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Petrophysics and Well Logs

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This workshop will bring the attendees up to date with the latest academic and case-studies from the field of advanced surface logging technologies.

American Association of Petroleum Geologists (AAPG)
Explorer Emphasis Article

Over the last decade or so, marine controlled source electromagnetic (CSEM) technology has proven to be an effective tool to de-risk deepwater, really high cost drilling decisions. Yet it, along with magnetotellurics technology (MT), has both good days and bad days in the continuing uncertain financial environment.

American Association of Petroleum Geologists (AAPG)
Explorer Emphasis Article

It’s widely known that refracturing a horizontal well can help to reduce the interaction between so-called parent and child wells by causing a high stress area around the refractured wells and diverting child well fractures away from the parent well.

American Association of Petroleum Geologists (AAPG)
Explorer Historical Highlights

The present day Cretaceous Codell oil and gas development in the central portion of the Denver Basin of Colorado can be attributed to an earlier effort in bringing the Codell to the attention of the industry.

American Association of Petroleum Geologists (AAPG)
Explorer Article

For anyone interested in the methods of observing and quantifying the pore systems that control hydrocarbon and flow in unconventional reservoirs, AAPG’s new volume is what you’ve been waiting for. AAPG recently released Memoir 112: “Imaging Unconventional Reservoir Pore Systems.”

American Association of Petroleum Geologists (AAPG)
Explorer Emphasis Article

The Next 100 Years: Data management is a crucial component of oil exploration. What does the century ahead look like for Big Data in the oil field?

American Association of Petroleum Geologists (AAPG)
Middle East Blog

The GEO 2018 committee welcomes your abstracts for oral and poster presentations at the 13th Middle Geosciences Conference and Exhibition (GEO 2018) which will take place from 5 — 8 March in Bahrain. Submit today and join the largest gathering of geoscience professionals in the Middle East.

American Association of Petroleum Geologists (AAPG)
Explorer Article

TIGs and SIGs are designed to encourage greater Member participation in specific topics or interests – and to enhance Member engagement with other Members, and with AAPG. But what is the current roster of TIGs and SIGs – and who do you contact to join their fun?

American Association of Petroleum Geologists (AAPG)
Search and Discovery Article

Relative permeability in shales is an important petrophysical parameter for purposes of accurate estimation of production rate and recovery factor, efficient secondary recovery, and effective water management. We present a method to estimate saturation-dependent relative permeability in shales based on the interpretation of the low-pressure nitrogen adsorption-desorption isotherm measurements. Relative permeability were determined for 30 samples from the gas — and oil — window of Eagle Ford and Wolfcamp shale formations. These sample have low-pressure helium porosity (LPHP) in the range of 0.04 to 0.09 and total organic content (TOC) in the range of 0.02 to 0.06. The samples were ashed to study the effects of removal of organic matter on the pore size distribution, pore connectivity, and relative permeability. The estimated irreducible water saturation and residual hydrocarbon saturation are directly proportional to the TOC and LPHP, and exhibit 15% variation over the entire range. Pore connectivity, in terms of average coordination number, decreases by 33% with the increase in TOC from 0.02 to 0.06. The estimated fractal dimension is close to 2.7 for all the samples. The estimated relative permeability of aqueous phase and that of hydrocarbon phase at a given saturation is inversely proportional to the TOC. Relative permeability curves of the hydrocarbon phase for geological samples from various depths in a 100-feet interval indicate that the hydrocarbon production rate will vary drastically over the entire interval and these variations will increase as the hydrocarbon saturations reduce in the formation. In contrast, relative permeability curves of the aqueous phase suggest limited variation in water production rate over the entire interval. Further, based on the relative permeability curves, the hydrocarbon production is predicted to be negligible for hydrocarbon saturations below 50% and the water production is expected to be negligible for water saturations below than 80%. Efforts are ongoing to use the laboratory-based estimates to predict field-scale production and recovery rates.

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American Association of Petroleum Geologists (AAPG)
Search and Discovery Article

Measurements of fluid wetting characteristic are made routinely on rock samples. However, there are no published petrophysical models to differentiate between oil-wet and water-wet fractions of a reservoir sequence using commonly available log suites. This presentation builds on our previous publication that describes the unconventional reservoir petrophysical model we have developed (Holmes, 2014). Essentially, we define four porosity components, namely total organic carbon, clay porosity, effective porosity, and “free shale porosity.” This last component is an indirect calculation if the first three components do not sum to total porosity.  Porosity/resistivity plots can be constructed for the total porosity and interpreted in a standard fashion. These will mostly indicate a water-wet system where the effective porosity fraction is examined. A second porosity/resistivity plot compares resistivity with “free shale porosity,” and is clearly interpreted to indicate Archie saturation exponents of much larger than 2 — frequently in excess of 3 — indicating the oil-wet fraction of the reservoir system. Additionally, the plots suggest low to very low values of cementation exponent, ranging from 1.0 to 1.5.   Examples from the Bakken of Montana and North Dakota, the Niobrara of Colorado, and the Wolfcamp and Spraberry of Texas are presented showing quantitative distinction of water-wet vs. oil-wet reservoir components.

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American Association of Petroleum Geologists (AAPG)
Short Course
Sunday, 25 September 2022, 8:30 a.m.–9:30 a.m.

Date: 25 September 2022 Time: 8:30am - 4:30pm Course Instructor: Alberto Ortiz, Net Zero Carbon Solutions Registration Fee: $530 Registration Deadline: 25 August 2022 Short Course registration is included as part of the GTW registration process. The petrophysical characterization of unconventional shale-type reservoirs has been one of the most approached and relevant issues in the oil and gas industry in the last 8 years. This is because after several years, the operating companies comprehended the impact that an appropriate characterization of the reservoir has on their project economics. Another reason for this were the technical obstacles encountered in the measurement of petrophysical properties such as porosity, saturation and permeability due to the complexity of this type of reservoir. Obstacles and limitations not only relate to laboratory measurements but also to electrical logging tools. As a consequence of this, nowadays, petrophysical evaluations in this type of reservoir do not have standardized workflows established and accepted worldwide as is the case for conventional reservoirs. This motivates the professionals involved in the study of this type of rocks to dedicate a lot of effort in the validation of the technologies used, and sometimes it is difficult for them to understand the results, the evaluation of uncertainties and the construction of petrophysical models with results and representative parameters of the subsurface conditions. This course will focus on providing key knowledge for a better characterization of the rock both in the aspects related to the matrix represented by mineralogy and kerogen as well as the fluids present. The approach will be based on the convergence of different technologies that support and give robustness to the results. The contents that will be provided will include laboratory testing techniques and petrophysical evaluation of electrical well logs for unconventional shale-type reservoirs. The contents provided will cover a variety of studies based on the most diverse physical principles that will include the latest advances and techniques used in the industry such as Nuclear Magnetic Resonance, Spectroscopy, Dielectric, Computed axial tomography and SEM images, among others. As a result of this, attendees will have tools that allow a more comprehensive understanding of this type of rocks, a better assessment of the uncertainty of the model used and the necessary steps to improve its precision, accelerating the learning curve. The contents provided will also allow knowing the critical parameters that must be taken into account for the definition of areas to be drilled. Course Topics Reservoir heterogeneity characterization from outcrops to lab data and electrical logging. Most relevant unconventional plays of the world. Main characteristics. The petrophysical model. Components and definitions, construction, uncertainties, strengths and weakness. Lab studies: porosity, saturation, mineralogy, organic geochemistry and permeability. Electrical logging response on unconventional shale plays: triple combo, NMR, NMR T1T2, nuclear spectroscopy, spectral GR, dielectric. The effect of maturity on kerogen. Challenges on water saturation calculation. Data integration. Interpretation workflows and core calibration.

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American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Wednesday, 9 June 2021, 7:00 p.m.–8:30 p.m.

Join us for 'Pivoting 2021: The New Way to Work'. Panelists will discuss the way that work is done, both in operations and support roles, and discuss specific examples of technologies being used, and how they contribute to a safer, more efficient and profitable endeavor. Webinar will be presented via Zoom 7pm - 8:30pm CDT, 9 June 2021.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 1 October 2020, 11:00 a.m.–12:00 p.m.

Join AAPG Asia Pacific to hear Agus Ramdahn, PhD to hear about a method of combining Bowers Method with density-sonic cross plots to estimate overpressure in the shelfal area of the Lower Kutai Basin This webinar will be presented via Zoom on Thursday 1 October at 11:00 Singapore Time

American Association of Petroleum Geologists (AAPG)
Online e-Symposium
Thursday, 21 January 2016, 2:00 p.m.–3:00 p.m.

An overview of a new ambient seismic imaging method and applications of the method throughout the lifecycles (exploration through refracing) of unconventional oil and/or gas fields.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 3 December 2020, 11:00 a.m.–12:00 p.m.

Patawarta Diapir, approximately 2-6km2 located in the Central Flinders Ranges, South Australia, has been interpreted as a single allochthonous salt sheet containing Tonian-aged igneous and layered evaporite sedimentary intrasalt inclusions derived from the Callanna Group. In this webinar, Rachelle Kernen describes the diapir as five primarily silty limestone inclusions (0.5-2km2), re-interpreted as Ediacaran-aged Wonoka Formation and Patsy Hill member of the Bonney Sandstone (Wilpena Group). Webinar presented Thursday 3 December 2020 at 11:00 SGT (GMT+8) Singapore time

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American Association of Petroleum Geologists (AAPG)
Online e-Symposium
Wednesday, 5 March 2014, 12:00 a.m.–12:00 a.m.

Explore three of the great wonders of the geological world. Take a guided tour of classic geological sites on the Colorado Plateau.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Wednesday, 3 June 2020, 7:00 p.m.–8:30 p.m.

Join us for 'Analytics-Based Opportunities in Double Black Swan Times' where we will discuss the steps companies are taking, business considerations in cross-industry analytics -start-ups to majors, analytics agility in a double black swan world, enabling the workforce to utilize and exploit data remotely using the cloud and machine learning. Webinar will be presented via Zoom 7pm - 8:30pm CDT, 3 June 2020.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 8 October 2020, 3:00 p.m.–4:00 p.m.

Join us as Doug Peacock discusses how changes in oil price impact reserves in theory, and with practical industry examples. Presentation will be via Zoom on Thursday 8 October 15:00 SGT (UTC+8) Singapore time zone

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Tuesday, 5 May 2020, 12:00 p.m.–1:00 p.m.

Sequence stratigraphy is a method for stratigraphic interpretation, pioneered by Vail and colleagues in the mid 70’s, which explains the complex geometries that sediments create as they fill accommodation in response to changes in rates of sedimentation, subsidence, uplift and eustasy. This method was developed based on observations and concepts developed as early as in the 1800’s. Based on this strong scientific foundation, pioneer work from Caster, Sloss, Wheeler, Campbell, and Asquith established the basis for the methodology. These researchers established a new way to correlate stratigraphic units, demonstrating the time-transgressive nature of lithostratigraphic formations.

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American Association of Petroleum Geologists (AAPG)
American Association of Petroleum Geologists (AAPG)
Online e-Symposium
Tuesday, 16 April 2013, 12:00 a.m.–12:00 a.m.

The goal of this e-symposium is to provide an overview of the latest trends and technologies for water management for oil and gas drilling, completions, and production.

American Association of Petroleum Geologists (AAPG)
VG Abstract

In comparison with the known boundary conditions that promote salt deformation and flow in sedimentary basins, the processes involved with the mobilization of clay-rich detrital sediments are far less well established. This talk will use seismic examples in different tectonic settings to document the variety of shale geometries that can be formed under brittle and ductile deformations.

Request a visit from Juan I. Soto!

American Association of Petroleum Geologists (AAPG)
VG Abstract

This is a less-technical education topic. It can be condensed to an hour or given as 2 two-hour sessions. It stresses selected controversial aspects of fracking that touch some combination of environment and economics and includes a short video of how fracking is done.

Request a visit from David Weinberg!

American Association of Petroleum Geologists (AAPG)
VG Abstract

The following short course option was developed for geology and geophysics students that have not had much exposure to how geoscience is applied in industry. It can be tailored for undergraduate juniors and seniors or graduate students. The agenda can be modified to meet specific needs and time constraints. Contact the presenter to discuss options.

Request a visit from Fred Schroeder!

American Association of Petroleum Geologists (AAPG)
VG Abstract

The carbonate sequences that were deposited in the now exhumed Tethyan Ocean influence many aspects of our lives today, either by supplying the energy that warms our homes and the fuel that powers our cars or providing the stunning landscapes for both winter and summer vacations. They also represent some of the most intensely studied rock formations in the world and have provided geoscientists with a fascinating insight into the turbulent nature of 250 Million years of Earth’s history. By combining studies from the full range of geoscience disciplines this presentation will trace the development of these carbonate sequences from their initial formation on the margins of large ancient continental masses to their present day locations in and around the Greater Mediterranean and Near East region. The first order control on growth patterns and carbonate platform development by the regional plate-tectonic setting, underlying basin architecture and fluctuations in sea level will be illustrated. The organisms that contribute to sequence development will be revealed to be treasure troves of forensic information. Finally, these rock sequences will be shown to contain all the ingredients necessary to form and retain hydrocarbons and the manner in which major post-depositional tectonic events led to the formation of some of the largest hydrocarbon accumulations in the world will be demonstrated.

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Request a visit from Keith Gerdes!

American Association of Petroleum Geologists (AAPG)
VG Abstract

The Betic hinterland, in the westernmost Mediterranean, constitutes a unique example of a stack of metamorphic units. Using a three-dimensional model for the crustal structure of the Betics-Rif area this talk will address the role of crustal flow simultaneously to upper-crustal low-angle faulting in the origin and evolution of the topography.

Request a visit from Juan I. Soto!

American Association of Petroleum Geologists (AAPG)
VG Abstract

This lecture will discuss the differences between carbonates and siliciclastics from their chemical composition through their distributions in time and space. Building on these fundamental differences, we will explore the challenges carbonates pose to petroleum geologists in terms of seismic interpretation, reservoir quality prediction, field development, etc. Peppered with humorous personal stories, still raging academic debates, and the heartfelt frustrations of real industry professionals, the aim is to inspire students and young professionals to rise to the occasion and embrace the reservoir rocks that petroleum geologists love to hate.

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Request a visit from Noelle Joy Purcell!

American Association of Petroleum Geologists (AAPG)
VG Abstract

The following short course option was developed for geology and geophysics students that have not had much exposure to how geoscience is applied in industry. It can be tailored for undergraduate juniors and seniors or graduate students. The agenda can be modified to meet specific needs and time constraints.

Request a visit from Fred Schroeder!

American Association of Petroleum Geologists (AAPG)
VG Abstract

Analysis of microseismicity induced by hydraulic fracture stimulation in the Marcellus Shale shows changes in stress state for different zones of failure. During the treatment, shear failure occurs on both the J1 and J2 fracture orientations in response to different maximum stress orientations, indicating localized changes in the orientation during the treatment. Reactivation of a fault near the wellbore is associated with failure mechanisms with a higher volumetric component, indicating possible inflation of faults and fractures by the introduction of the slurry. Quantification of the stress conditions that are associated with inflation could potentially be used to optimize the stimulation by identifying which fractures will preferentially take on slurry volume.

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Request a visit from Sherilyn Williams-Stroud!

American Association of Petroleum Geologists (AAPG)
VG Abstract

Production from unconventional petroleum reservoirs includes petroleum from shale, coal, tight-sand and oil-sand. These reservoirs contain enormous quantities of oil and natural gas but pose a technology challenge to both geoscientists and engineers to produce economically on a commercial scale. These reservoirs store large volumes and are widely distributed at different stratigraphic levels and basin types, offering long-term potential for energy supply. Most of these reservoirs are low permeability and porosity that need enhancement with hydraulic fracture stimulation to maximize fluid drainage. Production from these reservoirs is increasing with continued advancement in geological characterization techniques and technology for well drilling, logging, and completion with drainage enhancement. Currently, Australia, Argentina, Canada, Egypt, USA, and Venezuela are producing natural gas from low permeability reservoirs: tight-sand, shale, and coal (CBM). Canada, Russia, USA, and Venezuela are producing heavy oil from oilsand. USA is leading the development of techniques for exploring, and technology for exploiting unconventional gas resources, which can help to develop potential gas-bearing shales of Thailand. The main focus is on source-reservoir-seal shale petroleum plays. In these tight rocks petroleum resides in the micro-pores as well as adsorbed on and in the organics. Shale has very low matrix permeability (nano-darcies) and has highly layered formations with differences in vertical and horizontal properties, vertically non-homogeneous and horizontally anisotropic with complicate natural fractures. Understanding the rocks is critical in selecting fluid drainage enhancement mechanisms; rock properties such as where shale is clay or silica rich, clay types and maturation , kerogen type and maturation, permeability, porosity, and saturation. Most of these plays require horizontal development with large numbers of wells that require an understanding of formation structure, setting and reservoir character and its lateral extension. The quality of shale-gas resources depend on thickness of net pay (>100 m), adequate porosity (>2%), high reservoir pressure (ideally overpressure), high thermal maturity (>1.5% Ro), high organic richness (>2% TOC), low in clay (<50%), high in brittle minerals (quartz, carbonates, feldspars), and favourable in-situ stress. During the past decade, unconventional shale and tight-sand gas plays have become an important supply of natural gas in the US, and now in shale oil as well. As a consequence, interest to assess and explore these plays is rapidly spreading worldwide. The high production potential of shale petroleum resources has contributed to a comparably favourable outlook for increased future petroleum supplies globally. Application of 2D and 3D seismic for defining reservoirs and micro seismic for monitoring fracturing, measuring rock properties downhole (borehole imaging) and in laboratory (mineralogy, porosity, permeability), horizontal drilling (downhole GPS), and hydraulic fracture stimulation (cross-linked gel, slick-water, nitrogen or nitrogen foam) is key in improving production from these huge resources with low productivity factors.

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Request a visit from Ameed Ghori!

American Association of Petroleum Geologists (AAPG)
VG Abstract

Hydraulic fracturing has been around for decades. This talk describes some of the first applications of the technology, how it developed over time, and our current understanding of its impacts with some discussion of both water and earthquake hazards.

Request a visit from Sherilyn Williams-Stroud!

American Association of Petroleum Geologists (AAPG)

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