World-class outcrops of an outermost erg-margin can be observed within the Middle Jurassic Entrada Sandstone near Capitol Reef National Park, Utah. These erg-margin deposits contain isolated reservoir quality sandstone bodies that transition into a muddy tidal flat facies. These high quality reservoirs are dominated by eolian-influenced facies interbedded with sandy interdune facies. They are sealed vertically by muddy and silty facies of associated tidal flat deposits that act as excellent stratigraphic traps in the subsurface. A variety of approaches were used to characterize these Entrada erg-margin reservoirs including: annotated panoramas of outcrops, measured sections, scintillometer measurements of field sections, facies analysis, 2D high-resolution shallow seismic surveys, porosity and permeability analysis, and sedimentary petrography. Logs from the North Hill Creek/Flat Rock gas field were analyzed and correlated to the outcrop study. Eolian dune facies, along with an upper ripple laminated facies representing interdune deposits, display the highest porosities and permeabilities and are volumetrically the most important facies of the reservoir quality sandstones. Baffles and possible barriers within the sandstone bodies are limited to quartz filled fractures, deformation bands, silty and muddy interdune facies, and first order bounding surfaces. Many of the sandstone bodies within the outcrop belt are genetically related and in communication with each other. This relationship results from dune complex migration to the south and up section over time. Stratigraphic climb can potentially be imaged seismically and may serve as a key indicator of eolian dune complexes in the subsurface. The volumetric size of one of these complexes is estimated around 470 million cubic feet. Smaller outcrop sandstone bodies were often found to be isolated from the large dune complexes and ranged down to 1 million cubic feet in size.

Let G = (V, E) be an arbitrary graph, and consider the following game. You are allowed to buy as many tokens as you like, say k tokens, at a cost of $1 each. You then place the tokens on some subset of k vertices of V. For each vertex of G which has no token on it, but is adjacent to a vertex with a token on it, you receive $1. Your objective is to maximize your profit, that is, the total value received minus the cost of the tokens bought. Let B(X) be the set of vertices in V - X that have a neighbor in a set X. Based on this game, we define the differential of a set X to be ∂ (X) = |B(X)| - |X|, and the differential of a graph to equal the max{∂(X)} for any subset X of V. In this paper, we introduce several different variations of the differential of a graph and study bounds on, and properties of, these novel parameters.

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When designing or reviewing control systems, it is important to understand the limitations of the system's design. Many systems today are designed using numerical methods. Although the numerical model may be controllable, stabilizable, or stable, small perturbations of the system parameters can result in the loss of these properties. In this thesis, we investigate these issues for finite element approximations of a thermal convection loop. / Master of Science

This dissertation consists of three essays that examine the impact of various trade policies on the extensive (new trading relationships) and intensive (increase in trade of existing relationships) margins of trade, whereas past studies have been limited to aggregate trade flows. An inquiry into the extensive and intensive margins of trade reveals that total aggregate trade masks the heterogeneous trade creating effect of policy variables. Furthermore, this dissertation also takes into account the econometric issues that have plagued the traditional empirical model that analyzes the impact of these policies on trade. The first chapter examines the impact of hosting and bidding for mega-events on exports. Rose & Spiegel (2011b) find that hosts and unsuccessful bidders (candidates) experience a similar positive impact on total aggregate exports. They attribute the Olympic effect to the signal a country sends when bidding to host the games. This chapter inquires whether this Olympic signal leads to new trading relationships or an increase in trade in existing relationships. The results indicate that only hosts (not candidates) experience a permanent increase in exports at the intensive margin. While hosting the Olympics is consistently correlated with a permanent deepening of existing trade relationships, it is at the expense of the number of trading relationships. The second chapter examines the impact of the World Trade Organization (WTO) membership on the extensive and intensive margin of imports. Accounting for several estimation issues that have plagued the literature, results indicate that the benefit of the WTO is realized entirely through the extensive margin. The results are in line with the literature that attributes WTO to reducing market uncertainty through tariff binds rather than reduction, thus increasing entry in the export market even when the applied protection is unchanged. The third chapter examines the impact of fiscal episodes (fiscal stimuli and consolidation) on the extensive and intensive margins of exports. The results indicate that fiscal consolidation leads to an increase in total exports, while a fiscal stimulus leads to a decrease in total exports. Furthermore, fiscal consolidation leads to an increase in exports solely through the extensive margin.

A study of the distribution of diagenetic alterations and their impact on reservoir-quality evolution in four deep-water turbidite successions (Cretaceous to Eocene) from basins in active (foreland) and passive margins revealed the impact of tectonic setting, depositional facies, and changes in the relative sea level. Diagenetic modifications encountered in the turbiditic sandstones from the passive margin basins include dissolution and kaolinitization (kaolin has δ18OV-SMOW = +13.3‰ to +15.2‰; δDV-SMOW = -96.6‰ to -79.6‰) of framework silicates, formation of grain coating chloritic and illitic clays, cementation by carbonates and quartz, as well as the mechanical and chemical compaction of detrital quartz. Kaolinitization, which is most extensive in the lowstand systems tracts, is attributed to meteoric-water flux during major fall in the relative sea level. Preservation of porosity and permeability in sandstones from the passive margin basins (up to 30% and 1 Darcy, respectively) is attributed to the presence of abundant rigid quartz and feldspar grains and to dissolution of carbonate cement as well as mica and feldspars. Diagenetic modifications in turbidites from the foreland basins include carbonate cementation and mechanical compaction of the abundant ductile rock fragments, which were derived from fold-thrust belts. These diagenetic alterations resulted in nearly total elimination of depositional porosity and permeability. The wide range of δ13CV−PDB values of these cements (about -18‰ to +22‰) in passive margin basins is attributed to input of dissolved carbon from various processes of organic matter alterations, including microbial methanogenesis and thermal decarboxylation of kerogen. The narrower range of δ13CV−PDB values of these cements (about -2‰ to +7‰) in the foreland basins suggests the importance of carbon derivation from the dissolution of carbonate grains. The generally wide range of δ18O values (about -17‰ to -1‰) of the carbonate cements reflect the impact of oxygen isotopic composition of the various fluid involved (including marine depositional waters, fluxed meteoric waters, evolved formation waters) and the wide ranges of precipitation temperatures. Results of this study are anticipated to have important implication for hydrocarbon exploration in deep-water turbidites from passive and active margin basins and for pre-drilling assessment of the spatial and temporal distribution of reservoir quality in such deposits.

The continental margin off Nova Scotia (the Scotian margin) forms the northern edge of the North American Basin. The Cenozoic stratigraphy and geological history of the outer margin is not well known. This study examines aspects of the Upper Cretaceous-Cenozoic geological history of the outer Scotian margin addressing the following objectives: 1) determine the geological history of a large deep-water depocenter, 2) investigate processes that led to deep-water unconformity formation in the study area, 3) determine the role of deep-ocean circulation in margin evolution, 4) examine the effects of morphological heritage on subsequent depositional patterns. High quality 2-D and 3-D seismic reflection data along with lithostratigraphic and biostratigraphic data from hydrocarbon exploration wells provide the basis for this investigation. The seismic stratigraphy of a large deep-water depocenter along the western Scotian margin was broadly divided into four units. Unit 1 (Upper Cretaceous-Upper Eocene) is attributed to repeated, widespread erosion events interspersed with periods of hemipelagic and pelagic, carbonate-rich sedimentation. Unit 2 (Lower Oligocene-Middle Miocene) consists of a variety of seismic facies overprinted by dense, small-offset faults. Unit 3 (Middle Miocene-Upper Pliocene) is dominated by sediment drift deposition. Unit 4 (Upper Pliocene-present) is characterized by channel development and gravity flow deposition. The processes that led to regional seismic stratigraphic horizons were complex. Both large mass-wasting events and along-slope bottom currents contributed to the formation of unconformities in the study area. Most of the succession preserved in the depocenter belongs to seismic units 2 and 3. These deposits are mainly confined to the area seaward of the Abenaki carbonate bank and landward of shallow salt structures below the slope. Locally, however, modification of the slope profile through mass-wasting and bottom current processes greatly influenced subsequent depositional patterns. The Cenozoic geological evolution of the study area was strongly affected by northeast-to-southwest flowing bottom currents. The earliest indication of bottom current activity was in the Eocene. Upper Miocene and Pliocene sediment drifts represent >50% of the preserved stratigraphic section in the thickest part of the depocenter. It is clear that along-slope sedimentary processes were far more important in shaping the margin than previously understood.

A high-resolution multi-proxy reconstruction of the Arabian Sea Summer Monsoon (ASSM) intensity over the past 90,000 years has been determined using two marine sediment cores: one from the Somali margin and one from the Indian margin. This reconstruction indicates that changes in monsoon- induced upwelling, primary productivity and denitrification have varied in synchrony with Dansgaard-Oeschger (D-O) cycles. Increased monsoon intensity correlates with warm climate events (interstadials) and decreased monsoon intensity, which coincides with stadials and Heinrich Events, is confirmed by elevated dust concentrations in the marine cores. A comparison of the Somali and Indian margin cores with previously reported studies from the Northern and Western Basin allows the identification of discrete sediment signals from the Indus River, the Arabian Peninsula and from local riverine runoff. Sedimentary deposition on the Indian margin during interglacials is dominated by local terrestrial runoff, whereas during glacial periods increased dust input from the Arabian Peninsula is evident. Both signals are related to changes in the intensity of the ASSM. Monsoon intensity has decreased during the Holocene as the Intertropical Convergence Zone (ITCZ) has moved to a more southerly position. The ASSM-ITCZ relationship (increased ASSM intensity and a northern ITCZ, decreased ASSM intensity and a southern ITCZ) has remained consistent over the last glacial cycle suggesting that global millennial scale climatic variability is in part driven by modulations in tropical hydrological cycle. This ASSM reconstruction provides evidence that rearrangements in the tropical convection system affected atmospheric dust concentrations as well as the concentration and location of atmospheric water vapour. In addition to modulating terrestrial and marine emissions of greenhouse gases, variation in the tropical hydrological cycle provides a mechanism of amplifying and perpetuating millennial-scale climatic changes.

Abstract This research examines the lower edge of arable land in cultivating littoral land and its effects on spring sowing Central Ostrobothnia and in the southern areas of Northern Ostrobothnia. This doctoral thesis develops methods to raise the lower edge of arable land in low littoral land. The methods are based on contribution margin, the gross profil of yield, the relocation of dry margin and the realigning of littoral land's area descriptor. In addition, outdated littoral land profil and loss evaluation criteria are renewed. The objective of the research is to decrease environmental damages and to improve cultivation. Another objective in raising the lower edge of arable land is to enhance the forming of protective noncultivated belts. Ten lakes from the hydrologic areas of the rivers Perhonjoki, Kalajoki and Pyhäjoki were chosen for the research, one half of them were in their natural state and the other half were regulated. The research consisted of comparing the sowing dates and patch yields (moisture content 14%) of the sample parcels (104 observations) chosen from littoral land around the lakes to the corresponding figures of sample parcels selected from outside the areas influenced by water level variation. The findings are from 1985–1991 and 1996–1998. The cultivated plants were barley, oats and hay. The sample area research was completed with interviews. Furthermore, the research examined the dependence of air pore space of the soil cultivation layer on the dry margin. The research result indicate that the lower edge of arable land has to be raised, for lakes in their natural state the rise would be on average 35 ± 4 cm (67 observations) and for regulated lakes on average 39 ± 4 cm (61 observations). The minimum dry margins required by soil cultivation and sowing will be 69 ± 5 cm (67 observations) and 78 ± 5 cm (61 observations). Thus, the lowest part of the waterfront will not be cultivated anymore. The contribution margin of the field is not changed. Sowing can be done earlier and air pore space and viability increase. The condensation detriment of the soil cultivation layer, the workload needed for cultivation and the nutrient load in hydrologic areas will be decreased. Measuring and locating protective non-cultivated belts becomes easier. The state of environment is improved. The evaluation of profit and loss is modernized. / Tiivistelmä Tutkimuksessa tarkastellaan rantamaiden viljelyksessä pellon alarajaa ja sen vaikutuksia kevätkylvöihin Keski-Pohjanmaalla ja Pohjois-Pohjanmaan eteläisellä osalla. Työssä kehitetään katetuottoon, sadon bruttotuottoon, kuivavaran siirtoon ja rantamaan pinta-alan kuvaajan oikaisuun perustuvat menetelmät pellon alarajan määrittämiseksi alavilla rantamailla. Samoin pyritään nykyaikaistamaan rantamaiden hyödyn- ja vahingonarviointia. Tutkimuksen tavoitteena on vähentää viljelyn aiheuttamia ympäristöhaittoja sekä parantaa samalla itse viljelyä. Pellon alarajan määrittämisen yhteydessä on tavoitteena edistää myös suojavyöhykkeiden perustamista. Kohdejärvinä oli Perhonjoen, Kalajoen ja Pyhäjoen vesistöjen kymmenen järveä, joista puolet oli luonnontilaisia ja puolet säännösteltyjä. Järvien rantatiloilta valittujen koelohkojen (104 kpl) kylvöaikoja ja ruutusatoja (kosteuspitoisuus 14 %) verrattiin vedenkorkeuksien vaihteluista riippumattomien vertailulohkojen vastaaviin arvoihin. Havaintovuodet olivat 1985–1991 sekä 1996–1998. Viljelykasveja olivat ohra ja kaura sekä heinä. Koealuetutkimuksia täydennettiin haastatteluina. Lisäksi tarkasteltiin muokkauskerroksen ilmahuokostilan riippuvuutta kuivavarasta määritettynä järven vedenkorkeudesta. Tutkimustulosten mukaan pellon alarajaa on korotettava nykyisestään luonnontilaisilla järvillä keskimäärin 35 ± 4 cm (n = 67) ja säännöstellyillä järvillä keskimäärin 39 ± 4 cm (n = 61). Kylvön vaatimat kuivavarat määritettyinä järvien vedenkorkeuksista tulevat olemaan vastaavasti 69 ± 5 cm (n = 67) ja 78 ± 5 cm (n = 61). Tällöin rantalohkon alavimmalta osalta viljely poistuu. Pellon katetuotto ei muutu. Kylvö aikaistuu, ilmahuokostila kasvaa ja kulkukelpoisuus paranee. Muokkauskerroksen tiivistymishaitta ja viljelyn työnmenekki sekä vesistöön kohdistuva ravinnekuormitus vähenevät. Suojavyöhykkeiden mitoitus ja sijoitus helpottuvat. Ympäristön tila paranee. Hyödyn ja vahingon arviointi nykyaikaistuu.

Many studies consider the potential for preferential trade agreements (PTAs) to have differing effects on trade. Kohl (2014) and Baier et al. (2019) show that some PTA’s promote trade while the majority of PTAs have no significant effect. Some even lower trade. Why do these differing cases arise? One possibility is that the effects of trade agreements depend on specific provisions – provisions that differ across agreements. Another possibility is the potential for PTAs to impact trade differently depending on the presence of certain bilateral characteristics between trading nations such as physical distance or metaphorical types of distance such as culture or language. In my dissertation, “Heterogeneous Effects of Trade Agreements on Trade,” we explore these two avenues separately.In the first chapter we consider if differences in the prevalence of corruption between members of a PTA make trade agreements more or less effective at boosting trade. Such differences could create more uncertainty that limits the potential for trade even if a trade agreement lowers barriers, implying that such agreements will not boost trade. On the other hand, trade agreements could be most effective in such disparate countries. Not only might trade agreements remove barriers used by corrupt officials to extort firms, but a trade agreement could reduce the uncertainty of operating in a different business environment by establishing rules and regulations. Results in this paper are allowed to differ across several dimensions, including extensive versus intensive margin, whether the exporter or importer is more corrupt, and between South-South and South-North trade. Using a gravity model of trade spanning a panel of countries from 1996 to 2017, we find that PTAs increase trade more along the intensive margin when importing countries are more corrupt but boost trade more along the extensive margin when exporting countries are more corrupt. Results are stronger for trade between South-South (S-S) countries than between North-South (N-S) countries. Chapter two examines how specific provisions within trade agreements – particularly, provisions regarding environmental standards – affect trade between members and non-members. While there is a rising trend to incorporate different types of environmental provisions in preferential trade agreements (PTAs), few studies took explicit steps to assess the trade consequences of environmental provisions in PTAs. This paper employs a gravity model over the period from 1984 to 2016 and uses a new detailed dataset on a broad range of environmental provisions in PTAs to fill the gap in the literature by looking at possible trade diversion effects from trade agreements with deep environmental clauses. We follow Mattoo et al. (2017) and construct an index that captures importers’ average depth of trade agreements with the rest of the world where depth is taken as the extent that environmental provisions are covered. The inclusion of this depth variable allows us to see if any trade diversion effect arises from trade agreements with deep environmental provisions. We specifically focus on exporters with low environmental standards, as those are the countries that are likely to “host” trade in environmentally unsustainable goods. We also differentiate between different types of environmental policies and concentrate on trade in “dirty” products. Our results suggest that environmental provisions in PTAs are an effective tool of promoting environmentally sustainable trade in the world, as these types of policies tend to reduce “dirty” trade even with non-member nations. Finally, the third chapter considers the heterogeneous design of PTA’s more broadly, looking at the trade effects of different policy areas within trade agreements, while differentiating their impact on trade in new product varieties of goods versus trade in existing products. We specifically focus on 18 “core” provisions that Hofmann et al. (2019) mark as most economically relevant policies. We further distinguish three types of policies within the “core” group of provisions, namely: i) provisions that directly liberalize trade through either reduction in tariffs or simplification of standards, ii) policies that enable signatory nations to compete on equal grounds, and iii) provisions that specify the rules of investment. Previous studies that consider the effects of trade agreements on the margins of trade have either focused on the effects of different types of PTAs, rather than specific policies, or used limited data and outdated methodologies. We are contributing to the literature by assessing the impact of different groups of policies on the margins of international trade using a highly disaggregated dataset covering a large number of countries and years. We also employ Factor Analysis to check robustness of our findings using regular count indices. Our results indicate that provisions that tend to reduce barriers to trade through either simplification of standards or reduction in monetary charges tend to increase trade in existing varieties of goods, while the effect of investment provisions is either insignificant or might actually lower trade.