A rock unit that cross cuts another rock unit is younger than the rock through which it cuts
Yes. During emplacement via magma, they fill voids and displace the rock that already is in place.
Extrusive rocks which cool more rapidly than intrusive rocks generally have smaller crystals.
The melted rock of the igneous intrusion pushed its way into cracks and made previously existing rock weaker. The intrusions only became rock when they cooled and solidified, therefore they are younger than the rocks in which they are embedded.
Because the rocks have to be there first, all faults are younger than the rocks they end up cutting across. In regard to sedimentary rock layers, each layer is younger than the one below it.
The longer that magma is able to cool, the larger the crystals will be. Intrusive rocks will have larger crystals than extrusive rocks. For example granite (intrusive) has larger grains than rhyolite (extrusive).
principle of original horizontality
Extrusive rocks which cool more rapidly than intrusive rocks generally have smaller crystals.
The melted rock of the igneous intrusion pushed its way into cracks and made previously existing rock weaker. The intrusions only became rock when they cooled and solidified, therefore they are younger than the rocks in which they are embedded.
No. Intrusive rocks have larger crystals because the magma would have taken longer to cool and solidify than extrusive magma.
The rocks are underground so intrusive rocks are under pressure so its harder.
Because the rocks have to be there first, all faults are younger than the rocks they end up cutting across. In regard to sedimentary rock layers, each layer is younger than the one below it.
The longer that magma is able to cool, the larger the crystals will be. Intrusive rocks will have larger crystals than extrusive rocks. For example granite (intrusive) has larger grains than rhyolite (extrusive).
Generally, false. Intrusive rocks cool far more slowly than extrusive ones, so the crystals have time to grow larger.
Extrusive rocks are formed outside of earths surface. Intrusive rocks are formed inside earths surface.
Because intrusive rocks cool more slowly which makes the rocks larger.
Intrusive rocks are under pressure so they are usually harder.
They are formed from hardened lava which comes up from the ground and hardens inside the rock, which happens of course after the other rocks have already formed.
Rocks usually contain a mixture of minerals.