Unraveling the igneous and overprinting alteration histories of volcanic terrains on Earth and Mars

不同的火成岩、水蚀变和沉积过程影响地球和火星上的火山和火山碎屑岩。作为加拿大航天局（CSA）支持的火星科学实验室（MSL）任务的参与科学家，我对区分这些过程对陆地地质问题的研究的相对贡献感兴趣，这些问题也与了解火星的演化有关，包括火星地幔的特征和微生物生命的潜力。火星科学实验室的好奇号探测车遇到了各种各样的岩性，包括演化的碱性火成岩、富含粘土的玄武岩泥岩、砂岩和砾岩。互补的陆地研究严重影响我们对这些岩石形成的环境和条件的解释。拟开展的研究包括：(1)刻画地幔交代作用、高压分选作用和地壳污染作用对地球和火星演化的碱性岩浆作用的相对影响；(2)限定大陆玄武岩火山场生物和非生物蚀变的条件和相对时间；(3)定量分析了沉积物输运和化学风化对火山碎屑物质的影响。我的总体方法是确定相关和有趣的岩石学问题，然后应用适当的分析技术。除了标准的现场和岩石学技术，分析包括但不限于：x射线荧光（XRF），电感耦合质谱（ICP-MS），用于整个岩石地球化学的α粒子x射线光谱（APXS），用于元素和同位素微观分析的电子探针和激光烧蚀ICP-MS，用于散装矿物鉴定的粉末x射线衍射（XRD），以及用于原位矿物相鉴定的微XRD和拉曼光谱。我预计在未来5年内支持6名硕士和至少3名理学士学生。学生将接受各种领域和分析技术的培训，并将在火星相关和火星任务数据集方面获得经验。

Diverse igneous, aqueous alteration, and sedimentary processes influence volcanic and volcaniclastic rocks on Earth and Mars. As a Canadian Space Agency (CSA)-supported Participating Scientist on the Mars Science Laboratory (MSL) mission, I am interested in differentiating the relative contributions of these processes for the investigation of terrestrial geologic problems that are also relevant to understanding the evolution of Mars, including the character of the Martian mantle and potential for microbial life. The MSL Curiosity rover has encountered a diverse suite of lithologies, including evolved alkaline igneous rocks, clay-rich basaltic mudstones, sandstones, and conglomerates. Complementary terrestrial studies critically influence our interpretations of the environment and conditions under which these rocks formed. Proposed research includes: (1) characterizing the relative influences of mantle metasomatism, high-pressure fractionation, and crustal contamination on evolved alkaline magmatism on Earth and Mars; (2) constraining the conditions and relative timing of biotic and abiotic alteration at continental basaltic volcanic fields; and (3) quantifying the effects of sediment transport and chemical weathering on volcanic fragmental materials. My overall approach is to identify relevant and interesting petrologic problems and then to apply the appropriate analytical techniques. In addition to standard field and petrographic techniques, analyses include but are not restricted to: X-Ray Fluorescence (XRF), Inductively coupled mass spectroscopy (ICP-MS), Alpha Particle X-ray Spectroscopy (APXS) for whole rock geochemistry, Electron microprobe and Laser Ablation ICP-MS for elemental and isotopic micro-analysis, Powder X-Ray Diffraction (XRD) for bulk mineral identification, and micro-XRD and Raman spectroscopy for in situ mineral phase identification. I anticipate supporting 6 MSc and at least 3 BSc students with this request over the next 5 years. Students will receive training in variety of field and analytical techniques and will become experienced in Mars relevant and Mars mission datasets.