UMATILLA COLUMBIA RIVER BASALT UMAT‐1

Abstract

A preliminary report is presented on a basalt reference sample, Umatilla Columbia River Basalt, UMAT‐1. Prepared in over 100 kg by the Columbia River Basalt Group, UMAT‐1 was, initially, tested for its homogeneity by two US laboratories for major, minor and several trace elements; mean values of these two laboratories are presented. More recent data on 50 elements by a French laboratory attest to the excellent homogeneity of the sample. UMAT‐1 is now available for further studies.