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The Istituto di Geoscienze e Georisorse (IGG), on behalf and with the support of the International Atomic Energy Agency (IAEA), prepared eight geological materials (three natural waters and five rocks and minerals), intended for a blind interlaboratory comparison of measurements of boron isotopic composition and concentration. The materials were distributed to twenty seven laboratories ‐ virtually all those performing geochemical boron isotope analyses in the world ‐which agreed to participate in the intercomparison exercise. Only fifteen laboratories, however, ultimately submitted the isotopic and/or concentration results they obtained on the intercomparison materials. The results demonstrate that interlaboratory reproducibility is not well reflected by the precision values reported by the individual laboratories and this observation holds true for both boron concentration and isotopic composition. The reasons for the discrepancies include fractionations due to the chemical matrix of materials, relative shift of the zero position on the δ11B scale and a lack of well characterized materials for calibrating absolute boron content measurements. The intercomparison materials are now available at the IAEA (solid materials) and IGG (waters) for future distribution.

A modified concentric glass nebulizer interface for capillary electrophoresis (CE) and inductively coupled plasma mass spectrometry is described. A conductive liquid coaxial sheath in the nebulizer was used as the return ground for the CE capillary. The variable position of the CE capillary in the nebulizer interface made a compromise between separation resolution and signal intensity possible. Negative reservoir pressure was applied to counterbalance nebulizer suction to the CE capillary and restore resolution. Metallothionein and ferritin were evaluated to characterize the interface. Metallothionein isoforms and ferritin were separated and their metal contents identified. Detection limits achieved for 57Fe and 114Cd in ferritin were 184 and 4.0 fg, respectively, for 74 nL injections.Capillary electrophoresis (CE) is applied for the separation of small inorganic1-7 and organic ions,89 small drug molecules,10 peptides,11-14 and proteins.15-18 CE generally offers better resolution and separation efficiency than chromatographic techniques, and the separation is usually faster and requires much less sample (a few nanoliters).Since Smith et al.19 first developed capillary electrophoresismass spectrometry (CE-MS), CE-MS has been extended to almost all kinds of CE techniques.20-23 In most cases, electrospray(1) Jandik, P.;

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The authors thank the Environmental Protection Agency for partial support of this work through the Interagency Energy/Environment Program (EPA-IGA-D5-E684). The specification of commercial products does not imply endorsement by the National Bureau of Standards.

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Major-element compositions (Cl", SO 2 .", Ca 2+ , Mg 2 + , Li + , K + , Na + , Sr 2+ ) of interstitial waters obtained from sediment cores along the ODP Leg 110 transect across the Northern Barbados accretionary prism have shown that a complex set of geochemical processes are of importance in this area. In the volcanic ash-rich Pleistocene-Pliocene sedi ments, alteration reactions involving volcanic ash lead to depletions of Mg 2+ and K + . This process is confirmed by the much lower than contemporaneous seawater values of the 87 Sr/ 86 Sr ratios of dissolved strontium. In the deeper sedi ments recovered below the zone of decollement (Sites 671 and 672) large increases in Ca 2+ and gradual decreases in Mg 2 + , Na + , and 6 18 0 (H 2 0) indicate a potential contribution to the interstitial water chemistry by exchange with un derlying basement rocks. This process has been hard to confirm because the drill holes were terminated well short of reaching basement. However, the concentration gradient pattern is consistent with observations in a large number of DSDP drill holes. Finally, but most importantly, low Cl" concentrations in the decollement zone and underlying sand layers, as well as in fault zones at Sites 673 and 674, indicate dilution of interstitial waters. The potential origins of the low Cl" concentrations are discussed, though we are not able to distinguish any mechanism in particular. Our evidence supports the concept of water migration along the decollement and through the underlying sandstones as well as along recent fault zones in the accretionary complex. Interstitial water concentration depth profiles are affected by faulting, thrusting, and overturn processes in the accretionary prism. These processes have caused a diminished diffusive ex change with the overlying ocean, thus explaining increased depletions in Mg 2+ and SO 2 " in sites farther onto the accre tionary prism.