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We conducted a reconnaissance probe for Ir using laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) in mid-Ediacaran strata of SW Laurentia, previously proposed to be coeval with strata in South Australia that host the Acraman meteorite ejecta horizon. The advantages of rapid sample preparation and precise knowledge of textural context afforded by LA-ICP-MS, relative to more accurate whole-rock methods, are offset by its high limit of detection for a single spot analysis (range: 4–10 ppb), which has generally discouraged its application to Ir in meteorite ejecta horizons. A key exception showed that in an unusually enriched Archean spherule horizon in western Australia, Ir was concentrated in “nuggets” that averaged seven times the whole-rock concentration in 10% of the spot analyses and was generally cospatial with Fe oxides. If a similar distribution applies to more typical ejecta horizons, then the high signal-to-noise ratio of nuggets could be exploited to significantly improve whole-rock analytical error, which is not affected by volume averaging of the nuggets. We used LA-ICP-MS to analyze thin sections from a 20-sample transect through a 60-m-thick section of siliciclastic strata in the Johnnie Formation in southeastern California and southern Nevada and a sample containing the basal breccia and host shale of the Acraman ejecta layer. The Johnnie Formation yielded six whole-rock Ir concentrations in the 1–10-ppb range, supported mainly by spot detections in Fe-rich nuggets that yielded concentrations well above analytical error. Four of the samples were collected within 40 cm of the top of a regional oolite marker horizon (Johnnie oolite) that averaged 3.7±0.6 ppb and included the highest estimated whole-rock value in the section of 8.2±0.4 ppb from a thin claystone immediately above the oolite; the other two samples were within 3 m of the oolite. The Acraman sample yielded 6.0±1.0 ppb for the ejecta horizon and 1.3±1.0 ppb for immediately subjacent host shale. Comparison of the Johnnie Formation Ir-depth profile to a published profile through the Acraman ejecta horizon and host shales suggests that the top of the oolite is correlative with the Acraman ejecta horizon. If a meteoritic source can be confirmed by further analysis of the claystone capping the oolite, it would provide a bed-scale temporal correlation between mid-Ediacaran strata of SW Laurentia and South Australia and provide a road map for similar reconnaissance studies in other sections.