GEOCHEMICAL INTERPRETATION OF SOME OILS AND CONDENSATES FROM THE DAMPIER SUB- BASIN OF WESTERN AUSTRALIA

1982 ◽  
Vol 22 (1) ◽  
pp. 179 ◽  
Author(s):  
I. Brikké
Keyword(s):  
Chemical Composition ◽  
Western Australia ◽  
Land Plant ◽  
Early Triassic ◽  
Normal Alkane ◽  
Geological Interpretation ◽  
The Core ◽  
Strong Affinity ◽  
Strong Emphasis ◽  
Deep Source

Twenty oils and condensates from the Dampier Sub-basin have been analysed for their gross composition and normal alkane distribution.The chemical composition (GLC traces) enables two groups to be distinguished:Oils and condensates low in C22 + n-alkanes. These are essentially found in the Rankin Platform. In this group, the sample from Eaglehawk 1 shows characteristics of a bacterially-altered product.Oils richer in C22 + n-alkanes. These are found in the Lewis Trough, but also in the Rankin Platform/Kendrew Terrace where subtle differences may suggest different origins.The geological interpretation puts strong emphasis on time of trapping. The oils and condensates of the first group (except at Angel) are trapped at the contact with the 'Main Unconformity'. Oils formed earlier than the Neocomian have been destroyed, altered (Eaglehawk 1) or trapped in deeper reservoirs, so that only mature to very mature hydrocarbons (low in C22 + n-alkanes) were available for trapping after sealing by Neocomian shales. Maturity considerations indicate that a deep source within the core of the Rankin Platform unit (Middle/Early Triassic Locker Shale and/or older) is the most likely generator of these hydrocarbons.The oils of the second group, on maturity grounds and to some extent on type correlation, may originate from Jurassic sources in the Lewis Trough. Some oils attributable to the second group are present on the Rankin Platform and/or Kendrew Terrace trapped by intraformational/fault seals and having the full composition of crudes; however, lower land-plant contribution inferred from the n-alkanes, suggests a 'Locker Shale' origin.The source of the Angel hydrocarbons is more enigmatic, but their strong affinity with the hydrocarbons from the Rankin Platform points to a similarity of origin.

Hydrogeochemical and isotopic characterization of groundwater at Žitný Island (SW Slovakia)

2015 ◽  
Vol 46 (6) ◽  
pp. 929-942 ◽  
Author(s):  
Z. Ženišová ◽  
P. P. Povinec ◽  
A. Šivo ◽  
R. Breier ◽  
M. Richtáriková ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Surface Water ◽  
Danube River ◽  
Water Isotopes ◽  
Anthropogenic Contamination ◽  
The Danube River ◽  
The Core ◽  
Groundwater Reservoir ◽  
Isotopic Characterization

Hydrogeochemical investigations and spatial variations studies on the distribution of water isotopes and radiocarbon in the groundwater of Žitný Island (Rye Island) were carried out. Žitný Island represents the largest groundwater reservoir in Central Europe (about 10 Gm3). The chemical composition of the groundwater of Žitný Island depends mainly on the chemical composition of Danube water, as well as on the length of its infiltration from the Danube River. The groundwater is characterized by potamogenic mineralization, and its chemical composition is influenced by anthropogenic contamination. Sub-surface water profiles showed enriched δ18O levels up to around 20 m water depth, and depleted values for deeper waters. The observed isotopic composition of the groundwater is similar to Danube water, suggesting that the Danube River is the main source of the Žitný Island groundwater. The core of the sub-surface 14C profile represents contemporary groundwater with 14C values above 80 pMC.

scholarly journals On Some Peculiar Features in the Sequences of the Old Open Star Clusters

1974 ◽  
Vol 59 ◽  
pp. 109-111
Author(s):  
A. Maeder
Keyword(s):  
Chemical Composition ◽  
Stellar Evolution ◽  
Main Sequence ◽  
Star Clusters ◽  
Open Star Clusters ◽  
Hydrogen Burning ◽  
The Core ◽  
Open Star ◽  
Solar Type ◽  
Good Agreement

In spite of the rather good agreement between the theory of stellar evolution and the observations, there exist some difficulties when one compares closely the sequences of open star clusters and the theoretical isochrones. Several, if not all, of the old open star clusters seem to be concerned, especially those which are accurately measured, namely Praesepe, NGC 2360, 752, 3680 and M67. The problem concerns the gap occuring in the HR diagram at the end of the phase of hydrogen burning in the core; it corresponds to the phase of hydrogen exhaustion (or of overall contraction). The sequence of M67 has been studied by Racine (1971) and Torres-Peimbert (1971). The well apparent gap is located farther from the zero-age main sequence than indicated by the models and the hook towards a larger Teff predicted during this phase is not observed. Differences in chemical composition may not be held responsible for these anomalies. From Torres-Peimbert's models, it may be assumed that neither solar type, nor super metal rich composition are able to reduce the discrepancies. As a further illustration, let us mention the case of NGC 752. In Table I, the main features related to the gap are examined: the disagreement, like in M67, essentially concern features 1 and 2. The observations are based on a recent study of Grenon and Mermillod (1973) and on Bell's data (1972). Bell has also mentioned the existence of discrepancies. As in M67, the gap is too far from the zero-age main sequence and does not present any sudden turning towards a larger Teff.

scholarly journals Optical and X-ray observations of stellar winds in Wolf-Rayet binaries

1995 ◽  
Vol 163 ◽  
pp. 262-270
Author(s):  
A. M. Cherepashchuk
Keyword(s):  
Chemical Composition ◽  
Core Temperature ◽  
Stellar Winds ◽  
Radial Expansion ◽  
Core Radius ◽  
X Ray ◽  
The Core ◽  
Basic Conclusion ◽  
Helium Stars ◽  
Colliding Winds

New spectrophotometric, photometric and polarimetric observations of V444 Cygni confirm the basic conclusion that the WN5 star has a small core radius (rc < 4 R⊙) and a high core temperature (Tc > 60 000 K), which are characteristic of massive helium stars. Values of rc < 3 — 6 R⊙ and Tc > 70 000 — 90 000 K for the core of the WN7 star in the Cygnus X-3 system agree well with this conclusion. A clumping structure of WR winds is suggested. X-ray observations of colliding winds in WR+O binaries suggest radial expansion and anomalous chemical composition of WR winds.

scholarly journals Nucleation and Initial Growth of Garnet in Low-Grade Metamorphic Rocks of the Sanbagawa Metamorphic Belt, Kanto Mountains, Japan

Minerals ◽  
2020 ◽  
Vol 10 (3) ◽  
pp. 292 ◽  
Author(s):  
Mutsuko Inui ◽  
Yumenosuke Wakai ◽  
Hiirou Sakuragi
Keyword(s):  
Chemical Composition ◽  
Size Distribution ◽  
Crystal Size ◽  
Crystal Size Distribution ◽  
Garnet Growth ◽  
Low Grade ◽  
Initial Growth ◽  
Metamorphic Belt ◽  
The Core ◽  
Log Normal

The beginning of the recrystallization of minerals within a subducting oceanic plate provides a valuable record of dehydration within the subduction zone. Pelitic schists of the Nagatoro area, Kanto Mountains, Japan, record the initial stages of garnet growth. Consequently, these rocks were studied to analyze garnet nucleation and growth during metamorphism of the Sanbagawa metamorphic belt, one of the world’s most comprehensively studied subduction complexes. The garnet grains are small, euhedral, and occur only within micaceous lamellae that define the schistosity. Crystal size distribution analyses revealed most of the garnet grains follow the log-normal size distribution, indicating that they formed in the same event. A few exceptionally large garnet grains exist that do not seem to follow the log-normal distribution. The latter garnet grains contain a rounded fragmental area with a different chemical composition inside the core. It is possible that detrital fragments of garnet contribute to the irregular crystal size distribution of garnet in the studied area. Many of the smaller (log-normal) garnet grains have relatively large, homogeneous Mn-rich cores. The lack of chemical zoning within the garnet cores suggests that they grew under constant pressure and temperature in response to overstepping of the garnet-in reaction. The chemical composition changes very sharply at the boundary between the core and the surrounding mantle. The size of the Mn-rich core is different from sample to sample, suggesting that the nucleation was controlled by the local chemical condition of each sample.

An insect glycoprotein: a study of the particles responsible for the resistance of a parasitoid’s egg to the defence reactions of its insect host

1979 ◽  
Vol 205 (1159) ◽  
pp. 271-286 ◽  
Keyword(s):  
Chemical Composition ◽  
Nucleic Acid ◽  
Molecular Mass ◽  
Single Particle ◽  
Physical Structure ◽  
Insect Host ◽  
Small Particles ◽  
The Core ◽  
Structural Subunit ◽  
Defence Reactions

A study has been carried out of the chemical composition and physical structure of small particles, 130 nm in diameter, isolated from the calyx of the ichneumon, Nemeritis canescens. The particles are vesicular, con­sisting of a densely-staining core surrounded by an outer membrane. The core of the particles is made up of protein and carbohydrate in the ratio 100 : 17; no nucleic acid was detected. The basic chemical subunit of the core of the particles appears to be a glycoprotein of molecular mass ca . 45000. The basic structural subunit of the core, however, is a short, hollow cylinder, about 10 nm across. It seems likely that several chemical subunits make up one structural subunit, and that many structural subunits, surrounded by the membrane, make up a single particle.

Study on the Influence of High Temperature Homogenizing and Solution on the Microstructure and Property of 4Cr5MoSiV1 Steel

2012 ◽  
Vol 549 ◽  
pp. 567-571
Author(s):  
Luo Yi
Keyword(s):  
High Temperature ◽  
Chemical Composition ◽  
Impact Toughness ◽  
Thermal Fatigue ◽  
Fatigue Behavior ◽  
Fatigue Property ◽  
Eutectic Carbides ◽  
The Core ◽  
Thermal Fatigue Behavior ◽  
The Impact

4Cr5MoSiV1 steel, a widely used for hot work mould, contains Cr, Mo, V alloying elements that easily form carbides. The Micro-area chemical composition, microstructure, impact toughness and thermal fatigue behavior of 4Cr5MoSiV1 and 4Cr5MoSiV1H steels were investigated, the latter was carried on high temperature homogenizing and solution based on the former. The results showed that bulk eutectic carbides and elements segregation contained in the 4Cr5MoSiV1 steel reduced the impact toughness. But the impact toughness of the core of the mould steel block and thermal fatigue property of 4Cr5MoSiV1H steel were improved because the elements segregation and eutectic carbides was eliminated through the high temperature homogenizing and solution.

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