Workshop Sessions:
Session 1: Stratigraphy and Sedimentology of Source Rocks in the Middle East Region
Lying at the core of the world-class Middle Eastern hydrocarbon province is a series of exceptional hydrocarbon source rocks, with a broad range of ages, kerogen types, and organo-facies, deposited in a range of geological environments. Proven source rocks for much of the conventional oil, gas, and condensate volumes discovered to date include the glacial to post-glacial Neoproterozoic to Early Cambrian syn-rift source rocks of Oman; the regionally extensive, marine transgressive intervals of the Lower Silurian; and the Tethyan shallow carbonate intra-basinal settings of the Middle to Late Jurassic and Middle Cretaceous. In contrast to the conventional reservoirs targeted to date, unconventional reservoirs generally lack well-defined hydrocarbon-water contacts and include self-sourcing oil and gas shale deposits, coal-bed methane, and some tight sandstone reservoirs. While the organic richness, kerogen types and maturity of these source rocks are generally well understood, the role of these organic-rich intervals and their associated facies as unconventional reservoir targets remains poorly defined on all scales. While a strong focus on the depositional settings, thickness variations, porosity-permeability characteristics, and pressure regimes are important, a more detailed understanding of the mineralogy, lithological variations, brittleness, natural fracture distributions, and stress regimes is key to accessing this untapped potential.
Recently many national oil companies have started to explore and evaluate the potential of making those source rocks economical, while others are yet to start these studies.
This session provides the ideal setting for describing the lithological, sedimentological, and depositional characteristics of these conventional sources in the context of unconventional hydrocarbon exploration and is likely to form the foundation of an exciting new phase of exploration in the region.
Session 2: Existing Practices and Advances in Basin Modeling
With the recent upbeat in the E&P lifecycle and the challenges in finding giant fields, an aggressive exploration campaign has become a necessity to unlock any economically viable hydrocarbon. The prediction of a suitable petroleum system is an integral part of this campaign. A gradual shift from the conventional exploration approach to finding new hydrocarbon is increasingly becoming apparent. The Middle East boasts of multiple excellent source rocks that have contributed to mega-giant fields. These prolific organic-rich formations offer opportunities to develop unconventional plays as well. Notable hybrid systems are the Early Silurian (Qusaiba Member) and Middle-Late Jurassic (Tuwaiq Mountain, Hanifa, Jubaila and their equivalents) source rocks that contain adsorbed hydrocarbons while also charging conventional reservoirs. Improved digital capabilities have enabled a more integrated approach to basin characterization and newly available advanced data and technologies impact the capacity of basin modelling to reduce risk.
Interestingly, some of the organic-rich formations of the Middle East are very tight and may contain toxic compounds. To de-risk such plays, advanced basin modeling approaches use classical adsorption with lab-derived Langmuir parameters, but also compositional models including acid gases such as CO2 and H2S. The integration with petrophysics and geomechanics is becoming rapidly inevitable to unravel the complexities associated with unconventional resources. The use of petrophysical and geochemical data such as mineralogy, TOC content, kerogen volume, fluid typing, pore pressure, and permeability is imperative to understand the evolution and dynamics in 3D space.
The application of geomechanics is required to have any success in unconventional plays, especially in the Middle East, where complexities are associated with the predominant carbonate source rocks. Unconventional production relies on hydraulic fracturing, which cannot be optimally achieved without a proper understanding of the stress field hence, a 3D coupled geomechanical modelling is essential. Lastly, the incorporation of forward stratigraphic modelling of source rocks and organic matter is increasingly used to help to understand the heterogeneities associated with organic matter distribution prior to full 3D coupled basin model simulation.
This session welcomes the submission of unique case studies to discuss existing practices, and advances in basin and petroleum systems modelling that promote the integration of different disciplines to unlock unconventional plays in the Middle East region.
Session 3: Source Rocks Geochemistry
With increasing exploration and development of shale oil plays as compared to the more mature shale gas reservoirs, it has become critical to better understand thermal maturity differences, and variations in fluid types as a function of depositional environments, organic matter preservation or lack of it, and paleo heat flow patterns.
The basic component of a source rock is kerogen (preserved organic matter), which alters and matures to hydrocarbon after being exposed to continuous pressure and temperature. This maturation leads to the generation, expulsion, and migration of the hydrocarbon from the source rock to the reservoir rock. Poor or lack of migration can result in a significant accumulation of producible hydrocarbons within the source rock itself.
Proper characterization of a source rock petroleum system involves understanding both organic and inorganic geochemistry. The objective of this session is to delve into relevant technical information for comprehensive geochemical evaluation of Middle-Eastern source rocks. We invite knowledge sharing and case studies related to the following topics:
- Organic Petrology (maceral analyses, OM quality, vitrinite reflectance, maturity, etc)
- Organic matter maturation and alteration studies (kerogen typing and quality, transformation index, etc)
- Rock Eval and LECO Testing of core and cuttings samples for overall TOC content and maturity inference.
- Chemo-stratigraphy (inorganic geochemistry) for basin modeling (ICP , XRF, isotope analysis,etc).
- Gas and liquid chromatography of produced crude and oils extracted from core and cuttings samples.
- SARA and Biomarker analyses (fingerprinting) of produced crude and extracted oil from rock samples.
- Estimating API of produced crude, viscosity, GOR from geochemical analysis of rock samples.
- Inference of depositional environments and bio-facies from rock and oil geochemistry.
- Quality control and uncertainties in measurements associated with equipment, techniques, drilling mud contamination, Tmax-to-R0 correlations; etc.
Session 4: Source Rocks Geomechanics
Commercial development of unconventional reservoirs is only possible through the utilization of horizontal drilling and hydraulic fracturing practices. Both these technologies require proper understanding of the geomechanical properties and behavior of the target rocks as well as that of the overlying and underlying strata.
The complex depositional processes that produce source rocks result in multi-scale heterogeneities, which significantly influence the mechanical properties and behavior of such reservoirs when subjected to natural and induced stresses. Geomechanical properties of these systems are highly anisotropic in nature, and thus unconventional reservoirs are now more commonly modeled as transverse isotropic for practical applications.
Additionally, most unconventional resource systems are riddled with geological interfaces (slickensides, volcanic ash-beds, mudstone-carbonate boundaries, calcite veins, stylolites, etc), which influence hydraulic fracture propagation and closure. Most of these interfaces are not detectable by standard resolution logs, but are essential for proper modeling of the generated fracture geometries.
The focus of this session is to discuss the multidisciplinary role of geomechanics and its applications in successful development of unconventional reservoirs in the Middle East. Important learnings from worldwide source rocks are welcome but should be limited to strong analogs. Suggested topics are listed below:
- Structural and Tectonic influences on in-situ stress regimes.
- Relevance of pore pressure and poro-elasticity in mechanical behavior of ultra-tight, nano-pore dominated rocks
- Lab measurement of anisotropic mechanical properties (Young’s Moduli, Poisson’s Ratio, fracture toughness, biot coefficient, friction angle, cohesion, UCS, tensile strength, etc).
- Geo-mechanical property predictions based on logs and geophysical data.
- Geological Interfaces: identification, characterization, and applications in modeling
- Natural fractures: How much do they really matter?
- Wellbore Stability Modeling
- Hydraulic Fracture Modeling
- Fracture Diagnostic Techniques (DFIT, FIT, LOT)
- Casing deformation during completions and early production.
Session 5: Petrophysical Evaluation of Source Rocks
Organic shales are not only source rocks for conventional reservoirs, but they can become themselves producible reservoirs if the appropriate petrophysical and mechanical conditions are met. In unconventional reservoirs, there are two equally important aspects to evaluate: Reservoir Quality (RQ) and Completion Quality (CQ). RQ refers to the quality of the petrophysical properties required to make the reservoir suitable for commercial development. This includes the evaluation of mineralogy, porosity, TOC content, kerogen volume and maturity, hydrocarbon type, and saturation. Permeability, hydrocarbon producibility, and pore pressure are also important parameters, although they are more difficult to assess in source rocks. Evaluate properly RQ is critical in the early exploration and appraisal stages to assess the commercial viability of a play or a field. The CQ refers to how easy will be to hydraulically frac the rock, how the fracture propagates in the reservoir, and how the stimulation fluids will interact with the formation fluids and minerals. In the vertical pilot wells, the RQ and CQ evaluation helps to identify sweet spots, decide where to land the horizontals, and plan the well trajectory.
Typically, unconventional reservoirs are thoroughly evaluated in vertical pilot wells using extensive log suites, that in addition to basic tribble-combo logs, include advanced measurements such as gamma-ray spectroscopy, NMR, dielectric, full-waveform sonic, and borehole images. Log based model results are compared and calibrated to specialized core analysis. Lateral wells can be evaluated from a combination of logs and cuttings using advanced mud logging techniques.
This session will focus principally on petrophysics workflows and methods integrating logs, core analysis, cuttings analysis and mud logging to evaluate the reservoir quality. We will favor workflows, methodologies, and case studies developed or customized for the Middle East unconventional reservoirs. We can also accept case studies comparing Middle East source rocks to analog examples in other unconventional plays or showing techniques that can be applied or adapted to the middle eastern reservoirs.
Session 6: Unconventional Geophysics for Unconventional Plays
Over the last decades, the oil and gas industry has evolved delivering new technologies that have entirely changed business fundamentals. A significant change is in the perception of fine-grained, organic-rich rock treated as a source rock reservoir rather than part of a conventional petroleum system. The Middle East has a number of very tight organic-rich formations that offer a great opportunity to be developed as part of unconventional plays. The challenge remains in developing fit-for-purpose technologies, critical to understand reservoir complexities, increasing production, and maintaining costs and time efficiency.
Geophysical data play a critical role in unconventional developments as a unique tool that delineates properties away from the wellbore. 3D seismic imaging data contributes to the mapping of structural complexities and weakness zones in the subsurface allowing for robust closure stress prediction. Further, through AVO inversion, we are able to make predictions for elastic properties linking rock minerals, porosity, and fluid properties. Surface seismic can be complemented by micro-seismic acquired data to estimate the simulated rock volume and fine-tune operational parameters. Finally, full dynamic integration of AVO attributes derived from seismic with paleo-stresses and structural evolution and with drilling and fracking data provides a new avenue of data mining. Furthermore, additional work is needed to facilitate the integration of geophysical data with geo-mechanics and geo-modeling to optimize our operations and reduce exploration risks.
This session welcomes the submission of unique case studies highlighting new approaches and advancements in geophysical data conditioning/integration workflows that prompts multi-disciplinary methodologies to unlock unconventional plays in the Middle East.