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Petrophysics and Well Logs

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)
Explorer Article

The forum will include presentations given by leading experts from companies who have been successfully operating in the basin.

American Association of Petroleum Geologists (AAPG)
Explorer Article

Thanks to advancements in data management and seismic sensing, geophysical modeling has become indispensable in the search for oil. What will it become in the century ahead?

American Association of Petroleum Geologists (AAPG)
PSGD Blog

The AAPG Petroleum Structure and Geomechanics Division (PSGD) has announced the 2016 Best Paper Awards at the Annual Convention and Exhibition in Calgary, Alberta, Canada. Congratulations to Richard H Groshong, Jr., awarded 'Best Seminal Publication' for '3-D Structural Geology: A Practical Guide to Quantitative Surface and Subsurface Map Interpretation 2nd Edition'. We thank everyone for nominating the candidates. We also thank Bob Krantz, Bob Hatcher, and Gary Couples for their diligent work on the PSGD Best Paper Committee.

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American Association of Petroleum Geologists (AAPG)
Learn! Blog

Optimizing reservoirs and developing an ever-evolving intelligent model of a reservoir are key concerns for operators, particularly in challenging times. For that reason, they must have good production geologists on hand. A production geologist bridges a number of disciplines, most notably geology and engineering, but also geochemistry, geophysics, and numerical methods. Welcome to an interview with Terngu Utim who discusses production geology, its new potential and opportunities.

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American Association of Petroleum Geologists (AAPG)
Learn! Blog

The dynamics of fluid behavior and structural movement on the nano-scale can be complicated and not always what was expected. New research that analyzes the well information and cores using new techniques and technologies is yielding important and useful results. Welcome to an interview with Wen Zhou, Chengdu University of Technology, who discusses recent research findings.

American Association of Petroleum Geologists (AAPG)
Learn! Blog

Primary research in hydrocarbon generation is yielding new insights into the natural gas geochemical characteristics of conventional and unconventional reservoirs, along with discoveries relating to the geomechanical processes. Welcome to an interview with Chenglin Liu, China University of Petroleum-Beijing, who discusses enlightening new findings regarding the relationship between salinity and hydrocarbon geochemical characteristics.

American Association of Petroleum Geologists (AAPG)
Explorer Emphasis Article

Understanding the complex makeup of reservoirs is essential, and it requires considerable evaluation and time.

American Association of Petroleum Geologists (AAPG)
Learn! Blog

How does diagenesis affect rock physics? What is the relationship of the burial history to the rock physics? Both have a dramatic impact on the rock physics properties of not only the reservoir, but also the source and seals. Welcome to an interview with Per Avseth, who discusses rock physics and quantitative seismic interpretation. He also talks with us about how developing an effective rock physics model requires the integration of geological, geophysical, geochemical, and petrophysical information.

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American Association of Petroleum Geologists (AAPG)
Learn! Blog

You may not be aware that there was a super-Greenhouse environment during the Cretaceous, and that there were super-storms associated with it, and that analyzing the sediments deposited during that time can provide insight into the potential warming of climates, and also the cross-shelf transport of sediments. That is just one of many fascinating new areas of research that looks at data through new lenses, and with new analytical techniques. Welcome to an interview with Lesli J. Wood, Weimer Distinguished Chair and Professor in Sedimentary and Petroleum Geology, Colorado School of Mines.

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American Association of Petroleum Geologists (AAPG)
Field Seminar
Palermo, Italy
Thursday, 25 April 2024, 8:00 a.m.–9:00 a.m.

This one-day field trip will provide an introduction to a Miocene-Pliocene succession of southern Sicily, which includes outcrops of the Messinian Salinity Crisis (MSC), as well as the Messinian-Zanclean GSSP (Global Boundary Stratotype Sections and Point) and Zanclean stratotype. The MSC sedimentary record consists of an evaporitic-carbonate unit at the base (the Basal Limestone), overlain the Lower Gypsum unit, in turn overlain by the Upper Gypsum unit, and sealed by transgressive chalk deposits of the Trubi Fm. The Lower Gypsum unit (massive gypsum with cm-sized selenite crystals) will be visited along the beach of Siculiana Marina (about 15 km NW of Agrigento). Next, we will visit near Capo Rossello (about 10 km NW of Agrigento) an outcrop of the Upper Gypsum unit consisting of clay-gypsum cycles and overlain by the Trubi Fm. The latter, at Scala dei Turchi beach, consists of chalk deposits arranged in a spectacular thick succession (~120 m thick) interpreted as astronomically-controlled depositional cycles. The uppermost interval of the MSC sedimentary record, including the Messinian-Zanclean GSSP, will be observed along the beach of Eraclea Minoa located about 20 km NW of Capo Rossello. Pricing Fee: €50 Attendee Limit: Min 15 - Max 50 People Registration Deadline: 11 April 2024 Field Trip Rendezvous Point Hotel nH Palermo Field Trip Leaders Antonio Caruso University of Palermo Attilio Sulli University of Palermo

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American Association of Petroleum Geologists (AAPG)
Field Seminar
Palermo, Italy
Sunday, 21 April 2024, 8:00 a.m.–5:00 p.m.

This one-day field trip will focus on Mesozoic (Jurassic to Cretaceous) carbonates outcropping in the fold and thrust belt of western Sicily and equivalent to the aquifer complex of the Sciacca Geothermal Field located in the southwestern part of the island. Participants will have the opportunity to visit in the first stop a spectacular “drowned” carbonate-platform succession at Mt. Maranfusa located in an inactive quarry about 50 km SW of Palermo. The succession consists of Lower Jurassic peritidal cycles overlain by Middle Jurassic to Cretaceous pelagic limestone (e.g. ammonitic limestone, “chalk”) and marked by an unconformity with locally hardground. Syn-depositional Mesozoic tectonic is characterized by neptunian dykes and normal faults, whereas reverse faults, strike-slip faults, and joints are related to subsequent Cenozoic deformation. In the second stop, at Mt. San Calogero, adjacent to the picturesque coastal town of Sciacca (about 100 km south of Palermo), we will visit the surface expression of an extensive karst system linked to uprising geothermal fluids. Furthermore, we will discuss main characteristics of the Sciacca Geothermal Field and its connection to deep mantle-derived fluids. Outcrop data will be integrated with both 2D seismic lines and exploration well logs showing the stratigraphy and structure of the deep aquifer. Given the presence of faults and joints in the outcrops, this field trip can provide the participants with valuable insights into naturally fractured reservoirs at the sub-seismic scale. Pricing Fee: €50 Attendee Limit: Min15 - Max 45 People Registration Deadline: 11 April 2024 Field Trip Leaders Gianni Mallarino MOL Group Attilio Sulli University of Palermo

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American Association of Petroleum Geologists (AAPG)
Field Seminar
Banff, Canada
Saturday, 11 May 2024, 8:00 a.m.–3:00 p.m.

Time: 8:00am - 5:00pm Fee: $300 AAPG members $350 Nonmembers $200 Academic/AAPG Emeritus Members $50 discount for workshop registrants Fee Includes: Transportation Insurance Field guide Entrance fee to Banff National Park Registration available during workshop registration This field trip will focus on the structural geology of the foothills and Front Ranges of Banff. Participants will be able to view excellent field examples of structures very similar to the producing oil and gas fields in the foothills to the west of Calgary and to learn about the complexities of sub-seismic-scale deformation. The field trip starts with an introduction to the interaction between thrust front with foreland basins and the interaction of basement trends with thrust belt geometries and (conventional) hydrocarbon fields. During the 1-day trip participants will follow a dip transect from the undeformed foreland basin, the eastern edge of the foothills marked by the triangle zone, the Front Ranges boundary and end at the Main Ranges west of Banff. Field Trip Itinerary Depart from Calgary – 8:00 a.m. Stop 1: Cochrane Retreat Road Overlook Trip overview and introduction; safety and logistics comments; interaction of thrust front with foreland basin; interaction of basement trends with thrust belt geometry and (conventional) hydrocarbon field distribution; appreciation of scale for subsurface play fairway. Stop 2: Scott Lake Stop 3: The Stony Nakoda Tim’s Classic stop, with historical importance for understanding the thrust belt and thrust geometry. Part 1 of displacement gradient on a large thrust. Most importantly, toilet stop after all the Tim’s coffee and driving. Review of Mt Yamnuska from a different perspective; preview of drive through McConnell damage zone and change in HW stratigraphy.. Stop 4: Lac des Arcs Imbricate thrust sheets in the Front Ranges and Banff Formation. Stop 5: Canmore T-junction Observe complexities of sub-seismic-scale deformation in mechanically layered rocks in the footwall of a large thrust Stop 6: Canmore strike view of the Rundle thrust Exposed strike view analogous to a cut-away of a giant conventional Foothills hydrocarbon field such as Turner Valley. Cross faults within the thrust sheet offset potential reservoir units at sub-seismic scale. Cross faults are arguably part of a regional trend associated with deeper, basement-rooted NE-SW structures. Stop 7: Mt Norquay Overlook Stop 8: Bow Falls Fracture systems in the Vega Siltstone Mbr of the Triassic Sulphur Mtn Fm. This outcrop of Vega Member siltstone of the Sulphur Mtn Fm is considered equivalent to upper Montney Fm. We will focus on the outcrop adjacent to the steps up to the Falls overlook.

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American Association of Petroleum Geologists (AAPG)
Workshop
Palermo, Italy
Monday, 22 April Wednesday, 24 April 2024, 8:00 a.m.–5:00 p.m.

This Symposium marks a collaborative event that brings together AAPG Europe and AAPG Middle East, with a central focus on carbonates and mixed carbonate systems worldwide, while highlighting their significance within these two regions. The primary objectives are an overview of controls that govern the evolution of these systems in time and space and the characterization and prediction of their properties across scales.

American Association of Petroleum Geologists (AAPG)
Workshop
Abu Dhabi, UAE
Monday, 27 May Wednesday, 29 May 2024, 8:00 a.m.–5:00 p.m.

In order to support the energy transition, optimizing exploration and production from complex stratigraphic-diagenetic conventional and unconventional plays remains highly important. At the same time, Carbon Capture and Storage (CCS) poses new technological challenges that will impact both the industry and academia for decades to come. This 2nd edition will present reviews and discuss technology developments in geological process-based forward modeling achieved during the last 2 years. New perspectives for future technology developments and implementation in industry workflows will be discussed and with the additional focus on CO₂ storage and other sustainability-related applications, the scope of the workshop will be considerably extended.

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

This seminar focuses on the role geoscience leaders and mentors play in retaining top talent.

American Association of Petroleum Geologists (AAPG)
Online e-Symposium
Thursday, 21 February 2013, 12:00 a.m.–12:00 a.m.

The course will review core data, petrophysical comparisons, rock physics modeling (including pseudo logs and mechanical properties).

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
Wednesday, 29 November 2023, 9:00 a.m.–10:00 a.m.

Join us for November’s AAPG Women's Network 2023 Short-Short Course Series on Wednesday, November 29th from 9-11 am (CT) with Dr. Alicia Kahn to discuss biostratigraphy and micropaleontology, largely as it pertains to oil and gas exploration.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Thursday, 19 November 2020, 12:00 p.m.–1:00 p.m.

Another in a series of AAPG Visiting Geoscientist Presentations organized by the Manchester University AAPG Student Chapter. Sponsored by BP. Presented by Visiting Geoscientist Elda Miramontes, University of Bermen, Germany Webinar presented via Zoom on 19 November at 5:00pm (GMT-0)

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Wednesday, 12 May 2021, 7:00 p.m.–8:30 p.m.

Join us for 'Pivoting 2021: Opportunities with Earth Imaging Technologies'. Panelists discuss the newest developments and directions in drones, satellite imagery, and other ways to acquire and process images of the Earth's surface. Webinar will be presented via Zoom 7pm - 8:30pm CDT, 12 May 2021.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Tuesday, 2 June 2020, 6:00 p.m.–7:00 p.m.

Visiting Geoscientist Xavier Moonan provides an overview of the destruction in the Los Iros area following the 6.9 magnitude earthquake that hit Trinidad and Tobago in 2018. His talk focuses on understanding the results from various post-earthquake studies conducted on the Los Iros, reviewing the theories developed to explain the origin and integrating datasets to provide an understanding of what transpired.

American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Tuesday, 18 August 2020, 8:00 a.m.–9:00 a.m.

Fossil fuels have led to a profound increase in world living standards but resulting emissions of CO2 and methane into the atmosphere are a primary factor in climate change. Atmospheric content of CO2 and methane have risen 146% and 257% respectively since pre-industrial time and the rate of increase through 2019 has accelerated. If significant steps are not taken in the coming decade to halt the increase in greenhouse gas emissions (GHG), a phase may be reached in the 2030-2050-time frame described as a “tipping point”, in which steady changes may be replaced by a large-scale change in the climate system. The Middle East is an area of high climate change vulnerability in the coming decades due to extreme temperatures, sea level rise and changing weather patterns.

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American Association of Petroleum Geologists (AAPG)
Online Traditional Course
Tuesday, 1 January 2013, 12:00 a.m.–1:00 a.m.

In the span of a mere few months, the much of the world went from a state of exuberant self-actualization to the most primal level of survival (health, food, shelter) insecurity. Consequently, the world has changed. Shock change due to pandemic-triggered chain reactions, supply / demand and price instability, rapid technological innovation, new plays and changing markets, distributed teams and workforces, the powerful force of social media, shortages of technical expertise, and supply chain issues have come together to create new challenges and opportunities for leadership. We will analyze how the issues relate to the oil and gas business (exploration, development, oilfield services, support services, financial sector) and we will propose solutions for immediate real-world emergencies, together with longer term challenges. In addition, we will evaluate what prominent thinkers and academics have written about leadership and strategic planning.

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American Association of Petroleum Geologists (AAPG)
Webinar
Virtual Webinar
Tuesday, 9 June 2020, 4:00 p.m.–5:00 p.m.

Visiting Geoscientist Susan Morrice shares her personal experience and insight in this talk about opportunities for geoscientists. “Geoscientists have advantages ... They are Time Travellers and have open minds. Bringing this creativity and innovation to your company or starting your own! Challenging times bring silver linings!”

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

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

Three-dimensional (3D) seismic-reflection surveys provide one of the most important data types for understanding subsurface depositional systems. Quantitative analysis is commonly restricted to geophysical interpretation of elastic properties of rocks in the subsurface. Wide availability of 3D seismic-reflection data and integration provide opportunities for quantitative analysis of subsurface stratigraphic sequences. Here, we integrate traditional seismic-stratigraphic interpretation with quantitative geomorphologic analysis and numerical modeling to explore new insights into submarine-channel evolution.

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Request a visit from Jacob Covault!

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)
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

Local sea-level changes are not simply a function of global ocean volumes but also the interactions between the solid Earth, the Earth’s gravitational field and the loading and unloading of ice sheets. Contrasting behaviors between Antarctica and Scotland highlight how important the geologic structure beneath the former ice sheets is in determining the interactions between ice sheets and relative sea levels.

Request a visit from Alex Simms!

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)
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)
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

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)

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