Answer:
Where hot rock nucleates at the core-mantle boundary and rises through the Earth's mantle becoming a diapir in the Earth's crust.
Step-by-step explanation:
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Diapir- a domed rock formation in which a core of rock has moved upward to pierce the overlying strata.
Core-mantle boundary- The core–mantle boundary of the Earth lies between the planet's silicate mantle and its liquid iron-nickel outer core.
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