Mobil

About: Mobil is a based out in . It is known for research contribution in the topics: Catalysis & Zeolite. The organization has 7085 authors who have published 10642 publications receiving 237497 citations. The organization is also known as: Socony-Vacuum Oil Company & Standard Oil Company of New York.

Grain-Size and Textural Classification of Coarse Sedimentary Particles

Abstract: The Udden-Wentworth grain-size scale is widely used as the standard for objective description of sediment, but it inadequately covers gravel, the dominant fraction in many environments such as alluvial fans. The scale is most detailed in the sand and mud fractions, where grades such as "fine sand" are defined by particle intermediate axial length (dI). We propose similar detailed grades for gravel with dI boundaries consistently determined by extending the Udden-Wentworth scheme of multiples of 2 (whole increments). The 2 to 4 mm granule class (-1 to -2 ) in this system consists of just one grade, but the pebble class comprises four: fine pebbles with dI from 4 to 8 mm (-2 to -3 ), medium pebbles from 8 to 16 mm (-3 to -4 ), coarse pebbles from 16 to 32 mm (-4 to -5 ), and very coarse pebbles from 32 to 64 mm (-5 to -6 ). Coarser grades are fine cobbles with dI from 6.4 to 12.8 cm (-6 to -7 ), coarse cobbles from 12.8 to 25.6 cm (-7 to -8 ), fine boulders from 25.6 to 51.2 cm (-8 to -9 ), medium boulders from 51.2 to 102.4 cm (-9 to -10 ), coarse boulders from 102.4 to 204.8 cm (-10 to -11 ), and very coarse boulders from 204.8 to 409.6 cm (-11 to -12 ). These terms can be used in Folk's texture classification to derive detailed descriptions such as "angular, poorly sorted, fine to coarse boulder conglomerate". This grain-size scheme is further extended to account for particles coarser than boulders (dI > 4.1 m), which we collectively call megaclasts, and the sediment they comprise megagravel or, if lithified, megaconglomerate. Megagravel is divided into four classes based on dI, including blocks from 4.1 to 65.5 m (-12 to -16 ), slabs from 65.5 to 1049 m (-16 to -20 ), monoliths from 1 to 33.6 km (-20 to -25 ), and megaliths from 33.6 to 1075 km (-25 to -30 ). The first three classes cover the coarsest sediment currently known. Their grades are fine blocks, with dI from 4.1 to 8.2 m (-12 to -13 ), medium blocks from 8.2 to 16.4 m (-13 to -14 ), coarse blocks from 16.4 to 32.8 m (-14 to -15 ), very coarse blocks from 32.8 to 65.5 m (-15 to -16 ), fine slabs from 65.5 to 131 m (-16 to -17 ), medium slabs from 131 to 262 m (-17 to -18 ), coarse slabs from 262 to 524 m (-18 to -19 ), very coarse slabs from 524 to 1049 m (-19 to -20 ), very fine monoliths from 1.0 to 2.1 km (-20 to -21 ), fine monoliths from 2.1 to 4.2 km (-21 to -22 ), medium monoliths from 4.2 to 8.4 km (-22 to -23 ), coarse monoliths from 8.4 to 16.8 km (-23 to -24 ), and very coarse monoliths from 16.8 to 33.6 km (-24 to -25 ). These grades also can be used in Folk's texture classification for objective sediment description. We reserve the megalith class and five attendant grades for even coarser megaclasts, with dI spanning from 33.6 to 1075.2 km (-25 to -30 ).

New direct observations of asphalts and asphalt binders by scanning electron microscopy and atomic force microscopy

Abstract: Observations made using AFM and SEM have been combined in order to study the structure of asphalts. Fluorescence microscopy was used to aid in understanding the structural changes occurring when polymer is added to the asphalts. With the atomic force microscope we are able to study the structure of the asphalts without any pre-preparation. Despite very low resolution, our study reveal ed a network of asphaltene molecules with regard to asphalt gel. The same result is obtained by SEM observation but with a much better resolution. SEM observation, however, needs an adequate preparation method. In the presence of polymer we observed a rearrangement of the initial asphaltene association which leads to the assumption that polymer can aggregate the asphaltene phase.

Bacterially Induced Lithification of Microbial Mats

Abstract: Below the photic zone within live microbial mats from tidal flats, the cyanobacteria are dead and bacteria are the dominant living biota. Field data indicate that precipitation of calcium carbonate occurs predominantly within the mats in the aphotic zone. In order to determine whether bacteria could be responsible for inducing the precipitation of calcium carbonate within the microbial mats, live microbial mats and bacteria were collected from modern tidal flats. Over 50 experiments were set up in the laboratory in which live, naturally dead, and sterilized (autoclaved) dead filamentous cyanobacteria were inoculated with bacterial cultures

Framework for AVO gradient and intercept interpretation

Abstract: Amplitude variation with offset (AVO) interpretation may be facilitated by crossplotting the AVO intercept (A) and gradient (B). Under a variety of reasonable petrophysical assumptions, brine‐saturated sandstones and shales follow a well‐defined “background” trend in the A-B plane. Generally, A and B are negatively correlated for “background” rocks, but they may be positively correlated at very high VP/VS ratios, such as may occur in very soft shallow sediments. Thus, even fully brine‐saturated shallow events with large reflection coefficients may exhibit large increases in AVO. Deviations from the background trend may be indicative of hydrocarbons or lithologies with anomalous elastic properties. However, in contrast to the common assumptions that gas‐sand amplitude increases with offset, or that the reflection coefficient becomes more negative with increasing offset, gas sands may exhibit a variety of AVO behaviors. A classification of gas sands based on location in the A-B plane, rather than on normal‐...

Conversion of synthesis gas to hydrocarbon mixtures

Abstract: Synthesis gas is contacted with an intimate mixture of a carbon monoxide hydrogen reduction catalyst, comprising a methanol synthesis catalyst in combination with a selective class of acidic crystalline aluminosilicate having a silica/alumina ratio greater than 12, a pore dimension greater than about 5 Angstroms to produce hydrocarbon mixtures useful in the manufacture of heating fuels, gasoline, aromatic hydrocarbons, and chemicals intermediates