Provenance of the Upper Cretaceous Lange-Lysing deep-marine sandstone in the Norwegian Sea: with implication for reservoir quality.

Master's thesis in Petroleum Geosciences EngineeringThe provenance and reservoir properties of Upper Cretaceous Lange-Lysing sandstone in the Norwegian Sea have been determined by using integrated whole-rock geochemical, petrographic and detrital zircon U-Pb age dating by LA- ICP-MS. Three different provenance signatures are revealed within three geographical areas containing the Lange-Lysing succession. They have contributed to significant response on diagenesis, which gives implication for reservoir properties, whereby the petrographic data expose several controls on porosity development, including textural and mineralogical factors. (1) Quartzofeldspathic petrofacies in the Møre Margin are interpreted to have the highest potential as hydrocarbon reservoir due to better sorting and larger grain size, combined with preservation of intergranular and intragranular porosity, not occluded by cement. The zircon grains were derived from felsic sources in the Western Gneiss Region of Baltica, due to a prominent age peak that closely corresponds with the Sveoconorwegian (1000-950 Ma) and the Gothian orogenies (1700-1500 Ma). (2) Sandstone of the quartzolithic petrofacies from the Halten-Dønna Terrace has smaller grain size and is less sorted than the quartzofeldspathic petrofacies, yielding a lower reservoir quality. The detritus is suggested to have been sourced from more mixed ?andesitic-felsic rocks. The zircon grains derived from the Paleozoic Caledonian Nappe Domain of western Baltica and from the Lofoten Islands or Western Tromsø Basement Complex in northern Norway because of a dominance of Early Proterozoic crust-forming zircon grains (1800-1750 Ma) and an Archean component. (3) The main diagenetic features of the quartzarenitic petrofacies in the deeper Vøring Basin includes mechanical and chemical compaction, precipitation and replacement of quartz overgrowth, kaolinite, clay minerals, iron oxide and formation of secondary porosity due to dissolution of labile minerals. Grain coating of authigenic clay minerals exerts a critical control on the reservoir quality as it inhibits quartz cement. The deposits are inferred to have mixed sand distribution from the eastern Greenland and the Norwegian margins based on wide zircon-age spectra with predominance of Early Proterozoic (1900-2100 Ma) and Archean contribution (>2600 Ma). Contradictory to previous studies, the U-Pb analysis of the Lange-Lysing sandstone has proved that Late Archean zircon is present within deposits derived from the Norwegian landmass. Furthermore, the study stresses a strong correlation between provenance, diagenetic products and reservoir qualit

Effect of plant-based feed ingredients on osmoregulation in the Atlantic salmon lens

Lenses of adult Atlantic salmon fed with a plant oil and plant protein-based diet (plant diet) were compared to lenses of fish fed a diet based on traditional marine ingredients (marine diet) with respect to biochemical composition and functionality ex vivo. After 12 months of feeding, plant diet-fed fish had smaller lenses with higher water contents and lower concentrations of histidine (His) and N-acetylhistidine (NAH) than fish fed with the marine diet. Cataract development in both dietary groups was minimal and no differences between the groups were observed. Lens fatty acid and lipid class composition differed minimally, although a significant increase in linoleic acid was observed. The lenses were examined for their ability to withstand osmotic disturbances ex vivo. Culture in hypoosmotic and hyperosmotic media led to increase and decrease of lens volume, respectively. Lenses from plant diet-fed fish were less resistant to swelling and shrinking, released less NAH into the culture medium, and accumulated His and NAH at higher rates than lenses from marine diet-fed fish. Culture in hypoosmotic medium resulted in higher cataract scores than in control and hyperosmotic medium. mRNA expression of selected genes, including glutathione peroxidase 4 and SPARC (secreted protein acidic and rich in cysteine), was affected by diet and osmotic treatment. It can be concluded that lenses of farmed Atlantic salmon are affected by the diet composition, both in biochemical composition and physiological functionality in relation to osmoregulation

APARCH Models Estimated by Support Vector Regression

This thesis presents a comprehensive study of asymmetric power autoregressive conditional heteroschedasticity (APARCH) models for modelling volatility in financial return data. The goal is to estimate and forecast volatility in financial data with excess kurtosis, volatility clustering and asymmetric distribution. Models based on maximum likelihood estimation (MLE) will be compared to the kernel based support vector regression (SVR). The popular Gaussian kernel and a wavelet based kernel will be used for the SVR. The methods will be tested on empirical data, including stock index prices, credit spreads and electric power prices. The results indicate that asymmetric power models are needed to capture the asseymtry in the data. Furthermore, SVR models are able to improve estimation and forecasting accuracy, compared with the APARCH models based on MLE.Masteroppgave i statistikkSTAT399MAMN-STA

Insect-based diets high in lauric acid reduce liver lipids in freshwater Atlantic salmon

We evaluated the effect of a diet containing insect meal and insect oil on nutrient utilization, tissue fatty acid profile and lipid metabolism of freshwater Atlantic salmon (Salmo salar). Insect meal and insect oil from black soldier fly larvae (Hermetia illucens, L.; BSF), naturally high in lauric acid (12:0), were used to produce five experimental diets for an eight‐week feeding trial. 85% of the dietary protein was replaced by insect meal and/or all the vegetable oil was replaced by one of two types of insect oil. A typical industrial diet, with protein from fishmeal and soy protein concentrate (50:50) and lipids from fish oil and vegetable oil (33:66), was fed to a control group. The dietary BSF larvae did not modify feed intake or whole body lipid content. Despite the high content of saturated fatty acids in the insect‐based diets, the apparent digestibility coefficients of all fatty acids were high. There was a decrease in liver triacylglycerols of salmon fed the insect‐based diets compared to the fish fed the control diet. This is likely due to the rapid oxidation and low deposition of the medium‐chain fatty acid lauric acid.publishedVersio

Genome-wide transcription analysis of histidine-related cataract in Atlantic salmon (Salmo salar L)

Purpose: Elevated levels of dietary histidine have previously been shown to prevent or mitigate cataract formation in farmed Atlantic salmon (Salmo salar L). The aim of this study was to shed light on the mechanisms by which histidine acts. Applying microarray analysis to the lens transcriptome, we screened for differentially expressed genes in search for a model explaining cataract development in Atlantic salmon and possible markers for early cataract diagnosis. Methods: Adult Atlantic salmon (1.7 kg) were fed three standard commercial salmon diets only differing in the histidine content (9, 13, and 17 g histidine/kg diet) for four months. Individual cataract scores for both eyes were assessed by slitlamp biomicroscopy. Lens N-acetyl histidine contents were measured by high performance liquid chromatography (HPLC). Total RNA extracted from whole lenses was analyzed using the GRASP 16K salmonid microarray. The microarray data were analyzed using J-Express Pro 2.7 and validated by quantitative real-time polymerase chain reaction (qRT–PCR). Results: Fish developed cataracts with different severity in response to dietary histidine levels. Lens N-acetyl histidine contents reflected the dietary histidine levels and were negatively correlated to cataract scores. Significance analysis of microarrays (SAM) revealed 248 significantly up-regulated transcripts and 266 significantly down-regulated transcripts in fish that were fed a low level of histidine compared to fish fed a higher histidine level. Among the differentially expressed transcripts were metallothionein A and B as well as transcripts involved in lipid metabolism, carbohydrate metabolism, regulation of ion homeostasis, and protein degradation. Hierarchical clustering and correspondence analysis plot confirmed differences in gene expression between the feeding groups. The differentially expressed genes could be categorized as “early” and “late” responsive according to their expression pattern relative to progression in cataract formation. Conclusions: Dietary histidine regimes affected cataract formation and lens gene expression in adult Atlantic salmon. Regulated transcripts selected from the results of this genome-wide transcription analysis might be used as possible biological markers for cataract development in Atlantic salmon