Oxisol profile
Oxisol profile Oxisols are typically found in tropical climates. They are characterized by being deep, red, very strongly weathered soils. Very strongly weathered means that most of the original minerals, those inherited from the parent material, have been changed to new, secondary minerals. Oxisols, by definition have less than 10% of the original weatherable minerals remaining. Often, Oxisols will become irreversible hardened if cleared of natural vegetation and allowed to dry. In this Oxisol, found near Ione, California, the hardened laterite is a crust at the soil surface. What is a soil from tropical climates doing in Northern California? The soil represents a period of time, some 60 million years ago, when the climate of California was tropical. It was buried and later exhumed by natural processes. It is a very old soil that has reappeared at the earth's surface. It helps us to understand something about past climates and about processes that occur in tropical areas.

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