Click to minimize content

Welcome to the new Datapages Archives

Datapages has redesigned the Archives with new features. You can search from the home page or browse content from over 40 publishers and societies. Non-subscribers may now view abstracts on all items before purchasing full text. Please continue to send us your feedback at emailaddress.

AAPG Members: Your membership includes full access to the online archive of the AAPG Bulletin. Please login at Members Only. Access to full text from other collections requires a subscription or pay-per-view document purchase.

Click to maximize content

Welcome to the new Datapages Archives

Search Results   > New Search > Revise Search

The AAPG/Datapages Combined Publications Database

Showing 3,149 Results. Searched 197,286 documents.

< Previous   10   11   12   13   14   Next >

Ascending

Sphericity Determinations of Pebbles and Sand Grains

Willard D. Pye, Margaret Hurst Pye

Journal of Sedimentary Research (SEPM)

... and sand grains is simply and rapidly determined by taking ratios of the diameters of the particles. It is proved that for ellipsoidal and spherical shaped...

1943

Heterogeneous Distribution of Calcite Cement at the Outcrop Scale in Tertiary Sandstones, Northern Apennines, Italy

Earle F. McBride , Kitty L. Milliken , William Cavazza , Ubaldo Cibin , Daniela Fontana , M. Dane Picard , Gian Gaspare Zuffa

AAPG Bulletin

... localized hydrologic factors in determining the spatial distribution of authigenic pore-filling calcite. Spherical concretions grew by diffusive supply...

1995

Enhanced Two Dimensional Grain Size Analysis through the Use of Calibrated Digital Petrography, #41461 (2014).

O. Hinds, R.A. Duller, R.P. Walker, B.T. Wells, R.H. Worden

Search and Discovery.com

... the effect of size distribution and shape variation error. Three samples were made from: sample a; unimodal glass beads with spherical shape (Figure 1a...

2014

Understanding Organic Matter Structural Changes with Increasing Thermal Maturity from Oil Shale Plays through SEM Imaging

Leo Alcantar-Lopez

Unconventional Resources Technology Conference (URTEC)

... at low maturity levels (<0.7 %Ro equivalent, from T-max values) is composed of sub-spherical units, generally 7-12 nm in diameter. With increasing...

2016

Determination of Drag Coefficients in Measuring Particle Diameters

Weinan Chen

Journal of Sedimentary Research (SEPM)

... for estimating the contact area between a particle and the fluid, which is critical in calculating the nondimensional drag coefficient (CD). When a spherical...

2003

Cave Pearls and Pisoliths: A Sedimentological Comparison

Carol A. Hill

West Texas Geological Society

... Cave, Guadalupe Mountains, New Mexico (Nymeyer, 1938). Shape is typically spheroidal for both pisoliths and cave pearls, but can vary from spherical...

1992

Practical Significance of Birdseye Structures in Carbonate Rocks

E. A. Shinn

Journal of Sedimentary Research (SEPM)

.... Birdseye vugs, shown in figure 7, formed both under the heat lamp and outdoors under the sun. Both spherical and planar types, similar to those described...

1968

Estimation of In-Situ Wettability using Multi-Frequency Electromagnetic Measurements

Yuteng Jin, Siddharth Misra, Dean Homan

Unconventional Resources Technology Conference (URTEC)

... and nonconductive phase on the surface of a spherical particle. The wetting phase will try to surround the solid particle to satisfy the contact angle...

2020

Volcanic effects on microplankton during the Permian…Triassic Transition (Shangsi and Xinmin, South China)

Jun Shen, Yong Lei, Thomas J. Algeo, Qinglai Feng, Thomas Servais, Jianxin Yu, Lian Zhou

PALAIOS

... but acritarchs reached their peak abundance, confirming their role as a disaster taxon. Above the LPME, long-spined and small spherical acritarchs...

2013

The Influence of Plants and Micro-Organisms on Diagenesis in Caliche: Example from the Pleistocene Ironshore Formation on Cayman Brac, British West Indies

Brian Jones

CSPG Bulletin

... and spherical bodies ((Fig. 7D-F)), and (4) calcified hemispherical and spherical bodies ((Fig. 7A-C)). UNCALCIFIED FILAMENTS The uncalcified filaments...

1988

Scanning Electron Microscope Petrographic Differentiation among Different Types of Pores Associated with Organic Matter in Mudrocks

Robert M. Reed, Robert G. Loucks, Lucy T. Ko

GCAGS Journal

...). These pores can be highly variable in size (nanometers to micrometers) and shape (spherical to cubic to highly irregular). Inherited pores occur...

2020

Recognition of Sandstone Depositional Environment: A Grain Shape Approach, with an Example from North Padre Island

Jim Mazzullo , Donald Sims

GCAGS Transactions

... that spherical sand grains have a strong tendency to move under the influence of the wind, while less spherical grains tend to lag behind. Mattox (1955), however...

1983

Marcasite in Black Shales—a Mineral Proxy for Oxygenated Bottom Waters and Intermittent Oxidation of Carbonaceous Muds

Juergen Schieber

Journal of Sedimentary Research (SEPM)

... and is closely associated with irregular patches of pyrite microcrysts and remnant spherical shapes consisting of pyrite microcrysts (Fig. 2A). Features...

2011

Early Diagenetic Silica Deposition in Algal Cysts and Spores: A Source of Sand in Black Shales?

Jurgen Schieber

Journal of Sedimentary Research (SEPM)

... of compaction, a small proportion are filled with diagenetic silica. The latter are spherical to ellipsoidal (0.1-0.5 mm), and filled with chalcedony, microquartz...

1996

Spatial Variability of Porosity in Chalk: Comparison of an Outcrop and a North Sea Reservoir

P. Frykman

AAPG Special Volumes

...- to Intermediate-scale VarianceThe model for the vertical semivariogram includes a spherical structure with range 0.20 m (0.66 ft), which accounts for 35...

2006

Morphology of Hydrocarbon Droplets During Migration: Visual Example from the Monterey Formation (Miocene), California

Neal R. O'Brien , Geoffrey D. Thyne , Roger M. Slatt

AAPG Bulletin

... pathways themselves. The small (5-10 µm) diameter droplets are observed to have various shapes that include spherical droplets, amalgamated droplets...

1996

Heavy Mineral Composition of the Cardium Formation, Pembina Oil Field

Martin Halpern

CSPG Bulletin

.... End_Page 311------------------------ Grains show conchoidal fracture and vitreous lustre. Spherical inclusions of probable solid matter (0.004...

1961

Improved Data Analysis and Interpretation Method for Laboratory Determination of Crushed-Sample Shale Gas Permeability

F. Civan, D. Devegowda, R. Sigal

Unconventional Resources Technology Conference (URTEC)

... formulation of Civan et al. (2012) is now extended for application to transport of gas in spherical-shape crushed rock samples. First, Eq.(3...

2013

Experimental Classification of Solid Carbonate Rocks on a Basis of Microscopic Organic Remains

I. V. Chubinidze

Petroleum Geology: A Digest of Russian Literature

... of planktonic foraminifera there are also radiolaria and spherical remains of probable organic origin; the latter could also be radiolaria. Upward...

1965

Armoured mud balls revisited

Lawrence H. Tanner

Atlantic Geology

..., on the north shore o f the Minas Basin. Shapes vary from nearly spherical to platy to elongate, with elongate predominant. The mud balls form from the action...

1996

Chamosite Oolites in the Devonian of Pennsylvania

Richard A. Sheppard, Ralph E. Hunter

Journal of Sedimentary Research (SEPM)

... as oolites by their nuclei and concentric structure and by their spherical form where protected from flattening after deposition. Broken oolites serving...

1960

Theory of Sieving: NOTES

Basanta K. Sahu

Journal of Sedimentary Research (SEPM)

... be conveniently classified into two groups; ellipsoidal (spherical) grains (Case I) and tabular grains (Case II). The tabular grains are further...

1965

Quiet Water Oolites from the Ordovician of Minnesota: NOTES

Richard A. Davis, Jr.

Journal of Sedimentary Research (SEPM)

... in which nuclei are not recognizable are mostly well sorted and spherical. Most recognizable nuclei are quartz grains, but some are rounded intraclasts...

1966

Modern Armored Mud Balls in an Urban Environment

Richard W. Ojakangas, Joyce A. Thompson

Journal of Sedimentary Research (SEPM)

... and armored. Spherical, subspherical, cylindrical, and elliptical shapes were observed. BELL, H. S., 1940, Armored mud balls: Their origin, properties...

1977

Abstract: An Azimuthal-AVO-Compliant 3D Land Seismic Processing Flow; #90171 (2013)

David Gray, Darren Schmidt, Nirupama Nagarajappa, Charles Ursenbach, and Jon Downton

Search and Discovery.com

...., 2001). 2. Azimuthal spherical divergence correction (Xu and Tsvankin, 2006). 3. 5D interpolation (Trad et al., 2005). 4. Migration of Common Offset...

2013

< Previous   10   11   12   13   14   Next >