To ascertain the provenance of water reaching wetlands in an area sustaining a population of Pleistocene–Holocene foragers, 87-strontium/86-strontium isotopic ratios (87Sr/86Sr) of mollusks from channels of the Old River Bed inland delta of central Utah were measured. Potential provenances examined included overflow from Pleistocene–Holocene Lake Gunnison, ground water flow from the Sevier basin, ground water discharge from piedmont aquifers infiltrated by Lake Bonneville, and ground waters from local regional aquifers. Old River Bed inland delta channels active from ~13.2 cal ka BP until ~11.2 cal ka BP have 87Sr/86Sr values of 0.70930–0.71049 that are consistent with water sourced from Lake Gunnison in the Sevier basin. Inland delta channels active from ~11.2 cal ka BP until shortly after ~9.3 cal ka BP have 87Sr/86Sr values of 0.70977–0.71033, suggesting ground water flowed from the Sevier basin during the early Holocene. Ratios of 87Sr/86Sr did not match known values for Lake Bonneville, but the youngest Old River Bed inland delta channel system has an 87Sr/86Sr ratio consistent with a local ground water source, perhaps Government Creek. Consistent ground water discharge may explain the persistence of foragers in the region despite the increasingly arid climate of the Great Basin.

中文翻译：

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更新世-全新世过渡时期旧河床内陆三角洲的水源和犹他州中部塞维尔盆地的地下水流

为了确定在维持更新世-全新世觅食者种群的地区到达湿地的水的来源，87-锶/86-锶同位素比率（87锶/86测量了犹他州中部老河床内陆三角洲河道中软体动物的 Sr)。检查的潜在来源包括更新世-全新世甘尼森湖的溢流、塞维尔盆地的地下水流、邦纳维尔湖渗透的山前含水层的地下水排放以及当地区域含水层的地下水。旧河床内陆三角洲通道活跃，从 ~13.2 cal ka BP 到 ~11.2 cal ka BP87锶/86Sr 值为 0.70930–0.71049，与来自塞维尔盆地甘尼森湖的水相一致。内陆三角洲通道从~11.2 cal ka BP 到~9.3 cal ka BP 后不久活跃87锶/86Sr 值为 0.70977-0.71033，表明地下水在全新世早期从塞维尔盆地流出。比率87锶/86Sr 与博纳维尔湖的已知值不匹配，但最年轻的老河床内陆三角洲河道系统具有87锶/86Sr 比率与当地地下水源一致，可能是政府溪。尽管大盆地的气候越来越干旱，但持续的地下水排放可以解释该地区觅食者的持续存在。