Mineral chemistry and genetic relations among H-group chondrites

1981 ◽  
Vol 374 (1757) ◽  
pp. 159-178 ◽  
Keyword(s):  
Mineral Chemistry ◽  
Solidification Structure ◽  
Liquid Fractionation ◽  
Type 3 ◽  
Lines Of Evidence

The chondrites Bremervorde and Tieschitz (both H3), Beaver Creek, Menow, Monroe and Quenggouk (all H4), Allegan and Ambapur Nagla (both H5), and Butsura and Kernouve (both H6) were studied. Ca-poor pyroxenes almost invariably show enrichment in Mg relative to coexisting olivines; this was established in Tieschitz chondrules and in Bremervorde by crystal-liquid equilibria. In each chondrite, Ca-poor pyroxenes typically have less than 2 mol % wollastonite. In petrologic types 3 and 4, chondrule mesostases frequently show enrichment in normative diopside, which occurs as a resolvable modal phase in the type 6 chondrites. Partition of Ca between the two pyroxenes was initiated by crystal-liquid fractionation. Various chemical inhomogeneities may be traced from type 3 meteorites to those of type 6. Polycrystalline taenite occurs in Tieschitz, Bremervörde, Menow, Quenggouk and Butsura; it is rarely present in Kernouve. This textural form of taenite is interpreted as a relict solidification structure produced from a quenched liquid, which must have cooled rapidly to below about 700 °C. We argue that equilibration of the H-group chondrites took place during cooling, mainly from about 700 °C, which is compatible with several lines of evidence. If metamorphism is defined as change induced by an increase in temperature, then in the H-group chondrites studied we recognize it only in transient reheating probably produced by shock.

A New Look at the Galim (a) and Galim (b) Meteorites

1988 ◽  
Vol 52 (367) ◽  
pp. 519-525 ◽  
Author(s):  
Mireille Christophe Michel-Lévy ◽  
Michèle Bourot-Denise
Keyword(s):  
Mineral Chemistry ◽  
The Other ◽  
Reducing Conditions ◽  
Enstatite Chondrite ◽  
Type 3 ◽  
New Look

AbstractSmall stones were recovered from a meteorite shower observed in Cameroon on November 13, 1952. The majority are LL6 specimens, Galim (a), but one is a chondrule-rich enstatite chondrite, Galim (b). Petrology and mineral chemistry were determined on polished sections of both types. Galim (a) has undergone multiple brecciation. During the first, chromite apparently recrystallized in healed fractures under more reducing conditions than those which prevailed when the silicates recrystallized. Galim (b) shows some features of petrologic type 3 but differs considerably from the other unequilibrated E chondrites. It is suggested that Galim (a) and Galim (b) belong to the same meteorite shower.

scholarly journals Mg-Phengite in Carbonate Rock Syngenetically Formed from Hydrothermal Fluid: Micro-Textural Evidence and Mineral Chemistry

Minerals ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 668
Author(s):  
Chaewon Park ◽  
Namsoo Kim ◽  
Sung-Ja Choi ◽  
Yungoo Song
Keyword(s):  
Hydrothermal Fluid ◽  
Fine Sand ◽  
Structural Formula ◽  
Mineral Chemistry ◽  
Crystalline Dolomite ◽  
Polycrystalline Aggregates ◽  
Form Type ◽  
Clastic Sedimentary ◽  
End Members ◽  
Type 3

Phengite series is a dioctahedral solid solution between two end-members of muscovite [K1[Al2]VI[Al1,Si3]IVO10(OH)2] and celadonite [K1[(Fe3+,Al)1,(Mg,Fe2+)1]VI[Si4]IVO10(OH)2], which have a hetero-valent substitution of AlVIAlIV ↔ (Mg, Fe)VISiIV. In this study, we report a hydrothermal-originated authigenic Mg-phengite-series mineral, which occurred as polycrystalline aggregates (Type 1), pore-fillings (Type 2) and well-crystallized lath form (Type 3) from the Haengmae Formation, a dolomite–pebble-bearing fine sand-sized dolostone, in South Korea. Based on micro-textural observation, three types of Mg-phengite are associated with crystalline dolomite, and are followed by calcite precipitation as pore-filling, indicating that these should be formed by the influx of a Mg-rich hydrothermal fluid after the deposition of some clastic sediments and before calcite-filling. The structural formula based on O10(OH)2 shows that the number of Mg atoms per formula unit (apfu) of Mg-phengite ranges from 0.00 to 0.70 with no Fe, which is relatively high, compared with the previously reported metamorphic phengites. In REEs mineral chemistry, the Mg-phengites are characterized by the enrichment of REEs and by the particular enrichment of LREEs in the polycrystalline aggregates of Mg-phengite. It strongly suggests that the Mg-phengite should be formed by the infiltration of the highly evolved Mg- and REEs-enriched hydrothermal fluid into the clastic sedimentary rock (Haengmae Formation) as a strata-bound form, syngenetically or during early diagenesis.

Fluency: A trigger of familiarity for relational representations?

2019 ◽  
Vol 42 ◽  
Author(s):  
Talya Sadeh
Keyword(s):  
Memory Model ◽  
Lines Of Evidence

Abstract According to Bastin et al.’s integrative memory model, familiarity may be attributed to both entity representations and relational representations. However, the model does not specify what triggers familiarity for relational representations. I argue that fluency is a key player in the attribution of familiarity regardless of the type of representation. Two lines of evidence are reviewed in support of my claim.

Scanning Electron Microscopy of the Red Pulp of the Spleen

1971 ◽  
Vol 29 ◽  
pp. 496-497
Author(s):  
Masayuki Miyoshi
Keyword(s):  
Electron Microscope ◽  
Ringer Solution ◽  
Conclusive Evidence ◽  
Sinus Wall ◽  
Transmission Electron ◽  
Type 3 ◽  
Cytoplasmic Processes ◽  
Splenic Red Pulp ◽  
Scanning Electron ◽  
Red Pulp

In spite of various attempts, conclusive evidence to explain blood passage in the splenic red pulp does not seem to have been presented. Scanning electron microscope (SEM) observations on the rabbit spleen, originally performed by us, revealed that the sinus was lined by a perforated lattice composed of longitudinally extended rod cells and transverse cytoplasmic processes, and that perforations in the lattice were continuous to the spaces among the stellate reticulum cells of the cord. In the present study the observation was extended to the dog and rat spleens, in which the cord is more developed than in the rabbit in order to clarify the possible differences in the fine structure of the sinus wall. An attempt was also made to examine the development and distribution of macrophage in the blood passage of the red pulp.Spleens were washed and fixed by perfusion with Ringer solution and then with buffered glutaraldehyde. Small tissue cubes were dehydrated with acetone, dried in air and heated with gold. Observations were made by a JEOL SEM Type-3. One air dried tissue cube was cut into small pieces and post fixed with buffered OsO4 for examination under the transmission electron microscope (TEM).

Familial hyperlipoproteinemia type 3

1969 ◽  
Vol 100 (4) ◽  
pp. 401-406 ◽  
Author(s):  
R. Fleischmajer
Keyword(s):  
Type 3

Ten years’ experience of enzyme infusion therapy of Norrbottnian (type 3) Gaucher disease

2006 ◽  
Vol 95 (3) ◽  
pp. 312-317 ◽  
Author(s):  
Anders Erikson ◽  
Håkan Forsberg ◽  
Magnus Nilsson ◽  
Marianne Åström ◽  
Jan-Eric Månsson
Keyword(s):  
Gaucher Disease ◽  
Infusion Therapy ◽  
Type 3 ◽  
Enzyme Infusion

A Novel Mutation Glyl672→Arg in Type 2A and a Homozygous Mutation in Type 2B von Willebrand Disease

1996 ◽  
Vol 76 (02) ◽  
pp. 253-257 ◽  
Author(s):  
Takeshi Hagiwara ◽  
Hiroshi Inaba ◽  
Shinichi Yoshida ◽  
Keiko Nagaizumi ◽  
Morio Arai ◽  
...  
Keyword(s):  
Missense Mutation ◽  
Novel Mutation ◽  
Point Mutations ◽  
Japanese Patients ◽  
Von Willebrand Disease ◽  
Homozygous Mutation ◽  
Missense Mutations ◽  
Reaction Products ◽  
Type 3 ◽  
Von Willebrand

SummaryGenetic materials from 16 unrelated Japanese patients with von Willebrand disease (vWD) were analyzed for mutations. Exon 28 of the von Willebrand factor (vWF) gene, where point mutations have been found most frequent, was screened by various restriction-enzyme analyses. Six patients were observed to have abnormal restriction patterns. By sequence analyses of the polymerase chain-reaction products, we identified a homozygous R1308C missense mutation in a patient with type 2B vWD; R1597W, R1597Q, G1609R and G1672R missense mutations in five patients with type 2A; and a G1659ter nonsense mutation in a patient with type 3 vWD. The G1672R was a novel missense mutation of the carboxyl-terminal end of the A2 domain. In addition, we detected an A/C polymorphism at nucleotide 4915 with HaeIII. There was no particular linkage disequilibrium of the A/C polymorphism, either with the G/A polymorphism at nucleotide 4391 detected with Hphl or with the C/T at 4891 detected with BstEll.

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