کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
5779732 1634682 2017 8 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
The geochemistry of Don Juan Pond: Evidence for a deep groundwater flow system in Wright Valley, Antarctica
ترجمه فارسی عنوان
ژئوشیمی دان جون پوند: شواهدی برای یک جریان جریان آب زیرزمینی عمیق در دره راایت، قطب جنوب
کلمات کلیدی
دون ژان پوند، دره های خشک قطب جنوب، کلرید کلسیم، آبهای زیرزمینی، مدل سازی ژئوشیمیایی، مریخ،
موضوعات مرتبط
مهندسی و علوم پایه علوم زمین و سیارات علوم زمین و سیاره ای (عمومی)
چکیده انگلیسی


- Deep groundwaters are the source of salts to Don Juan Pond.
- Brines in Don Juan Pond have only undergone closed-basin evaporation for up to a year.
- Don Juan Pond is an upwelling from a regional, flow-through groundwater system.
- Brines in Don Juan Pond are recycled into the subsurface over yearly timescales.

Don Juan Pond (DJP), Antarctica, is one of the most unusual surface waters on Earth because of its CaCl2-rich composition. To investigate the evolution of pond waters during closed-basin evaporation and to understand the source of brines responsible for the chemistry of DJP, we apply a newly developed low-temperature aqueous model in the Na-K-Ca-Mg-Cl system to DJP. By modeling the closed-basin evaporation of DJP and comparing ionic ratios between DJP surface water, deep groundwater, shallow groundwater, and other surface chemistries in Wright Valley, we find that DJP is best explained by upwelling deep groundwater, as opposed to recent hypotheses proposing shallow groundwater sources. The early closed-basin evolution of brines in our model accurately predicts observed chemistries in DJP; however, late-stage closed-basin evaporation produces Mg-K-rich brines and salts that do not match the CaCl2-rich brine in DJP. Based on groundwater inflow rates to DJP, we estimate that even the most concentrated brines in DJP have undergone closed-basin evaporation for less than a year. To explain the observed lack of Mg2+ and K+ accumulation in DJP over time, and the surprisingly young age for the brines, we deduce that DJP is a localized upwelling from a regional groundwater flow-through system in which evaporated DJP brines are recycled back into the subsurface over yearly timescales. The existence of a regional groundwater flow system beneath DJP has implications for water and solute budgets in cold desert ecosystems, and may provide clues for the formation of groundwater and aqueous flows on Mars.

ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Earth and Planetary Science Letters - Volume 474, 15 September 2017, Pages 190-197
نویسندگان
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