Comparison of the Rainy Ridge analcime phonolite sill and the Crowsnest volcanics, Alberta, Canada

1993 ◽  
Vol 30 (8) ◽  
pp. 1644-1649 ◽  
Author(s):  
R. J. Goble ◽  
S. B. Treves ◽  
A. M. Ghazi
Keyword(s):  
Chemical Composition ◽  
Genetic Relationship ◽  
Shallow Depth ◽  
Apparent Difference ◽  
The North ◽  
Hydrous Phase ◽  
Hydrous Melt ◽  
Rapid Transport ◽  
Opaque Minerals ◽  
Hydrous Magma

A 5–7 m thick analcime phonolite sill occurs in the middle of the Proterozoic Gateway Formation in southwest Alberta. The sill consists of sanidine, aegirine–augite, magnesian hastingsite, melanite with hydrogrossular rims, titanite, and minor biotite, apatite, and opaque minerals. Mineralogical and chemical similarities to the analcime-rich phases of the Cretaceous Crowsnest Formation found some 20 km to the north suggest a genetic relationship. Major differences are the presence of amphibole and hydrogrossular, minerals not reported in the Crowsnest Formation. The presence of amphibole as a primary hydrous phase in the Rainy Ridge sill indicates crystallization from a hydrous magma. Microprobe studies indicate a progressive enrichment of sodium in amphiboles and pyroxenes. An apparent difference in chemical composition and alteration behavior of primary analcime phenocrysts and groundmass analcime is interpreted to reflect crystallization of analcime from a hydrous melt at depth, followed by rapid transport to a shallow depth, and crystallization of the groundmass analcime and hydrogrossular rims.

Underbalanced Drilling with Coiled Tubing: A Case Study on the Alaskan North Slope, Which Proves the Benefits of Drilling a Straight Hole

2021 ◽  
Author(s):  
Antoni Miszewski ◽  
Adam Miszewski ◽  
Richard Stevens ◽  
Matteo Gemignani
Keyword(s):  
Relative Effectiveness ◽  
Shallow Depth ◽  
North Slope ◽  
Coiled Tubing ◽  
The North ◽  
North Slope Of Alaska ◽  
Minimum Requirements ◽  
Bottom Hole Assembly ◽  
Alaskan North Slope ◽  
Future Work

Abstract A set of 5 wells were to be drilled with directional Coiled Tubing Drilling (CTD) on the North Slope of Alaska. The particular challenges of these wells were the fact that the desired laterals were targeted to be at least 6000ft long, at a shallow depth. Almost twice the length of laterals that are regularly drilled at deeper depths. The shallow depth meant that 2 of the 5 wells involved a casing exit through 3 casings which had never been attempted before. After drilling, the wells were completed with a slotted liner, run on coiled tubing. This required a very smooth and straight wellbore so that the liner could be run as far as the lateral had been drilled. Various methods were considered to increase lateral reach, including, running an extended reach tool, using friction reducer, increasing the coiled tubing size and using a drilling Bottom Hole Assembly (BHA) that could drill a very straight well path. All of these options were modelled with tubing forces software, and their relative effectiveness was evaluated. The drilling field results easily exceeded the minimum requirements for success. This project demonstrated record breaking lateral lengths, a record length of liner run on coiled tubing in a single run, and a triple casing exit. The data gained from this project can be used to fine-tune the modelling for future work of a similar nature.

scholarly journals On the competition among aerosol number, size and composition in predicting CCN variability: a multi-annual field study in an urbanized desert

2015 ◽  
Vol 15 (12) ◽  
pp. 6943-6958 ◽  
Author(s):  
E. Crosbie ◽  
J.-S. Youn ◽  
B. Balch ◽  
A. Wonaschütz ◽  
T. Shingler ◽  
...  
Keyword(s):  
Chemical Composition ◽  
Size Distribution ◽  
North American ◽  
Monsoon Season ◽  
Aerosol Size Distribution ◽  
North American Monsoon ◽  
Aerosol Composition ◽  
Data Set ◽  
The North ◽  
Concentration Changes

Abstract. A 2-year data set of measured CCN (cloud condensation nuclei) concentrations at 0.2 % supersaturation is combined with aerosol size distribution and aerosol composition data to probe the effects of aerosol number concentrations, size distribution and composition on CCN patterns. Data were collected over a period of 2 years (2012–2014) in central Tucson, Arizona: a significant urban area surrounded by a sparsely populated desert. Average CCN concentrations are typically lowest in spring (233 cm−3), highest in winter (430 cm−3) and have a secondary peak during the North American monsoon season (July to September; 372 cm−3). There is significant variability outside of seasonal patterns, with extreme concentrations (1 and 99 % levels) ranging from 56 to 1945 cm−3 as measured during the winter, the season with highest variability. Modeled CCN concentrations based on fixed chemical composition achieve better closure in winter, with size and number alone able to predict 82 % of the variance in CCN concentration. Changes in aerosol chemical composition are typically aligned with changes in size and aerosol number, such that hygroscopicity can be parameterized even though it is still variable. In summer, models based on fixed chemical composition explain at best only 41 % (pre-monsoon) and 36 % (monsoon) of the variance. This is attributed to the effects of secondary organic aerosol (SOA) production, the competition between new particle formation and condensational growth, the complex interaction of meteorology, regional and local emissions and multi-phase chemistry during the North American monsoon. Chemical composition is found to be an important factor for improving predictability in spring and on longer timescales in winter. Parameterized models typically exhibit improved predictive skill when there are strong relationships between CCN concentrations and the prevailing meteorology and dominant aerosol physicochemical processes, suggesting that similar findings could be possible in other locations with comparable climates and geography.

scholarly journals MINERAL CHEMISTRY AND GEOCHEMISTRY OF HYPERSTHENE-BEARING DIORITE FROM ERUSU AKOKO, SOUTHWESTERN NIGERIA

2020 ◽  
Vol 4 (1) ◽  
pp. 13-18
Author(s):  
E. J. Oziegbe ◽  
V. O. Olarewaju ◽  
O. O. Ocan
Keyword(s):  
Chemical Composition ◽  
Chemical Properties ◽  
Mineral Chemistry ◽  
Accessory Mineral ◽  
Southwestern Nigeria ◽  
Hydrous Minerals ◽  
Icp Ms ◽  
Composition Of Minerals ◽  
Textural Relationship ◽  
Opaque Minerals

Samples of mafic intrusive rock were analyzed for their mineralogical and chemical properties. The textural relationship was studied using the petrographic microscope, elemental composition of minerals was determined using the Electron Microprobe and the whole rock chemical analysis was done using the XRF and ICP-MS. The following minerals were observed in order of abundance; pyroxene, amphibole, plagioclase, biotite, opaque minerals, quartz and chlorite, with apatite and zircon occurring as accessory mineral. Two types of pyroxenes were observed; orthopyroxene (hypersthene) and clinopyroxene. Texturally, amphiboles have inclusions of plagioclase and pyroxene. The plagioclase has undergone sericitization. The chemical composition of the pyroxene is En51.95Fs44.53Wo3.52, biotite has Fe/(Fe+Mg):0.42, Mg/(Fe+Mg):0.59, and plagioclase is Ab63.5An34.55Or1.95. Whole rock chemistry shows a chemical composition; SiO2: 45.15 %, Al2O3: 14.04 %, Fe2O3: 16.01 %, MgO: 5.65 %, CaO: 7.58 % and TiO2: 3.59 %. There is an enrichment of LREE and a depletion of HREE. Based on the minerals, mineral chemistry and the geochemistry of the studied rock, the rock is mafic and hydrous minerals formed by hydration recrystallization of pyroxene. The rock has extensively retrogressed but has not been affected by any form of deformation.

On the difference of aerosol hygroscopicity between high and low RH environment in the North China Plain

2021 ◽  
Author(s):  
Jingnan Shi ◽  
Juan Hong ◽  
Nan Ma ◽  
Qingwei Luo ◽  
Hanbing Xu ◽  
...  
Keyword(s):  
Chemical Composition ◽  
North China Plain ◽  
North China ◽  
Experimental Period ◽  
Formation Mechanisms ◽  
Large Contribution ◽  
The North ◽  
The North China Plain ◽  
The Difference ◽  
Aerosol Hygroscopicity

<p>Simultaneous measurements of aerosol hygroscopicity and chemical composition were performed at a suburban site in the North China Plain in winter 2018 using a self-assembled hygroscopic tandem differential mobility analyzer (H-TDMA) and a capture-vaporizer time-of-flight aerosol chemical speciation monitor (CV-ToF-ACSM), respectively. During the experimental period, aerosol particles usually show an external mixture in terms of hygroscopicity, with a less hygroscopic particles mode (LH) and a more hygroscopic mode (MH). The average ensemble mean hygroscopicity parameter (κ<sub>mean</sub>) are 0.16, 0.18, 0.16, and 0.15 for 60, 100, 150, and 200 nm particles, respectively. Two episodes with different RH/T conditions and secondary aerosol formations are distinguished. Higher aerosol hygroscopicity is observed for all measured sizes in the high RH episode (HRH) than in the low RH episode (LRH). In LRH, κ decreases as the particle size increases, which may be explained by the large contribution of non- or less-hygroscopic primary compounds in large particles due to the enhanced domestic heating emissions at low temperature. The number fraction of LH mode at 200 nm even exceeds 50%. Closure analysis is carried out between the HTDMA-measured κ and the ACSM-derived hygroscopicity using different approximations for the hygroscopic parameters of organic compounds (κ<sub>org</sub>). The results indicate that κ<sub>org</sub> is less sensitive towards the variation of its oxidation level under HRH conditions but has a stronger O: C-dependency under LRH conditions. The difference in the chemical composition and their corresponding physical properties under different RH/T conditions reflects potentially different formation mechanisms of secondary organic aerosols at those two distinct episodes.</p>

Middle Bronze Age Long Distance Exchange through Europe and Beyond

2020 ◽  
Vol 26 (2) ◽  
pp. 266-274
Author(s):  
Flemming Kaul
Keyword(s):  
Chemical Composition ◽  
Bronze Age ◽  
Glass Beads ◽  
The South ◽  
Long Distance ◽  
Blue Glass ◽  
The North ◽  
Southern Scandinavia ◽  
Middle Bronze Age ◽  
The Mediterranean

Abstract The introduction of the folding stool and the single-edged razor into Southern Scandinavia, as well as the testimony of chariot use during the Nordic Bronze Age Period II (1500-1300 BC), give evidence of the transfer of ideas from the Mediterranean to the North. Recent analyses of the chemical composition of blue glass beads from well-dated Danish Bronze Age burials have revealed evidence for the opening of long distance exchange routes around 1400 BC between Egypt, Mesopotamia and South Scandinavia. When including comparative material from glass workshops in Egypt and finds of glass from Mesopotamia, it becomes clear that glass from those distant lands reached Scandinavia. The routes of exchange can be traced through Europe based on finds of amber from the North and glass from the South.

On the genetic relationship and clasaification of Meteorites

1916 ◽  
Vol 18 (83) ◽  
pp. 26-44 ◽  
Author(s):  
G. T. Prior
Keyword(s):  
Chemical Composition ◽  
Genetic Relationship ◽  
Close Similarity ◽  
Chemical Compositions ◽  
Nickel Iron

In a previous paper attention was drawn to the close similarity in mineral and chemical composition of chondritic meteoric stones. In the case of about forty chondrites it was shown that, apart from variations in the amount of nickel-iron, not only are the constituent minerals present in very similar amounts, but their chemical compositions vary to no very great extent. In that paper sufficient importance was not attached to the variations in the amount of nickel-iron.

Reactive bulk assimilation: A model for crust-mantle mixing in silicic magmas

Geology ◽  
2005 ◽  
Vol 33 (8) ◽  
pp. 681-684 ◽  
Author(s):  
James S. Beard ◽  
Paul C. Ragland ◽  
Maria Luisa Crawford
Keyword(s):  
Dehydration Melting ◽  
Crustal Rocks ◽  
Host Magma ◽  
Ti Oxides ◽  
Energy Penalty ◽  
Magma Crystallization ◽  
Hydrous Melt ◽  
Silicic Magmas ◽  
Solid Form ◽  
Hydrous Magma

Abstract Bulk assimilation of small (millimeters to ∼1 km) fragments of crust—driven and (ultimately) masked by reactions during xenolith melting and magma crystallization—is an important mechanism for crust-mantle mixing. Xenoliths containing mica or amphibole undergo dehydration melting when incorporated into a host magma, yielding mainly plagioclase, pyroxene, Fe-Ti oxides, and hydrous melt. The xenolith is physically compromised by partial melting and begins to disintegrate; xenolithic melt and crystals are mixed into the host magma. Xenocrystic zircon is liberated at this stage. The cryptic character of assimilation is greatly enhanced in any hydrous magma by hydration crystallization reactions (the reverse of dehydration melting). All pyroxenes and oxides (phenocrysts, xenocrysts, or crystals having a hybrid signature) will be subject to these reactions, producing feldspars, amphiboles, and micas that incorporate material from several sources, a particularly effective mixing mechanism. Implicit in the model is a reduced energy penalty for bulk assimilation—much of the assimilant remains in solid form—compared to melt-assimilation models. A large role for bulk assimilation supports stoping as a credible mechanism for the ascent of magmas. While the assimilation of low-density crust and concomitant fractionation provide the isostatic impetus for ascent, the wholesale incorporation and processing of crustal rocks in the magma chamber helps create the room for ascent.

Phenotypic and genotypic signature of saponin chemical composition in Chinese wild soybean (Glycine soja): revealing genetic diversity, geographical variation and dispersal history of the species

2018 ◽  
Vol 69 (11) ◽  
pp. 1126
Author(s):  
Yuya Takahashi ◽  
Xiang-Hua Li ◽  
Chigen Tsukamoto ◽  
Ke-Jing Wang
Keyword(s):  
Genetic Diversity ◽  
Chemical Composition ◽  
Genetic Structure ◽  
Southern China ◽  
Glycine Soja ◽  
Wild Soybean ◽  
Ice Age ◽  
High Genetic Diversity ◽  
The North ◽  
Or Genes

Saponin chemical composition was phenotyped and genotyped, and saponin composition-based geographical genetic diversity and differentiation were evaluated in Chinese wild soybean (Glycine soja Sieb. & Zucc.). Thirty-two phenotypes and 34 genotypes were confirmed from 3805 wild soybean accessions. Eleven phenotypes (AaαK, AaαIK, AaαIJK, AaBcEαJ, AaBcαK, AbEαIJ, AbαK, AbαIK, AbαIJK, AbβHAb and Aβ0) were newly detected. Four genes had frequencies: Sg-1a 78.8% and Sg-1b 21.0% at the Sg-1 locus; Sg-4 30.7% and Sg-6e 13.7% at their respective loci. The north-eastern and southern populations showed high genetic diversity; the Northeast region contained more novel variants (AuAe, A0, A0Bc, αH, αI αJ, αK, and AbβHAb), and the southern populations contained high frequencies of the Sg-4 gene. Gene differentiation (Fst) analysis suggested that Sg-4 and four group-α saponin alleles or genes (Sg-6e, Sg-6h, Sg-6i, Sg-6j) were important factors influencing the genetic structure and differentiation in Chinese wild soybeans. Geographical differentiation was characterised mainly by latitudinal differences, with two primary groups (north and south) based on saponin genes. Chinese wild soybean accessions differed from Japanese and South Korean ones in genetic structure based on saponin composition, the latter two being likely to have spread from southern China in the glacial stages during the last Ice Age.

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