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Regional variations in thickness and facies of clastic sediments are controlled by geographic location within a foreland basin. Preservation of facies is dependent on the original accommodation space available during deposition and ultimately by tectonic modification of the foreland in its postthrusting stages. The preservation of facies within the foreland basin and during the modification stage affects the kinds of hydrocarbon reservoirs that are present.

This is the case for the Cretaceous Mowry Shale and Frontier Formation and equivalent strata in the Rocky Mountain region of Colorado, Utah, and Wyoming. Biostratigraphically constrained isopach maps of three intervals within these formations provide a control on eustatic variations in sea level, which allow depositional patterns across dip and along strike to be interpreted in terms of relationship to thrust progression and depositional topography.

The most highly subsiding parts of the Rocky Mountain foreland basin, near the fold and thrust belt to the west, typically contain a low number of coarse-grained sandstone channels but limited sandstone reservoirs. However, where subsidence is greater than sediment supply, the foredeep contains stacked deltaic sandstones, coal, and preserved transgressive marine shales in mainly conformable successions. The main exploration play in this area is currently coalbed gas, but the enhanced coal thickness combined with a Mowry marine shale source rock indicates that a low-permeability, basin-centered play may exist somewhere along strike in a deep part of the basin.

In the slower subsiding parts of the foreland basin, marginal marine and fluvial sandstones are amalgamated and compartmentalized by unconformities, providing conditions for the development of stratigraphic and combination traps, especially in areas of repeated reactivation. Areas of medium accommodation in the most distal parts of the foreland contain isolated marginal marine shoreface and deltaic sandstones that were deposited at or near sea level lowstand and were reworked landward by ravinement and longshore currents by storms creating stratigraphic or combination traps enclosed with marine shale seals.

Paleogeographic reconstructions are used to show exploration fairways of the different play types present in the Laramide-modified, Cretaceous foreland basin. Existing oil and gas fields from these plays show a relatively consistent volume of hydrocarbons, which results from the partitioning of facies within the different parts of the foreland basin.

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Thus far, the subject of deep-marine sands emplaced by baroclinic currents associated with internal waves and internal tides as potential reservoirs has remained an alien topic in petroleum exploration. Internal waves are gravity waves that oscillate along oceanic pycnoclines. Internal tides are internal waves with a tidal frequency. Internal solitary waves (i.e., solitons), the most common type, are commonly generated near the shelf edge (100–200 m [328–656 ft] in bathymetry) and in the deep ocean over areas of sea-floor irregularities, such as mid-ocean ridges, seamounts, and guyots. Empirical data from 51 locations in the Atlantic, Pacific, Indian, Arctic, and Antarctic oceans reveal that internal solitary waves travel in packets. Internal waves commonly exhibit (1) higher wave amplitudes (5–50 m [16–164 ft]) than surface waves (lt2 m [6.56 ft]), (2) longer wavelengths (0.5–15 km [0.31–9 mi]) than surface waves (100 m [328 ft]), (3) longer wave periods (5–50 min) than surface waves (9–10 s), and (4) higher wave speeds (0.5–2 m s–1 [1.64–6.56 ft s–1]) than surface waves (25 cm s–1 [10 in. s–1]). Maximum speeds of 48 cm s–1 (19 in. s–1) for baroclinic currents were measured on guyots. However, core-based sedimentologic studies of modern sediments emplaced by baroclinic currents on continental slopes, in submarine canyons, and on submarine guyots are lacking. No cogent sedimentologic or seismic criteria exist for distinguishing ancient counterparts. Outcrop-based facies models of these deposits are untenable. Therefore, potential exists for misinterpreting deep-marine baroclinic sands as turbidites, contourites, basin-floor fans, and others. Economic risks associated with such misinterpretations could be real.
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Integrated three-dimensional (3-D) paleomorphologic and sedimentary modeling was used to predict the basin architecture and depositional pattern of Pleistocene forearc basin turbidites in a gas hydrate field along the northeast Nankai Trough, off central Japan. Structural unfolding and stratigraphic decompaction of the targeted stratigraphic unit resulted in successful modeling of the paleobathymetry at the time of deposition. This paleobathymetry was characterized by a simple U-shaped paleominibasin. Subsequent turbidity current modeling on the reconstructed paleobathymetric surface demonstrated morphologically controlled turbidity current behavior and selective turbidite sand distribution within the minibasin, which strongly suggests the development of a confined turbidite system. Among three candidate inflow patterns, a northeasterly inflow pattern was determined as most likely. In this scenario, flow reflection and deflection caused ponding and a concentration of sandy turbidite accumulation in the basin center, which facilitated filling of the minibasin. Such a sedimentary character is undetected by seismic data in the studied gas hydrate reservoir formation because of hydrate-cementation–induced seismic anomalies. Our model suggests that 3-D horizon surfaces mapped from 3-D seismic data along with well-log data can be used to predict paleobasin characteristics and depositional processes in deep-water turbidite systems even if seismic profiles cannot be determined because of the presence of gas hydrates.
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A recent study has been completed comparing North American and European shale gas and oil resource systems.

American Association of Petroleum Geologists (AAPG)
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We use samples from undeformed and deformed sandstones (single deformation band, deformation band cluster, slip-surface cataclasite, and fault core slip zone) to characterize their petrophysical properties (porosity, permeability, and capillary pressure). Relationships between permeability and porosity are described by power-law regressions where the power-law exponent (D) decreases with the increasing degree of deformation (strain) experienced by the sample from host rock (D, sim9) to fault core (D, sim5). The approaches introduced in this work will allow geologists to use permeability and/or porosity measurements to estimate the capillary pressures and sealing capacity of different fault-related rocks without requiring direct laboratory measurements of capillary pressure. Results show that fault core slip zones have the highest theoretical sealing capacity (gt140-m [459-ft] oil column in extreme cases), although our calculations suggest that deformation bands can locally act as efficiently as fault core slip zones in sealing nonwetting fluids (in this study, oil and CO2). Higher interfacial tension between brine and CO2 (because of the sensitivity of CO2 to temperature and pressure) results in higher capillary pressure and sealing capacity in a brine and CO2 system than a brine and oil system for the same samples.
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Reservoir properties of Upper Triassic–Middle Jurassic sandstones, Spitsbergen, are studied as part of a CO2 storage pilot project in Longyearbyen. The reservoir formations show large contrasts in sandstone compositions, with unexpected low permeability despite moderate porosity values. Petrographic analyses were performed to investigate the influence and distribution of diagenesis. It is concluded that, because of various compaction, cementation, and dissolution processes, the sandstone porosity is mainly isolated molds and micropores and associated with fibrous illite and chamosite, explaining the low permeability. Diagenesis and the distribution of quartz cement is influenced by lithofacies and detrital compositions. Mineralogically immature sandstones (De Geerdalen Formation) show a homogeneous distribution of quartz cement overgrowths on quartz grains, distributed interstitial to labile grains and other cements (e.g., late calcite). The main silica source was from the dissolution of adjacent feldspar and labile grains as part of the chemical compaction. In contrast, quartz-dominated sandstones (Knorringfjellet Formation) show a heterogeneous patchy distribution of quartz cement influenced by the sedimentary bioturbation pattern, with silica sourced also from dissolution at clay-rich microstylolites. Phosphatic beds at the base and top of the formation are strongly influenced by marine eogenesis and reworking processes and associated with concentration of iron-rich authigenic minerals. The highest porosity appears in sand-supported conglomerate where moldic clay-mineral ooids contributed to reduce quartz cementation. The stratigraphic change from mineralogical immature (Triassic) to mature (uppermost Triassic–Jurassic) sandstone compositions is detected in wide areas of the Barents Shelf and has considerable implications for the distribution of sandstone reservoir properties.
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Estimation of the dimensions of fluvial geobodies from core data is a notoriously difficult problem in reservoir modeling. To try and improve such estimates and, hence, reduce uncertainty in geomodels, data on dunes, unit bars, cross-bar channels, and compound bars and their associated deposits are presented herein from the sand-bed braided South Saskatchewan River, Canada. These data are used to test models that relate the scale of the formative bed forms to the dimensions of the preserved deposits and, therefore, provide an insight as to how such deposits may be preserved over geologic time. The preservation of bed-form geometry is quantified by comparing the alluvial architecture above and below the maximum erosion depth of the modern channel deposits. This comparison shows that there is no significant difference in the mean set thickness of dune cross-strata above and below the basal erosion surface of the contemporary channel, thus suggesting that dimensional relationships between dune deposits and the formative bed-form dimensions are likely to be valid from both recent and older deposits.

The data show that estimates of mean bankfull flow depth derived from dune, unit bar, and cross-bar channel deposits are all very similar. Thus, the use of all these metrics together can provide a useful check that all components and scales of the alluvial architecture have been identified correctly when building reservoir models. The data also highlight several practical issues with identifying and applying data relating to cross-strata. For example, the deposits of unit bars were found to be severely truncated in length and width, with only approximately 10% of the mean bar-form length remaining, and thus making identification in section difficult. For similar reasons, the deposits of compound bars were found to be especially difficult to recognize, and hence, estimates of channel depth based on this method may be problematic. Where only core data are available (i.e., no outcrop data exist), formative flow depths are suggested to be best reconstructed using cross-strata formed by dunes. However, theoretical relationships between the distribution of set thicknesses and formative dune height are found to result in slight overestimates of the latter and, hence, mean bankfull flow depths derived from these measurements.

This article illustrates that the preservation of fluvial cross-strata and, thus, the paleohydraulic inferences that can be drawn from them, are a function of the ratio of the size and migration rate of bed forms and the time scale of aggradation and channel migration. These factors must thus be considered when deciding on appropriate length:thickness ratios for the purposes of object-based modeling in reservoir characterization.

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“My concept of reservoirs has completely changed.”

American Association of Petroleum Geologists (AAPG)
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It don’t come easy: The oil rich Monterey Shale has proved to be the biggest conventional resource provider in California, and it promises even more – but the formation’s complex geology is just as intimidating as its potential is huge.

American Association of Petroleum Geologists (AAPG)
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This study documents that Danian-aged sand remobilization of deep-water slope-channel complexes and intrusion of fluidized sand into hydraulically fractured slope mudstones of the Great Valley sequence, California, generated 400-m (1312 ft)–thick reservoir units: unit 1, parent unit channel complexes for shallower sandstone intrusions; unit 2, a moderate net-to-gross interval (0.19 sand) of sills with staggered, stepped, and multilayer geometries with well-developed lateral sandstone-body connectivity; unit 3, a low net-to-gross interval (0.08 sand) of exclusively high-angle dikes with good vertical connectivity; and unit 4, an interval of extrusive sandstone. Unit 2 was formed during a phase of fluidization that emplaced on an average 0.19 km3 (0.046 mi3) of sand per cubic kilometer of host sediment. Probe permeametry data reveal a positive relationship between sill thickness and permeability. Reservoir quality is reduced by the presence of fragments of host strata, such as the incorporation of large rafts of mudstone, which are formed by in-situ hydraulic fracturing during sand injection. Mudstone clasts and clay- and silt-size particles generated by intrusion-induced abrasion of the host strata reduce sandstone permeability in multilayer sills (70 md) when compared to that in staggered and stepped sills (586 and 1225 md, respectively). Post-injection cementation greatly reduces permeability in high-angle dikes (81 md). This architecturally based reservoir zonation and trends in reservoir characteristics in dikes and sills form a basis for quantitative reservoir modeling and can be used to support conceptual interpretations that infer injectite architecture in situations where sands in low net-to-gross intervals are anticipated to have well-developed lateral and vertical connectivity.
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In-Person Training
Buenos Aires Argentina 16 November, 2016 18 November, 2016 33655 Desktop /Portals/0/PackFlashItemImages/WebReady/lacr-gtw-moving-toward-the-prediction-of-unconventional-plays-hero-new.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true Development and Operations, Engineering, Directional Drilling, Production, Hydraulic Fracturing, Reservoir Characterization, Geochemistry and Basin Modeling, Oil and Gas Analysis, Source Rock, Geophysics, Seismic, Petrophysics and Well Logs, Carbonates, Sedimentology and Stratigraphy, (Carbonate) Shelf Sand Deposits, Clastics, Deep Sea / Deepwater, Marine, Transgressive Deposits, Slope, Structure, Geomechanics and Fracture Analysis, Structural Analysis (Other), Oil Shale, Shale Gas
Buenos Aires, Argentina
16-18 November 2016

Join leading scientists and industry practitioners at Moving toward the Prediction of Unconventional Plays: Lessons Learned from Tight and Shale Reservoirs in Neuquén Basin, Argentina, a Geosciences Technology Workshop (GTW) hosted by the American Association of Petroleum Geologists (AAPG) and the Argentine Association of Petroleum Geologists and Geophysicists (AAGGP).

Houston Texas United States 24 January, 2017 25 January, 2017 33528 Desktop /Portals/0/PackFlashItemImages/WebReady/gtw-deepwater-shelf-2016-hero.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true Engineering, Development and Operations, Reservoir Characterization, Geochemistry and Basin Modeling, Basin Modeling, Geophysics, Clastics, Sedimentology and Stratigraphy, Deep Sea / Deepwater, Deepwater Turbidites, Shelf Sand Deposits, Structure, Structural Analysis (Other), Fractured Carbonate Reservoirs, Stratigraphic Traps, Subsalt Traps
Houston, Texas, United States
24-25 January 2017

The goal of this event is to bring together new technologies and developments in both exploring for new frontiers and developing known provinces in both deepwater and shelf environments. The event brings together geology, geochemistry, engineering, and geophysics.

Yangon Myanmar 25 February, 2017 28 February, 2017 34027 Desktop /Portals/0/PackFlashItemImages/WebReady/AAPG-EAGE-MGS-Myanmar-Geosciences-Conference-Hero-v2.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true Structure, Geochemistry and Basin Modeling, Sedimentology and Stratigraphy, Business and Economics, Engineering, Basin Modeling, Petroleum Systems, Oil and Gas Analysis, Maturation, Clastics, Carbonates, Evaporites, Economics, Reservoir Characterization, Development and Operations, Production
Yangon, Myanmar
25-28 February 2017

The Myanmar Geosciences Society will offer a 4-day/3-night field trip to the Kalaw Basin to visit Mesozoic sediments of Kialaw Basin and view conspicuous surface geologic expressions of Sagaing Strike Slip Fault and Shan Boundary fault (Suture Zone), as well as various Paleozoic to Tertiary outcrops along the road sections.

Dar Es Salaam Tanzania 06 March, 2017 08 March, 2017 33259 Desktop /Portals/0/PackFlashItemImages/WebReady/sc-ar-sequence-stratigraphy-tanzania-hero-1.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true Sedimentology and Stratigraphy, Business and Economics, Engineering, Clastics, Carbonates, Reserve Estimation, Reservoir Characterization, Production, Bitumen/Heavy Oil, Coalbed Methane, Stratigraphic Traps, Subsalt Traps
Dar Es Salaam, Tanzania
6-8 March 2017

The paradigm of sequence stratigraphy has entered a new phase and these once revolutionary concepts are now applied in pre-drill exploration at ever-increasing resolution. The concepts also prove useful in production geology, especially in enhanced oil recovery efforts in previously abandoned fields.

Windhoek Namibia 10 April, 2017 12 April, 2017 33241 Desktop /Portals/0/PackFlashItemImages/WebReady/sc-ar-sequence-stratigraphy-a-predictive-tool-for-e-p-industry-hero-1.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true Engineering, Production, Reservoir Characterization, Sedimentology and Stratigraphy, Carbonates, Clastics, Coalbed Methane, Bitumen/Heavy Oil, Subsalt Traps, Stratigraphic Traps, Business and Economics, Reserve Estimation
Windhoek, Namibia
10-12 April 2017

The paradigm of sequence stratigraphy has entered a new phase and these once revolutionary concepts are now applied in pre-drill exploration at ever-increasing resolution. The concepts also prove useful in production geology, especially in enhanced oil recovery efforts in previously abandoned fields.

Kampala Uganda 29 May, 2017 31 May, 2017 33266 Desktop /Portals/0/PackFlashItemImages/WebReady/sc-ar-sequence-stratigraphy-uganda-hero-1.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true Sedimentology and Stratigraphy, Business and Economics, Engineering, Clastics, Carbonates, Reserve Estimation, Reservoir Characterization, Production, Bitumen/Heavy Oil, Coalbed Methane, Stratigraphic Traps, Subsalt Traps
Kampala, Uganda
29-31 May 2017

The paradigm of sequence stratigraphy has entered a new phase and these once revolutionary concepts are now applied in pre-drill exploration at ever-increasing resolution. The concepts also prove useful in production geology, especially in enhanced oil recovery efforts in previously abandoned fields.

Online Training
08 December, 2011 08 December, 2011 1480 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-connectivity-in-fluvial-systems.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
8 December 2011

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

01 January, 2013 01 January, 9999 1459 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-cc-giant-oil-and-gas-fields.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
1 January 2013 - 1 January 9999

There are more approximately 1,000 oil and gas fields in the world that have been classified as "giant," containing more than 500 million barrels of recoverable oil and /or 3 trillion cubic feet of gas.

24 October, 2013 24 October, 2013 1499 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-geomechanical-data-from-petrophysical-logs.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
24 October 2013

This e-symposium will be introducing signal processing techniques as a means to maximize extracting geomechanical data from petrophysical logs.

13 December, 2012 13 December, 2012 1494 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-petrophysics-of-shales.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
13 December 2012

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

07 November, 2013 07 November, 2013 1500 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-from-qualitative-to-quantitative-interpretations.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
7 November 2013

This e-symposium presentation places the interpretation of deep-water turbidites discernible in 3-D seismic inversion data within a geological context.

28 April, 2011 28 April, 2011 1471 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-niobrara-petroleum-system-a-major-tight-resource-play.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
28 April 2011

The Niobrara Petroleum System of the U.S. Rocky Mountain Region is a major tight petroleum resource play.

17 February, 2011 17 February, 2011 1469 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-siliclastic-sequence-stratigraphy.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
17 February 2011

This presentation is designed for exploration/production geologists and geological managers or reservoir engineers.

11 November, 2010 11 November, 2010 1465 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-geochemical-evaluation-of-eagle-ford-group-source.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
11 November 2010

This e-symposium is ideal for geologists, geophysicists, engineers and other geoscientists who are involved in gas shale exploration and production.

29 April, 2010 29 April, 2010 1457 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-seismic-stratigraphy-seismic-geomorphology-of-deep-water.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
29 April 2010

This presentation will focus on the seismic stratigraphic and seismic geomorphologic expression of deep-water deposits, including both reservoir and non-reservoir facies.

22 October, 2009 22 October, 2009 1452 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-fluvial-stratigraphy.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
22 October 2009

This course can help you gain the ability to describe the complex and highly variable reservoirs, which are typified by complex internal heterogeneity.

14 February, 3000 14 February, 3000 7817 Desktop /Portals/0/PackFlashItemImages/WebReady/oc-es-generic-hero.jpg?width=100&height=100&mode=crop&anchor=middlecenter&quality=75amp;encoder=freeimage&progressive=true
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