them. It may be a local or distant event. The activity is part of Exploring the Environment.

390

Microbial Weathering of Olivine  

NASA Technical Reports Server (NTRS)

Controlled microbial weathering of olivine experiments displays a unique style of nanoetching caused by biofilm attachment to mineral surfaces. We are investigating whether the morphology of biotic nanoetching can be used as a biosignature. Additional information is contained in the original extended abstract.

McKay, D. S.; Longazo, T. G.; Wentworth, S. J.; Southam, G.

2002-01-01

391

Weathering the Double Whammy.  

ERIC Educational Resources Information Center

Discusses how governing boards can help their institutions weather the "double-whammy" of doing more with less: identify the institution's short-term and long-term challenges; refocus the institution's mission, planning, and programming; assess and integrate the institution's tuition, aid, and outreach strategies; redouble the institution's…

Wellman, Jane V.

2002-01-01

392

Dress for the Weather  

NSDL National Science Digital Library

"If someone were traveling to our area for the first time during this time of year, what would you tell them to bring to wear? Why?" This question was used to engage students in a guided-inquiry unit about how climate differs from weather. In this lesson,

Smetana, Lara K.; Glen, Nicole J.

2010-04-01

393

Weather and Agriculture  

NSDL National Science Digital Library

In this lesson plan students will research, discuss, and write reports on the relationship between climate and agriculture. They will pretend that they have just purchased farms in specific parts of the United States and will investigate the weather and climate of that region in order to maximize the chances that their farms will succeed.

394

Pigeons and Weather Warnings  

Microsoft Academic Search

IN the Standard of the 5th instant is an account of a pigeon race from Penzance to London, a distance of 270 miles, which was done by one bird in 5 hours 34 minutes, and by another in 5 hours and 59 minutes. Might not the carrier-pigeon be employed to bring accounts of the weather 300, 400, or even 500

1879-01-01

395

Small-Scale Weather  

NSDL National Science Digital Library

The concepts covered so far that pertain to the Earth's weather will finally be applied in this chapter. A number of basic mechanisms that govern small-scale things such as cloud formation, rain, fog, dew point, and humidity, will be addressed.

Robertson, William C.

2005-01-01

396

Crop Conditions Weather Update  

E-print Network

1 Crop Conditions Weather Update Eastern Flower Thrips on Strawberries Stopping Spread of Apple Scab Fire Blight Strawberry Diseases Chemical thinning Important Grape Sprays Cluster Thinning on Strawberries: High numbers of Eastern Flower Thrips have been reported on late blooming strawberry varieties

Ginzel, Matthew

397

Weather and the Sky  

NSDL National Science Digital Library

This self-contained module on weather and objects in the sky includes a range of fun activities that students can perform in the classroom and at home with family members. They impart important concepts such as observation, identification, measurement, and differentiation.

Science, Houghton M.

398

Accessing Space Weather Information  

NASA Astrophysics Data System (ADS)

To meet the needs of our technology based society, space weather forecasting needs to be advanced and this will entail collaboration amongst research, military and commercial communities to find new ways to understand, characterize, and forecast. In this presentation VITMO, the Virtual Ionosphere-Thermosphere-Mesosphere Observatory will be used as a prototype for a generalized system as a means to bring together a set of tools to access data, models and online collaboration tools to enable rapid progress. VITMO, available at http://vitmo.jhuapl.edu/, currently provides a data access portal for researchers and scientists to enable finding data products as well as access to tools and models. To further the needs of space weather forecasters, the existing VITMO data holdings need to be expanded to provide additional datasets as well as integrating relevant models and model output. VITMO can easily be adapted for the Space Weather domain in its entirety. In this presentation, we will demonstrate how VITMO and the VITMO architecture can be utilized as a prototype in support of integration of Space Weather forecasting tools, models and data.

Morrison, D.; Weiss, M.; Immer, E. A.; Patrone, D.; Potter, M.; Barnes, R. J.; Colclough, C.; Holder, R.

2009-12-01

399

Satellite Weather Watch.  

ERIC Educational Resources Information Center

Describes an inexpensive (about $1,500) direct-readout ground station for use in secondary school science/mathematics programs. Includes suggested activities including, among others, developing map overlays, operating station equipment, interpreting satellite data, developing weather forecasts, and using microcomputers for data storage, orbit…

Summers, R. Joe

1982-01-01

400

METEOROLOGICAL Monthly Weather Review  

E-print Network

AMERICAN METEOROLOGICAL SOCIETY Monthly Weather Review EARLY ONLINE RELEASE This is a preliminary.d.williams@reading.ac.uk #12;2 Abstract In a recent study, Williams (2009) introduced a simple modification to the widely used. In the present paper, the effects of the modification are comprehensively evaluated in the SPEEDY atmospheric

Kalnay, Eugenia

401

Paintball Summer Weather  

E-print Network

Highlights · Paintball · Summer Weather · Birthdays · Manners TheELIWeekly Paintball! Come out and have some fun! This Saturday, September 6th, we are going to play Paintball! Paintball is a popular. The origin of the word "tip" is something that is not 100% certain, but the most common story

Pilyugin, Sergei S.

402

Weather, Climate, and You.  

ERIC Educational Resources Information Center

Information from the American Institute of Medical Climatologists on human responses to weather and climatic conditions, including clouds, winds, humidity, barometric pressure, heat, cold, and other variables that may exert a pervasive impact on health, behavior, disposition, and the level of efficiency with which individuals function is reviewed.…

Blai, Boris, Jr.

403

Dress for the Weather  

ERIC Educational Resources Information Center

"If someone were traveling to our area for the first time during this time of year, what would you tell them to bring to wear? Why?" This question was used to engage students in a guided-inquiry unit about how climate differs from weather. In this lesson, students explored local and national data sets to give "travelers" advice when preparing for…

Glen, Nicole J.; Smetana, Lara K.

2010-01-01

404

Weatherization Works: An interim report of the National Weatherization Evaluation  

SciTech Connect

The National Weatherization Evaluation is the first comprehensive evaluation of the Weatherization Assistance Program since 1984. The evaluation was designed to accomplish the following goals: Estimate energy savings and cost effectiveness; Assess nonenergy impacts; Describe the weatherization network; Characterize the eligible population and resources; and Identify factors influencing outcomes and opportunities for the future. As a national program, weatherization incorporates considerable diversity due to regional differences. Therefore, evaluation results are presented both in aggregate and for three climate regions: cold, moderate and hot.

Brown, M.A.; Berry, L.G. [Oak Ridge National Lab., TN (United States); Kinney, L.F. [Synertech Systems Corp., Syracuse, NY (United States)

1993-11-01

405

Weathering of Mars - Antarctic analog studies  

NASA Technical Reports Server (NTRS)

Subaerial extrusion of lavas above permafrost is proposed as a possible weathering regime leading to the presence of Martian surface fines, and the characteristics of this process are examined through a study of the analogous altered terrestrial basalts from Antarctica. On the basis of mineralogical and petrological analyses of samples obtained from core cuttings recovered by the Dry Valley Drilling Program from rocks predominantly of an aklalic basalt-phonolite suite, it is found that in the absence of liquid water, weathering is geologically slow, and that zeolites predominate over clays as secondary mineral. Of the possible weathering processes proposed for Mars, it is concluded that both subaerial extrusion and subpermafrost intrusion of lavas involving liquid water would be less important volumetrically than the hydrothermal alteration of impact melt sheets if water were present during an intense phase of early bombardment, or than subsequent solid-gas alteration reactions. It is thus predicted that the present Martian fines should contain a major contribution from the ancient crust as typified by the southern cratered highlands, and a lesser contribution from the younger basaltic lavas.

Berkley, J. L.; Drake, M. J.

1981-01-01

406

Rock preconditioning to prevent rock bursts  

SciTech Connect

A US Bureau of Mines method to precondition rocks to prevent rock bursts is presented. The approach uses deep drill holes from a mine opening in a radial pattern in the vein and load and blast to fracture the rock prior to production mining. The method was successfully tested on a sphalerite-galena vein in a hard gangue of quartz and quartzite at the 7700 level of the Hecla Mining Company's Star Mine in Burke, Idaho. (JMT)

Not Available

1981-05-01

407

Towards Weather Ethics: From Chance to Choice with Weather Modification  

Microsoft Academic Search

The field of weather and climate ethics is a novel branch of applied ethics, based on environmental sciences and philosophy. Due to recent scientific findings concerning climate change, intentional weather and climate modification schemes have become even more relevant to finding feasible ways to moderate climate change and therefore are in need of careful analysis. When, if ever, can weather

Sanna Joronen; Markku Oksanen; Timo Vuorisalo

2011-01-01

408

External Resource: Erosion and Weathering  

NSDL National Science Digital Library

This is a Teachers' Domain photo essay with images that depict surface features on Earth that result from weathering and erosion, as well as measures designed to mitigate their unwanted effects. Topics: weathering, erosion, sediments, dunes, deltas, glaci

1900-01-01

409

Food Safety for Warmer Weather  

MedlinePLUS

... our exit disclaimer . Subscribe Fight Off Food Poisoning Food Safety for Warmer Weather In warm-weather months, who ... they produce,” says Dr. Alison O’Brien, a food safety expert at the Uniformed Services University of the ...

410

Cold Weather and Cardiovascular Disease  

MedlinePLUS

Cold Weather and Cardiovascular Disease Updated:Oct 28,2014 Th is winter season will bring cooler temperatures and ice ... for some. It’s important to know how cold weather can affect your heart, especially if you have ...

411

Rock Cycle Learning Module  

NSDL National Science Digital Library

This rock cycle unit was designed to be used with a college course in physical geography. From this module, students learn to distinguish between minerals and rocks, how rocks are classified, and how rocks are constantly recycled providing raw materials for other rocks. Igneous rocks are discussed on the basis of being intrusive or extrusive, sedimentary rocks are divided into clastic and non-clastic, while the metamorphic rocks are described as being foliated or non-foliated and common examples are cited for each classification. The processes and conditions of rock formation are also discussed. The module contains a study guide and outline notes, study questions, and a practice quiz. One feature of the module is a web exploration section with links to fifteen outside sites that augment the instruction.

Haberlin, Rita

412

Pitted rock surfaces on Mars: A mechanism of formation by transient melting of snow and ice  

E-print Network

stable upland zone of the Antarctic Dry Valleys; these form by very localized chemical weathering due in the stable upland zone of the Antarctic Dry Valleys, pit formation by transient melting of small amounts, and combinations of these. [3] On Earth, weathering pits are common features on rocks in the Antarctic Dry Valleys

Marchant, David R.

413

Interactives: The Rock Cycle  

NSDL National Science Digital Library

How much do you know about rocks? Well, if you are a bit unsure about distinguishing an igneous rock from a sedimentary rock you'll certainly be on solid ground after taking a tour through this feature created by Annenberg Media. Visitors can make their way through graphically-enhanced sections that include "Types of Rocks", "How Rocks Change", and "The Rock Cycle Diagram". In the "Types of Rocks" area visitors will learn about the basic types of rocks and they can even check out a handy chart that will give them some of the finer points of rock identification. The "How Rocks Change" area provides a basic overview of the processes involved with rock creation and transformation through a heady blend of Flash animations and straight-forward prose. Finally, the "Rock Cycle Diagram" provides an illustration of rock transformation over time. This site will be quite useful to educators and anyone who has peered at a rock and wondered: "How did you come to be?"

2008-04-11

414

Interactives: The Rock Cycle  

NSDL National Science Digital Library

How much do you know about rocks? Well, if you are a bit unsure about distinguishing an igneous rock from a sedimentary rock you'll certainly be on solid ground after taking a tour through this feature created by Annenberg Media. Visitors can make their way through graphically-enhanced sections that include "Types of Rocks", "How Rocks Change", and "The Rock Cycle Diagram". In the "Types of Rocks" area visitors will learn about the basic types of rocks and they can even check out a handy chart that will give them some of the finer points of rock identification. The "How Rocks Change" area provides a basic overview of the processes involved with rock creation and transformation through a heady blend of Flash animations and straight-forward prose. Finally, the "Rock Cycle Diagram" provides an illustration of rock transformation over time. This site will be quite useful to educators and anyone who has peered at a rock and wondered: "How did you come to be?"

415

Space Weather Impacts on Aviation  

NSDL National Science Digital Library

Space Weather Impacts on Aviation examines the effects of solar flares, coronal mass ejections, and other solar phenomena on aviation operations. The module builds on background science knowledge taught in the course prerequisite, Space Weather Basics, 2nd Edition. The content gives aviation forecasters and others an overview of the information and products available from NOAA's Space Weather Prediction Center and provides practice interpreting and using those products for decision support during space weather events.

Comet

2012-06-12

416

Spring Break-Weathering Homework  

NSDL National Science Digital Library

Students are asked to photograph something that shows either physical or chemical weathering. They must be in the photograph for purposes of scale. They must then write up their description of the weathering feature and explain the actual weathering processes. This assignment can also be expanded to include mass wasting and mass wasting prevention.

Farthing, Dori

417

Differences Between Climate and Weather  

NSDL National Science Digital Library

In this activity, students collect weather data over several days or weeks, graph temperature data, and compare the temperature data collected with long-term climate averages from where they live. Understanding the difference between weather and climate and interpreting local weather data are important first steps to understanding larger-scale global climate changes.

Research, National C.

418

Weather Modification: Finding Common Ground  

Microsoft Academic Search

Research and operational approaches to weather modification expressed in the National Research Council's 2003 report on ``Critical Issues in Weather Modification Research'' and in the Weather Modification Association's response to that report form the basis for this discussion. There is agreement that advances in the past few decades over a broad front of understanding physical processes and in technology have

Michael Garstang; Roelof Bruintjes; Robert Serafin; Harold Orville; Bruce Boe; William Cotton; Joseph Warburton

2005-01-01

419

Science Sampler: Clever with weather  

NSDL National Science Digital Library

In eighth-grade Earth science at Louisville Middle School in Louisville, Colorado, students learn how large-scale weather patterns such as the jet stream and weather fronts interact to generate local weather conditions. The authors have developed a modeli

Crowder, David; Hoenigman, Rhonda

2011-02-01

420

Weather Forecasting for Radio Astronomy  

E-print Network

Weather Forecasting for Radio Astronomy Part I: The Mechanics and Physics Ronald J Maddalena August 1, 2008 #12;Outline Part I Background -- research inspirations and aspirations Vertical weather, .... Part II Results on refraction & air mass (with Jeff Paradis) Part III Results on opacity, weather

Groppi, Christopher

421

Severe Weather Planning for Schools  

ERIC Educational Resources Information Center

Flash floods, severe thunderstorms, and tornadoes occur with rapid onset and often no warning. Decisions must be made quickly and actions taken immediately. This paper provides tips for schools on: (1) Preparing for Severe Weather Emergencies; (2) Activating a Severe Weather Plan; (3) Severe Weather Plan Checklist; and (4) Periodic Drills and…

Watson, Barbara McNaught; Strong, Christopher; Bunting, Bill

2008-01-01

422

Online Field Journal: Rocks  

NSDL National Science Digital Library

This site allows students to take a closer look at three rocks: Gowganda Tillite, Loraine Quartzite, and Gowganda Glacial Conglomerate. On the opening page, there are side-by-side photos of the three rocks and students are asked to describe each one. Clicking a photo of the rock takes students to a magnified view of the rock. The site also includes links to a Tips for Adult Helpers page and to a printable Rocks Field Journal page that has instructions for using it on a rock hunt.

423

WEATHERING OF IRONBEARING MINERALS IN SOILS AND SAPROLITE ON THE NORTH CAROLINA BLUE RIDGE FRONT: II. CLAY MINERALOGY  

Microsoft Academic Search

The mineralogy of the clay fraction was studied for soils and saprolite on two Blue Ridge Front mountain slopes. The clay fraction contained the weathering products of primary minerals in the mica gneiss and schist parent rocks. Gibbsite is most abundant in the saprolite and residual soil horizons, where only chemical weathering has been operable. In colluvial soil horizons, where

D. D. AMARASIRIWARDENA; S. W. BUOL

424

Sulfuric acid as an agent of carbonate weathering constrained by ? 13C DIC: Examples from Southwest China  

Microsoft Academic Search

Rock weathering by carbonic acid is thought to play an important role in the global carbon cycle because it can geologically sequestrate atmospheric CO2. Current model of carbon cycle evolution usually assumes that carbonic acid is the major weathering agent and that other acids are not important. Here, we use carbon isotopic evidence and water chemistry of springs and rivers

Si-Liang Li; Damien Calmels; Guilin Han; Jérôme Gaillardet; Cong-Qiang Liu

2008-01-01

425

Chemical weathering, river geochemistry and atmospheric carbon fluxes from volcanic and ultramafic regions on Luzon Island, the Philippines  

Microsoft Academic Search

We investigated rates of chemical weathering of volcanic and ophiolitic rocks on Luzon Island, the Philippines. Luzon has a tropical climate and is volcanically and tectonically very active, all factors that should enhance chemical weathering. Seventy-five rivers and streams (10 draining ophiolites, 65 draining volcanic bedrock) and two volcanic hot springs were sampled and analyzed for major elements, alkalinity and

H. H. Schopka; L. A. Derry; C. A. Arcilla

2011-01-01

426

Whether weather affects music  

NASA Astrophysics Data System (ADS)

The creative output of composers, writers, and artists is often influenced by their surroundings. To give a literary example, it has been claimed recently that some of the characters in Oliver Twist and A Christmas Carol were based on real-life people who lived near Charles Dickens in London [Richardson, 2012]. Of course, an important part of what we see and hear is not only the people with whom we interact but also our geophysical surroundings. Of all the geophysical phenomena to influence us, the weather is arguably the most significant because we are exposed to it directly and daily. The weather was a great source of inspiration for artists Claude Monet, John Constable, and William Turner, who are known for their scientifically accurate paintings of the skies [e.g., Baker and Thornes, 2006].

Aplin, Karen L.; Williams, Paul D.

2012-09-01

427

National Weather Service Glossary  

NSDL National Science Digital Library

This glossary contains information on more than 2000 terms, phrases and abbreviations used by the National Weather Service (NWS). Many of these terms and abbreviations are used by NWS forecasters to communicate between each other and have been in use for many years; the glossary will aid users in better understanding NWS products. The glossary is searchable by keyword or browsable by letter of the alphabet.

428

National Weather Service Glossary  

NSDL National Science Digital Library

This glossary contains information on more than 2000 terms, phrases and abbreviations used by the National Weather Service (NWS). Many of these terms and abbreviations are used by NWS forecasters to communicate between each other and have been in use for many years; the glossary will aid users in better understanding NWS products. The glossary is searchable by keyword or browsable by letter of the alphabet.

2010-09-03

429

Long-term rates of chemical weathering and physical erosion from cosmogenic nuclides and geochemical mass balance  

Microsoft Academic Search

Quantifying long-term rates of chemical weathering and physical erosion is important for understanding the long-term evolution of soils, landscapes, and Earth's climate. Here we describe how long-term chemical weathering rates can be measured for actively eroding landscapes using cosmogenic nuclides together with a geochemical mass balance of weathered soil and parent rock. We tested this approach in the Rio Icacos

Clifford S. Riebe; James W. Kirchner; Robert C. Finkel

2003-01-01

430

Pipelines and Space Weather  

NASA Astrophysics Data System (ADS)

Long conductors of all types on Earth's surface are subject to disturbance and disruption by telluric currents (currents that flow within the Earth or on its surface) induced by space weather events. Attention is most often paid to the effects that these currents can produce in electric grids. After all, if an electric power system is disrupted, many other modern infrastructures that depend on the secure and continuous supply of electrical power will also be affected. A recent technical paper in Space Weather by R. A. Marshall and colleagues draws needed attention to the effects of telluric currents on long pipelines. This is a space weather topic that often does not receive the attention it warrants in terms of its critical relevance to modern-day life. Pipelines have long used cathodic protection systems to mitigate the corrosion of the pipes that can arise from potential differences between the ground and the pipes. These potential differences occur because telluric currents flow more readily in the pipes than in the ground. While pipeline engineers have long worked hard on this problem, it was the design and installation in the mid-1970s of the Alaska pipeline directly under the auroral zone that drew enhanced attention to this topic.

Lanzerotti, Louis J.

2010-05-01

431

Modelling the evolution of natural cliffs subject to weathering: II. Discrete elements approach  

NASA Astrophysics Data System (ADS)

The evolution of slopes subjected to weathering has been modelled by assuming Mohr-Coulomb behaviour, and by using a numerical approach based on the Distinct Element Method. According to this method, soil/rock is represented by an assembly of bonded particles. Particle bonds are subject to progressive weakening and so the material weathering and removal processes are modelled. Slope instability and material movement follow the decrease of material strength in space and time with the only assumption concerning the weathering distribution within the slope. Firstly, the case of cliffs subject to strong erosion (weathering-limited conditions) and uniform weathering was studied to validate the DEM approach by comparison against analytical predictions from limit analysis (see companion abstract). Secondly, transport-limited slopes subject to non-uniform slope weathering were studied. Results have been compared with experimental data and other geomorphologic models from the literature [Fisher-Lehmann, Bakker-Le Heux].

Utili, S.; Crosta, G. B.

2009-04-01

432

Rock Mech. Rock Engng. (2000) 33 (1), 113 Rock Mechanics  

E-print Network

Hammer test is very similar in principle to a down-hole hammer while drill- ing, a patent in 1971 was in a good agreement with rock drillability or cutting ability, to the knowledge of the authors there does

433

Rock fragment distributions and regolith evolution in the Ouachita Mountains, Arkansas, USA  

Microsoft Academic Search

Rock fragments in the regolith are a persistent property that reflects the combined influences of geologic controls, erosion, deposition, bioturbation, and weathering. The distribution of rock fragments in regoliths of the Ouachita Mountains, Arkansas, shows that sandstone fragments are common in all layers, even if sandstone is absent in parent material. Shale and sandstone fragments are produced at the bedrock

Jonathan D. Phillips; Ken Luckow; Daniel A. Marion; Kristin R. Adams

2005-01-01

434

Sedimentary rocks at Meridiani Planum: Origin, diagenesis, and implications for life on Mars  

Microsoft Academic Search

The MER rover Opportunity has carried out the first outcrop-scale investigation of ancient sedimentary rocks on Mars. The rocks, exposed in craters and along fissures in Meridiani Planum, are sandstones formed via the erosion and re-deposition of fine grained siliciclastics and evaporites derived from the chemical weathering of olivine basalts by acidic waters. A stratigraphic section more than seven meters

Steven W. Squyres; Andrew H. Knoll

2005-01-01

435

SOURCE AND EFFECT OF ACID ROCK DRAINAGE IN THE SNAKE RIVER WATERSHED, SUMMIT COUNTY, COLORADO  

E-print Network

SOURCE AND EFFECT OF ACID ROCK DRAINAGE IN THE SNAKE RIVER WATERSHED, SUMMIT COUNTY, COLORADO Drainage in the Snake River Watershed, Summit County, Colorado Thesis directed by Dr. Diane M. Mc (the weathering of disseminated pyrite) sources of acid rock drainage (ARD). Stream waters

436

Research Article Astrobiological Implications of Rock Varnish in Tibet  

E-print Network

from warm arid desert regions. Here, we examine samples obtained from eolian-abraded lava flows coating--Rock varnish--Microstromatolite--Tibet--Weathering. Astrobiology 9, 551­562. Introduction Ever since shiny dark coatings were first imaged by cameras on board the 1976 Viking landers (Moore et al

Dorn, Ron

437

The Rock Cycle  

ERIC Educational Resources Information Center

Presents a rock cycle diagram suitable for use at the secondary or introductory college levels which separates rocks formed on and below the surface, includes organic materials, and separates products from processes. (SL)

Singh, Raman J.; Bushee, Jonathan

1977-01-01

438

Igneous Rock Animation  

NSDL National Science Digital Library

Through a simple Flash roll over, view hand specimens of different igneous rocks classified according by texture and chemical composition. There are also views of the more common rock forming minerals. Expect long loading times.

Wiley

439

Igneous Rock Identification  

NSDL National Science Digital Library

This activity is designed to provide students with the opportunity to analyze the textures of various igneous rocks and use these textures as a basis for classification and identification. Students will develop visual identification skills for the common igneous rocks and learn that igneous rocks are those that cool from molten rock materials known as magma. They will discover that igneous rocks are classified on the basis of their texture and their mineralogical composition. Texture is the overall size, shape, and arrangement of the mineral grains that make up the rock. Students will also realize that rocks containing more silica, such as granite and rhyolite, are generally lighter in color while dark colored rocks commonly have the composition of gabbro or basalt.

440

Metamorphic Rock Pancakes  

NSDL National Science Digital Library

In this activity, students identify the properties of metamorphic rocks and learn that they are formed by heat and pressure. Using a griddle and pancake batter, they will make metamorphic "rocks" and eat them.

1998-01-01

441

The Rock Cycle  

NSDL National Science Digital Library

This site from Satellite Geodesy describes the rock cycle, and quantitative ways to estimate how long geological features took to form. Popcorn is used to demonstrate half-life and radio-active decay, which is used to date rocks.

Tauxe, Lisa; Geodesy, Satellite

442

Rock Cycle Animations  

NSDL National Science Digital Library

Many people might know about the life cycle of a rock, but it can be a process that is hard to understand without a handy visual aid. Just such a series of aids can be found right here, courtesy of Mark Francek of Central Michigan University. These rock cycle animations display some of the most common rock-forming processes, including the crystallization of magma to form igneous rock, rock erosion to create sediment, and several others. That's not all, as visitors can also examine a comprehensive Flash animation which contains three separate movies, each of which looks at the formation of igneous rocks in environments that include a deep magma chamber and rocks forming from a pyroclastic flow. The site is rounded out by an interactive igneous rocks classification chart, arranged by texture and chemical composition.

443

Theory of wing rock  

NASA Technical Reports Server (NTRS)

Wing rock is one type of lateral-directional instabilities at high angles of attack. To predict wing rock characteristics and to design airplanes to avoid wing rock, parameters affecting wing rock characteristics must be known. A new nonlinear aerodynamic model is developed to investigate the main aerodynamic nonlinearities causing wing rock. In the present theory, the Beecham-Titchener asymptotic method is used to derive expressions for the limit-cycle amplitude and frequency of wing rock from nonlinear flight dynamics equations. The resulting expressions are capable of explaining the existence of wing rock for all types of aircraft. Wing rock is developed by negative or weakly positive roll damping, and sustained by nonlinear aerodynamic roll damping. Good agreement between theoretical and experimental results is obtained.

Hsu, C.-H.; Lan, C. E.

1985-01-01

444

Physical weathering of marbles caused by anisotropic thermal expansion  

Microsoft Academic Search

Marbles as building stones as well as in their natural environments show complex weathering phenomena. The most important\\u000a damage scenario is based on the highly anisotropic thermal expansion coefficient ? of calcite, i.e. extreme expansion parallel and contraction normal to the crystallographic c-axis. Therefore, the rock fabric\\u000a and especially the lattice-preferred orientation (texture) of calcite and\\/or dolomite as the predominant

S. Siegesmund; K. Ullemeyer; T. Weiss; E. K. Tschegg

2000-01-01

445

Characterization of Fungal Community Structure on a Weathered Pegmatitic Granite  

Microsoft Academic Search

This study exploited the contrasting major element chemistry of adjacent, physically separable crystals of framework and sheet\\u000a silicates in a pegmatitic granite to investigate the mineralogical influences of fungal community structure on mineral surfaces.\\u000a Large intact crystals of variably weathered muscovite, plagioclase, K-feldspar, and quartz were individually extracted, together\\u000a with whole-rock granite. Environmental scanning electron microscopy (ESEM) revealed a diversity

Deirdre B. Gleeson; Nicholas Clipson; Karrie Melville; Geoffrey M. Gadd; Frank P. McDermott

2005-01-01

446

68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: ...  

Library of Congress Historic Buildings Survey, Historic Engineering Record, Historic Landscapes Survey

68. LITTLE ROCK AND PALMDALE IRRIGATION DISTRICT, LITTLE ROCK DAM: STRESS SHEET, SHEET 4; MAY, 1918. Littlerock Water District files. - Little Rock Creek Dam, Little Rock Creek, Littlerock, Los Angeles County, CA

447

Igneous Rocks Animation  

NSDL National Science Digital Library

In this section, see close-up pictures of the major rock types and learn about where different types of igneous rocks are formed, what style of magmatic activity is associated with each type of magma, and what rock types are melted to form each of these magma compositions.

2002-01-01

448

Friction of rocks  

Microsoft Academic Search

Experimental results in the published literature show that at low normal stress the shear stress required to slide one rock over another varies widely between experiments. This is because at low stress rock friction is strongly dependent on surface roughness. At high normal stress that effect is diminished and the friction is nearly independent of rock type. If the sliding

J. Byerlee

1978-01-01

449

Everybody Needs a Rock  

NSDL National Science Digital Library

This lesson introduces students to properties of rocks, specifically weight and density. They will select a rock, make a list of words to describe it, estimate its mass and use a balance to check their estimates, write a story about what they have learned, and group or classify the rocks according to what they have learned.

450

Soil vs. Rocks  

NSDL National Science Digital Library

This lesson will extend the learning on rocks with the Foss kit, Pebbles, Sand, and Silt to include soil. Students will perform the soil sifting activity like the one designed for rocks in the Foss it. Through their work, students will complete a Venn diagram of soil and rocks as a class.

Ama Xiong, Ames Elementary School, Saint Paul, MN Based on an original activity from the FOSS Kit, Pebbles, Sand, & Silt.

451

The Rock Physics Handbook  

Microsoft Academic Search

The Rock Physics Handbook conveniently brings together the theoretical and empirical relations that form the foundations of rock physics, with particular emphasis on seismic properties. It also includes commonly used models and relations for electrical and dielectric rock properties. Seventy-six articles concisely summarize a wide range of topics, including wave propagation, AVO-AVOZ, effective media, poroelasticity, pore fluid flow and diffusion.

Gary Mavko; Tapan Mukerji; Jack Dvorkin

2003-01-01

452

Rock and Sexuality.  

ERIC Educational Resources Information Center

Discusses rock as a form of both sexual expression and control. Describes rock's representations of masculinity and femininity and considers the contradictions involved in the representations. Relates the effects of rock to its form--as music, as commodity, as culture, and as entertainment. (JMF)

Frith, Simon; McRobbie, Angela

1978-01-01

453

Metamorphic Rocks Lab  

NSDL National Science Digital Library

Students each obtain 2 rock samples from a collection of 20 for the lab. Students complete a data form for observations concerning metamorphic features. Each student identifies the 2 samples and describes the metamorphic parent rock. When everyone in the lab has finished, the group matches all the non-metamorphic samples to the metamorphic samples in a large rock cycle puzzle.

Hadley, Ann C.

454

Pollution implications of Save River water from weathering and dissolution of metal hosting minerals at Dorowa phosphate mine, Zimbabwe  

Microsoft Academic Search

The study set out to determine the weathering and dissolution of metal hosting minerals at Dorowa for purposes of deducing pollution potential to the nearby Save River. Phosphate rock is mined at Dorowa for the production of phosphate fertilizer. The major minerals found in the ring complex are feldspars, pyroxenes, apatite, magnetite and calcite. Chemical analysis established that the rocks

M. L. Meck; J. Atlhopheng; W. R. L. Masamba; S. Ringrose

2010-01-01

455

Fossil Microorganisms and Formation of Early Precambrian Weathering Profiles  

NASA Technical Reports Server (NTRS)

Weathering crusts are the only reliable evidences of the existence of continental conditions. Often they are the only source of information about exogenous processes and subsequently about conditions under which the development of the biosphere occurred. A complex of diverse fossil microorganisms was discovered as a result of Scanning Electron Microscope investigations. The chemical composition of the discovered fossils is identical to that of the host rocks and is represented by Si, Al, Fe, Ca and Mg. Probably, the microorganisms fixed in rocks played the role of catalyst. The decomposition of minerals comprising the rocks and their transformation into clayey (argillaceous) minerals, most likely occurred under the influence of microorganisms. And may be unique weathering crusts of Early Precambrian were formed due to interaction between specific composition of microorganism assemblage and conditions of hypergene transformations. So it is possible to speak about colonization of land by microbes already at that time and about existence of single raw from weathering crusts (Primitive soils) to real soils.

Rozanov, A. Yu; Astafieva, M. M.; Vrevsky, A. B.; Alfimova, N. A.; Matrenichev, V. A.; Hoover, R. B.

2009-01-01

456

Green Bank Weather Dana S. Balser  

E-print Network

Green Bank Weather Dana S. Balser #12;Weather Resources 1. Weather Stations 2. Weather Forecasts (NOAA/Maddalena) 3. Pyrgeometer 4. 86 GHz Tipping Radiometer 5. 12 GHz Interferometer #12;Weather Parameters 1 May 2004 to 1 March 2007 speedwindousInstantaneV :Hz)(12StationWeather e

Balser, Dana S.

457

Nitrogen in rock: Occurrences and biogeochemical implications  

NASA Astrophysics Data System (ADS)

There is a growing interest in the role of bedrock in global nitrogen cycling and potential for increased ecosystem sensitivity to human impacts in terrains with elevated background nitrogen concentrations. Nitrogen-bearing rocks are globally distributed and comprise a potentially large pool of nitrogen in nutrient cycling that is frequently neglected because of a lack of routine analytical methods for quantification. Nitrogen in rock originates as organically bound nitrogen associated with sediment, or in thermal waters representing a mixture of sedimentary, mantle, and meteoric sources of nitrogen. Rock nitrogen concentrations range from trace levels (<200 mg N kg-1) in granites to ecologically significant concentrations exceeding 1000 mg N kg-1 in some sedimentary and metasedimentary rocks. Nitrate deposits accumulated in arid and semi-arid regions are also a large potential pool. Nitrogen in rock has a potentially significant impact on localized nitrogen cycles. Elevated nitrogen concentrations in water and soil have been attributed to weathering of bedrock nitrogen. In some environments, nitrogen released from bedrock may contribute to nitrogen saturation of terrestrial ecosystems (more nitrogen available than required by biota). Nitrogen saturation results in leaching of nitrate to surface and groundwaters, and, where soils are formed from ammonium-rich bedrock, the oxidation of ammonium to nitrate may result in soil acidification, inhibiting revegetation in certain ecosystems. Collectively, studies presented in this article reveal that geologic nitrogen may be a large and reactive pool with potential for amplification of human impacts on nitrogen cycling in terrestrial and aquatic ecosystems.

Holloway, Joann M.; Dahlgren, Randy A.

2002-12-01

458

Nitrogen in rock: Occurrences and biogeochemical implications  

USGS Publications Warehouse

There is a growing interest in the role of bedrock in global nitrogen cycling and potential for increased ecosystem sensitivity to human impacts in terrains with elevated background nitrogen concentrations. Nitrogen-bearing rocks are globally distributed and comprise a potentially large pool of nitrogen in nutrient cycling that is frequently neglected because of a lack of routine analytical methods for quantification. Nitrogen in rock originates as organically bound nitrogen associated with sediment, or in thermal waters representing a mixture of sedimentary, mantle, and meteoric sources of nitrogen. Rock nitrogen concentrations range from trace levels (>200 mg N kg -1) in granites to ecologically significant concentrations exceeding 1000 mg N kg -1 in some sedimentary and metasedimentary rocks. Nitrate deposits accumulated in arid and semi-arid regions are also a large potential pool. Nitrogen in rock has a potentially significant impact on localized nitrogen cycles. Elevated nitrogen concentrations in water and soil have been attributed to weathering of bedrock nitrogen. In some environments, nitrogen released from bedrock may contribute to nitrogen saturation of terrestrial ecosystems (more nitrogen available than required by biota). Nitrogen saturation results in leaching of nitrate to surface and groundwaters, and, where soils are formed from ammonium-rich bedrock, the oxidation of ammonium to nitrate may result in soil acidification, inhibiting revegetation in certain ecosystems. Collectively, studies presented in this article reveal that geologic nitrogen may be a large and reactive pool with potential for amplification of human impacts on nitrogen cycling in terrestrial and aquatic ecosystems.

Holloway, J.M.; Dahlgren, R.A.

2002-01-01

459

Endophytic bacteria of Mammillaria fraileana , an endemic rock-colonizing cactus of the southern Sonoran Desert  

Microsoft Academic Search

The small cactus Mammillaria fraileana is a pioneer rock-colonizing plant harboring endophytic bacteria with the potential for nitrogen fixation and rock weathering\\u000a (phosphate solubilization and rock degradation). In seeds, only a combination of culture-independent methods, such as fluorescence\\u000a in situ hybridization, scanning electron microscopy, and fluorescence vital staining, detected significant amounts of non-culturable,\\u000a but living, endophytic bacteria distributed underneath the

Blanca R. Lopez; Yoav Bashan; Macario Bacilio

2011-01-01

460

Deriving chemical trends from thermal infrared spectra of weathered basalt: Implications for remotely determining chemical trends on Mars  

NASA Astrophysics Data System (ADS)

Variations in chemical composition over a planetary surface can be used to study petrologic and aqueous alteration processes. The desire for such data on Mars has prompted investigators to derive chemistry from models of Thermal Emission Spectrometer data. Although chemistry derived from thermal infrared spectral models is reportedly reliable for unaltered igneous rocks, the martian surface has experienced chemical weathering, which can adversely affect models. Here, we examine weathered basalts from Baynton, Australia, for which chemical weathering trends have been previously characterized, to test how well chemistry and chemical trends can be determined from TIR spectra of weathered rocks. The mineralogy of variably weathered rocks was derived from TIR spectra by linear mixing, and major-element chemistry was calculated from those mineral models. Derived chemistries and trends were compared to those measured by X-ray fluorescence. TIR spectroscopy is sensitive to weathering products in weathering rinds because the products are present in a coating geometry, making it a useful technique for remotely detecting weathered surfaces on planetary surfaces such as Mars. This sensitivity results in significant modeled abundances of weathering products (>80% of all phases) from TIR spectra of weathered Baynton surfaces, despite evidence from microscopy and X-ray diffraction showing that igneous minerals dominate the weathering rind. Measured chemical weathering trends show loss of MgO, CaO, Na2O, and K2O and relative enrichment in Al2O3 and FeOT. The modeled trends are similar to the measured trends, but a closer look at the modeled oxide abundances demonstrates that most oxides (i.e., alkalis, SiO2, and FeOT) are not well modeled, especially for weathered surfaces. The reasons for this are: (1) non-linear mixing and the presence of secondary coatings causes the overestimation of secondary phases in spectral models, and (2) spectral libraries generally lack poorly crystalline and amorphous secondary phases that are common in weathering rinds so that crystalline phases such as phyllosilicates are selected. The martian surface has likely been weathered less pervasively than the Baynton rocks and, therefore, weathering products may be dominated by poorly crystalline and amorphous phases, rather than crystalline phyllosilicates. Adding these phases to spectral libraries could improve bulk chemistry derived from the martian surface; however, if the secondary phases are present in a coating geometry, the derived chemistry will reflect the composition of the coating, and it may be difficult to infer the chemistry of the parent rock.

Rampe, Elizabeth B.; Kraft, Michael D.; Sharp, Thomas G.

2013-07-01

461

Severe Weather Forecast Decision Aid  

NASA Technical Reports Server (NTRS)

This report presents a 15-year climatological study of severe weather events and related severe weather atmospheric parameters. Data sources included local forecast rules, archived sounding data, Cloud-to-Ground Lightning Surveillance System (CGLSS) data, surface and upper air maps, and two severe weather event databases covering east-central Florida. The local forecast rules were used to set threat assessment thresholds for stability parameters that were derived from the sounding data. The severe weather events databases were used to identify days with reported severe weather and the CGLSS data was used to differentiate between lightning and non-lightning days. These data sets provided the foundation for analyzing the stability parameters and synoptic patterns that were used to develop an objective tool to aid in forecasting severe weather events. The period of record for the analysis was May - September, 1989 - 2003. The results indicate that there are certain synoptic patterns more prevalent on days with severe weather and some of the stability parameters are better predictors of severe weather days based on locally tuned threat values. The results also revealed the stability parameters that did not display any skill related to severe weather days. An interactive web-based Severe Weather Decision Aid was developed to assist the duty forecaster by providing a level of objective guidance based on the analysis of the stability parameters, CGLSS data, and synoptic-scale dynamics. The tool will be tested and evaluated during the 2005 warm season.

Bauman, William H., III; Wheeler, Mark M.; Short, David A.

2005-01-01

462

Igneous Rock Crystallization Animation  

NSDL National Science Digital Library

This Flash animation contains three separate movies, each exhibiting the formation of an igneous rocks in a different environment: a) rocks forming from a deep magma chamber where the slow cooling of magma results in large interlocking crystals; b) rocks forming from a pyroclastic flow with a combination of large and small crystals; and c) rocks with small crystals created from a fast cooling lava. The rock is further modified by bubbles from dissolved gases resulting in vesicles. Each movie concludes with a view of a hand specimen representative of each environment. The animation can be paused and rewound to stress important points.

Armstrong, Lenni; Earth, Exploring

463

Finding Space Weather Events  

NSDL National Science Digital Library

This is an activity about searching online data archives for solar wind events. Learners will find at least three episodes of increased solar wind activity impacting Earth using direct measurements of solar wind velocity and density. Then, they will characterize each events by its rise time, the time it takes for the solar wind speed to rise from normal levels to the peak speed of the event, and the percentage increase in solar wind velocity. This is Activity 11 of the Space Weather Forecast curriculum.

464

Weather Stations: Phase Change  

NSDL National Science Digital Library

In this activity, learners observe the water cycle in action! Water vapor in a tumbler condenses on chilled aluminum foil â producing the liquid form of water familiar to us as rain and dew. Learners discuss how Jupiter's lack of a surface simplifies its water cycle. Learners then consider the roles ammonia and ammonia compounds play in Jupiter's more complicated atmosphere. This activity is one station that can be combined with other stations for an hour and half lesson on weather patterns on Jupiter and Earth.

Institute, Lunar A.; Nasa

2011-01-01

465

Chemical weathering response to tectonic forcing: A soils perspective from the San Gabriel Mountains, California  

NASA Astrophysics Data System (ADS)

What controls the chemical weathering of soils in tectonically active landscapes? Recent field and modeling studies suggest that tectonic forcing and associated increases in erosion rates may either promote or hinder soil chemical weathering. These competing trajectories are dependent on two primary controls: the availability of fresh minerals and their residence time on the landsurface. Here, we explore rates and extents of soil weathering in the San Gabriel Mountains of California, where previous work has measured clear tectonic fingerprints on rates of long term exhumation, hillslope erosion and landscape morphology. We quantify chemical weathering across this landscape by elemental analysis of soils, saprolites and bedrock on six sites that bracket the low-gradient hillslopes of the relict upland plateau and the high-gradient hillslopes at the margins of the tectonically-driven incising landscape. Average chemical depletion fractions, which measure weathering losses from soil relative to unweathered parent material, decrease with increasing elevation and decreasing temperature, reflecting a combination of climate influence and potential dust inputs from the Mojave Desert. Weathering fluxes from non-dust-affected sites with similar elevations, climates and lithology correlate with both erosion rates and hillslope gradient. On low-gradient hillslopes (< 25°), weathering rates increase with increasing erosion rates, reflecting the influence of mineral supply. However, on high-gradient hillslopes (> 25°), weathering intensities and rates both decrease as erosion rates increase and soils thin. At the highest denudation rates (> 300 t km- 2 y- 1), saprolite production is outpaced, and soils are produced directly from fractured rock. These patterns are consistent with those predicted by a previously published model for denudation-weathering relationships based on mineral weathering kinetics. Variable weathering extents in soils indicate that weathering in the SGM is largely kinetically limited. This study is the first to quantify decreases in both rates and extents of soil chemical weathering with increasing erosion rates, and suggests tectonic uplift in rapidly eroding and incising landscapes may not stimulate increased silicate weathering.

Dixon, Jean L.; Hartshorn, Anthony S.; Heimsath, Arjun M.; DiBiase, Roman A.; Whipple, Kelin X.

2012-03-01

466

NASA Space Weather Center Services: Potential for Space Weather Research  

NASA Technical Reports Server (NTRS)

The NASA Space Weather Center's primary objective is to provide the latest space weather information and forecasting for NASA's robotic missions and its partners and to bring space weather knowledge to the public. At the same time, the tools and services it possesses can be invaluable for research purposes. Here we show how our archive and real-time modeling of space weather events can aid research in a variety of ways, with different classification criteria. We will list and discuss major CME events, major geomagnetic storms, and major SEP events that occurred during the years 2010 - 2012. Highlights of major tools/resources will be provided.

Zheng, Yihua; Kuznetsova, Masha; Pulkkinen, Antti; Taktakishvili, A.; Mays, M. L.; Chulaki, A.; Lee, H.; Hesse, M.

2012-01-01

467

Weathering of the New Albany Shale, Kentucky, USA: I. Weathering zones defined by mineralogy and major-element composition  

USGS Publications Warehouse

Comprehensive understanding of chemical and mineralogical changes induced by weathering is valuable information when considering the supply of nutrients and toxic elements from rocks. Here minerals that release and fix major elements during progressive weathering of a bed of Devonian New Albany Shale in eastern Kentucky are documented. Samples were collected from unweathered core (parent shale) and across an outcrop excavated into a hillside 40 year prior to sampling. Quantitative X-ray diffraction mineralogical data record progressive shale alteration across the outcrop. Mineral compositional changes reflect subtle alteration processes such as incongruent dissolution and cation exchange. Altered primary minerals include K-feldspars, plagioclase, calcite, pyrite, and chlorite. Secondary minerals include jarosite, gypsum, goethite, amorphous Fe(III) oxides and Fe(II)-Al sulfate salt (efflorescence). The mineralogy in weathered shale defines four weathered intervals on the outcrop-Zones A-C and soil. Alteration of the weakly weathered shale (Zone A) is attributed to the 40-a exposure of the shale. In this zone, pyrite oxidization produces acid that dissolves calcite and attacks chlorite, forming gypsum, jarosite, and minor efflorescent salt. The pre-excavation, active weathering front (Zone B) is where complete pyrite oxidation and alteration of feldspar and organic matter result in increased permeability. Acidic weathering solutions seep through the permeable shale and evaporate on the surface forming abundant efflorescent salt, jarosite and minor goethite. Intensely weathered shale (Zone C) is depleted in feldspars, chlorite, gypsum, jarosite and efflorescent salts, but has retained much of its primary quartz, illite and illite-smectite. Goethite and amorphous FE(III) oxides increase due to hydrolysis of jarosite. Enhanced permeability in this zone is due to a 14% loss of the original mass in parent shale. Denudation rates suggest that characteristics of Zone C were acquired over 1 Ma. Compositional differences between soil and Zone C are largely attributed to illuvial processes, formation of additional Fe(III) oxides and incorporation of modern organic matter.

Tuttle, M.L.W.; Breit, G.N.

2009-01-01

468

Martian weathering products as tracers of climate change and atmosphere/hydrosphere evolution on Mars  

NASA Technical Reports Server (NTRS)

Primary objectives for exploration of Mars include determination of: (1) the distribution, abundance, and sources and sinks of volatile materials, and (2) the interaction of surface materials with the atmosphere. Both objectives fall within the purview of planetary surface weathering studies and require documented samples of weathered materials, including rock surfaces, soils, and sediments. Major issues to be addressed in selecting and studying Martian samples in this context are summarized.

Gooding, J. L.

1988-01-01

469

An aem-tem study of weathering and diagenesis, Abert Lake, Oregon: I. Weathering reactions in the volcanics  

USGS Publications Warehouse

Abert Lake in south-central Oregon provides a site suitable for the study of sequential weathering and diagenetic events. In this first of two papers, transmission electron microscopy was used to characterize the igneous mineralogy, subsolidus alteration assemblage, and the structural and chemical aspects of silicate weathering reactions that occur in the volcanic rocks (basalts, basaltic andesites, and dacitic/ rhyolitic extrusive and pyroclastics) that outcrop around the lake. Olivine and pyroxene replacement occurred topotactically, whereas feldspar and glass alteration produced randomly oriented smectite in channels and cavities. The tetrahedral, octahedral, and interlayer compositions of the weathering products, largely dioctahedral smectites, varied with primary mineral composition, rock type, and as the result of addition of elements released from adjacent reaction sites. Weathering of the highly evolved, Fe-rich Jug Mountain complex at the north end of the lake produced a homogeneous smectite assemblage that contrasts with the heterogeneous smectite assemblage replacing the volcanics along the eastern margin of the lake. The variability within and between the smectite assemblages highlights the microenvironmental diversity, fluctuating redox conditions, and variable solution chemistry associated with mineral weathering reactions in the surficial environment. Late-stage exhalative and aqueous alteration of the volcanics redistributed many components and formed a variety of alkali and alkali-earth carbonate, chloride, sulfate, and fluoride minerals in vugs and cracks. Overall, substantial Mg, Si, Na, Ca, and K are released by weathering reactions that include the almost complete destruction of the Mg-smectite that initially replaced olivine. The leaching of these elements from the volcanics provides an important source of these constituents in the lake water. The nature of subsequent diagenetic reactions resulting from the interaction between the materials transported to the lake and the solution will be described in part II (Banfield et al., 1991). ?? 1991.

Banfield, J. F.; Jones, B. F.; Veblen, D. R.

1991-01-01

470

Fluxes of high- versus low-temperature water rock interactions in aerial volcanic areas: Example from the Kamchatka Peninsula, Russia  

NASA Astrophysics Data System (ADS)

Volcanic areas play a key role in the input of elements into the ocean and in the regulation of the geological carbon cycle. The aim of this study is to investigate the budget of silicate weathering in an active volcanic area. We compared the fluxes of the two major weathering regimes occurring at low temperature in soils and at high temperature in the active volcanic arc of Kamchatka, respectively. The volcanic activity, by inducing geothermal circulation and releasing gases to the surface, produces extreme conditions in which intense water-rock interactions occur and may have a strong impact on the weathering budgets. Our results show that the chemical composition of the Kamchatka river water is controlled by surface low-temperature weathering, atmospheric input and, in some limited cases, strongly imprinted by high-temperature water-rock reactions. We have determined the contribution of each source and calculated the rates of CO 2 consumption and chemical weathering resulting from low and high-temperature water/rock interactions. The weathering rates (between 7 and 13.7 t/km 2/yr for cations only) and atmospheric CO 2 consumption rates (˜0.33-0.46 × 10 6 mol/km 2/yr for Kamchatka River) due to rock weathering in soils (low-temperature) are entirely consistent with the previously published global weathering laws relating weathering rates of basalts with runoff and temperature. In the Kamchatka River, CO 2 consumption derived from hydrothermal activity represents about 11% of the total HCO 3 flux exported by the river. The high-temperature weathering process explains 25% of the total cationic weathering rate in the Kamchatka River. Although in the rivers non-affected by hydrothermal activity, the main weathering agent is carbonic acid (reflected in the abundance of HCO3- in rivers), in the region most impacted by hydrothermalism, the protons responsible for minerals dissolution are provided not only by carbonic acid, but also by sulphuric and hydrochloric acid. A clear increase of weathering rates in rivers impacted by sulphuric acid can be observed. In the Kamchatka River, 19% of cations are released by hydrothermal acids or the oxidative weathering of sulphur minerals. Our results emphasise the important impact of both low and high-temperature weathering of volcanic rocks on global weathering fluxes to the ocean. Our results also show that besides carbonic acid derived from atmospheric CO 2, hydrochloric acid and especially sulphuric acid are important weathering agents. Clearly, sulphuric acid, with hydrothermal activity, are key parameters that cause first-order increases of the chemical weathering rates in volcanic areas. In these areas, accurate determination of weathering budgets in volcanic area will require to better quantify sulphuric acid impact.

Dessert, Céline; Gaillardet, Jérôme; Dupre, Bernard; Schott, Jacques; Pokrovsky, Oleg S.

2009-01-01

471

PSC 424: Rocks and Minerals  

NSDL National Science Digital Library

This is a webpage designed to give students access to basic information about rocks and minerals. Rocks and Minerals Introduction Video Basic Definitions- Mineral: a solid inorganic substance of natural occurrence Rock: a mixture of minerals Ways to identify a mineral: Hardness Luster (metallic/nonmetallic) Streak Color Rock Song Three basic rock types