Analysis of rare-earth elements in fluid inclusions by inductively coupledplasma-mass spectrometry (ICP-MS)

Inductively coupled plasma-mass spectrometry (ICP-MS) is used to determine rare-earth elements abundances in fluid inclusions. Quartz separates from t he Lannigou and Yata Carlin-type gold deposits, southwestern China, were pr epared by the decrepitation-leach method. Leachates were analyzed by ICP-MS , using conventional sample introduction. The results demonstrate that the decrepitation-leach method, in combination with ICP-MS analysis of leachate s, is effective for REE determination. The chondrite-normalized REE pattern s of inclusion fluids for the Lannigou and Yata samples associated with gol d mineralization are characterized by light rare-earth elements (LREE) enri chment, with a weak negative Ce anomaly and a positive or negative Eu anoma ly, whereas the pattern for the Lannigou sample associated with late gold m ineralization (quartz-calcite stage) is characterized by LREE enrichment re lative to HREE, with negative Ce and Eu anomalies.