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The Growler field produces oil from the middle Birkhead formation. The main production area is a low relief four-way dip closure consisting of channel reservoir with thickness of ~15-20m that has been mapped from the 3D seismic amplitudes and confirmed by wells. Interpretation of the thin and lower quality oil reservoirs in the form of secondary channel and floodplain sandstone deposits from the seismic has not been successful. The inability to discriminate and delineate the geological and/or fluid facies is the main challenge to further explore and develop the field. The challenge is worsened by the uncertainty in the well logs and the poor-quality nature of land seismic data. An advanced pre-stack geostatistical inversion study has been carried out aiming to solve the observed key issues: i) discrimination of different reservoir facies from elastic properties derived from 3D seismic amplitudes; ii) enhancement of the quality of the seismic to resolve the inherent uncertainty associated with the AVO responses; iii) mitigation of the ambiguity of false AVO anomaly due to carbonaceous shale that had led to unsuccessful drilled well. The applied geostatistical inversion study workflow includes iterative seismic petrophysics and rock physics modeling to produce a good quality and consistent set of well logs; robust seismic data conditioning for removal of coherent and incoherent noises, and alignment of seismic events, with the resultant seismic AVO response calibrated with well data; deterministic inversion of conditioned multiple angle stacks and litho-facies estimation using Bayesian inference to provide understanding on the intricacies of the aforesaid challenges before application of geostatistical inversion. Joint facies and elastic properties inversion facilitated by Bayesian-based geostatistical inversion using Multigrid Markov Chain Monte Carlo algorithm has resulted in highly detailed subsurface facies models that show excellent match at most of the 14 blind wells not used in the study., Open-Access Online Publication: May 29, 2023

Beach Energy has successfully discovered and produced hydrocarbons from the Western Flank of the Cooper Basin since 2002. Beach Energy's entire acreage is covered by good quality Pre-Stack Time Migrated Seismic Data (Pre STM). Multiple drilling campaigns executed over the years have confirmed that structure and migration are the most significant risks to finding additional hydrocarbons in the area. Since an assessment of the pre-drill gross rock volume (GRV) is crucial to inform future exploration campaigns, extensive efforts were made to fully understand the GRV distribution using a stochastic approach and the risks associated with the presence of four-way closures. Once the depth conversion project is completed, exploit the value of the latest stochastic technology and the benefits of a PreStack Depth Migration (PreSDM) reprocessing. The risks (probability of a structure being present), uncertainties (GRV distribution) and reservoir depth estimation were validated by the post-drilling results of 13 exploration and appraisal wells. Drilling results confirmed that the chosen approach is more precise and accurate than previous attempts to quantify risks and uncertainties using the same input data., Open-Access Online Publication: May 22, 2023

Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines. This report is the 10th of a suite of STECF EWG reports dedicated to the evaluation of the implementation of the Western Mediterranean Sea Multi-Annual management Plan (hereafter, MAP), following EWG reports 18-09, 18-13, 19-01, 19-14, 20-13, 21-01, 21- 13, 22-01 and 22-11. The group was requested to continue the development of socio-economic indicators to be used in the evaluation of management measures for the West Med MAP in both West Med management units (EMU1 and EMU 1) (TOR1). Two roadmaps were discussed, a short term approach and a long term approach which would consider the expansion of all the mixed-fisheries bio-economic models to both management units. As a first step, the group focused on the proposal of harmonizing the economic indicators across the models implemented (TOR2). The group was than requested to further develop the approach implemented during EWG 22-01 to identify persistence hotspots of the six target species of the West Med MAP using scientific survey data (MEDITS) in combination to commercial spatial data (VMS joined with logbooks), to test existing and additional closure areas (TOR 3). The group was also requested to revise Article 8 of the 2023 fishing opportunities for the West Med MAP (COUNCIL REGULATION (EU) 2023/195), which lists the compensation mechanisms that MSs can implement within the West Med MAP to obtain additional fishing days in 2023 (TOR 4). For TOR 1 a roadmap was discussed and proposed on how to organise the work on socio-economic assessments for the West Med MAP in 2023. The EWG suggests that here should be a three-step process: a scoping exercise (done with EWG 23- 01), a meeting with stakeholders in the middle of the year to discuss their perception of the socio-economic consequences of measures of the West Med MAP and the running of scenarios during EWG 23-11 with results from socio-economic assessments. The EWG notes that the modellers have only the five-day meeting in September to run scenarios. Therefore, it would be crucial for the success of the assessments that the 6 scenarios provided by DG Mare for the EWG 22-11 and with some adjustments for EWG 23-01 will not change for EWG 23-11. It is crucial because those scenarios are already implemented in the models and the implementation of new scenarios would take a lot of time. The EWG proposes to run a few additional scenarios with only one measures to separate impacts of certain measures from the six scenarios where a mixture of measures is included. This would hopefully allow to give an indication what additional efforts may be necessary to reach MSY (in 2025 but also beyond in case the objective is not reached by 2025) and when gains from the implementation of the West Med Plan could be expected. The EWG observes that modelers need to put in additional effort and resources to improve the models for an improved assessment of the West Med MAP. The models were not originally developed for the assessment of the West Med MAP and only cover parts of the area of the Western Mediterranean. Such an improvement of the models could also include work to provide longer-term socio-economic assessments of measures where modelers need to take additional assumptions into account. The EWG notes that it would be beneficial if modelers receive a basic list of assumptions for key economic variables before the EWG 23-11 meeting in September. In 2022, for example, the increased fuel costs were an important factor regarding the economic performance of the fleets. In 2023 fuel costs have decreased but there are other cost categories with a substantial increase. The EWG concludes that DG Mare should not change the 6 provided scenarios substantially before the EWG 23-11 meeting in September. This would allow the modelers to run the models during the meeting and provide the socio-economic results. The EWG concludes that STECF and DG Mare should further discuss how resources could be provided to modelers to improve the applied models. The EWG concludes that the chairs of EWG 23-01 and 23-11 will provide a list of assumptions for the implementation of the models regarding key variables for the socio-economic assessments (short- and long-term). For TOR 2 the EWG discussed what variables and indicators the applied models include and provide. From that discussion a list of indicators was developed for which modelers will be able to provide results in the EWG 23-11 report. The EWG concludes that a list of indicators is provided for which EWG 23-11 will present results in autumn 2023. For TOR 3 the EWG notes that new closure areas for 2023 were implemented only by Spain (EMU 1) (Orden APA/80/2023). All closures areas implemented under the West Med MAP are described to allow testing if their implementation would reduce the catches of juveniles and adults of the six target species of the MAP by 15-25%. The EWG notes that the methodology followed to prioritise, developing and updating closure areas based on their conservation value on the basis of existing closures, proposed closures from EWG 22-01 and new proposals developed by EWG 23-01 based on updated MEDISEH layers is similar to the one used during EWG 22- 01. Updated MEDISEH layers were used for priority species (ARA, MUT and HKE) in combination with old MEDISEH layers for other species and distribution maps of commercial effort from EWG 22-01. Calculation of the percentage of the trawlable GSA area closed to fishing is higher in EMU 1 than EMU 2, therefore the estimation of additional closure areas on top of the existing ones foccused on this management unit. Additional closure areas to test were based on persistence hotsposts from survey data and from areas of high effort in order to impact directly on the reduction of fishing mortality. The EWG notes that the exisiting and additional closures could be tested only in EMU 2 and GSA 7 as for GSA 1, 5 and 6 the extension of the spatially-explicit model ISIS-Fish is not complete yet and it is still limited to a single species (HKE). The EWG notes that closure areas in GSA 7 were tested with two different methods. A static method comparing effort distribution data before and after the closures implementation in 2020, and a dynamic method applying ISIS-Fish. The first method showed how the establishment of the spatio-temporal closure imposed a strong seasonal constraint to the fishing effort in the Gulf of Lions, and that the fishermen community responded quite well to the new rule, although vessels increased their fishing effort along the closure border, with a typical « fishing the line » pattern, especially in the fall. The second model showed that introducing an additional closure did not improve the rebuilding of the hake stock, while changing the closures from seasonal to permanent suggested the strongest effect. The EWG notes that in EMU 2 that temporal closures for the whole fleet reduce global effort while additional spatial closures increase effort towards coastal areas (depths

Commission Decision of 25 February 2016 setting up a Scientific, Technical and Economic Committee for Fisheries, C(2016) 1084, OJ C 74, 26.2.2016, p. 4–10. The Commission may consult the group on any matter relating to marine and fisheries biology, fishing gear technology, fisheries economics, fisheries governance, ecosystem effects of fisheries, aquaculture or similar disciplines This report documents the outcomes of STECF Expert Working Group 22-09: 2022 stock assessments of demersal stocks in the western Mediterranean Sea from the meeting held remotely from 5th to 11th September 2022. A total of 20 fish stocks considered and 18 were fully evaluated. Two stocks had prior advice from 2021 with catch advice for 2022 and 2023, and this is reiterated here. The EWG reports age based assessments, target Fs, with short term forecasts for 15 of the remaining 18 stocks, of these 15, 12 were also analysed for biomass reference points. Catch advice for three stocks was based on ICES category three evaluations of biomass indices. The content of the report gives the STECF terms of reference; the basis of the evaluations; assessments, reference point calculations; summaries of state of stock and advised catch or F based on either the MSY approach for assessed stocks and category 3 based advice for those without assessments. The report contains the full stock assessment reports for the 15 assessments, the exploration of assessments and category 3 evaluations for the remaining three stocks. The report also contains the STECF observations and conclusions on the assessment report. These conclusions come from the STECF Plenary meeting November 2022. European Union Published Refereed