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We derive a new earthquake focal mechanism catalog for 86 Mw>4.0 earthquakes that occurred in the Myanmar region from 2016 to 2021. We apply the generalized Cut-and-Paste inversion method to a new set of regional broadband waveform data to obtain the earthquake focal mechanism and centroid depth with uncertainties estimated in a bootstrapping manner. Compared with global earthquake catalogs, our results are better aligned with mapped, active faults and reveal seismic activity along unmapped, blind faults. Our new catalog shows that the Sagaing Fault is more active in its northern segment with deeper seismogenic zone (∼27 km) compared to its southern segment that has a shallower seismogenic zone (∼10 km), sandwiching a seismic gap in its central segment. Earthquakes that occurred on the unmapped, blind faults beneath the Central Myanmar Basin at shallow depths (3–12 km) suggest a dominating northeast–southwest compressional stress field. Shallow earthquakes beneath the Indo-Myanmar Range (IMR) are rare, instead, north–south-oriented strike-slip faults are active within the deep accretionary wedge or lower crust of the Myanmar plate between depths of 20 and 40 km. At the eastern edge of the IMR, earthquakes with high-angle thrust mechanisms occurred between depths of 30 and 48 km, likely along steep faults separating the accretionary wedge from the Myanmar forearc crust. High-resolution intraslab focal mechanisms show that to the north of 22° N, slab deformation is dominated by strike-slip earthquakes with subvertical fault planes down to a depth of ∼25 km beneath the slab, suggesting lateral shear within the slab due to the northward motion of the Indian plate. To the south, more normal-faulting earthquakes suggest a stronger role of plate-bending processes in the slab deformation.

Myanmar occupies a complex region in the active Indo-Burma subduction system. To illuminate the upper 10 km crustal structure of central Myanmar and obtain new insight into the subduction system, we jointly use P-wave polarizations and receiver functions (RFs) to construct a high-resolution VS profile based on a Bayesian Markov chain Monte Carlo approach. This obtained profile clearly delineates six tectonic units and their boundaries, including the Indo-Burman ranges (IBR), the IBR-fore-arc basin boundary, the fore-arc basin, the volcanic arc, the back-arc basin, and the Sunda plate. The Sunda plate has relatively higher upper crustal VS ( >3.0 km/s) and thinner sedimentary cover ( ∼1 km) compared with the Central Myanmar basin in the Burma plate. The fore-arc basin, containing thick sediments ( >10 km), and the back-arc basin, with thinner sediments ( ∼1-6 km), are separated by a region with higher VS ( ∼3.0 km/s), which represents crystallized magma beneath the volcanic arc. A narrow zone of relatively high-VS ( ∼2.6-2.7 km/s) ophiolites is situated between the fore-arc basin and the IBR. We also find a narrow zone of high-VS ( ∼2.9 km/s) metamorphic rocks contained within the low-VS (≳2.3 km/s) IBR. This study suggests that the proposing joint inversion of two types of single-station measurements, that is, P-wave polarizations and RFs, can robustly and computationally efficiently image the shallow VS structure and provide a reliable uncertainty estimation. Ministry of Education (MOE) National Research Foundation (NRF) This research was supported by the National Research Foundation of Singapore and the Singapore Ministry of Education under the Research Centers of Excellence initiative, via the Earth Observatory of Singapore (EOS) Grant Numbers 04MNS001953A620 and 04MNS001913A620. J. Yao and P. Tong were also partly supported by the Ministry of Education Singapore Academic Research Funding Tier 2 Grant MOE2019-T2-2-112 and MOE2018-T2-1-059.

A 58 year old man was brought to hospital in state of deep coma following severe headache for one day. His GCS was 3/15 and had flaccid all 4 limbs with equivocal planter response on both sides on arrival. NECT head showed acute subdural haemorrhage with surrounding cerebral oedema, mid-line shift and corning of brain stem. After giving mannitol and dexamethasone, four hours later, he became fully conscious and orientated; his motor power returned to normal. He was on warfarin 3mg daily for rheumatic mitral valvular heart disease with atrial fibrillation and his INR on arrival was 3.5. He had intractable hiccups once he regained consciousness. Both pharmacological and non-pharmacological measures were tried for distressing hiccups; there was no therapeutic success. His hiccups disappeared completely only after removing the haematoma by burr hole surgery.

A young man presented with abdominal pain and vomiting after eating Naphthalene Mothball. He had dyspnea, central cyanosis (SaO2 on air was 67% on air), marked pallor, deep jaundice and dehydration. His urine color was black; and, his plasma in clotted blood sample was brownish. He was treated as methemoglobinemia due to suicidal Naphthalene Mothball poisoning with fluid and electrolyte replacement, ascorbic acid, N-acetylcystine and exchange transfusion twice with four units of whole blood. Dramatic improvement in central cyanosis immediately following exchange transfusion. Psychiatric consultation and counselling were done; he admitted the main reason for committing suicide was socioeconomic stress due to COVID-19.

To maximize the hydrocarbon production from wells with sand, the new operating philosophy adopted for sand control. It focusses on limiting production based on the acceptable erosion risk instead of sand production rate. To achieve this, combination of sand production data and laboratory analysis on particle size of the produced sand is crucial. This paper aims to present the challenges and solutions applied for gas terminal sand data acquisition and lab analysis to obtain representative sand data. A discussion on typical sand acquisition technologies is discussed. The experience from sub-optimal performance within the company are analyzed, the improvement opportunities are identified. Due to the volatile nature of condensate as compared to crude oil, alternative to conventional sampling method need to be applied for gas terminals. Dual particle filtration setup was developed to capture the wider particle range down to 1 micron. The data acquisition was conducted using a closed loop sand sampling system where the outlet of the sampling equipment is connected back to the processing system. To cover the dynamic of sand production, the data acquisition conducted at both normal and pigging operation for 6 hours continuous duration. The collected samples were analyzed using Automated Minerology imaging technology for particle sand distribution and minerology determination The facility was not designed to receive sand including sand sampling facilities, hence imposed several challenges to acquire the sand data. From the experience during the sampling activity, there are few good observations and lessons learnt from utilizing the innovative approach as follows. The online continuous sampling allows longer sampling duration without causing interruption to operation. The dual particle filtration ensures as much as possible solid particles that pass through the system will be filtered for analysis. The close loop sampling setup minimizes the exposure of harmful hydrocarbon to the personnel with might contain hazardous contaminant. Sampling that is conducted at different operation mode i.e., normal and pigging will provide wider range of sand PSD and volume. Due to fines sand, only a small volume of sample was captured at the filter and insufficient for the analysis using conventional LPSA/Dry Sieve method. The recent technology approach via Automated Minerology imaging technology eliminates the issue of limited sample volume. The experience from the sand data acquisition activity enhances understanding and provides opportunities to explore other sampling technologies/techniques and analysis methods. It is important for the team to assess in totality.

Snakebite is an important problem in Myanmar. Regionally, bites by Eastern Russell's vipers, Daboia siamensis (Viperidae, Viperinae), and monocled cobras, Naja kaouthia are considered medically important, but those categorised as “green snake” bites are not. However, these may include bites by green pit vipers, Trimeresurus spp. (Viperidae, Crotalinae) for which no antivenom is available in Myanmar. Elsewhere in Southeast Asia, these snakes are reported to cause local and systemic envenoming. As part of the Myanmar Snakebite Project, prospective case data were collected over 3 years from five hospitals in the Mandalay region. These included 3803 snakebite cases reported from Mandalay region. Of these, 355 were listed as bites by a witnessed green-coloured snake. In 22 cases, the snakes responsible were retained and preserved, then expertly identified; 21 were medically important white-lipped pit vipers (Trimeresurus albolabris), and one as an Asian vine snake, Ahaetulla prasina (Colubridae, Ahaetuliinae) which is not of medical importance. Among confirmed Trimeresurus albolabris bites, 15/21 developed swelling of the bitten limb, and 3/21 coagulopathy, defined as a positive 20-min whole blood clotting test (20WBCT). None developed necrosis, blistering, thrombocytopenia or acute kidney injury (AKI). Of the remaining 333 patients bitten by green snakes that were not specifically identified, 241 (72%) developed swelling of the bitten limb, and 62 (19%) coagulopathy. AKI occurred in 21/333 patients, but only one required dialysis. At least 10/21 of the cases with AKI in this study were more likely to represent bites from Trimeresurus spp. than D. siamensis because the snake responsible was brought into the hospital, examined and described by the treating physician as “green-coloured”. This study describes a previously unpublished case of AKI from envenoming by T. erythrurus in Yangon, and reviews cases of AKI following bites by this species and T. albolabris in Myanmar. This confirms that, at least on rare occasions, Trimeresurus spp. envenoming can cause AKI. This has important implications for snakebite management in Myanmar as the finding of local swelling, coagulopathy and AKI is generally considered pathognomonic of D. siamensis envenoming. Further collection of confirmed Trimeresurus spp. bites is required in Myanmar in order better to define the syndrome of envenoming and to assess the possible need for antivenom against Trimeresurus spp. in this country.

Background: In COVID-19 pandemic, the diagnosis and treatment must be as early as possible to save the life of each patient. Moreover, screening of asymptomatic carriers, close contacts or healthy subjects must not be delay to prevent transmission to publics. For confirmation of diagnosis of SARS-CoV-2 infection, nasopharyngeal swab must be tested either by real-time Reverse Transcription Polymerase Chain Reaction (RT-PCR) tests or Rapid Antigen Test (RAT). RAT is faster, easier and cheaper; thus, it is suitable for health service in developing country. Objectives: The aim of this study was to assess the diagnostic accuracy of Roche SARS-CoV-2 Rapid Antigen Test (RAT) in diagnosing SARS-CoV-2 infection. Methods: Hospital based exploratory study was done in out-patient department and fever clinic, and molecular laboratory of No. (1) Defence Services General Hospital. Nasopharyngeal swabs were taken, and the Roche SARS- CoV-2 RAT was conducted in parallel with RT-PCR test (reference standard). Results: Among the 932 patients/subjects recruited, RT-PCR was positive in 468 individuals, corresponding to a prevalence of 50.2%. The RAT was positive in 363 patients (60.4%), false positive in 120 patients; it was negative in 569 individuals (39.6%), false negative in 225 patients. The overall sensitivity of the RAT was 51.9% (95% Confidence Interval [CI] 47.29-56.53) and, the specificity was 74.1% (95% CI 69.9-78.07); positive predictive value was 66.9% and negative predictive value was 60.5%. The sensitivity varied with Ct value; 78% in clinical samples with Ct values < 20, 57.5% in those with Ct values between 21 and 25, 41.8% in samples with Ct values between 26 and 30, and, 36.4% in samples with Ct value > 30. Conclusion: The accuracy of the SARS-CoV-2 Roche RAT in diagnosing SARS-CoV-2 infections was inferior to RT-PCR and manufacturer’s data. The sensitivity was with low Cycle threshold values < 20 which were inversely related to the viral load. RAT test should be used in association with clinical impression of physicians. In hospital setting especially in emergency department, the role of RAT should be reconsidered in those patients presenting with anosmia and some cases of dyspnoea, late symptoms in the course of disease, as the RAT results would be false negative. Other errors may arise if the operator for RAT has to handle more than recommended tests per hour especially in the peak of epidemics.

In oilfield with significant gas production, either from high associated gas production or non-associated gas (NAG) wells, gas injection is often prioritized due to the aim of oil production sustainability compared to gas export, with only the remaining gas flow not taken by the injection wells is exported as sales gas. However, with gas emerging as a cleaner energy source as compared to oil and instability in oil price, higher gas demand is expected in the future. Due to this, flexibility in managing the allocation between gas injection and gas export would be an advantage, especially with the cyclical demand peak due to winter and summer seasons. A case study for optimization for a unified management and automation of the gas export and gas injection is presented in this paper, which includes the flexibility in prioritizing either utilization options and managing the impact of changes in injection gas supply accordingly via process control and automation. With the adoption of new controllers, operator would now be able to choose which priority mode would be given considering subsurface injection and gas export requirements. For example, when priority is given to the gas injection as per current operating mode, only the remaining gas balance will be used for export. However, when gas export is prioritized, operator would have the option to set the minimum gas export flow that is required, and the control system will automatically control the allocation for sales and injection, including automatically calculating and assigning the injection gas flow to each injector wells when the resulting gas injection supply is changed as a result of gas export prioritization. With the automation exercise, the operator would not need to conduct the manual adjustment of choke valves opening to regulate the gas injection and gas export flow, rather only the usage mode prioritization and the desired flow setpoints for both cases are required. The scheme allows the operator to take advantage on the opportunity of prioritizing gas export or injection depending on prevailing market demand and operational requirement needs for maximizing the value from the field.

From upstream production process/operation perspectives, adoption of digital twin linked with real-time data for operational monitoring and advisory can assist in early determination of abnormalities that can result in potential failure events, based on deviation from the operating setpoints and limits. In addition, prediction capability of the digital twin model can assist in prevention of unplanned production deferment and proper maintenance planning. The digital twin model can also recommend optimum operating points based on changes in the system as operational guidance to further improve and optimize the system performance. This paper outlines the holistic approach taken for the development of digital twin-based advisory system for upstream process monitoring and optimization. Based on a case study, a step-by-step approach for the development of a digital twin model for fuel gas system is being described. This technology combines various aspect of process and operation models. The Integrated Operating Limit Model acts as the first layer of digital twin model, which provides the operators with a quick assessment based on the visualization or representation of the real time operating points versus the operating set points and limits defined in the system. Process simulation model predicts other operating parameters not covered by the existing instrumentations, serving as virtual analysers, providing near real-time equipment and unit performance. Data driven model can be used for prediction, optimization and anomaly detection, and based on the prediction model development, comparison between linear regression (LR) versus decision forest-based model showed LR to be more reliable approach based on the validation against the actual operation data especially during upset condition (R2 of 0.9 vs 0.27). A graphical user interface was also developed to translate and summarize the model outputs into a clear visualization to be used by the operation team as advisory and surveillance tool. Combination of these models’ outputs would allow operator to essentially screen for potential process upset and apply further optimization based on the recommendation provided.

Sand control application in gas wells is very challenging, especially in the application of a standalone sand screen (SAS) due to the high erosional risks. Many failures have been observed in the industry over the years causing production deferments and additional OPEX to the operators for remedial sand control operations. This work presents the performance evaluation of a unique SAS in open hole completion concept piloted in a horizontal gas well and the replication in other new wells in a Malaysian gas field. In 2012, a pilot gas well was completed with SAS with optimally placed flow segmentizers along the horizontal completion to limit the screen erosional risks. The placement was determined using a tool developed through an R&D. It estimates the optimum locations of the flow segmentizers based on the targeted SAS life or erosional velocity limit imposed. At the heart of it is a proprietary erosion model specifically developed for SAS application. The well performance was compared to adjacent wells producing from the same reservoir but completed using the conventional open-hole gravel pack. The pilot well achieved higher Productivity Index in comparison to the adjacent wells. Over the 10-year observation period, the production performance was consistent with minimal skin values and no sand production issues. Multifinger Imaging Tool (MIT) was run to measure the erosion levels in the tubing and the result indicated very minimal erosion because of sand production even after several years of production. Recently, another one (1) new infill well was drilled and completed with the same concept as the pilot well. The segmentizer placements were supported by an optimization study based on the expected production scenario. Positive flow back results with no indication of sand production was detected from the intrusive sand monitoring equipment. With the application of SAS and flow segmentizers, a cost reduction of 25% as compared to more complex application of open-hole gravel pack was realized.

In this paper, a strategy of deploying a novel compact electric generator (n-CEG) is investigated for generation of electrical energy replacing conventional mini turbine generator (MTG) technology. Deployment of these technologies are driven by growing power requirement at offshore facilities with aging conventional equipment currently installed at these facilities. With advancement and potential benefit that the technologies can offer, a high-level feasibility study is needed to ensure suitable technology is deployed. This paper seeks to cover the feasibility of n-CEG technology deployment at offshore facility as compared to MTG and floating solar panel inclusive of technical and cost perspective.

Flaring of associated gas at hydrocarbon production facilities contributes to Scope 1 of GHG emissions and is a wastage of a valuable energy resource. A wide range of technical and technological solutions have been proposed to address this issue. However, the volumes of flared associated gas are rarely large enough to capture and monetize economically at a single location hence the struggle to achieve ZRF, especially at offshore locations. This paper presents the practical solutions to monetize this small-volume associated gas and the resulting techno-economic assessments of these options at five different offshore locations. A thorough state-of-the-art review has been conducted categorizing external outlooks on process improvement initiatives and/or technologies that can be applied for flaring and venting management. The study focuses on solutions for offshore facilities where the volume of associated gas is small, within the range of 5MMSCFD or less. Five fields in offshore Malaysia were considered for this purpose. A two-steps techno-economic assessment with a case study field was carried out to firm up IRR, NPV, CAPEX, OPEX, variable cost and revenue for each technology solutions. The four leading solutions were: 1. recovering the flare gas and utilizing it as fuel gas to generate electric power using small-scale generators, 2. recovering the flare gas and utilizing it for gas reinjection through existing idle reinjection facilities, 3. installing in-situ small-scale gas-to-liquids conversion process, and 4. improving the efficiency of the existing processing system using data analytics to further reduce or eliminate the gas volumes. Except for the fourth option, additional equipment are required with their respective footprints. The existing processing system and platform size played a major role in determining the right solution for a given location. For the identified offshore field case studies, the vent gas reduction is achieved through Solution 1 at two fields, Solution 2 at one field, and Solution 3 at two fields. The techno-economics assessment shows that power generation (Solution 1) requires the lowest CAPEX and provides the highest IRR 21% with an NPV of USD4.2 million. The gas reinjection (Solution 2) also has lower CAPEX but the production increment is not significant and hence lowest IRR. In conclusion, there is no single standard or generic solution to help recover associated flare and vent gases and monetize it. Operators need to consider several factors especially on flare or vent volume variation, low pressure, and limited space at brownfield facilities.