ExxonMobil (Qatar)

ABSTRACT Organic-rich rocks have long been recognized as source rocks for clastic reservoirs, but more recently they have gained importance as reservoirs. However, the processes of kerogen maturation and hydrocarbon transport and storage are still poorly understood. Some empirical relations have been developed to relate the increase in elastic modulus with increasing maturity. A systematic study of the cause for this increase in elastic modulus is still lacking, and information about seismic and mechanical properties of kerogen and its alteration products is scarce. Consequently, any rock models must rely on anecdotal or extrapolated data about various types of kerogen. Our experiments address this paucity of data by grain-scale modulus measurements coupled with careful field emission scanning electron microscopy (FESEM) microstructural assessments on organic rich Bakken formation shale samples with a range of maturities. Carefully acquired and detailed FESEM images help to understand the microstructural controls on the reduced (nanoindentation) Young’s modulus of minerals, clay particles, and kerogen matter with maturity in naturally matured shales. Using hydrous pyrolysis, we further investigate the cause for change in modulus with maturity and the mobility of the pyrolized organic matter. In naturally matured shale samples, we find a direct relationship between the reduced Young’s modulus and the total organic content or hydrogen index. Significant lowering of Young’s modulus is observed after hydrous pyrolysis due to bitumen generation. We measured modulus of the extruded bitumen to be less than 2 GPa. The presence of bitumen comingled with the organic matter also reduces its modulus, in excess of 30%. These results are critical to help understand how organic-rich sediments evolve with burial and maturation. The modulus measurements can be used for modeling modulus variations during maturation.

Purpose The study aims to explore why consumers engage with ordinary celebrities on social media by identifying the influential characteristics that have engaged followers and have led to opinion leadership on visual platforms, such as Instagram and Facebook. Design/methodology/approach Qualitative data were collected from 32 social media users following at least one ordinary celebrity on Instagram and Facebook in Qatar and Tunisia. Findings The findings of this study highlight five main characteristics that lead to fame and opinion leadership on social media visual platforms: credibility, storytelling and content quality, fit with the platform, Actual and aspired image homophily and consistency. Research limitations/implications This research is, to the best of the authors’ knowledge, one of the first studies that highlight the features determining opinion leadership on visual platforms such as Instagram and Facebook. Second, the results of the study highlight some features that distinguish ordinary celebrities from traditional established celebrities. Practical implications The findings of this research represent a guideline for effective influential marketing development. Based on the results, recommendations are provided for companies, influencers and social media users who aspire to become influencers. Originality/value This research, to the best of the authors’ knowledge, is among the first to shed light on opinion leadership through ordinary celebrities on visual social media platforms, such as Facebook and Instagram, and thus, adds new insights to the area of social media marketing.

Abstract Volatile and stable isotope data provide tests of mantle processes that give rise to mantle heterogeneity. New data on enriched mid‐oceanic ridge basalts (MORB) show a diversity of enriched components. Pacific PREMA‐type basalts (H 2 O/Ce = 215 ± 30, δD SMOW = −45 ± 5 ‰) are similar to those in the northern Atlantic (H 2 O/Ce = 220 ± 30; δD SMOW = −30 to −40 ‰). Basalts with EM‐type signatures have regionally variable volatile compositions. Northern Atlantic EM‐type basalts are wetter (H 2 O/Ce = 330 ± 30) and have isotopically heavier hydrogen (δD SMOW = −57 ± 5 ‰) than northern Atlantic MORB. Southern Atlantic EM‐type basalts are damp (H 2 O/Ce = 120 ± 10) with intermediate δD SMOW (−68 ± 2 ‰), similar to δD SMOW for Pacific MORB. Northern Pacific EM‐type basalts are dry (H 2 O/Ce = 110 ± 20) and isotopically light (δD SMOW = −94 ± 3 ‰). A multistage metasomatic and melting model accounts for the origin of the enriched components by extending the subduction factory concept down through the mantle transition zone, with slab temperature a key variable. Volatiles and their stable isotopes are decoupled from lithophile elements, reflecting primary dehydration of the slab followed by secondary rehydration, infiltration, and re‐equilibration by fluids derived from dehydrating subcrustal hydrous phases (e.g., antigorite) in cooler, deeper parts of the slab. Enriched mantle sources form by addition of <1% carbonated eclogite ± sediment‐derived C‐O‐H‐Cl fluids to depleted mantle at 180–280 km (EM) or within the transition zone (PREMA).

Polycyclic aromatic hydrocarbons (PAHs) are one of the most frequent petroleum hydrocarbons detected in the environment. PAHs are receiving global attention due to their toxicity, environmental persistence, and potential bioaccumulation. PAHs contamination occurs mainly due to anthropogenic sources related to the disposal of industrial and domestic run-offs or atmospheric emissions from plants or vehicles. Once PAHs are introduced into the environment, they undergo different processes either physical, chemical, or biological transformations, which are collectively known as weathering processes. These weathering processes are highly dependent on the nature and the physiochemical properties of PAHs molecules and the surrounding environment, which eventually will determine their transport, fate, and distribution in the environment either through adsorption to soil/sediments, or volatilization to the atmosphere, or dissolution in the water. Different treatment strategies for PAHs pollution have been introduced. Each remediation technology has its advantages and disadvantages. To choose a treatment, a full analysis of the case study should be provided, including the properties of the target pollutant, site description, and treatment procedure. As the treatment of PAHs contaminated sites is usually a difficult and expensive task, it would be a good choice to go for treatment, which is adaptive, sustainable, eco-friendly, efficient, and cost-effective. In this review, the transport, fate, and distribution processes of PAHs in the environment with their dependent factors were elaborated. In addition, this paper provided an overview of different traditional and advanced potential treatment approaches used to treat PAHs-contaminated sites such as thermal, chemical, electrokinetic, nano-adsorption, and biological treatments.

In recent years, the increased demand for and regional variability of available water resources, along with sustainable water supply planning, have driven interest in the reuse of produced water. Reusing produced water can provide important economic, social, and environmental benefits, particularly in water-scarce regions. Therefore, efficient wastewater treatment is a crucial step prior to reuse to meet the requirements for use within the oil and gas industry or by external users. Bioremediation using microalgae has received increased interest as a method for produced water treatment for removing not only major contaminants such as nitrogen and phosphorus, but also heavy metals and hydrocarbons. Some research publications reported nearly 100% removal of total hydrocarbons, total nitrogen, ammonium nitrogen, and iron when using microalgae to treat produced water. Enhancing microalgal removal efficiency as well as growth rate, in the presence of such relevant contaminants is of great interest to many industries to further optimize the process. One novel approach to further enhancing algal capabilities and phytoremediation of wastewater is genetic modification. A comprehensive description of using genetically engineered microalgae for wastewater bioremediation is discussed in this review. This article also reviews random and targeted mutations as a method to alter microalgal traits to produce strains capable of tolerating various stressors related to wastewater. Other methods of genetic engineering are discussed, with sympathy for CRISPR/Cas9 technology. This is accompanied by the opportunities, as well as the challenges of using genetically engineered microalgae for this purpose.

This study characterized and assessed three different process water (PWWs) (S-1, S-2, and S-3) from oil and gas production in Qatar. The wastewater generated in various processing stages contains many harmful components including polyaromatic hydrocarbons, phenol, heavy metals, ammonia, and other hydrocarbons and non-hydrocarbons. The results revealed that S-2 had higher pH (8.5) followed by S-3 (8.3) and S-1 (7.8). Lastly, S-1 reported the highest concentration of gasoline range organics (GRO) and extractable petroleum hydrocarbons (EPH), and polycyclic aromatic hydrocarbons (PAHs) followed by S-2 and S-3. In addition, biological oxygen demand (BOD) was the highest in S-1 44,300 mg/L followed by S-2 and S-3 26,300 and 14,600 mg/L, respectively. Moreover, salinity was also the highest in S-3 at 260 ppt, followed by S-2 at 38.2 ppt and S-1 at 38.9. Overall, S-1 reported the highest concentration of GRO, EPH, and all PAHs followed by S-2 and S-3. Additionally, the PWWs consisted of high organic containing wastes. The results also revealed that all three PWWs were enriched with zinc and iron, and sixteen different hydrocarbon compounds were identified, amongst which acenaphthene, acenaphthylene, fluorene, anthracene, phenanthrene, benzo(a)anthracene, and pyrene were dominating in all three samples.

Qatar is one of the biggest oil and gas producers in the world, coupled with it is challenging environmental conditions (high average temperature: >40 °C, low annual rainfall: 46.71 mm, and high annual evaporation rate: 2200 mm) harbors diverse microbial communities that are novel and robust, with the potential to biodegrade hydrocarbons. In this study, we collected hydrocarbon contaminated sludge, wastewater and soil samples from oil and gas industries in Qatar. Twenty-six bacterial strains were isolated in the laboratory from these samples using high saline conditions and crude oil as the sole carbon source. A total of 15 different bacterial genera were identified in our study that have not been widely reported in the literature or studied for their usage in the biodegradation of hydrocarbons. Interestingly, some of the bacteria that were identified belonged to the same genus however, demonstrated variable growth rates and biosurfactant production. This indicates the possibility of niche specialization and specific evolution to acquire competitive traits for better survival. The most potent strain EXS14, identified as Marinobacter sp., showed the highest growth rate in the oil-containing medium as well as the highest biosurfactant production. When this strain was further tested for biodegradation of hydrocarbons, the results showed that it was able to degrade 90 to 100% of low and medium molecular weight hydrocarbons and 60 to 80% of high molecular weight (C35 to C50) hydrocarbons. This study offers many promising leads for future studies of microbial species and their application for the treatment of hydrocarbon contaminated wastewater and soil in the region and in other areas with similar environmental conditions.

Abstract High-effort three-dimensional (3-D) seismic data collected by the Abu Dhabi Company for Onshore Oil Operations (ADCO) are some of the highest quality data ever collected for a carbonate field. The 3-D seismic data were integrated with core and log data to develop a new, volume-based framework for enhanced reservoir characterization. The Lower Cretaceous (Aptian) reservoir is positioned over a platform-to-basin transition and records a diverse range of depositional facies and stratal geometries. Reservoir properties vary predictably based on position along the platform-to-basin profile and position in the sequence-stratigraphic framework. The Aptian reservoir interval (Shuaiba Formation) records a second-order sequence set that is divided into five depositional sequences. Sequences 1 and 2 were deposited during the transgressive phase of the sequence set. These sequences are retrogradational, record the initial formation of a low-relief ramp, and are dominated by algal-prone facies. Ramp interior and margin facies of the transgressive phase are characterized by high porosity and low permeability because of mud-dominated textures and development of microporos-ity. Sequence 3 was deposited during the highstand phase of the sequence set, is mainly aggradational, and records the proliferation or rudists across the platform top. Grain-dominated platform interior and margin facies of the highstand phase are the highest quality reservoir facies in the Shuaiba reservoir. Sequences 4 and 5 were deposited during the late highstand phase of the sequence set. These sequences are progradational and record the progressive downstepping of the platform margin onto a low-angle (1-2°) slope. Clino-forms of the late highstand phase are characterized by alternations of high and low reservoir quality developed in response to relative sea level changes. Sequence 6 was deposited during the second-order lowstand and forms the base of the next overlying sequence set. Sequence 6 is composed primarily of finegrained siliciclastics and is a nonreservoir. Results from the study have led to an improved understanding of platform evolution and a volume-based framework for reservoir characterization. The integrated data set provides new insights on platform paleogeography, carbonate facies architecture, and the geometry and mechanisms of carbonate platform progradation. In the platform interior area, 3-D seismic data reveal a complex mosaic of tidal channels, high-energy rudist shoals, and intershoal ponds that impact reservoir sweep and conformance. At the basin margin, the seismic data provide high-definition images of platform-margin clinoforms that impact reservoir architecture and well-pair connectivity. Business applications of the volume-based reservoir framework include (1) use of 3-D seismic visualization technology for optimizing well placement, identifying bypassed reservoirs, and evaluating reservoir connectivity; (2) integration of quantitative, volume-based seismic information into reservoir models; (3) maximizing recovery through full integration of all subsurface data; and (4) enhanced communication among geoscientists and engineers, leading to improved reservoir management practices.

Abstract The upper Palaeocene–lower Eocene Umm er Radhuma Formation in the subsurface of Qatar is dominated by subtidal carbonate depositional packages overlain by bedded evaporites. In Saudi Arabia and Kuwait, peritidal carbonate depositional sequences with intercalated evaporites and carbonates in Umm er Radhuma have been previously interpreted to have been dolomitized via downward reflux of hypersaline brines. Here, textural, mineralogical and geochemical data from three research cores in Qatar are presented which, in contrast, are more consistent with dolomitization by near‐normal marine fluids. Petrographic relationships support a paragenetic sequence whereby dolomitization occurred prior to the formation of all other diagenetic mineral phases, including chert, pyrite, palygorskite, gypsum, calcite and chalcedony, which suggests that dolomitization occurred very early. The dolomites occur as finely crystalline mimetic dolomites, relatively coarse planar‐e dolomites, and coarser nonplanar dolomites, all of which are near‐stoichiometric (50.3 mol% Mg CO 3 ) and well‐ordered (0.73). The dolomite stable isotope values (range −2.5‰ to +1‰; mean δ 18 O = −0.52‰) and trace element concentrations (Sr = 40 to 150 ppm and Na = 100 to 600 ppm) are compatible with dolomitization by near‐normal seawater or mesohaline fluids. Comparisons between δ 18 O values from Umm er Radhuma dolomite and the overlying Rus Formation gypsum further suggest that dolomitization did not occur in fluids related to Rus evaporites. This study provides an example of early dolomitization of evaporite‐related carbonates by near‐normal seawater rather than by refluxing hypersaline brines from overlying bedded evaporites. Further, it adds to recent work suggesting that dolomitization by near‐normal marine fluids in evaporite‐associated settings may be more widespread than previously recognized.

Metal pollution in sediments has long been recognized, while sediments are also a long-term sink for microplastics (MPs). MPs may also adsorb environmental pollutants, including metals, as well as leaching polymer components and chemicals used during production. A comprehensive survey of 21 locations around Qatari coastline investigated abundance of MPs in high-shore intertidal sediments and concentration of metals both on MPs and sediment particles. MPs abundance ranged from 3 to 156 MPs particles·kg−1 (12–624 MPs particles·m−2) with polyethylene being the most abundant (27.4 %). MPs showed physical morphologies, with 76 % displayed signs of chemical degradation as confirmed by the carbonyl absorption peak profile, possibly due to exposure to harsh environmental conditions on the Arabian Gulf shores. Most metals analyzed were found at higher concentrations in sediments than the same metals adsorbed to MPs. The average metal concentration ranged from 0.26 (Cd) to 3122.62 μg∙g−1 (Sr) in sediments while 0.22 (Mo) to 30.26 μg∙g−1 (Sr) in MPs. The calculated metal Pollution Load Index (Sed PLI, range 0.57–2.38) for sediments indicates unpolluted to moderately polluted levels, while the Potential Ecological Risk Index (Sed PERI, range 6.9–2220) indicates a relatively considerable ecological risk for metal pollution in sediments in some of the coastal areas surveyed. PLI values calculated for metals associated with MPs (MPs PLI, range 1.1–7.5), suggests relatively moderate pollution, while the PERI for metals in MPs (MPs PERI, range 25.2–1811) has similar ecological risk in terms of metal pollutants in MPs as for sediments. This may be effective in providing relative spatial indices of pollution load and risk for metals associated with MPs, which could potentially inform establishment of an appropriate assessment framework, where MPs are increasingly abundant in coastal sediments. However, this does not account for the relatively lower abundance of MPs compared to sediments.

This article presents a new model for constructing weekly schedules for therapists who treat patients with fixed appointment times at various healthcare facilities throughout a large geographic area. The objective is to satisfy the demand for service over a 5-day planning horizon at minimum cost subject to a variety of constraints related to time windows, overtime rules, and breaks. Each therapist works under an individually negotiated contract and may be full-time or part-time. Patient preferences for specific therapists and therapist preferences for assignments at specific facilities are also taken into account when they do not jeopardize feasibility. To gain an understanding of the computational issues, the complexity of various relaxations is examined and characterized. The results indicated that even simple versions of the problem are NP-hard. The model takes the form of a large-scale mixed-integer program but was not solvable with CPLEX for instances of realistic size. Subsequently, a branch-and-price-and-cut algorithm was developed and proved capable of finding near-optimal solutions within 50 minutes for small instances. High-quality solutions were ultimately found with a rolling horizon algorithm in a fraction of that time. The work was performed in conjunction with Key Rehab, a company that provides physical, occupational, and speech therapy services throughout the U.S. Midwest. The policies, practices, compensation rules, and legal restrictions under which Key operates are reflected in the model formulation.

Abstract Palygorskite is a fibrous, magnesium‐bearing clay mineral commonly associated with Late Mesozoic and Early Cenozoic dolomites. The presence of palygorskite is thought to be indicative of warm, alkaline fluids rich in Si, Al and Mg. Palygorskite has been interpreted to form in peritidal diagenetic environments, either as a replacement of detrital smectite clay during a dissolution–precipitation reaction or solid‐state transformation, or as a direct precipitate from solution. Despite a lack of evidence, most diagenetic studies involving these two minerals posit that dolomite and palygorskite form concurrently. Here, petrological evidence is presented from the Umm er Radhuma Formation (Palaeocene–Eocene) in the subsurface of central Qatar for an alternative pathway for palygorskite formation. The Umm er Radhuma is comprised of dolomitized subtidal to peritidal carbonate cycles that are commonly capped by centimetre‐scale beds rich in palygorskite. Thin section, scanning electron microscopy and elemental analyses demonstrate that palygorskite fibres formed on both the outermost surfaces of dissolved euhedral dolomite crystals and within partially to completely dissolved dolomite crystal cores. These observations suggest that dolomite and palygorskite formed sequentially, and support a model by which the release of Mg 2+ ions and the buffering of solution pH during dolomite dissolution promote the formation of palygorskite. This new diagenetic model explains the co‐occurrence of palygorskite and dolomite in the rock record, and provides valuable insight into the specific diagenetic conditions under which these minerals may form.

Abstract Organic-rich shales (ORS) are common source rocks for most clastic reservoirs. More recently, they have gained importance as reservoirs. However, the processes of kerogen maturation, hydrocarbon storage, and hydrocarbon transport are still poorly understood. Empirical relations have been developed to relate the increase in acoustic velocity and elastic modulus with increasing maturity. The reason for this increase in velocity also remains poorly understood. We conducted experiments on ORS samples with a range of maturities from the Bakken formation. Our study focuses on investigating methods of predicting maturity of ORS by evaluation of their impedance micro-structure. Our Young’s modulus measurements on a nanometer scale help understand variations of Young’s modulus of minerals, clay particles, and kerogen matter in naturally matured shales. The samples were re-measured after subjecting them to hydrous pyrolysis. This step helped us investigate the cause for change in modulus with maturity and the mobility of the pyrolysed organic matter. In the naturally matured samples, we find direct qualitative relationships between the Young’s modulus of shale samples and its maturity indicators, such as TOC and Transformation Ratio. After hydrous pyrolysis, there is a significant lowering of the Young’s modulus in some immature samples. We will present results of elastic property changes before and after hydrous pyrolysis in shales of various maturities. This study improves our current understanding of maturity-related variations by using analysis from nanoindentation. We integrate these measurements with geochemical analysis, and observations from downhole sonic measurements to develop relationships of elastic impedance to shale maturity. These results are critical to help us understand how shales evolve with burial and maturation and how hydrocarbons are stored and transported to sustain large storage even at high overburden stresses.

Abstract Recrystallization of dolomite can alter textural, mineralogical and geochemical attributes used to infer environmental conditions of initial dolomitization. A meta‐analysis of the published literature shows that extensive recrystallization is most common in old and deeply buried dolomites, but data from the Palaeocene–Eocene Umm er Radhuma Formation in Qatar show that this can also happen in geologically young carbonates that have never been deeply buried. Evidence of extensive recrystallization comes from a principal component analysis of published mineralogical and geochemical data that are integrated with new clumped isotope (∆ 47 ) measurements and cathodoluminescence petrography. The observations indicate that dolomite stoichiometry and cation ordering correlate with dolomite texture and depth: shallow mimetic dolomites are less stoichiometric and poorly‐ordered whereas coarser and deeper planar‐e and planar‐s to nonplanar dolomites with mottled cathodoluminescence signatures are more stoichiometric and well‐ordered, suggesting they have recrystallized. Dolomite δ 18 O data (Vienna Pee Dee Belemnite) also covary with texture, as mimetic dolomites have the narrowest range (−0.45‰ to +0.38‰), planar‐e dolomites are generally ≤0‰ (−2.4‰ to +0.68‰) and planar‐s to nonplanar dolomites exhibit the widest range (−2.3‰ to +1.4‰). The principal component analysis results indicate one component with positive loadings for dolomite stoichiometry (+0.752) and cation ordering (+0.813), and negative loading for δ 18 O (−0.833), trends predicted in recrystallized dolomites. The ∆ 47 ‐derived temperatures (32 to 46°C) and δ 18 O w (+0.18 to +2.6‰ Vienna Standard Mean Ocean Water) reflect recrystallization by warm, slightly evaporated seawater at shallow depths. In the context of a meta‐analysis of recrystallized dolomites in the literature, this study implies that extensive dolomite recrystallization in Cenozoic dolomites and shallow‐burial conditions is an under‐appreciated phenomenon. The results of this study also demonstrate that initial petrological attributes can be significantly altered after dolomitization, hindering interpretations of past seawater chemistry and environmental conditions of dolomitization.

A comprehensive, high resolution, ground truthed benthic habitat map has been completed for Qatar's coastal zone and Halul Island. The objectives of this research were to; 1. Systematically compare and contrast pixel- and object-based classifiers for benthic mapping in a limited focus area and then to, 2. Apply these learnings to develop an accurate high resolution benthic habitat map for the entirety of the Qatari coastal zone. Results indicate object-based methods proved more efficient and accurate when compared to pixel based classifiers. The developed country-wide map covers 4500 km2 and underscores the complex interplay of seagrass, macroalgal, and reefal habitats, as well as areas of expansive mangrove forests and microbial mats. The map developed here is a first of its kind in the region. Many potential applications exist for the datasets collected to provide fundamental information that can be used for ecosystem-based management decision making.

Abstract SMI 36 is a predominantly gas field on the Gulf of Mexico shelf. The principal trap is updip fault closure in the hanging wall of a large down-to-the-north normal fault. A second normal fault, the intrareservoir fault, separates the reservoir into two compartments. Juxtaposition (Allan) diagrams of the stratigraphy projected onto this intrareservoir fault surface show several intervals of sand-on-sand juxtaposition. In the lowermost part of the section, the MA sand in the footwall is juxtaposed against the LN and LP sands in the hanging wall. Differential fluid contacts and pressures in these sands across this fault suggest that the fault is sealing. We hypothesize shale gouge as the mechanism for fault seal. Estimates of shale percent along the fault plane between the sand intervals range between 40 and 80%. Mud weights and limited reservoir pressure data show that the deep section is overpressured with a water pressure differential as much as 600 psi (4.13 × 106 Pa) across the fault. The cross-fault differences in the aquifer pressure partially seal the hydrocarbons in the hanging wall. The hydrocarbons in the footwall reservoir support a capillary pressure as much as 80 psi (5.51 × 105 Pa) for a shale gouge of 45%. Production pressure profiles record a cross-fault pressure difference of 3000 psi (2.06 × 107 Pa) across the fault before pressure support between the reservoirs suggesting seal “breakdown.”

The southern margin of the Arabian Gulf is a ''classic'' shallow-water, evaporative, carbonate-producing setting. The sediments and early diagenetic products creating the ''Great Pearl Bank'' of the United Arab Emirates to the east and accumulating in the coastal regions of Qatar to the west have long been studied as modern analogs for ancient evaporitic carbonate deposits of the rock record. An integrated study measuring the chemistry of Qatar subtidal coastal waters, evaporating tidal-pond waters (to halite saturation), and meteoric pond waters was undertaken encompassing both the dry (fall) and wet (winter/spring) seasons of 2016-2017. Measured parameters included temperature, pH, dissolved oxygen, and alkalinity, as well as major-ion (Na , Ca 2 , Mg 2 , K , Sr 2 , Cl -, and SO 4 2-

Abstract In March 2005, the operator implemented a rate of penetration (ROP) management process in Qatar's North Field. IPTC Paper 10706-PP describes the general principles behind the new work process and highlights its introduction to the operator. The ROP management process uses real time, customized surveillance technology to continuously maximize both drill bit cutter efficiency and transmission of energy from rig floor to the bit. This paper focuses on specific changes in drilling practices and their translation into substantive program acceleration and capital savings. To date, the development program has been accelerated by one year and USD 54 million has been saved while drilling 470,000 ft of hole. The process has proven to be a highly effective solution for management of drilling efficiency in a major development drilling campaign. As an indicator of program scope and effectiveness, over 440 personnel have been trained in mechanical specific energy (MSE) analysis, and 50 new field drilling records have been set by the nine rigs involved in the program. Importantly, the process has been implemented with one of the best safety records in industry (TRIR or total recordable incident rate of 0.11 per 200,000 man-hours as of September 06).

The Khor Al Adaid embayment of southern Qatar represents a unique shallow-water mixed siliciclastic‑carbonate coastal depositional system that developed in a hyper-arid climatic setting over the past 6000 years. The embayment, which was formed during the Flandrian transgression as a result of flooding across a partially fault-controlled incised fluvial drainage, is supplied by quartz-rich sands delivered by wind-blown dunes migrating southward across the surface of Qatar. These offshore-migrating eolian-derived sediments are being redistributed by tidal currents in an otherwise low-energy coastal zone, where in situ formation of carbonate mud and a low-diversity skeletal assemblage is ongoing within salinity-restricted environments. Three depositional sectors are delineated: 1) an energetic, linear, fault-controlled Entrance Channel into which the eolian dunes spill directly; 2) a relatively deep (up to 20 m) Outer Lagoon, interpreted to represent a flooded karst-collapse structure; and 3) a sprawling, low-energy, shallow (<2 m) Inner Lagoon occupying low-lying areas between deflated eolian dunes. Physical oceanographic modeling, integrating multi-seasonal current meter and tidal gage measurements, demonstrates tidal current flow velocities are relatively high in both the Entrance Channel and at the constricted entrance to the Inner Lagoon. Associated flow expansion into less confined areas results in deposition of the eolian-derived sands as flood-tidal deltas, one in the Outer, and two in the Inner Lagoon. A weakly-developed ebb-tidal delta occurs where the Entrance Channel debouches into the Arabian Gulf. Flood-tide dominance is also apparent in Entrance Channel deposits, where sand accumulates in seaward-terminating “ebb barbs” along the margins of the flood-dominant thalweg. Such flood-tide dominance of the thalweg is unusual and likely reflects the absence of river discharge. Evidence of significant inverse estuarine circulation (seaward flow of a brine along the embayment floor) is mostly absent in spite of the landward increase of salinity, where concentrations reach more than double normal seawater salinity in the Inner Lagoon. Modeling results show that seaward-flowing brines formed in the Inner Lagoon are trapped in the relatively deep Outer Lagoon, and that mixing by tidal currents in the energetic Entrance Channel precludes the formation of vertical density gradients there. Because siliciclastic mud is essentially absent, and most of the sediment forming the deltas consists of sand, upper intertidal deltaic deposits that would normally consist of mud are absent, resulting in the flood-tide deltas having a pronounced lobate geometry similar to that of fluvial deltas formed predominantly of sand. Away from tidal deltas, low-energy lagoons are floored by carbonate mud of local production, with minor gypsum precipitating in the Inner Lagoon. Wind-generated waves only locally influence sedimentation, forming complex nearshore bars along some lagoonal shorelines. The overall landward increase in salinity is accompanied by a decrease in the diversity of benthic fauna and their skeletal remains. A fairly diverse faunal assemblage is observed in the Entrance Channel near the Arabian Gulf, including colonial corals, whereas the inner lagoon assemblage is dominated gastropods belonging to Pirenella cingulata. The remnants of large eolian dunes are preserved in the low-energy setting of the Inner Lagoon, segmenting the waterbody, and locally increasing restriction. The sedimentology of the arid-zone coastal Khor Al Adaid embayment may serve as an analogue for environmental settings that were perhaps more commonplace in arid zones of flooded continents during greenhouse times.

Abstract Offshore deepwater discoveries have driven the development of new compactseparation technologies, a core aspect of subsea processing. Compact separatorsare much smaller than conventional separators and have the potential tosignificantly reduce capital expenditure for deepwater developments. Unfortunately, reducing the size of separators generally reduce the separationperformance and the robustness to handle fluctuations in flow rate andcomposition. It is therefore essential to find an acceptable balance betweenthe realized reduction in overall capital expenditure and reduced tolerance tofluctuating conditions. To maximize the economics of a subsea development, itis important to understand how the technology selection impacts performance, risks, costs, and ultimately the attractiveness of deepwater subsea processing. Proactive technology screening and qualification are required. This paperpresents one of several ongoing joint industry projects to develop and screenseparation technologies for deepwater applications, the DEMO 2000 project: NextGeneration Deepwater Subsea Gas-liquid Separation System. An overview ofavailable technologies for separation in deep water is disclosed, includingcyclonic separators, compact gravity-type separators, and slug dampeningtechnologies. Their characteristics, typical performance and maturity level arediscussed. Finally, the program activities are explained and some highlightsfrom the separation test program are shared. Introduction Value Drivers for Subsea Gas-liquid Separation In recent years, subsea processing, and more specifically subsea separation, has been recognized as one of the most promising technology developments in theoffshore industry. With the recent success at Perdido [Ju et al., 2010], Parquedas Conchas (BC-10) [Iyer et al., 2010; Deuel et al., 2011], and Pazflor[Eriksen, 2012], subsea separation is attracting interest from industry becauseof its ability to increase production, enhance recovery, and improve fieldeconomics on a commercial scale. Subsea separation is, in general, stillconsidered an emerging technology area; therefore the benefits and capabilitiesmust be clearly demonstrated to infuse acceptance and confidence as thepreferred development option. McClimans and Fantoft [2006] and Di Silvestro etal. [2011] have presented a detailed review of the value drivers for subseagas-liquid separation, which is the topic of this paper. In summary, subseagas-liquid separation has proven to provide strong business incentives withenabling capabilities, including (i) more efficient liquid boosting, (ii)longer range gas compression from subsea to onshore, (iii) cost efficienthydrate management, (iv) effective riser slug depression, (v) and access tochallenging field developments that otherwise would be abandoned or notdeveloped (due to their remote location, harsh conditions, longer tie-backrequirements, or low reservoir drive). The main drivers are discussedbelow.