Table 1 Carbon, N, Si, Al, and Ti isotopic compositions of type X SiC grains in Murchison.

Uncertainties are 1σ. A, agglomerate-like morphology; S, single grains. Four grains had too low Ti concentrations so that their Ti isotope ratios could not be determined.

GrainSize
(μm)
Morphology12C/13C14N/15Nδ29Si*
(‰)
δ30Si
(‰)
26Al/27Al
(×1000)
δ46Ti
(‰)
δ47Ti
(‰)
δ49Ti
(‰)
δ50Ti
(‰)
V/Ti
M1-A3-G3201.6 × 2.8A224 ± 251 ± 1−273 ± 5−448 ± 8392 ± 339 ± 64113 ± 93400 ± 19228 ± 100.311
M1-A7-G9611.1 × 1.0A164 ± 2113 ± 4−399 ± 5−544 ± 8268 ± 140 ± 47−6 ± 70350 ± 18−8 ± 80.094
M1-A8-G1371.9 × 1.3A149 ± 265 ± 2−286 ± 6−445 ± 17350 ± 1−17 ± 72−84 ± 86402 ± 19206 ± 100.116
M1-A9-G9211.3 × 1.2S211 ± 354 ± 1−316 ± 8−464 ± 12230 ± 1−4 ± 89−55 ± 103528 ± 21220 ± 120.054
M2-A1-G4210.6 × 0.6S145 ± 4126 ± 3−237 ± 7−375 ± 15153 ± 245 ± 290 ± 32508 ± 21191 ± 110.273
M2-A1-G6742.5 × 2.6A120 ± 387 ± 1−210 ± 6−290 ± 8303 ± 1−8 ± 17−23 ± 22304 ± 17198 ± 100.139
M2-A1-G9042.6 × 2.7S100 ± 370 ± 1−168 ± 6−341 ± 12277 ± 115 ± 3713 ± 22261 ± 29186 ± 290.047
M2-A1-G9742.1 × 2.5A139 ± 4116 ± 2−222 ± 6−343 ± 10203 ± 1−2 ± 27−6 ± 12158 ± 15188 ± 100.017
M2-A2-G3730.9 × 0.9S149 ± 6−183 ± 17−186 ± 2539 ± 1−3 ± 5225 ± 76115 ± 15192 ± 100.130
M2-A2-G10361.1 × 1.2S202 ± 7−404 ± 12−572 ± 15209 ± 171 ± 8523 ± 25417 ± 3598 ± 320.091
M2-A3-G1203.7 × 3.7A82 ± 1−155 ± 6−240 ± 11306 ± 123 ± 6979 ± 93268 ± 17234 ± 100.169
M2-A3-G10101.0 × 0.6S318 ± 12−291 ± 14−475 ± 11199 ± 141 ± 5555 ± 80685 ± 24119 ± 120.109
M2-A3-G14671.0 × 1.1S105 ± 2−153 ± 7−265 ± 15225 ± 1101 ± 7863 ± 9794 ± 15127 ± 100.092
M3-G5011.0 × 0.9S86 ± 238 ± 1−330 ± 15−480 ± 15126 ± 181 ± 13810 ± 149603 ± 21316 ± 110.067
M3-G6911.6 × 1.6A36 ± 134 ± 1−216 ± 8−230 ± 8127 ± 1−19 ± 43−36 ± 44114 ± 15−31 ± 80.044
M3-G13431.2 × 1.8S52 ± 1120 ± 4−106 ± 7−161 ± 78.0 ± 0.182 ± 56116 ± 83126 ± 41120 ± 410.049
M2-A3-G430.8 × 0.8S81 ± 1−380 ± 7−500 ± 14367 ± 2
M2-A3-G16830.7 × 0.8S54 ± 1−335 ± 6−430 ± 14307 ± 1
M2-A4-G14330.8 × 0.8S104 ± 6−393 ± 19−424 ± 29200 ± 1
M2-A5-G4120.9 × 1.2S67 ± 222 ± 1−237 ± 7−375 ± 15

*δ notation is defined as δiA = [(iA/jA)grain/(iA/jA)std − 1] × 1000, where A denotes an element, i denotes an isotope of this element, and j denotes the normalization isotope, and (iA/jA)grain and (iA/jA)std represent the corresponding isotope ratios measured in a sample and the standard, respectively.