Chemical and isotopic data on gases and waters for thermal and non-thermal features across Yellowstone National Park (2003-2015)

Degassing thermal features at Yellowstone National Park include spectacular geysers, roiling hot springs, bubbling mud pots, fumaroles, frying pans, and areas of passive degassing characterized by steaming ground. Most of these features are readily identified by visible clouds of steam that are occasionally accompanied by a strong rotten egg odor from emissions of hydrogen sulfide gas. Gas compositions typically are greater than 90% carbon dioxide with lesser amounts of helium, hydrogen, hydrogen sulfide, methane, nitrogen and other trace components. The composition of the gas and relative amounts of gas and steam relate both to the type of feature as well as the geographic location within the park. In 2003 we began a long-term field study of Yellowstone gases with a goal of obtaining complete chemical analyses from a variety of features from all areas of the park. Results from samples collected through 2012 are published in numerous journal articles and 2 data releases (see below). Synthesis of these studies enabled us to delineate areas dominated by crustal and magmatic gas sources and to tease out information on additional sources of gas related to sedimentary and metamorphic processes. This report compiles the early gas data and new gas and water data from samples collected in 2014 and 2015. In total there are 190 analyses of gas collected in evacuated bottles containing sodium hydroxide, 30 analyses of gas collected in dry evacuated bottles, and 62 water analyses from thermal and non-thermal features. Some of the analyses represent replicate samples collected in different bottles on the same day, others are samples collected from the same location in different years, and some sites were only sampled once. The analytical results include major and trace element chemistry for the gases and waters and isotope values for water and steam (d18O, dD), carbon dioxide (d13C), methane (d13C), helium (3He/4He), neon (20Ne/22Ne and 21Ne/22Ne), and argon (38Ar/36Ar and 40Ar/36Ar). All data in this report supersede previously published analyses. The gas and water data are presented in 3 tables and are keyed to a group number, from 1 through 20. Samples in groups 2 through 10 and 12 through 20 tend to be in close proximity. Group 11 includes samples from general locations across Eastern Yellowstone. Samples keyed to group 1 (miscellaneous) are not co-located. The reader is directed to early publications for details on sampling and analytical methods and for in depth discussions regarding interpretations of the gas data.

黄石国家公园内的脱气热液景观涵盖壮观的间歇泉、翻涌的热泉、冒泡的泥锅、喷气孔、煎锅状热池，以及以地面冒汽为特征的被动脱气区域。这类景观大多可通过可见的蒸汽云识别，部分景观还会伴随因硫化氢气体释放而产生的浓烈臭鸡蛋气味。气体组分通常以二氧化碳为主，占比超过90%，其余含量较少的组分包括氦、氢、硫化氢、甲烷、氮及其他痕量成分。气体组分以及气、汽相对含量既与地貌类型相关，也与公园内的地理位置有关。2003年，本团队启动了针对黄石公园气体的长期野外研究，目标是对公园全域各类热液景观的气体开展完整的化学分析。截至2012年采集的样本分析结果已发表于多篇期刊论文与2份数据公报（详见下文）。对这些研究成果的综合分析帮助本团队划定了以地壳源与岩浆源气体为主的区域，并梳理出与沉积作用、变质作用相关的其他气体来源信息。本报告整合了早期气体数据，以及2014年与2015年采集样本的新增气体与水体数据。本次整合的数据总计包含190组采用含氢氧化钠的真空瓶采集的气体分析结果、30组采用干燥真空瓶采集的气体分析结果，以及62组来自热液与非热液景观的水体分析结果。部分分析结果对应单日使用不同容器采集的平行样本，部分为不同年份在同一地点采集的样本，还有部分点位仅被采样一次。分析结果涵盖气体与水体的主量及痕量元素化学组成，以及水体、蒸汽（δ18O、δD）、二氧化碳（δ13C）、甲烷（δ13C）、氦（3He/4He）、氖（20Ne/22Ne与21Ne/22Ne）及氩（38Ar/36Ar与40Ar/36Ar）的同位素比值。本报告中的所有数据均替代此前已发表的分析结果。气体与水体数据以3张表格呈现，并通过1至20的组号进行索引。组2至组10以及组12至组20的样本通常采集自相邻区域；组11的样本涵盖黄石公园东部的多个通用采样点位；而组1（杂项）的样本未限定于同一采样点位。有关采样与分析方法的细节，以及气体数据解译的深入讨论，请参阅早期发表的文献。