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Petrophysics and Well Logs

Explorer Emphasis Article

New developments in digital rocks and digital outcrop models continue to put more data – and more realistic data – on geoscientists’ desktops.

American Association of Petroleum Geologists (AAPG)
Learn! Blog

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)
Workshop
Muscat, Oman
Monday, 6 April Wednesday, 8 April 2026, 8:00 a.m.–5:00 p.m.

The AAPG Structural Styles of the Middle East is back! This exciting and highly anticipated Geoscience Technology Workshop will take place from 6 – 8 April 2026, in Muscat, Oman. This workshop aims to explore the diverse structural styles resulting from the different deformation phases on the tectonostratigraphic framework of the Arabian Plate and adjacent regions.  

American Association of Petroleum Geologists (AAPG)
Field Seminar
Muscat, Oman
Sunday, 5 April 2026, 8:00 a.m.–4:30 p.m.

This one-day advanced course delivers a focused and highly practical framework for interpreting structural styles in the Middle East, combined with the unique advantage of applying Generative AI (GenAI) to elevate geological understanding and decision-making. Built for geoscientists working in exploration, development, or basin modeling, the course emphasizes practical techniques, hands-on interpretation, and modern tools that increase accuracy, speed, and confidence in structural workflows. We begin with a foundational module designed to unify all participants, regardless of background, around the principles of fault mechanics and structural style recognition. Participants will revisit faulting fundamentals, mechanical stratigraphy, and structural style classification. The goal is to align interpretation techniques with geological processes, and to establish a shared vocabulary for the day. An introduction to GenAI highlights its role in managing structural ambiguity and enhancing workflows, helping geoscientists clarify options when data is incomplete or conflicting. Normal Faulting Through a sequence of focused exercises, participants explore fault segmentation, growth history, and interpretation in extensional domains. This segment reinforces practical skills in identifying and validating fault geometries in map and section views. GenAI is introduced as a scenario-building tool: participants will use it to explore structural uncertainty, generate alternative models, and compare extensional interpretations, all using fragmented or incomplete datasets, not as a seismic interpreter but as a powerful thought partner. Strike-Slip and Transtension This module targets the complexity of strike-slip and transtensional systems. Participants learn to distinguish pure strike-slip geometries from transtensional overprints, assess compartmentalization, and model realistic deformation patterns. Interpretation exercises develop structural reasoning in map and cross-sectional views. GenAI is applied here to integrate multi-source inputs, such as field data, analogs, and internal reports, to support rapid synthesis and generate testable structural concepts. Salt Tectonics The final segment introduces key diagnostic features of salt-related deformation: welds, reactive and passive diapirs, and halokinetic sequences. Exercises train participants to recognize salt-influenced geometries and link them to broader structural evolution. GenAI then supports pattern recognition and memory mining, leveraging archived knowledge from prior studies, case histories, and analog reports to help geoscientists build and validate interpretations faster and with more confidence. What makes this course different? This is not a theoretical seminar. It’s a learning accelerator, where foundational concepts are applied in realistic interpretation settings, then extended with state-of-the-art GenAI capabilities. You’ll not only sharpen your structural reasoning, but learn how to delegate time-consuming tasks, like synthesizing legacy reports, generating alternative scenarios, or exploring interpretation options, to an intelligent AI partner. By the end of the day, participants will: Recognize and differentiate key fault styles with confidence Improve fault interpretation quality and geological risk assessment Use GenAI to test structural scenarios and extract insight from fragmented or incomplete datasets Accelerate their ability to interpret, communicate, and make decisions in structurally complex plays This course equips you with what matters most today: deep geological understanding, elevated by the best of modern AI. Who Should Attend and Why This course is ideal for both new hires and experienced geoscientists working across exploration, development, and reservoir modeling. Its exercise-driven format ensures that participants with diverse backgrounds, geologists, geophysicists, geomodelers, can engage, learn, and apply. While some familiarity with geosciences is beneficial, prior structural geology training is not required. What makes this course indispensable is its ability to bridge theory and practice: participants will gain a clear understanding of how rocks deform over time, how fault geometries evolve, and how these structures influence seismic interpretation, mapping, and static/dynamic modeling. By integrating real case studies and GenAI-enhanced workflows, the course delivers practical tools to improve subsurface outcomes and build models that match project maturity and business objectives. Main Objective This course delivers the structural geology foundations every geoscientist needs to confidently interpret faults and build or validate static models. Derived from decades of project reviews, interpretation support, and applied field experience, these “must-know” concepts include fault mechanics, growth, segmentation, and structural style recognition, relevant to both exploration and production settings. Participants will strengthen their ability to recognize deformation styles, interpret fault geometries in map and section view, assess mechanical stratigraphy and reactivation risk, and QC interpretations with confidence. Throughout the course, GenAI is introduced not as a software tool, but as a workflow enhancer, used to reduce ambiguity, test structural hypotheses, and extract insight from fragmented datasets or legacy documentation. This empowers geoscientists to think more clearly, work more efficiently, and improve the geological soundness of their models. Key Points Date: 5th April,2026 Venue: Crowne Plaza Hotel, OCEC Registration Fee: $590 Registration Deadline: 22nd February,2026 *Registration will be opening shortly Instructors Pascal Richard PRgeology Jan Witte Falcon-Geoconsulting

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American Association of Petroleum Geologists (AAPG)
Field Seminar
Muscat, Oman
Thursday, 9 April Friday, 10 April 2026, 7:30 a.m.–7:00 p.m.

The Jabal Akhdar in the Central Oman Mountains forms a ~90 km × 60 km dome. The core of this dome consists of Cryogenian to Ediacaran siliciclastics and carbonates, including source rocks. These rocks are separated from the overlying rocks by a spectacularly exposed angular unconformity. The rocks above this unconformity are Permo-Mesozoic shelf carbonates of the Arabian passive margin. The rocks below the unconformity are folded twice, while those above show no such folding. During the Late Cretaceous, Arabia was overthrust by the Samail Ophiolite and Hawasina deep-sea sedimentary rocks. Final doming occurred during the late Eocene to early Miocene. The Jabal Akhdar Dome is a textbook example of stratigraphy and structural geology development from the Cryogenian to the present. Furthermore, findings from the dome can be used as a natural laboratory and serve as an analogue for the hydrocarbon-bearing sequences in interior Oman. The two-day field trip will start at the Saiq Plateau where we will examine Cryogenian Snowball-Earth diamictites with cap carbonates, blended within the scenic landscape of Jabal Akhdar. The second day will start at a breath-taking vista point at Wadi Bani Awf. From there we will descend into the core of the Jabal Akhdar and explore the structural style of the Cryogenian and younger succession. Field Trip Information: Date: 9th – 10th April 2026 Time: 7:30am – 7pm Field Trip fee: $550 Registration Deadline: 5th March 2026 (*registration will be opening shortly) Fees Include: 1 night accommodation in a hotel Guided hiking tour through rose farms and ancient villages in Jebel Akhdar (2–3 hours) Traditional Omani lunch hosted at a local home BBQ dinner in a scenic open area at Jebel Akhdar All transportation (4x4s) Field Trip Leaders Ivan Callegari GUtech Oman Wilfried Bauer GUtech Oman Andreas Scharf Sultan Qaboos University

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American Association of Petroleum Geologists (AAPG)
Online e-Symposium
Thursday, 10 May 2012, 12:00 a.m.–12:00 a.m.

Recognition and Correlation of the Eagle Ford, Austin Formations in South Texas can be enhanced with High Resolution Biostratigraphy, fossil abundance peaks and Maximum Flooding Surfaces correlated to Upper Cretaceous sequence stratigraphic cycle chart after Gradstein, 2010.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 2 July 2020, 4:00 p.m.–5:00 p.m.

Presented by Kevin C. Hill, Associate Professor, University of Melbourne Gravity modelling of Australia's southern margin reveals that the initial rift with Antarctica was beneath the current Ceduna Delta. A regional, high-quality seismic traverse from the coast to oceanic crust across the Bight Basin has been assembled and interpreted in detail, then balanced, restored, decompacted, and replaced at paleo-water depths. The Late Cretaceous Ceduna Delta developed above a Late Jurassic-Early Cretaceous rift basin in three stages punctuated by significant pulses of uplift and erosion across areas >100 km wide and with up to 1 km of erosion. The Cenomanian White Pointer delta prograded into deepening water and hence underwent gravitational collapse. This was terminated in the Santonian when the Antarctic margin was pulled out from below, thus supplying heat to a remnant thicker outer margin crust, causing doming and erosion. Importantly, this established the saucer-shaped geometry of the Ceduna Delta that persisted throughout its development, so that any hydrocarbons generated in the southern half of the basin would have migrated towards this outer margin high. The Tiger Formation was deposited in shallow water in a full rift basin prior to breakup, which was followed by regional thermal subsidence. The Hammerhead delta developed on the newly formed passive margin but was terminated by another pulse of uplift and erosion, perhaps associated with a change in plate motion at the end of the Cretaceous. The finite element modelling of this proposed tectonic evolution will test its validity and predict hydrocarbon generation and migration through time.

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American Association of Petroleum Geologists (AAPG)
Online e-Symposium
Thursday, 2 October 2014, 2:00 p.m.–3:00 p.m.

This course is ideal for individuals involved in Midland Basin exploration and development. Successful development of Wolfcamp shale oil relies on complex inter-relationships (ultimately interdependencies) within and between a wide variety of scientific disciplines, financial entities, and company partnerships. 

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Wednesday, 15 July 2020, 12:00 p.m.–1:00 p.m.

On July 15th, Raffaele Di Cuia and other members ouf the committee for our upcoming Workshop 'Structural Styles and Hydrocarbon Prospectivity in Fold Thrust Belt Settings: A Global Perspective' will be joining the Let's Connect webinar. The call for abstracts for this workshop, to be held in November in Barcelona is open until July 30th. Join this webinar and learn more about how to tackle the issues of Thrust Belt Settings! Register for the webinar and learn more about the face to face GTW!

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American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Wednesday, 20 May 2020, 7:00 p.m.–8:30 p.m.

Join us for 'Matching Capabilities and Capacity With Current and Emerging Demand Areas; Building a Business Plan That Reflects the Realities of Opportunities'. Webinar will be presented via Zoom 7pm - 8:30pm CDT, 20 May 2020. During this webinar we will discuss: Matching technologies and companies Keys to Building a Resilient Early-Stage Business Multi-Industry Technology: Robotics as a Service

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)
Online e-Symposium
Thursday, 8 December 2011, 12:00 a.m.–12:00 a.m.

This e-symposium focuses on methods for predicting connectivity within clastic fluvial systems.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 27 August 2020, 3:00 p.m.–4:00 p.m.

There are over 300 known active onshore mud volcanoes globally, and many more offshore. Mud volcanoes are subsurface fluid escape features in which high pore pressures drive fluids, gases, and subsurface sediments to the surface. This talk will summarize mud volcanoes around the world and examine mud volcano plumbing systems and their link to petroleum systems.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 28 October 2021, 10:00 a.m.–11:00 p.m.

As an industry we’re constantly challenged to improve our business on a worldwide stage. How do we continue improving the safe delivery of high quality, economical wells and production where understanding of social requirements and the license to operate are rapidly changing? Join us for a conversation with a panel of drilling engineers to gain insight to their understanding of how we can meet these challenges and impact well delivery planning processes and outcomes - from clarity on deliverables, process improvements, advances in technology, to building better business models for modern decision making.

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American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 21 May 2020, 9:00 p.m.–10:00 p.m.

Henry W. Posamentier discusses the application of 3-D seismic stratigraphic analyses to the mitigation of risk associated with lithology prediction prior to drilling – workflows and techniques. Principles and workflows of seismic stratigraphy and seismic geomorphology will be discussed and numerous examples will be shown from a variety of different depositional settings.

American Association of Petroleum Geologists (AAPG)
DL Abstract

As oil and gas exploration and production occur in deeper basins and more complex geologic settings, accurate characterization and modeling of reservoirs to improve estimated ultimate recovery (EUR) prediction, optimize well placement and maximize recovery become paramount. Existing technologies for reservoir characterization and modeling have proven inadequate for delivering detailed 3D predictions of reservoir architecture, connectivity and rock quality at scales that impact subsurface flow patterns and reservoir performance. Because of the gap between the geophysical and geologic data available (seismic, well logs, cores) and the data needed to model rock heterogeneities at the reservoir scale, constraints from external analog systems are needed. Existing stratigraphic concepts and deposition models are mostly empirical and seldom provide quantitative constraints on fine-scale reservoir heterogeneity. Current reservoir modeling tools are challenged to accurately replicate complex, nonstationary, rock heterogeneity patterns that control connectivity, such as shale layers that serve as flow baffles and barriers.

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Request a visit from Tao Sun!

American Association of Petroleum Geologists (AAPG)
DL Abstract

For well over a century there have been conflicting indications of the strength of the crust and of faults and what controls them.  Much of our ignorance comes quite naturally from the general inaccessibility of the crust to measurement--in contrast with our understanding of the atmosphere, which is much more accessible to observation as well as more rapidly changing.  Crustal strength is best understood in deforming sedimentary basins where the petroleum industry has made great contributions, particularly in deforming petroleum basins because of the practical need to predict. In this talk we take a broad look at key issues in crustal strength and deformation and what we can learn from boreholes, earthquakes, active fault systems, and toy models.

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Request a visit from John Suppe!

American Association of Petroleum Geologists (AAPG)
DL Abstract

The Energy sector is a changing business environment. Throughout the 20th century fluctuations of oil supply and demand produced changes in the barrel price that pushed the growth or shrinkage of the industry. In this 21st century, new challenges such as diversification of the energy mix, boosting gas demand, require the exploration of critical minerals and development of new technologies as well.

Request a visit from Fernanda Raggio!

American Association of Petroleum Geologists (AAPG)
DL Abstract

Paleozoic North America has experienced multiple mountain building events, from Ordovician to Permian, on all margins of the continent. These have had a profound effect on the resulting complex basins and their associated petroleum systems. Subsequent uplift, erosion and overprinting of these ancient systems impedes the direct observation of their tectonic history. However, the basin sedimentary records are more complete, and provide additional insights into the timing and style of the mountain building events. In this study, we employ ~90 1D basin models, ~30 inverse flexural models, isopachs, and paleogeographic maps to better understand the Paleozoic history of North America.

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Request a visit from Kurt W. Rudolph!

American Association of Petroleum Geologists (AAPG)
DL Abstract

While there are many habitats that are associated with the deposition of organic-rich marine and lacustrine source rocks, one important pathway is linked to the onset of increased basin subsidence associated with major tectonic events. A key aspect is that this subsidence is spatially variable, with the uplift of basin flanks contemporaneous with the foundering of the basin center, resulting in a steeper basin profile.

Request a visit from Kurt W. Rudolph!

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)
DL Abstract

Around 170 million years ago, the Gulf of Mexico basin flooded catastrophically, and the pre-existing landscape, which had been a very rugged, arid, semi-desert world, was drowned beneath an inland sea of salt water. The drowned landscape was then buried under kilometers of salt, perfectly preserving the older topography. Now, with high-quality 3D seismic data, the salt appears as a transparent layer, and the details of the drowned world can be seen in exquisite detail, providing a unique snapshot of the world on the eve of the flooding event. We can map out hills and valleys, and a system of river gullies and a large, meandering river system. These rivers in turn fed into a deep central lake, whose surface was about 750m below global sea level. This new knowledge also reveals how the Louann Salt was deposited. In contrast to published models, the salt was deposited in a deep water, hypersaline sea. We can estimate the rate of deposition, and it was very fast; we believe that the entire thickness of several kilometers of salt was laid down in a few tens of thousands of years, making it possibly the fastest sustained deposition seen so far in the geological record.

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Request a visit from Frank Peel!

American Association of Petroleum Geologists (AAPG)
DL Abstract

Subsurface risk and uncertainty are recognized as very important considerations in petroleum geoscience. And even when volume estimates are relatively accurate, the reservoir characteristics that determine well placement and performance can remain highly uncertain. In analyzing results and work practices, three aspects of uncertainty are reviewed here.

Request a visit from Kurt W. Rudolph!

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)
DL Abstract

President Biden has laid out a bold and ambitious goal of achieving net-zero carbon emissions in the United States by 2050.  The pathway to that target includes cutting total greenhouse gas emissions in half by 2030 and eliminating them entirely from the nation’s electricity sector by 2035. The Office of Fossil Energy and Carbon Management will play an important role in the transition to net-zero carbon emissions by reducing the environmental impacts of fossil energy production and use – and helping decarbonize other hard-to abate sectors.

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Request a visit from Jennifer Wilcox!

American Association of Petroleum Geologists (AAPG)

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