Rare earth elements chondrite-normalized patterns

Rare earth element patterns for basalt and chondrite, and the chondrite-normalized basalt REE pattern. Normalization removes the zigzag pattern due to differences in odd and even atomic number abundances. The europium (Eu) anomaly in the normalized pattern is due to incorporation of extra plagiodase. 

Figure 3, Chondrite-normalized rare earth element patterns of soapstone samples from quarries in the Mbe-marle-Nelson County regions of Virginia and in Crete. For the Albemarh-Nelson quarries f — the two lines give the range of 12 samples analyzed, and for the Crete samples (O — O) the two lines define the range of 19 samples. Two artifacts made of soapstone from the Albemarle-Nelson quarries are shown. One — M) is a pot from a habitation site in Cherokee County, NC and the other (A-- A) a pot from a habitation site near the quarry in Buckingham County, VA.

Figure 17 (a) Chondrite-normalized rare earth element patterns and (b) primitive-mantle normalized trace element... 

All values are on a coal basis. Data are exclusively from the US Geological Survey (USGS) except for estimated values in parenthesis which are based on USGS and literature data. Values in brackets are calculated from cerium and lanthanum data and assuming a chondrite normalized rare-earth-element distribution pattern. (ND — no data SD — standard deviation Max. — maximnm Num. = nnmber of samples). 

Figure 4 Chondrite-normalized rare earth element (REE) abundances in a suite of cogenetic iavas from the Eastern Gaiapagos Spreading Center (aiso shown in Figures 3 and 6). increasing abundances of REE and fhe size of the negative europium anomaiy from MORE fo andesite are consistent with evoiution of fhe suife primariiy by fractional crystallization. Concave-down patterns are an indication of their normal depleted chemical character (N-MORB).

Rare earth element concentrations in rocks are usi lly normalized to a common reference standard, which most commonly comprises the values for chondritic meteorites. Chondritic meteorites were chosen because they are thought to be relatively unfractionated samples of the solar system dating from, the original nucleosynthesis. However, the concentrations of the RZE in the solar system are very variable because of the different stabilities of the atomic nuclei. REE with even " atomic numbers are more stable (and therefore more abundant) than REE with odd atomic numbers, producing a zig-zag pattern bn a composition-abundance diagram (Figure 4.19). This pattern of abundances is also found in natural samples. 

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