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نقش سیل‌های عظیم در شکل گرفتن سطح مریخ

نقش سیل‌های عظیم در شکل گرفتن سطح مریخ

نتایج مطالعه اخیر محققان آمریکایی نشان می‌دهد سطح مریخ توسط سیل‌های عظیم باستانی شکل گرفته است.   به نقل از تی ای، به گفته محققان دانشگاه تکزاس در آستین (UT) آمریکا سیل عظیم دریاچه‌های دهانه‌های سیاره سرخ باعث ایجاد شکاف‌های عمیقی شده و سبب جابه‌جایی رسوبات بسیاری بر روی مریخ شده است. نتایج  مطالعه محققان نشان

نقش سیل‌های عظیم در شکل گرفتن سطح مریخ

نتایج مطالعه اخیر محققان آمریکایی نشان می‌دهد سطح مریخ توسط سیل‌های عظیم باستانی شکل گرفته است.

  به نقل از تی ای، به گفته محققان دانشگاه تکزاس در آستین (UT) آمریکا سیل عظیم دریاچه‌های دهانه‌های سیاره سرخ باعث ایجاد شکاف‌های عمیقی شده و سبب جابه‌جایی رسوبات بسیاری بر روی مریخ شده است. نتایج  مطالعه محققان نشان داد این سیل‌ها نقش مهمی در شکل دادن سطح مریخ ایفا کرده‌اند.
در حالی که فرسایش رودخانه‌ها روی زمین معمولاً یک روند طولانی و کند است اما در سیاره سرخ سیل عظیم حاصل از دریاچه‌های دهانه‌ای نقش بزرگی در شکل گیری سطح مریخ داشته است چرا که بر اساس تحقیقات انجام شده ، آنها شکاف‌های عمیقی را ایجاد کرده و سبب حرکت رسوبات بسیاری شده‌اند.
به گفته محققان این سیل‌ها چندین هفته به طول انجامیده‌اند. میلیاردها سال پیش وقتی سیاره سرخ آب مایع روی سطح خود داشت دریاچه‌های دهانه‌ای بسیاری در این سیاره وجود داشت.
برخی از دهانه‌ها می توانستند آب یک دریای کوچک را نگه دارند. اما هنگامی که مقدار آب نگهداری شده بیش از حد شود،  این آب لبه دهانه را شکافته و باعث جاری شدن سیل فاجعه باری می‌شود.
کاوشگرهای حاضر در مریخ دریاچه‌های دهانه‌ای و دره‌های رودخانه‌ای مریخ را به صورت جداگانه مورد بررسی قرار می‌دهند. طی این مطالعه محققان برای اولین بار بررسی کردند که چگونه ۲۶۲ دریاچه داری شکاف در سراسر سیاره سرخ، سطح مریخ را شکل داده است.
طی این مطالعه محققان فهرست موجود دره‌های رودخانه‌ای سیاره سرخ را مورد بررسی قرار دادند. آنها دره‌ها را به دو دسته تقسیم کردند: دره‌هایی که از لبه دهانه شروع می‌شوند و دره‌هایی که در جاهای دیگر شکل گرفته‌اند. محققان پس از مقایسه عمق ، طول و حجم انواع دره‌ها، دریافتند سیل ناشی از دره‌های رودخانه‌ای سبب فرسایش تقریبا یک چهارم حجم دره‌های رودخانه‌ای مریخ شده است.
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