Fate of Drilling Fluids during the South McMurdo Sound Project (SMS) of the Antarctic Geological Drilling Program (ANDRILL)

智力优势：PI建议利用水文地质学家使用的计算机模型来确定污染物的去向和传输，并确定ANDRILL SMS岩心中钻井液污染的程度。对于这些模型，以前收集的岩性、孔隙度、裂缝密度、裂缝类型、裂缝方向、钻井液漏失、钻井液特性和温度等测井资料将被用作输入参数。此外，还将确定钻井液的生物降解和吸附常数，并将其纳入模型。钻探过程中使用的钻井液样本以及返回的钻井液都是使用标准微生物采样技术在钻探现场采集的。流体将在好氧和厌氧条件下在现场温度下进行测试，以确定生物降解常数。钻井液和岩心样品之间的吸附将使用标准等温线方法确定。钻井液的地球化学和微生物指纹以及生物降解过程中的变化将决定钻井液对南极麦克默多海峡南部各种地下岩性单元内孤立微生物群落和地球化学的潜在影响。如果这项研究被认为是必要的，这项研究的结果可能会为未来的探索开发危害较小的方法提供指导方针。广泛的影响：这个拟议的项目将培养一名研究生。该项目中开发的样品分析方法将为今后类似兴趣的研究提供指导，并将提高对南极洲地质钻探的生态影响的了解。这项研究的结果将作为未来研究的参考，这些研究考察了新开发和改进的样品采集方法，用于未来原始环境下的勘探钻井项目。圆周率对于南极研究来说是新的。

Intellectual Merit: The PI proposes to utilize computer models used by hydrogeologists to establish the fate and transport of contamination and determine the extent of drilling fluid contamination in the ANDRILL SMS core. For these models, previously collected logs of lithology, porosity, fracture density, fracture type, fracture orientation, drilling fluid loss, drilling fluid characteristics and temperature will be used as input parameters. In addition, biodegradation and sorption constants for the drilling fluid will be determined and incorporated into the models. Samples of drilling fluids used during coring as well as the return fluids were collected at the drill site using standard microbiological sampling techniques. Fluids will be tested at in situ temperatures under aerobic and anaerobic conditions to determine biodegradation constants. Sorption will be determined between the drilling fluids and core samples using standard isotherm methods. Geochemical and microbial fingerprints of the fluids and the changes during biodegradation will determine the potential impact of the drilling fluids on the isolated microbial communities and the geochemistry within various subsurface lithologic units beneath the southern McMurdo Sound in Antarctica. The results of this study could potentially provide guidelines on developing less detrimental methods for future exploration, if deemed necessary through this research.Broader impacts: This proposed project will train a graduate student. The methods developed for analyses of samples in this project will serve as a guide for future studies of similar interest and will improve the understanding of ecological impacts of geologic drilling in Antarctica. The results of this study will be used as a reference for comparison with future studies examining newly developed, and improved, sample collection methods in future exploratory drilling projects in pristine environments. The PI is new to Antarctic research.