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<p>Strandlinjen i Sverige har sedan den senaste inlandsisen präglats av isostatisklandhöjning. Höjningen var som kraftigast straxt efter deglaciationen men verkar påtagligt än idag i landets norra delar, framförallt Ångermanland och Västerbotten, medan rörelsen minskat i landets södra delar där den är liten eller avtagit helt. Strandförskjutning är resultatet av isostatisk landhöjning och eustatisk havsytenivåförändring. För att rekonstruera strandförskjutningens utveckling upprättas strandförskjutningskurvor. Kurvan är således resultatet av landhöjning och havsnivåförändringar i meter som en funktion av tiden. Då den isostatiska landhöjning påverkar strandförskjutningsförloppet både i nord-sydlig samt öst-västlig riktning med varierande storlek i olika delar av landet, bör områden modelleras utifrån lokala förutsättningar för att uppnå en så korrekt detaljnivå som möjligt.</p><p>Examensarbetes syfte är att belysa paleogeografiska förändringar i östra Svealand under de senaste 7000 åren. Information har hämtats från såväl arkeologiska som geologiska källor, såsom strandnära bosättningar och isolerade sjöar. Genom att använda geografiskt läge, nuvarande höjd över havet och ålder, kunde en trendyta anpassas för att beräkna en synkron forntida strandlinje för valfri tidpunkt inom hela undersökningsområdet.</p><p>Trendytan skapades med hjälp av multivariat regressionsanalys vilket resulterade i en andragradsekvation baserad på åldern i kvadrat, vilket indikerar att hastigheten av strandförskjutningen har varierat med tiden, i detta fall avtagit med tiden. Ytan visade på ojämn isostasi i både nord-sydlig och öst-västlig riktning med högst höjning i nordväst och lägst i sydost.</p><p>Tidigare studier har påvisat indikationer på transgressiva förlopp söder om Mälardalen under senaste 7000 åren. Inga sådana trender kunde dock identifieras genom denna matematiska funktion då detta kräver fördjupade sedimentstratigrafiska studier.</p>

<p>The paleoglaciology of the Tibetan Plateau is still largely unexplored, despite its importance for regional and global climate reconstructions. In this thesis a comprehensive glacial geological record is presented from an extensive part of the northeastern Tibetan Plateau centred on the Bayan Har Shan. Glacial reconstructions for this region range from restricted mountain glaciers through the intermediate-size regional-scale Huang He ice sheet to a plateau-scale Tibetan ice sheet. To provide a robust basis for glacial reconstructions, this thesis provides conclusions based on two principle methods, remote sensing and field studies. The remote sensing of a 90 m resolution digital elevation model and 15- and 30 m resolution satellite imagery renders a detailed data set with complete spatial coverage of large- and medium-scale glacial landforms, and large-scale plateau geomorphology. Observations from fieldwork campaigns add detailed point information for the distribution of glacial deposits. Geomorphological glacial traces such as glacial valleys, glacial lineations, marginal moraines, meltwater channels, and hummocky terrain occur frequently in elevated mountain areas, indicating former alpine-style glaciations. Glacial deposits in the form of till, erratic boulders, and glaciofluvial sediments are common in areas with mapped glacial landforms, but also beyond, in areas lacking large-scale glacial landforms. For extensive plateau areas in-between formerly glaciated mountain blocks, there is a striking absence of glacial landforms and sediments, indicating that these areas, perhaps, never were ice covered. Interestingly, glacial deposits occur further away from the mountain blocks than the large- and medium-scale glacial landforms, indicating insignificant erosion beneath the maximum ice covers close to their margins.</p><p>The large-scale geomorphology of the northeastern Tibetan Plateau is characterised by a low-relief plateau surface with glacial valleys in elevated mountain blocks and marginal steep V-shaped valleys. This geographical distribution indicates a dominance of glacial erosion in the elevated mountain areas and a dominance of fluvial erosion along the steep plateau margins, dissecting a relict plateau surface. The outline of the relict plateau surface mimics the proposed outline of the Huang He ice sheet, suggesting that the inferred ice sheet may represent a misinterpreted relict surface with scattered glacial traces.</p><p>In conclusion, the glacial geology examined in the Bayan Har Shan region is consistent with paleo-glaciers of varying extent restricted to elevated mountain areas. Even though extensive icefields/ice caps were centred on discrete mountain areas, there is no indication that these ice masses merged but rather that they were separated from each other by unglaciated plateau areas. The presented glacial geological record will be used in further studies towards a robust paleoglaciological reconstruction for the northeastern Tibetan Plateau.</p>

<p>Detta arbete har utförts under 10 veckor och har resulterat i en gemensam digital karta över Falun, Borlänge och Säters kommun. För att lyckas komma fram till resultatet har jag utfört en rad analyser av ingående data, och likriktat data så att framställandet av en gemensam karta blivit möjligt. Arbetet har varit indelat i två delar, insamling och likriktning av data samt kartografisk anpassning av data. Den första delen av examensarbetet har tagit upp den största delen av tiden, medan betydligt mindre tid lagts på den kartografiska anpassningen. Data som använts har samlats in från kommunernas primärkartor, Lantmäteriets fastighetskarta samt Vägverkets Nationella vägdatabas (NVDB). Programvaran FME från Safe Software har varit ett mycket bra verktyg för att likrikta data, och har använts i stor omfattning. De rutiner för uppdatering av data som föreslagits, har också tagits fram med denna programvara som grund. För att studera och kontrollera datas utseende har ArcGIS från ESRI använts. ArcGIS har dessutom utnyttjats för den kartografiska anpassningen. Den framtagna kartan gör inga som helst anspråk på att vara topologiskt korrekt, även om topologin i vissa avseenden beaktats. Fokuseringen har legat på att få fram en tydlig och enkel karta, som efter mindre justering skall kunna användas av olika intressenter förutom Räddningstjänsten DalaMitt. Exempel på dessa intressenter kan vara andra verksamheter inom kommunen såsom gatukontoret, eller externa intressenter som önskar en gemensam karta för sin verksamhet.</p> / <p>This project has been carried out during 10 weeks, and has resulted in a common digital map containing the municipalities of Falun, Borlänge and Säter. To reach the desired result I have had to carry out a number of analyses on the ingoing data, and standardize the data to make the completion of a common map possible. The project has been divided into two large parts, collection and standardization of data, and cartographic adaptation of data. The first part has demanded most time, while considerably less time has been spent on the cartographic adaptation. Data that has been used was collected from the municipalities’ primary maps, the Swedish Land surveying’s parcel map and the Swedish National Road Administration’s National road database (NVDB). The software FME from the manufacturer Safe Software has been a very helpful tool to standardize data, and has been used in a large scale. The routines for updating the data that is suggested, has also been developed with the software. To study and control the look of data, the software ArcGIS from ESRI has been used. ArcGIS has also been used for the cartographic adaptation. The developed map doesn’t claim to be topological correct, even though the topology has been considered in some ways. The focus has been to develop a map that is clear and simple, and that after minor adjustments can be used by other actors other than the Rescue Service of Dala-central. Example of these actors can be other activities within the municipalities, such as the street offices, or external actors who wish to use a common map in their activities.</p>

Structure of the Roberts Mountains allochthon in the Three Bar Ranch Quadrangle, Roberts Mountains, Eureka County, Nevada

Diss.--Hamburg, 1965. / Part of illustrative matter in pocket. Bibliography: p. 224-226.

Thesis--Münster. / At head of title: Geographie. Vita. Includes bibliographical references (p. 164-168).

Variability in climate and wildfire activity are inextricably linked through complex and often poorly understood processes. The studies presented in this dissertation examine fire-climate relationships across the southwestern United States at different temporal and spatial scales. Collectively, they identify that low-frequency and high-frequency changes in climatic variables important to wildfire are connected through teleconnection patterns originating in the tropical and extratropical Pacific Ocean (El Nino-Southern Oscillation [ENSO] and Pacific Decadal Oscillation [PDO]). Variability in precipitation years prior to a wildfire season appears to affect the overall number of fires and total area burned by either promoting or limiting the growth of fine fuels and also controlling moisture levels in heavy fuels. The same mechanisms (ENSO & PDO) that play a role in precipitation variability across the Southwest also appear to modulate the frequency of extreme fire weather events during the spring fire season. Identifying links between high and low frequency climatic variables important to wildfire variability provides additional insight into the complex mechanisms that link wildfire and climate. The results of this dissertation will aid in improving wildfire planning efforts that extend seasons to decades into the future.

The buildup of the cosmogenic nuclides ³He and ²¹Ne in surficial rocks permit exposure ages and erosion rates to be estimated. This dissertation extends the cosmogenic exposure technique to garnets, plagioclase with significant nonspallation ²¹Ne components, and alluvial fill terraces. Garnets from Nanga Parbat, Pakistan have low nucleogenic ³He and moderate radiogenic ⁴He concentrations. ³He exposure ages from garnets in glacial erratics indicate glacial advances at Nanga Parbat at about 16 ka and 55 ka. 3He in alluvial garnets suggests that denudation in small unglaciated basins proceeds 5 to 7 times slower than glacial erosion, and 10 to nearly 100 times slower than regional rock exhumation and surface uplift. Rocks older than several million years possess nucleogenic and mugenic ²¹Ne and ³He components that must be resolved for accurate exposure ages. These nonspallation components in plagioclase and clinopyroxene from the Miocene Columbia River Basalt Group are best isolated with shielded samples. Analyses of ⁴He, U, Th, and Li systematically underpredict the amount of nonspallation ²¹Ne and ³He present in shielded samples, probably because of mugenic production. Step heating experiments suggest that ²¹Ne diffusive loss from plagioclase is possible, but most samples do not exhibit such ²¹Ne loss. The ratio of ²¹Ne in plagioclase and ³He in clinopyroxene is generally constant after correction for the nonspallation component, indicating that little or no ²¹Ne loss has occurred. The last highly erosive floods at Grand Coulee occurred at about 21 ka, early in the cycle of Missoula flooding. Nuclide inheritance must be resolved for accurate exposure ages of stream fill terraces. Depth profiles of cosmogenic ²¹Ne in quartz from terraces on the Pajarito Plateau, northern New Mexico resolve nuclide inheritance. Three patterns of depth profiles are recognized: (1) downward decreasing; (2) downward increasing; and (3) uniform; types 2 and 3 are associated with cumulate deposits and bioturbation, respectively. Inheritance corrected exposure ages for the terraces agree with independent radiocarbon and soil development ages. Denudation rates estimated from the profiles are higher for fill terraces than for straths.

The scientific literature regarding the origin of granite landscapes is dominated climatic geomorphologists who argue that these landscapes are the products of deep weathering of highly jointed granite under tropical climates, or structural geomorphologists who insist that structure and lithology are of greater importance than climate. This study examines the origin of three distinct landscapes found on three granite pediments along the western and northern margins of the Santa Catalina Mountains of southeastern Arizona. The Oracle granite pediments are dominated by boulder inselbergs, those of the Catalina granite by domed inselbergs and platforms, while Wilderness Suite granite pediments are sloping shelves that lack these characteristic landforms. These granites have a similar late Cenozoic history of weathering and erosion, but differ in structure, lithology, and age. Field evidence and laboratory analysis support the arguments of structural geomorphologists and indicate that the model presented by climatic geomorphologists is not valid for the study area. The landforms found here appear to be the products of surface weathering and fluvial erosion guided by joints and lithology.