A fault.
A fault is a break in the Earth's crust where pieces of the crust move relative to each other. This movement can cause earthquakes as stress builds up along the fault line and is released suddenly. Faults are common in regions where tectonic plates interact and are essential for understanding earthquake hazards.
Earth's crust is typically between 5 to 70 kilometers (3 to 44 miles) thick, with an average thickness of around 40 kilometers (25 miles). However, this thickness can vary depending on location, with oceanic crust being thinner than continental crust.
Crust
Block mountains are formed when geological faults cause blocks of the Earth's crust to move vertically, leading to the formation of tall mountain ranges. An example of a block mountain is the Sierra Nevada in California, USA. Rift valleys, on the other hand, are formed by the stretching and thinning of the Earth's crust, leading to the development of deep valleys. The East African Rift Valley is a well-known example of a rift valley.
The crust is typically thicker beneath continents compared to oceans. Continental crust can be up to 40 km thick, while oceanic crust is generally around 5-10 km thick.
Oxygen is the most abundant element in the Earth's crust, making up about 46.6% of its mass.
why do pieces of earths earliest crust not exist today
A fault
the answer is focus
The crust.
Earths under crust surrounded by Upper Mantle (35-60 km) .The mantle is composed of sillicate rocks that are rich in iron and magnesium relative to the overlying crust.
a fault
Focus
A volcano is the opening called in the earths crust called through which lava gases and other pieces of rock erupt.
superposition a&c- Jackie
The Earth's outer layer is called the Crust, and the crust is split into various types of tectonic plates.
most times earthquakes occur
lsrge, brittle pieces of earths out shell composed of crust and uppermost mantle.