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Why Is the Ocean Salty?
Description
The salinity of the oceans stems primarily from the erosion of rocks on land by slightly acidic rain, which dissolves minerals and carries them through rivers into the sea. As water evaporates from the ocean surface, these salts are left behind, their concentration steadily increasing over billions of years. Additional sources of salt include hydrothermal vents on the seafloor and underwater volcanic activity.
Original title
מדוע האוקיינוס מלוח?
מליחות האוקיינוסים נובעת בעיקר מתהליכי שחיקה של סלעים ביבשה על ידי גשם חומצי מעט, הממיס מינרלים ומוליך אותם דרך נהרות אל הים. עם התאיידות המים מהאוקיינוס, המלחים נותרים מאחור וריכוזם עולה לאורך מיליארדי שנים. מקורות נוספים למלחים הם פתחים הידרותרמיים בקרקעית הים ופעילות געשית תת-ימית.
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