2007-12-19 03:27:43 · 3 answers · asked by Horsejumper95 2 in Science & Mathematics ➔ Earth Sciences & Geology
They would be called secondary rocks because they form from sediments which are broken down from other rocks.
Igneous would be a Primary rock because it forms from Magma, not parts of other rocks. Though if you follow the rock cycle, other rocks help make magma. Since the pool of magma is so big, we would consider that as having negligible impact.
Metamorphic could also be looked at as Secondary because it from adding heat and pressure to either Sedimentary or Igneous rocks.
2007-12-19 05:09:14 · answer #1 · answered by TripCyclone 3 · 1⤊ 0⤋
They are the result of other rocks, like igneous or metamorphic rocks, breaking down. In other words, you cannot have a sedimentary rock with out some other rock breaking down first.
Though, I have rarely heard them referred to as this. Not all sedimentary rocks are secondary. Coal and limestone and other bioclastic and clastic sed rocks are not secondary.
2007-12-19 12:13:24 · answer #2 · answered by Lady Geologist 7 · 2⤊ 0⤋
Because they form from other rocks after the first rocks erode.
2007-12-19 11:35:17 · answer #3 · answered by CNJRTOM 5 · 1⤊ 0⤋