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Oslo, Norway

Killops S.,Applied Petroleum Technology AS | Stoddart D.,Lundin Norway AS | Stoddart D.,Royal Dutch Shell | Mills N.,Applied Petroleum Technology AS
Organic Geochemistry | Year: 2014

Conventional biomarker age indicators may not always give conclusive inferences for the age of an oil's source rock, particularly with regard to condensates, in which most of the key biomarkers are often too sparse to determine. It is possible that other compounds, reflecting changes in primary producer assemblages or depositional environment, can provide age indications in basins that have experienced a progressive change in conditions. The Norwegian Barents Sea provides an opportunity to evaluate this approach, although the gradual changes are punctuated by intervals of stratification, OAEs and extinctions. Partial least squares analysis was used to identify a number of apparently suitable parameters, to establish an age calibration from source rock extracts and then to apply it to a variety of oils and condensates from the Barents Sea. The resulting source age inferences are consistent with conventional age parameters for the normal oils, providing a degree of confidence in their applicability to the problematic condensates. In the main part of the Hammerfest Basin, oils of Jurassic origin dominate, whereas contributions from Triassic sources are suggested towards the margins, particularly in pre-Jurassic reservoirs. To the east, on the Norsel High and in the Nordkapp Basin, the main oil sources are suggested to be Early Triassic, although a Palaeozoic, possibly Permian, source is likely on the margin of the Finnmark Platform in well 7128/4-1. Among the novel parameters, the relative abundances of phytanyl arenes and diadrimanes appear to be controlled by diagenetic conditions. © 2014 Elsevier Ltd. Source

Al Dushaishi M.F.,Missouri University of Science and Technology | Nygaard R.,Missouri University of Science and Technology | Hoel E.,Lundin Norway AS | Hellvik S.,NOV Dynamic Drilling Solutions | Andersen M.,NOV Dynamic Drilling Solutions
Proceedings of the International Conference on Offshore Mechanics and Arctic Engineering - OMAE | Year: 2015

Severe drill stem vibrations could leads to excessive damage to the bottom hole assembly causing an increase in nonproductive time. Different drill stem vibrations models are used to predict and avoid resonance regions by optimizing the selection of bottom hole assembly components and operating parameters such as weight on bit, and surface RPM. In addition to avoid the resonance regions, specialized tools have been developed to reduce vibrations. However a complete understanding on how to mitigate vibration and its effect on drilling performance is still lacking. This study investigates the cause of drill stem vibrations, its effect on drilling performance, and the effect of including vibration reductions tools in the bottom hole assembly design in several recent drilled wells in the North Sea. Vibration damping tools used in this study were able to reduce both lateral and torsional drill stem vibration compared to a well with no vibration damping tool. Torsional drill stem vibrations tend to increase through rich sand zones causing an increase in lateral vibrations. The impact drill stem vibrations have on drilling performance was identified through rate of penetration. As lateral vibration intensity increases, instantaneous rate of penetration decreases. © 2015 by ASME. Source

Lundmark A.M.,University of Oslo | Saether T.,Depotgata 37A | Sorlie R.,Lundin Norway AS
Geological Society Special Publication | Year: 2014

The age and tectonic significance of two basement granitoids cored on the Utsira High, Viking Graben, North Sea, are constrained by zircon LA-ICPMS data. Syenite in well 25/10-2R is dated to 482±2 Ma, with εHf(482) values from 24.4 to 25.8, and granite in well 16/1-12 yields an age of 436±3 Ma with εHf(436) values from +3.7 to 20.5. The evolved Hf-signature of the syenite demonstrates 482 Ma reworking of Palaeoproterozoic-Archaean crust, interpreted to reflect Taconian-Grampian orogenesis. New and recently published data from the offshore Caledonides allow a first-order correlation of the Utsira High basement with the surrounding on-and offshore Caledonides. The Utsira High occupies a similar position with respect to Dalradian rocks as the Scottish Midland Valley terrane. Geophysical data indicate a volcanic arc beneath the East Shetland Basin, forming a northwards continuation of the Utsira High basement. We propose that the offshore volcanic arc segments represent the northeastern continuation of the Scottish Grampian orogen across the Mesozoic North Sea rift. A north-striking terrane boundary fault is proposed to separate the volcanic arc from the East Shetland Platform and merge northwards with the offshore extension of the Great Glen Fault-Møre Trøndelag Fault Complex. © The Geological Society of London 2014. Source

Belkina N.,Lundin Norway AS | Sarkova O.,IS Systems
Polar Geography | Year: 2014

Norwegian–Russian cooperation on exploration and production of petroleum resources in the Barents Sea implies joint planning of the preparedness and response to potential oil spills. The joint planning calls for a good understanding of oil spill response (OSR) regulatory regimes in neighboring countries. The paper presents an initial effort to compare the national regulatory approaches of Norway and Russia to OSR. The research is based on an analysis of primary legislative documents and interviews with oil companies, oil spill responders, and relevant national authorities. The research concludes that the Russian legislative framework for OSR can be characterized as prescriptive, while the Norwegian OSR regulations are of a performance-based type. In Norway, OSR capacity is based on the environmental risk assessment, and there are stipulations in the regulations concerning adapting response equipment and operations to the type of pollution and the site-specific conditions of each facility. Russian regulations stipulate that oil spill preparedness shall be based on the risk assessment but, at the same time, strictly prescribe volumes of spills and time to stop oil spreading without attention to specific site conditions. The research reveals the disadvantages of the prescriptive approach and suggests considering Norwegian regime as a model for adapting more flexible performance-based approach. © 2014 Taylor & Francis Source

Horn H.,Ferrx AS | Saasen A.,University of Stavanger | Skogvang A.,Lundin Norway AS
SPE/IADC Drilling Conference, Proceedings | Year: 2016

The paper presents a new and novel non-destructive method for measuring deterioration and cracks in steel structures. Results from stress and fatigue tests with different full scale structures are presented and related to real applications with respect to life-time prediction. Conventional cyclic loading test of riser-pipe elements are documented herein for confirmation of the method. The subject method functions as follows: The material properties magnetic permeability and electrical conductivity, and changes in these, are determined by analyzing the measured voltage response to injected electric pulses. The response is transient voltage drop signals, measured under various conditions, and is the basis for calculating parameters representing the stress, fatigue and crack nucleation and crack development in the materials. The degree of material degradation can be used to calculate operational lifetime. The method has been tested and verified for different types of stress and fatigue loads in different steel alloys. High sensitivity to elastic stress and early detection of permanent changes for high-cycle fatigue testing have been demonstrated with fatigue tests of workover riser pipes. High sensitivity to remanent stress, i.e. the steel's ability to "remember" stress (elastic) is a feature that is proportional to the maximum stress occurred since last measurement. On risers, measurement devices can be installed to give the actual condition of the steel for the most exposed locations. Additionally, this information can be used to calibrate the mathematical models for estimating the condition of the whole riser in order to reduce the uncertainty of estimates. Copyright 2016, IADC/SPE Drilling Conference and Exhibition. Source

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