The interplay between carbonate production and siliciclastic input produces mixed systems that typically contain a very high degree of lateral and vertical facies heterogeneity. This heterogeneity complicates the sequence stratigraphic analysis of mixed systems. Outcrop studies facilitate the deciphering of controls and understanding of facies distributions within sedimentary successions. The Picún Leufú Anticline in the Neuquén Basin (Argentina) offers the opportunity to integrate large‐scale depositional architecture with detailed facies descriptions of the shelf to basin successions of the Upper Jurassic – Lower Cretaceous Quintuco – Picún Leufú – Vaca Muerta System. The strata in the system are mixed and range in depositional environments from shallow marine sandstones and limestones to deep basinal shales. These environments are arranged in metre‐scale shallowing upward cycles and cycle sets, with increasing carbonate proportions in regressive hemicycles. Increased input of siliciclastic material from the volcanic arc area occurred during phases of relative sea‐level rise and was controlled by the intensity of along‐shelf currents. The shelf transport was driven by the available accommodation space on the shelf, and therefore was a function of the eustatic sea‐level fluctuations. Within the studied section, a pure carbonate depositional system developed because siliciclastic input was shut down either due to long‐lived highstand settings or a sudden climatic change to more arid conditions. Carbonate–siliciclastic mixing in this setting is a function of siliciclastic dilution of the carbonate sedimentation and differs from the classical reciprocal sedimentation model, which typically includes shut‐off of carbonate production during lowstand periods. In the regional context, the subsurface strata of time‐equivalent reservoirs in the Eastern Neuquén Embayment display strong similarities of architecture, indicating that similar mixing processes occurred along most of the Neuquén Basin.

Chemical recycling of plastic wastes can be a useful complement to mechanical recycling to achieve the required plastics recycling rates and to establish a circular economy that is climate neutral and resource‐efficient. Different mixed plastic wastes that are subject to future recycling efforts are studied under uniform conditions of intermediate pyrolysis characterized by a medium heating rate and pyrolysis temperature. Product distributions and selected product properties are determined, and process mass and energy balances are derived. Product yields and compositions are highly dependent on the waste pyrolyzed. The results show that pyrolysis is a suitable process to recover chemical feedstock from various complex mixed plastic wastes.

The Middle Permian to Lower Triassic Khuff Formation is one of the most important reservoir intervals in the Middle East. This study presents a sequence stratigraphic analysis of the Khuff Formation of a well-exposed outcrop in the Oman Mountains, which may provide a reference section for correlations across the entire Middle East. On the Saiq Plateau of the Al Jabal al-Akhdar, the Permian Upper Saiq Formation is time-equivalent to the Lower and Middle Khuff Formation (K5–K3 reservoir units in Oman). The Permian section is dominated by graded skeletal and peloidal packstones and cross-bedded grainstones with a diverse marine fauna. The Lower Mahil Member (Induan Stage), time-equivalent to the Upper Khuff Formation (K2–K1 reservoir units in Oman), is dominated by grainstones composed of microbially-coated intra-clasts and ooids. In general, the studied outcrop is characterized by a very high percentage of grain-dominated textures representing storm-dominated shoal to foreshoal deposits of a paleogeographically more distal portion of the Khuff carbonate ramp. A sequence-stratigraphic analysis was carried out by integrating lithostratigraphic marker beds, facies cycles, bio- and chemostratigraphy. The investigated outcrop section was subdivided into six third-order sequences, named KS 6 to KS 1. KS 6–KS 5 are interpreted to correspond to the Murgabian to Midian (ca. Wordian to Capitanian) stages. KS 4-Lower KS 2 correspond to the Dzhulfian (Wuchiapingian) to Dorashamian (Changhsingian) stages. Upper KS 2–KS 1 represent the Triassic Induan stage. Each of the six sequences was further subdivided into fourth-order cycle sets and fifth-order cycles. The documentation of this outcrop may contribute to a better regional understanding of the Khuff Formation on the Arabian Platform.

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Three thousand liters of water were infiltrated from a 4 m diameter pond to track flow and transport inside fractured carbonates with 20-40 % porosity. Sixteen time-lapse 3D Ground Penetrating Radar (GPR) surveys with repetition intervals between 2 hrs and 5 days monitored the spreading of the water bulb in the subsurface. Based on local travel time shifts between repeated GPR survey pairs, localized changes of volumetric water content can be related to the processes of wetting, saturation and drainage. Deformation bands consisting of thin subvertical sheets of crushed grains reduce the magnitude of water content changes but enhance flow in sheet parallel direction. This causes an earlier break through across a stratigraphic boundary compared to porous limestone without deformation bands. This experiment shows how time-lapse 3D GPR or 4D GPR can non-invasively track ongoing flow processes in rock-volumes of over 100 m 3 •

The Middle Permian to Lower Triassic Khuff Formation is one of the world's most prolific hydrocarbon reservoirs. This study is part of a research project on Khuff outcrop equivalents whose overall aim is to investigate the reservoir architecture on different scales. The present paper focuses on heterogeneities in Khuff-equivalent grainstones at the near well scale.An outcrop in the Oman Mountains, where the Khuff-equivalent Saiq and Mahil Formations are exposed in an area 1800 m long by 100 m high, was studied to map lateral and vertical depositional heterogeneities. The investigated section represents parts of three third-order sequences: the upper part of Khuff sequence (KS)3 (grain-dominated), the whole of KS2 (muddominated), and the lower part of KS1 (grain-dominated). Real-Time Kinematic GPS, satellite imagery, outcrop gamma-ray and digitized sedimentary logs were used for outcrop description and were integrated into a three-dimensional digital outcrop model.The resulting 3D facies model indicates that the apparently simple, layer-cake geometry of the grainstone reservoir facies shows pinching and swelling with a standard deviation of 12.75% of bed thickness. These thickness variations may influence volume calculations during reservoir assessments. The heterogeneities of grainstone bodies are represented by compositional (ooid, peloid or intraclast-dominated) and grain-size variations.Muddy event beds at the cm-scale were mapped out in detail in a 200 x 40 m outcrop window and together form a dense network of potential baffles to fluid flow. The thickness of these beds varies significantly due to syndepositional erosion.An important conclusion of this near well-scale study is that the perceived simple, layer-cake Khuff-equivalent succession in the study area is in fact heterogeneous in mud-rich deposits, while grain-rich deposits extend over a wide area with some thickness variations. These findings can be directly applied in Khuff subsurface correlation and modelling attempts.

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The global economy and its production chains must move away from petroleum-based products, to achieve this goal, alternative carbon feedstocks need to be established. One area of concern is sustainable production of synthetic lubricants. A lubricating oil can be described as a high boiling point (>340 °C) liquid with solidification at least below room temperature. Historically, many lubricants have been produced from petroleum waxes via solvent or catalytic dewaxing. In this study, catalytic dewaxing was applied to potential climate neutral feedstocks. One lubricant was produced via Fischer–Tropsch (FT) synthesis and the other lubricant resulted from low temperature pyrolysis of agricultural waste plastics. The waxes were chosen because they each represented a sustainable alternative towards petroleum, i.e., FT waxes are contrivable from biomass and CO2 by means of gasification and Power-to-X technology. The pyrolysis of plastic is a promising process to complement existing recycling processes and to reduce environmental pollution. Changes in cloud point, viscosity, and yield were investigated. A bifunctional zeolite catalyst (SAPO-11) loaded with 0.3 wt% platinum was used. The plastic waste lubricants showed lower cloud points and increased temperature stability as compared with lubricants from FT waxes. There was a special focus on the composition of the naphtha, which accumulated during cracking. While the plastic waste produced higher amounts of naphtha, its composition was quite similar to those from FT waxes, with the notable exception of a higher naphthene content.