Time Operation Research Articles

Space-time from Collapse of the Wave-function

Abstract We propose that space-time results from collapse of the wave function of macroscopic objects, in quantum dynamics. We first argue that there ought to exist a formulation of quantum theory which does not refer to classical time. We then propose such a formulation by invoking an operator Minkowski space-time on the Hilbert space. We suggest relativistic spontaneous localisation as the mechanism for recovering classical space-time from the underlying theory. Quantum interference in time could be one possible signature for operator time, and in fact may have been already observed in the laboratory, on attosecond time scales. A possible prediction of our work seems to be that interference in time will not be seen for ‘time slit’ separations significantly larger than 100 attosecond, if the ideas of operator time and relativistic spontaneous localisation are correct.

Alpha spectroscopy backgrounds at Lawrence Livermore National Laboratory: technical equivalency for backgrounds with blank plates versus backgrounds with no plates

Alpha spectroscopy chamber backgrounds are routinely measured using blank plates. Operator time spent moving blank plates in and out of chambers is significant. If chamber backgrounds are measured in empty chambers, time spent moving blank plates can be reclaimed for other uses. This study compares results of chamber backgrounds measured with and without plates. Five hundred fourteen chamber backgrounds measured with plates are paired with 514 chamber backgrounds measured without plates. The total counts within 13 spectral regions of interest are compared statistically. Chamber backgrounds measured without blank plates are found statistically equivalent to chamber backgrounds measured with blank plates.

Quasi-automatic 3D reconstruction of the full spine from low-dose biplanar X-rays based on statistical inferences and image analysis.

To design a quasi-automated three-dimensional reconstruction method of the spine from biplanar X-rays as the daily used method in clinical routine is based on manual adjustments of a trained operator and the reconstruction time is more than 10min per patient. The proposed method of 3D reconstruction of the spine (C3-L5) relies first on a new manual input strategy designed to fit clinicians' skills. Then, a parametric model of the spine is computed using statistical inferences, image analysis techniques and fast manual rigid registration. An agreement study with the clinically used method on a cohort of 57 adolescent scoliotic subjects has shown that both methods have similar performance on vertebral body position and axial rotation (null bias in both cases and standard deviation of signed differences of 1mm and 3.5° around, respectively). In average, the solution could be computed in less than 5min of operator time, even for severe scoliosis. The proposed method allows fast and accurate 3D reconstruction of the spine for wide clinical applications and represents a significant step towards full automatization of 3D reconstruction of the spine. Moreover, it is to the best of our knowledge the first method including also the cervical spine. These slides can be retrieved under electronic supplementary material.

Логіко-когнітивні моделі темпоральної дійсності під час прийняття оперативних рішень у кризових умовах функціонування техногенних систем (Ч. І)

Проведено аналіз та показано, що в когнітивній структурі особистості присутній іманентний темпоральний пласт, завдяки якому людина володіє здібністю конструктивно орієнтуватися у часовому просторі під час прийняття оперативних рішень в умовах загроз. Беручи це до уваги та враховуючи індивідуальність та неповторність кожної людини, такий феномен, за граничних режимів управління техногенними системами, може призвести до аварійних ситуацій з масштабними техногенними та екологічними наслідками. А отже, в разі невідповідного інтелектуального рівня і низької професійної підготовки оператор, у структурі управління енергоактивними об'єктами, не зможе своєчасно забезпечити реалізацію протиаварійних рішень. І тільки високий рівень інтелекту, відповідні психічні та вольові характеристики та професійна підготовка управлінського персоналу є запорукою ефективного протистояння загрозам виникнення аварійних ситуацій. Проаналізовано основні літературні джерела, глибиною до п'ятдесяти років, визначено проблему, мету і методи дослідження. Виклад основного матеріалу охоплює: аналіз проблеми прийняття рішень у кризових ситуаціях; опис інформаційного базису управління; ігрові моделі ситуацій управління; обґрунтування необхідності використання темпоральної логіки в процедурах прийняття рішень; аналіз сприйняття часу оператором та прийняття ним рішень з оцінкою швидкості мислення; логіко-когнітивну модель сприйняття часу оператором; логіко-лінгвіністичні темпоральні правила прийняття управлінських рішень в екстремальних ситуаціях.

Regularity of Solutions to Space–Time Fractional Wave Equations: A PDE Approach

Abstract We consider an evolution equation involving the fractional powers, of order s ∈ (0, 1), of a symmetric and uniformly elliptic second order operator and Caputo fractional time derivative of order γ ∈ (1, 2]. Since it has been shown useful for the design of numerical techniques for related problems, we also consider a quasi–stationary elliptic problem that comes from the realization of the spatial fractional diffusion as the Dirichlet-to-Neumann map for a nonuniformly elliptic problem posed on a semi–infinite cylinder. We provide existence and uniqueness results together with energy estimates for both problems. In addition, we derive regularity estimates both in time and space; the time–regularity results show that the usual assumptions made in the numerical analysis literature are problematic.

The development and evaluation of Robot Light Skin: A novel robot signalling system to improve communication in industrial human–robot collaboration

Abstract In a human–robot collaborative production system, the robot could make request for interaction or notify the human operator if an uncertainty arises. Conventional industrial tower lights were designed for generic machine signalling purposes which may not be the ultimate solution for robot signalling in a collaborative setting. In this type of system, human operators could be monitoring multiple robots while carrying out a manual task so it is important to minimise the diversion of their attention. This paper presents a novel robot signalling solution, the Robot Light Skin (RLS),which is an integrated signalling system that could be used on most articulated robots. Our experiment was conducted to validate this concept in terms of its effect on improving operator's reaction time, hit-rate, awareness and task performance. The results showed that participants reacted faster to the RLS as well as achieved higher hit-rate. An eye tracker was used in the experiment which shows a reduction in diversion away from the manual task when using the RLS. Future study should explore the effect of the RLS concept on large-scale systems and multi-robot systems.

Non-collision trajectories of service industrial robots

The innovative algorithm for robot collision testing was developed and debugged for programming industrial robots handling production and peripheral devices in a flexible manufacturing system. Due to this it allows the analysis of the robot effector and robot transition paths with the possibility of optimizing them in relation to the economy of the handling cycle, runway length, safety and operator time and overall handling performance. The key part of our proposal is to analyze the 3D model and its interpretation in a relevant form to enable data processing with modern computer graphics techniques with hardware support of calculations and work at the level of individual objects and polygons. Formalization of the robot's direct and inverse kinematic structure allows control of its interaction during servicing movements with other robot devices and peripherals. This ensures the optimal and unobtrusive trajectory of each mechanical element of the industrial robot serving the production and peripheral devices in the intelligent system.

Developments in continuous unattended monitoring systems

Continuous, unattended noise monitoring systems can immediately alert you should noise levels exceed defined criteria. Once alerted to an exceedance, operators can act to return levels to compliance. This approach has two significant limitations. First, the operator can only take action after the breach has occurred and therefore systems are only able to inform owners about problems that have occurred in the past, rather than allowing them to maintain compliance. Second, the noise limit exceedances might not be due to specific noise from the operator but from unrelated, residual noise in the often-complex noise climates around the particular site and will then be the cause for a false positive. Compliance breaches are frequently triggered by aircraft overflights, road traffic or community sources. Modern monitoring systems enable users to view noise characteristics and listen to the noise breach to determine the source and act if necessary. However, this approach can create a significant number of false positives each taking up operator time to address. A previous paper by the authors described how airport noise management systems have addressed this problem by combining data from other systems, and how different techniques are required in urban & industrial noise management. This paper describes developments in these techniques and gives examples of techniques that allow operators to take action before a compliance breach occurs, and to reduce the number of false positive alerts.

Early Outcomes of Routine Delayed Shunting in Carotid Endarterectomy for Asymptomatic Patients

The aim was to evaluate early outcomes of carotid endarterectomy (CEA) in asymptomatic patients using a standardised technique based on routine shunting after rapid plaque removal ("delayed"). A retrospective review of all asymptomatic patients who underwent CEA during a 10 year single centre experience (January 2007-December 2016) was performed. The technique was based on rapid endarterectomy with distal intimal edge visualisation, followed by routine shunt insertion; subsequent time spent on the manoeuvre and closure were completed under shunting. Primary endpoints were relevant neurological complication rate (RNCR) and death within 30 days. To better identify any difference related to changes in medical therapy, anaesthetic management, and different operators over time, patients were divided into group A (underwent CEA in the first 5 year period) and group B (underwent CEA during the second 5 year period). Univariate analysis of factors associated with RNCR was performed. Operator experience (seniority), expertise (CEA volume per year), and time period were incorporated. In total, 1745 patients matched the inclusion criteria and were enrolled. Altogether, 147 (8.9%) had contemporary contralateral stenosis ≥70% and 58 (3.5%) had contralateral internal carotid artery chronic occlusion. No patient died peri-operatively; major myocardial infarction occurred in 19 patients (1.1%). Overall, peri-operative RNCR was 0.6% (major stroke: n=6 [0.4%]; minor stroke: n=4 [0.2%]). RNCR distribution was maintained equally comparing group A and B (0.8% vs. 0.4%; p=0.17). No differences were found in RNCR when comparing operator experience (p=0.88) and expertise (p=0.93). Univariable analysis found diabetes as the only clinical factor influencing RNCR (odds ratio 3.79, 95% confidence interval 1.06-13.50; p=0.04); none of the other factors, such as time period, operator experience, and expertise, reached statistical significance. Routine delayed shunting associated with standardisation of the technique seems to be a safe and effective technique and contributes to maintaining the RNCR<1% over time and independently from operators and other clinical factors.

Rodents in the arena: a critical evaluation of methods measuring personality traits

The Open Field Test (OFT) and Mirror Image Stimulation (MIS) are used to measure behaviours related to an individual’s personality. These tests, carried out in a same novel arena, have been used for different taxa, but only a few papers underline the importance of method validation. Here we investigate how Eurasian red squirrels (Sciurus vulgaris) and Eastern grey squirrels (Sciurus carolinensis) behave during OFT and MIS. Next, we compare the performance between three analytical methods: the Principal Component Analysis (PCA), the Factor Analysis (FA) and an expert-based (EB) method. The EB approach classifies behaviours in groups relating on researchers’ knowledge and returns personality-trait values for each individual facilitating comparisons over studies and/or with new datasets. The comparison between the three methods gave similar results and high repeatabilities in some expert-based personality traits as well as PCA components and FA factors, showing that all three methods were valid to measure activity using OFT (both species) and sociability using MIS (grey squirrel). Repeatabilities of the other traits were less strong. Proportion of time spent in different behaviours did not differ with test duration, since shorter tests yielded valid measures of individual differences in personality. Shorter tests reduce operator time in the field, and are likely to reduce stress and arena-habituation of the animals. Test sequence affected the outcome of OFT: squirrels tested for the first time were more active than squirrels tested a second time. For the two squirrel species investigated, we recommend an OFT of 4 min and a MIS test of three and suggest to test an individual no more than 2 times per season with at least 2 months between repetitions.

Drugs of abuse extraction from whole blood using supported liquid extraction (SLE) and Extrahera automation prior to UPLC-MS/MS analysis

Whole blood continues to be a valuable tool in forensic toxicology for the immediate and near-term detection of illicit drugs and in cases where no other sample is available. Screening drugs of abuse can be complicated due to the wide variation of functional groups associated with different analyte classes. Most extraction techniques cannot extract all analytes using a single procedure without using non-optimal extraction protocols resulting in compromised extract cleanliness. Supported liquid extraction allows for the simultaneous analysis of cross functional analytes in a single extraction protocol without forfeiting extract cleanliness. The objective was to develop an automatable, common extraction procedure for multiple drug panels from whole blood matrix using supported liquid extraction (SLE) prior to UPLC-MS/MS analysis. The drug suites included amphetamines, benzodiazepines, cocaine, opiates, ketamine, buprenorphine, Z-drugs and THC-COOH. Blank whole blood was spiked with drugs from various panels at 13 ng/mL for the analytes and appropriate deuterated internal standards. Whole blood extraction was performed using ISOLUTE SLE+ 1 mL capacity columns evaluating pH control and optimum extraction solvent combinations. The resultant extracts were evaporated to dryness and reconstituted in mobile phase for subsequent UPLC-MS/MS analysis. Samples were analyzed using a Waters ACQUITY UPLC coupled to a Quattro Premier XE triple quadrupole mass spectrometer (Waters). Positive ions were acquired using electrospray ionisation in the MRM mode. Initial investigations focused on sample treatment. Extraction conditions were evaluated using spiked whole blood pre-treated 1:1 (v/v) with various ammonium hydroxide (aq) concentrations from 0.1 % up to 2 %. 0.1 % NH 4 OH (aq) was selected as the pre-treatment as many of the drugs are basic in nature, however an environment at this pH value also allowed concomitant extraction of THC-COOH. Loading 1 mL of pre-treated whole blood led to the extraction of matrix components in the form of red blood cells. Evaluation of various loading volumes from 500 to 900 μL resulted in selection of 750 μL (1:1, v:v) as the optimal loading volume for extract cleanliness. Dichoromethane, dichloromethane/isopropanol acid and methyl tert-butyl ether combinations with various modifiers were evaluated for extraction efficiency. Benzoylecgonine could only be extracted efficiently when using dichloromethane as the extraction solvent. The optimum extraction protocol provided recoveries greater than 70 % for nearly all drugs spiked into whole blood. Benzoylecgonine and buprenorphine recovered 47 % and 52 % respectively. RSD values for all drugs were under 10 %. Lower recoveries for benzoylecgonine and buprenorphine did not prevent quantitation at sub-ng/mL concentrations. Evaporative effects were eliminated using 0.05 M HCl in methanol prior to evaporation. Calibration curves constructed from 1–500 ng/mL demonstrated excellent linearity and r 2 > 0.99 for all analytes. LLOQs were determined to be sub-ng/mL for each analyte when extracting 375 μL of whole blood, with the exception of THC-COOH (5 ng/mL). MRM analysis for common phospholipid molecules demonstrated the optimum method yields extremely clean extracts. This method was transferred to the Extrahera sample automation platform for repeat investigations into recovery, reproducibility and linearity and in nearly all analytes, the automation approach improves upon the manual approach for acquired data while also saving operator time. This poster describes the suitability of ISOLUTE SLE+ for the rapid and reliable extraction of multiple analyte panels from whole blood in a single, fully-automatable assay on the Extrahera platform, prior to UPLC-MS/MS analysis.

An Automatic Evaluation Platform for Feature Matching Algorithms Based on an Orbital Optical Pushbroom Stereo Imaging System

Thanks to the high robustness of feature-based matching algorithms, they can be applied in remote sensing (RS) applications with complex image changes. However, evaluating feature matching algorithms on RS images is still challenging, because creating ground truth matching data sets of RS images costs a lot of both computing time and human operator time. Therefore, in this letter, we present an evaluation platform for simulating RS ground truth data sets of feature-points correspondences based on a customizable orbital optical pushbroom stereo imaging system. With the help of the proposed platform, evaluating feature matching algorithms could be fully automatic and customized. The performance of three state-of-the-art feature matching algorithms based on local transformation constraint is evaluated and discussed on the proposed platform with comprehensive experiments. The evaluation results of the platform are also compared with the manual evaluation results of 10 pairs of real RS stereo images. The evaluation results show that the proposed platform indeed offers an efficient way for evaluating RS feature matching algorithms.

A Blended Continuation Method for Solving Steady Inviscid Flow

Steady flow field solving is wieldly used in aircraft aerodynamic design, efficiency of steady flow field solving has great influnence on efficiency of aircraft aerodynamic design. A continuation method that blended Laplacian operator and pseudo time marching method for solving steady inviscid flow problem is proposed. In steady flow problem, the field is usually initialized as an uniform field before starting iteration. This resulted in the fact that the initial residual in only nonzero on wall boundary. Based on this feature, Laplacian operator is introduced to accelarate convergence at the starting stage of nonlinear solving. At the ending stage of nonlinear solving, the blended continuation term is biased to pseduo time marching method to avoid over dissipation graduately. To establish a complete continuation method, the starting, evolution and termination method are also described. At last, the proposed continuation method is implemented in a finite element solver, and tested aginst GAMM channel and NACA0012 foil subsonic and transonic cases. Numerical test results confirmed that the blended continuation method could get an efficency improvement about 1/3 to 1/4 comparing with stand alone Laplacian continuation and much more better than pure pseudo time marching method.

Advances in Technology and Its Application: Radiotherapy Treatment Planning.

Treatment planning for radiotherapy has become unthinkable without computer algorithms for dose optimization. Although the need for optimization algorithms originated from the complexity of treatment delivery technology such as intensity-modulated radiotherapy, volumetric-modulated arc therapy, and robotic stereotactic radiotherapy, the focus has shifted to refining goals and methods of optimization itself. Dose optimization chiefly advances in 3 directions: human interface and automation, compensation of changing patient geometries, and diversification/individualization of radiation dose prescription. Traditionally, dose optimization requires the definition of numerical treatment goals, followed by an interactive trial-and-error process to adjust the correct, patient-specific balance of these goals. Being both operator dependent and time consuming, methods are needed that produce high-quality treatments efficiently, with the long-term objective of autonomous dose optimization. Expedient treatment planning is also key to treatment adaptation to changes in patient geometry. Despite all efforts to image and adapt at treatment time, some residual uncertainties remain and must be compensated via treatment planning. Reformulations of the dose optimization problem are joined with various image-based 4D patient models to ensure treatment robustness against geometric uncertainties. Robust optimization leads to a deviation from customary dose prescription in favour of more predictable dose delivery. The dose distribution can be individualized further by additional functional image information, aiming to guide the dose towards undertreated volumes and away from overtreated ones, also known as dose-painting. Multimodal imaging is increasingly integrated into treatment planning, making it a natural consequence to supplant computed tomography by magnetic resonance imaging to establish MR-based radiotherapy.

Classification of Task Type and Reaction Time of Operator in Simulated Multiple Robot Tele-Exploration

Classification of Task Type and Reaction Time of Operator in Simulated Multiple Robot Tele-Exploration

Design of working procedure for handling the breakdown machine in parameter of reaction time based on Jidoka system approach in cement company

Packaging is not a complementary of the product. Packaging is an interface between producer and consumer in a supply chain. Portland cement is one of the products which is usually distributed in unit packed with bags made of kraft paper. Cement production that done with large capacity machines requires the amount of bag in quantity that much anyway. The production of bag factory in Cement company line 4 ideally could reach 9-10 million bags per month. In fact, the average production of cement bag from January to June 2012 is 6.5 million bags per month. In addition, the average defects of work in process in the range of the same month reached 56,000 tubes per month. This indicates that engine breakdown is happen frequently and there is a lack of good performance in term of production process quality control. Long reaction time of operator against the possible breakdown and the breakdown that occur is the cause of the length of time handling problems on the machine, so much going on a lot of waste in time and there are work in process defects that pass to the next process. Minimizing the reaction time to the breakdown of machine can be done with the implementation of jidoka system on the production floor. Andon which is the tool of jidoka will ensure operator and other parties (operators, technicians, foreman) gather to repair the machine effectively and also efficient in term of time. The lights that flashing and the sound of alarm that raised by andon will ensure this happen. Working procedures with the jidoka system approach is proven can minimize the reaction time to the breakdown of machine. Based on calculations, minimizing of time can reach up to 93.66%. The mathematical model for the jidoka system approach that has been valid then converted to a standard operating procedure in handling the breakdown of machine in bag factory. The standard operating procedure that proposed will be technically efficient and effective in terms of time and method to handle the breakdown of machine.

Comparison of color flow with standard ultrasound for the detection of endotracheal intubation

IntroductionIntubation is a frequently performed procedure in emergency medicine that is associated with significant morbidity and mortality when unrecognized esophageal intubation occurs. However, it may be difficult to visualize the endotracheal tube (ETT) in some patients. This study assessed whether the addition of color Doppler was able to improve the ability to visualize the ETT location. MethodsThis study was performed in a cadaver lab using three different cadavers chosen to represent varying neck circumference. Cadavers were randomized to tracheal or esophageal intubation. Blinded sonographers then assessed the location of the ETT using either grayscale or color Doppler imaging. Accuracy of sonographer identification of ETT location, time to identification, and operator confidence were assessed. ResultsOne hundred and fifty intubations were performed and each was assessed by both standard and color Doppler techniques. There were 78 tracheal intubations and 72 esophageal intubations. The standard technique was 99.3% (95% CI 96.3 to 99.9%) accurate. The color flow technique was also 99.3% (95% CI 96.3 to 99.9%) accurate. The mean operator time to identification was 3.24s (95% CI 2.97 to 3.51s) in the standard approach and 5.75s (95% CI 5.16 to 6.33s) in the color flow technique. The mean operator confidence was 4.99/5.00 (95% CI 4.98 to 5.00) in the standard approach and 4.94/5.00 (95% CI 4.90 to 4.98) in the color flow technique. ConclusionWhen added to standard ultrasound imaging, color flow did not improve accuracy or operator confidence for identifying ETT location and resulted in a longer examination time.

From shallow horizontal drilling to ERD wells: How scale affects drillability and the management of drilling incidents

The context of drilling operations is quite variable in geometric scale and complexity. Wells range from Extended Reach Drilling (ERD) wells with measured depths greater than 10 km to exceptionally shallow wells no longer than 2 km but only 200–300 m in true vertical depth. With the objective of achieving greater levels of drilling automation, it is important to understand how the well geometrical scale impacts drillability and the management of drilling incidents.The robust control of the drilling process necessitates the correct management of delays in the system. Some sources of delay are directly linked to physical dimensions, while others are the results of the system infrastructure. Time delays due to the travel of information through a medium belong to the first category while delays due to signal filtering or processing and actuator latency belong to the second category. The transient response of the drilling system greatly influences the controllability of the drilling process and both the detection and reaction times for drilling incidents such as over-pulls or pack-offs.This paper proposes a categorization of the various sources of delay in a drilling system. A brief review of similar sources of delay in other industries is presented first, and then the sources of delay are characterized into four classes: the elasticity, inertia, and friction of the physical system, measurement refresh rate and latency, processing latency, and maximum actuator acceleration. Delays within these four classes are quantified for three different scenarios: a 10 km-long ERD well, a shallow horizontal well, and a three-dimensional shale well. Illustrative examples of the four classes of delay are presented within these scenarios. Any drilling automation system faces a varying set of constraints for each application, which should influence both the automation procedures themselves as well as sensing requirements.The paper illustrates how scale influences the necessary constraints in drilling procedures, by comparing the delay within the full range of drilling scenarios. Human operator and rig system reaction time and variable awareness to drilling dysfunctions are the most limiting factors in improving drilling efficiency. The automation of drilling procedures with robustness considerations for scale and latency issues therefore plays an important role in increasing drilling performance.

Evaluation of accuracy and precision of a smartphone based automated parasite egg counting system in comparison to the McMaster and Mini-FLOTAC methods

Fecal egg counts are emphasized for guiding equine helminth parasite control regimens due to the rise of anthelmintic resistance. This, however, poses further challenges, since egg counting results are prone to issues such as operator dependency, method variability, equipment requirements, and time commitment. The use of image analysis software for performing fecal egg counts is promoted in recent studies to reduce the operator dependency associated with manual counts. In an attempt to remove operator dependency associated with current methods, we developed a diagnostic system that utilizes a smartphone and employs image analysis to generate automated egg counts. The aims of this study were (1) to determine precision of the first smartphone prototype, the modified McMaster and ImageJ; (2) to determine precision, accuracy, sensitivity, and specificity of the second smartphone prototype, the modified McMaster, and Mini-FLOTAC techniques. Repeated counts on fecal samples naturally infected with equine strongyle eggs were performed using each technique to evaluate precision. Triplicate counts on 36 egg count negative samples and 36 samples spiked with strongyle eggs at 5, 50, 500, and 1000 eggs per gram were performed using a second smartphone system prototype, Mini-FLOTAC, and McMaster to determine technique accuracy. Precision across the techniques was evaluated using the coefficient of variation. In regards to the first aim of the study, the McMaster technique performed with significantly less variance than the first smartphone prototype and ImageJ (p<0.0001). The smartphone and ImageJ performed with equal variance. In regards to the second aim of the study, the second smartphone system prototype had significantly better precision than the McMaster (p<0.0001) and Mini-FLOTAC (p<0.0001) methods, and the Mini-FLOTAC was significantly more precise than the McMaster (p=0.0228). Mean accuracies for the Mini-FLOTAC, McMaster, and smartphone system were 64.51%, 21.67%, and 32.53%, respectively. The Mini-FLOTAC was significantly more accurate than the McMaster (p<0.0001) and the smartphone system (p<0.0001), while the smartphone and McMaster counts did not have statistically different accuracies. Overall, the smartphone system compared favorably to manual methods with regards to precision, and reasonably with regards to accuracy. With further refinement, this system could become useful in veterinary practice.

Claiming a place for Guinea Bissau on the hottest shelf margin on planet Earth

The recent glut of giant oil and gas hydrocarbon discoveries on the North West African coast (Figure 1) began in 2014 with the SNE-1 discovery by Cairn in Senegal. This play-making well targeted Albian sandstones and Aptian carbonates in a structural trap, at the eroded edge of the Early Cretaceous platform margin. There are a number of interesting play elements at work in this play that require definition so that a model can be extracted and reused elsewhere along the margin in the chase for analogue traps. Where we will end up is Guinea Bissau, Senegal’s southern neighbour, where the plays is as yet unexplored yet appears to have an even more promising potential, but first – SNE. The SNE discovery has been presented to the industry by operator and partners several times over the last few years, including a presentation at the recent HGS PESGB African conference by Wytze de Boer et al. of Cairn Energy (Geophysics of the SNE Field, Senegal, HGS PESGB 16th African Conference, 2017). It is hardly surprising that industry is interested in this discovery as, with current resource estimates exceeding 500mmbbls, this was the biggest discovery in the world in 2014 and a truly ground-breaking, basin opening innovation. Most remarkable was that the discovery was oil – bucking the global trend of discoveries that was otherwise suggesting we have fine tools to explore for big gas resources but struggle to find big oil. The Liza-1 (>2bn bbls oil) discovery in Guyana in 2016 put this concept firmly to bed, yet the SNE discovery is still one of the few giant oil resource additions drilled this century.