The relationship between apparent equilibrium temperature and closure temperature with application to oxygen isotope geospeedometry

2014 ◽  
Vol 33 (2) ◽  
pp. 125-130 ◽  
Author(s):  
Huaiwei Ni
Keyword(s):  
Oxygen Isotope ◽  
Equilibrium Temperature ◽  
Closure Temperature ◽  
The Relationship ◽  
Apparent Equilibrium

scholarly journals Ore Genesis of the Takatori Tungsten–Quartz Vein Deposit, Japan: Chemical and Isotopic Evidence

Minerals ◽  
2021 ◽  
Vol 11 (7) ◽  
pp. 765
Author(s):  
Yuichi Morishita ◽  
Yoshiro Nishio
Keyword(s):  
Oxygen Isotope ◽  
Early Stage ◽  
Isotope Ratios ◽  
Equilibrium Temperature ◽  
Granitic Rocks ◽  
Granitic Magma ◽  
Lithium Isotope ◽  
Vein Deposit ◽  
Pressure Independent ◽  
Isotope Equilibrium

The Takatori hypothermal tin–tungsten vein deposit is composed of wolframite-bearing quartz veins with minor cassiterite, chalcopyrite, pyrite, and lithium-bearing muscovite and sericite. Several wolframite rims show replacement textures, which are assumed to form by iron replacement with manganese postdating the wolframite precipitation. Lithium isotope ratios (δ7Li) of Li-bearing muscovite from the Takatori veins range from −3.1‰ to −2.1‰, and such Li-bearing muscovites are proven to occur at the early stage of mineralization. Fine-grained sericite with lower Li content shows relatively higher δ7Li values, and might have precipitated after the main ore forming event. The maximum oxygen isotope equilibrium temperature of quartz–muscovite pairs is 460 °C, and it is inferred that the fluids might be in equilibrium with ilmenite series granitic rocks. Oxygen isotope ratios (δ18O) of the Takatori ore-forming fluid range from +10‰ to +8‰. The δ18O values of the fluid decreased with decreasing temperature probably because the fluid was mixed with surrounding pore water and meteoric water. The formation pressure for the Takatori deposit is calculated to be 160 MPa on the basis of the difference between the pressure-independent oxygen isotope equilibrium temperature and pressure-dependent homogenization fluid inclusions temperature. The ore-formation depth is calculated to be around 6 km. These lines of evidence suggest that a granitic magma beneath the deposit played a crucial role in the Takatori deposit formation.

On the relationship between the planetary radius and the equilibrium temperature for transiting exoplanets

2017 ◽  
Vol 26 (05) ◽  
pp. 1741012 ◽  
Author(s):  
Luigi Mancini
Keyword(s):  
Negative Correlation ◽  
Scaling Laws ◽  
Equilibrium Temperature ◽  
Least Squares Regression ◽  
Physical Processes ◽  
Transiting Planets ◽  
Astrophysical Objects ◽  
Best Fitting ◽  
The Relationship ◽  
Parent Star

Scaling laws have always played an important role in astronomy. They can give a general qualitative overview of common behaviors of many astrophysical objects, helping to understand the occurring physical processes. In the context of exoplanets, we study the possible correlation between (i) the planetary radius and the equilibrium temperature, [Formula: see text], and (ii) the planetary radius and the parent-star metallicity, [Formula: see text]. We considered a sample of transiting planets, for which their mass radius and equilibrium temperature are accurately determined. While we do not see any notable evidence of a correlation between [Formula: see text] and [Fe/H], the existence of a relationship between [Formula: see text] and [Formula: see text] is almost clear. We sub-divided our sample in different groups, based on their mass, and performed a least-squares regression of [Formula: see text] on [Formula: see text] for each sub-sample of planets. We found that the [Formula: see text] relation results very tight for two groups of intermediate-massive gas planets (i.e. for [Formula: see text] in the range between 0.5–1.0[Formula: see text][Formula: see text] and 1.0–1.5[Formula: see text][Formula: see text]) and that the slope of the best-fitting line gradually increases from the group of very massive to those of less massive planets, up to reverse in the Neptunian–Super-Earth regime, which has a negative correlation.

scholarly journals The relationship between climate and the intra-annual oxygen isotope patterns from pine trees: a case study along an elevation gradient on Corsica, France

2019 ◽  
Vol 76 (3) ◽  
Author(s):  
Sonja Szymczak ◽  
Achim Bräuning ◽  
Martin Häusser ◽  
Emilie Garel ◽  
Frédéric Huneau ◽  
...  
Keyword(s):  
Oxygen Isotope ◽  
Elevation Gradient ◽  
Pine Trees ◽  
The Relationship

scholarly journals The relationship between stress of plate-fin structures and emergency stop operation process in LNG heat exchanger

2021 ◽  
Vol 76 ◽  
pp. 77
Author(s):  
Hongqiang Ma ◽  
Shengxun Wang ◽  
Yue Xie ◽  
Xinmei Luo ◽  
Jianping Han
Keyword(s):  
Heat Exchanger ◽  
Temperature Difference ◽  
Equivalent Stress ◽  
Equilibrium Temperature ◽  
Equilibrium Pressure ◽  
Operation Process ◽  
Maximum Equivalent Stress ◽  
Emergency Stop ◽  
Last Stage ◽  
The Relationship

For insuring the safe operation of LNG heat exchanger in the Emergency Stop Operation Process (ESOP), a numerical method is proposed to investigate the stress of Plate-Fin Structures (PFS) in that. The relationship between stress of PFS and ESOP is analyzed in LNG heat exchanger. The results will be obtained that the maximum equivalent stress of PFS is greater at the initial stage of ESOP than that at the last stage when the HMR pressure is more than 5 MPa. The maximum equivalent stress increases with the equilibrium temperature when is greater than 180 K and reaches peak value at the last stage of ESOP. The maximum equivalent stress is larger at the last stage of ESOP than the other stage and increases with the equilibrium pressure. When the temperature difference is more than 5 K in the ESOP, the influence of that is obvious for the stress of PFS. In the ESOP, the equilibrium temperature and temperature difference should be controlled within 240 K and 5 K, respectively.

The rate of stationary wave of filtration combustion of gases in the same fields of temperature and concentration

2017 ◽  
Vol 12 (1) ◽  
pp. 27-32
Author(s):  
M.M. Kabilov ◽  
P.B. Sadriddinov ◽  
B.J. Gulboev ◽  
O.A. Kholov
Keyword(s):  
Wave Velocity ◽  
Stationary Wave ◽  
Equilibrium Temperature ◽  
Characteristic Size ◽  
Injection Rate ◽  
Temperature Fields ◽  
Inert Porous Medium ◽  
Combustion Of Gases ◽  
The Relationship ◽  
Combustion Of Hydrogen

Combustion of hydrogen-methane-air mixtures of gases in an inert porous medium is considered when the temperature fields of the medium end the concentration of the missing component of the mixture are similar. The relationship between the functions of temperature and concentration, as well as the equation for the numerical calculation of the temperature distribution, are obtained. Numerical calculations were made for different compositions of the hydrogen-methane-air mixture of gases and their effects on the wave velocity were determined. Dependences of the wave velocity, the equilibrium temperature, the characteristic size of the combustion zone, and the diffusion coefficient of the missing component on the gas injection rate are studied.

scholarly journals Experimental determination of the temperature dependence of oxygen-isotope fractionation between water and chitinous head capsules of chironomid larvae

2021 ◽  
Author(s):  
Alex Lombino ◽  
Tim Atkinson ◽  
Stephen J. Brooks ◽  
Darren R. Gröcke ◽  
Jonathan Holmes ◽  
...  
Keyword(s):  
Temperature Dependence ◽  
Oxygen Isotope ◽  
Oxygen Isotopes ◽  
Isotope Fractionation ◽  
Temperature Dependent ◽  
Oxygen Isotope Fractionation ◽  
Chironomid Larvae ◽  
Increasing Temperature ◽  
The Relationship

AbstractOxygen-isotope values of invertebrate cuticle preserved in lake sediments have been used in palaeoenvironmental reconstructions, generally with the assumption that fractionation of oxygen isotopes between cuticle and water ($$\upalpha_{\text{cuticle}-\text{H}_{2}\text{O}}$$ α cuticle - H 2 O ) is independent of temperature. We cultured chironomid larvae in the laboratory with labelled oxygen-isotope water and across a range of closely controlled temperatures from 5 to 25 °C in order to test the hypothesis that fractionation of oxygen isotopes between chironomid head capsules and water ($$\upalpha_{\text{chironomid}-\text{H}_{2}\text{O}}$$ α chironomid - H 2 O ) is independent of temperature. Results indicate that the hypothesis can be rejected, and that $$\upalpha_{\text{chironomid}-\text{H}_{2}\text{O}}$$ α chironomid - H 2 O decreases with increasing temperature. The scatter in the data suggests that further experiments are needed to verify the relationship. However, these results indicate that temperature-dependence of $$\upalpha_{\text{chironomid}-\text{H}_{2}\text{O}}$$ α chironomid - H 2 O should be considered when chironomid δ18O is used as a paleoenvironmental proxy, especially in cases where data from chironomids are combined with oxygen-isotope values from other materials for which fractionation is temperature dependent, such as calcite, in order to derive reconstructions of past water temperature.

scholarly journals Influence of climate change on carbon and oxygen isotope fractionation factors between glucose and α-cellulose of pine wood

2013 ◽  
Vol 40 (2) ◽  
pp. 145-152 ◽  
Author(s):  
Barbara Sensuła ◽  
Anna Pazdur
Keyword(s):  
Climate Change ◽  
Oxygen Isotope ◽  
Isotope Fractionation ◽  
Mean Value ◽  
Fractionation Factor ◽  
Oxygen Isotope Fractionation ◽  
Climate Signal ◽  
Carbon And Oxygen Isotope ◽  
The Relationship ◽  
Fractionation Factors

Abstract We present the first analysis of the influence of climate change on carbon and oxygen isotope fractionation factors for two saccharides (glucose and α-cellulose) of pine wood. The conifers grew in the Niepołomice Forest in Poland and the annual rings covered a time span from 1935 to 2000 AD. Glucose samples from acid hydrolysis of α-cellulose were extracted from annual tree rings. The carbon and oxygen isotope fractionation factors between glucose and α-cellulose were not stable over time. The mean value for the carbon isotope fractionation factors between glucose and α-cellulose was greater than unity. The mean value for the oxygen isotope fractionation factors between glucose and α-cellulose was lower than unity. We established, with respect to climate change, the significance of the interannual and intraannual variation in the carbon and oxygen isotope fractionation factors between both saccharides. We used moving interval correlation results for May of the previous year through September of the current year using a base length of 48 years. The relationship with summer temperature is the main climate signal in the carbon isotope fractionation factor between glucose and α-cellulose. The relationship with autumn sunshine is the main climate signal in the oxygen isotope fractionation factor between glucose and α-cellulose for the tree ring chronology.

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