cai calcium aluminum inclusions in botswana

VARIABLE AND EXTREME IRRADIATION CONDITIONS IN …

Abstract A search for short-lived {sup 10}Be in 21 calcium-aluminum-rich inclusions (CAIs) from Isheyevo, a rare CB/CH chondrite, showed that only 5 CAIs had {sup 10}B/{sup 11}B ratios higher than chondritic correlating with the elemental ratio {sup 9}Be/{sup 11}B

Humite Group (Mg,Fe)2x+1(SiO4)x(F,OH)2 where x = 1 …

Group X2YZ2O7 Melilite Occurrences Melilite Structure Melilite Chemistry Melilite generally occurs as Calcium Aluminum Inclusions (CAI) in silica and alkali poor igneous rocks. Barrel-shaped root-beer colored Melilite crystal with clear nepheline

The Effect of Jupiterʼs Formation on the Distribution of Refractory Elements and Inclusions …

The Effect of Jupiterʼs Formation on the Distribution of Refractory Elements and Inclusions in Meteorites Steven J. Desch1, Anusha Kalyaan1, and Conel M. O’D. Alexander2 1 School of Earth and Space Exploration, Arizona State University, P.O. Box 871404, Tempe, AZ 85287-1404, USA

Mineralogy, petrography, bulk chemical, iodine-xenon, …

Mineralogy, petrography, bulk chemical, iodine-xenon, and oxygen-isotopic compositions of dark inclusions in the reduced CV3 chondrite Efremovka

UNM Digital Repository - MICROSTRUCTURAL …

Refractory inclusions, calcium-aluminum-rich inclusions (CAIs) and amoeboid olivine aggregates (AOAs), of variable textures and mineralogies in CO3 chondrites have been investigated in detail using the focused ion beam (FIB) sample preparation technique coined with transmission electron microscopy (TEM) in order (1) to characterize the microstructures, compositions and textural …

MICROSTRUCTURAL ANALYSIS OF A COMPACT TYPE-A CALCIUM-ALUMINUM …

MICROSTRUCTURAL ANALYSIS OF A COMPACT TYPE-A CALCIUM-ALUMINUM RICH INCLUSION IN THE NORTHWEST AFRICA (NWA) 5028 CR2 CHONDRITE. T. Ramprasad1, P. Haene- cour2, T.J. Zega1,2.1Dept. of Material Science and Engineering, University of Arizona, Tucson, AZ 86719, USA.

Titanium isotopes and rare earth patterns in CAIs: Evidence for …

aluminum, silicon, calcium, titanium, and iron in each CAI, were obtained. These maps were of relatively low quality, as the slabs were not polished prior to analysis. After sampling for isotopic analysis, each CAI was reexam-ined by SEM-EDS and the major

The petrogenesis of type B1 Ca-Al-rich inclusions: The spinel …

Type B calcium-aluminum-rich inclusions (CAIs) were among the first igneous rocks produced within our solar system. These cm-sized spheres, which are found only in CV3 carbonaceous chondrites, have been the focus of much research (see a few

Morphology Control for Al2O3 Inclusion Without Ca …

Thus, Al 2 O 3 inclusions, which formed as soon as aluminum was added to molten steel, were reacted with dissolved [Mg] due to its higher activity than dissolved [Ca] in the melt, leading to the formation of MgO·Al 2 O 3 (MA) inclusions.[4, 51]

O ENRICHMENT IN CALCIUM–ALUMINUM-RICH INCLUSIONS …

Calcium–aluminum-rich inclusions (CAIs) from the metal-rich (CH/CB-like) carbonaceous chondrite Isheyevo are mineralogically pristine and show no evidence for postcrystallization alteration. Many of them are composed of very refractory minerals, such as 12O

Mg and Si isotopic fractionation patterns in types B1 and B2 CAIs: …

two type B2 calcium-aluminum-rich inclusions (CAIs) reveal differing but constant enrichments in heavy isotopes everywhere except ≤1000 lm from the CAI margins. There is no close correlation in the B1s or the B2s between isotopic composition and akermanite

Meteorite Chunk Contains Unexpected Evidence of Solid …

Others have looked for evidence of SiC in such calcium-aluminum-rich inclusions in meteorites using noble gases before, but Pravdivtseva’s team is the first to find it. “It was beautiful when all noble gases pointed to the same source of the anomalies — SiC,” she said.

METAMORPHOSED CALCIUM-ALUMINUM-RICH INCLUSIONS …

containing few calcium-aluminum-rich inclusions (CAIs) [4]. However, some CKs such as TNZ 057 have significant CAI contents [5]. We studied the min-eralogy and chemistry of CAIs in TNZ 057 to charac-terize their modifiion due to parent body 2 cut slabs

Primordial formation of major silies in a protoplanetary …

Abstract Understanding the spatial variability of initial 26 Al/ 27 Al in the solar system, i.e., (26 Al/ 27 Al) 0, is of prime importance to meteorite chronology, planetary heat production, and protoplanetary disc mixing dynamics.The (26 Al/ 27 Al) 0 of calcium-aluminum–rich inclusions (CAIs) in primitive meteorites (~5 × 10 −5) is frequently assumed to reflect the (26 Al/ 27 Al) 0 of

Lead isotopic ages of chondrules and calcium-aluminum …

6/9/2002· whereas the lead isotopic age of calcium-aluminum-rich inclusions (CAIs) in the CV chondrite Efremovka is 4567.2 +/- 0.6 Ma. This gives an interval of 2.5 +/- 1.2 million years (My) between formation of the CV CAIs and the CR chondrules and indies

This is a slice of carbonaceous chondrite, a rare type of …

Sep 21, 2012 - This is a slice of carbonaceous chondrite, a rare type of stony meteorite. It originates from the cold outer reaches of the asteroid belt. It is brittle compared to other meteorites and it consists of chondrules and inclusions eedded in a carbon-rich host matrix. The whispy white inclusions are called "CAI''s" (Calcium Aluminum Inclusions), which are some of the oldest

CV3 photos on Flickr | Flickr

Today we are going to focus on the structures called CAI (Calcium Aluminum Inclusions) also called Refractory Inclusions that are spectacular in this CC slice. They are not always so big and clear; this piece is the best I`ve ever had in my hand.

Researchers Find Presolar Grains in Unusual Inclusion …

Curious Marie is a notable example of an inclusion, or a chunk within a meteorite, called a calcium-aluminum-rich inclusion (CAI). These objects, some of the first to have condensed in the Solar

Earth and Planetary Science Letters

Recent whole-rock magnesium-isotopic data for calcium-aluminum-rich inclusions (CAIs) in chondrite meteorites indie that the primary nebular fractionation of alum inum from magnesium, probably by condensation, occurred within b20,000 years at 4.567 Ga.

Mineralogy, petrography, and oxygen isotopic …

Most UR CAIs, except for relict inclusions, are surrounded by single or multilayered Wark-Lovering rims composed of Sc-rich clinopyroxene, ±eringaite, Al-diopside, and ±forsterite. Most of UR CAIs in carbonaceous chondrites of petrologic types 2–3.0 are uniformly 16O-rich (Δ17O ∼ −23‰), except for one CH UR CAI, which is uniformly 16O-depleted (Δ 17O ∼ −5‰).

IN SITU TRACE ELEMENT ANALYSIS OF N ALLENDEA TYPE B1 CAI: …

IN SITU TRACE ELEMENT ANALYSIS OF N ALLENDEA TYPE B1 CAI: EK-459-5-1. C.R. Jeffcoat1, A. Kerekgyarto trace element composition of calcium, aluminum-rich inclusions (CAIs) provide constraints onphysical and chemical conditions andstages of

The formation of rims on calcium‐aluminum‐rich …

The petrologic and oxygen isotopic characteristics of calcium‐aluminum‐rich inclusions (CAIs) in CO chondrites were further constrained by studying CAIs from six primitive CO3.0‐3.1

Oxygen and magnesium isotope compositions of calcium-aluminum-rich inclusions …

1 10 (CAIs) from several Rumuruti (R) chondrites measured 20 17 30 resolvable excess of 40 -1-Oxygen and magnesium isotope compositions of calcium-aluminum-rich inclusions from Rumuruti (R) chondrites S. S. Rout1*, A. Bischoff1, K. Nagashima2, A. N. Krot2, G. R. Huss2, and K. Keil2

About us: PhD position in noble gas cosmochemistry - …

Pre-irradiation effects in Calcium-Aluminum-rich refractory inclusions Project: There is a well-known time gap between CAI formation and parent body accretion. The main objective of this study it to better quantify this time gap and to get some constraints about the physical conditions of CAI storage.

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EVALUATION AND CONTROL OF STEEL CLEANLINESS REVIEW

3 further explained by figure 1 [18], which shows the measured content of inclusions larger than 30 µm to drop from 1.61 ppm in a ladle to only 0.58ppm in the tundish. Thus, the tundish steel is cleaner, despite having a slightly higher total oxygen content and more

Forsterite-bearing Type B refractory inclusions from CV3 …

other varieties of igneous calcium-aluminum-rich inclusions (CAIs) (e.g., Type B, compact Type A, Type C), and also means that FoBs are ‘‘less refractory’’ than other CAIs owing to their enhanced magnesium and silicon relative to calcium, aluminum, and