Basalt Rocks
Basalt is an extrusive igneous rock that is very dark in color. It is the most common type of rock in the Earth's crust and it makes up most of the ocean floor.
It is made of many dark colored minerals such as pyroxene and olivine. Basalt also contains some light colored minerals such as feldspar and quartz, but the amounts are small. Typically, you can't see most of the mineral crystals without using a microscope because quick cooling prevents large crystals from forming.
Basalt forms when lava reaches the Earth's surface at a volcano or mid ocean ridge. The lava is between 1100 to 1250° C when it gets to the surface. It cools quickly, within a few days or a couple weeks, forming solid rock. Very thick lava flows may take many years to become completely solid.
Two Hawaiian words are used to describe the two types of volcanic basalt: 'a'a and pahoehoe. 'A'a basalts have rough surfaces (that make barefoot people cry, "Ah! Ah!" as they walk across it). They form from fast flowing lava. Pahoehoe basalts have a smooth glassy surface that looks like many ropes. The "ropes" form when the surface cools, becoming solid rock while lava flows beneath it.

玄武岩
玄武岩是一种颜色非常暗淡的喷出火成岩。它是地球表面上最常见的岩石种类并且组成了大部分的海底地面。
玄武岩由辉石和橄榄石这样暗色的矿物组成。玄武岩还含有某些亮色的矿物，像是长石和石英，但这些成分很少。通常，在不用显微镜的情况下你看不见大部分的矿物结晶，因为快速冷却时不会形成大块的结晶。
玄武岩由在火山或大洋中脊处到达地球表面的熔岩形成。到达地球表面时，熔岩的温度在1100至1250摄氏度之间。这些熔岩快速冷却，在几天至几个星期的时间里形成了固态的岩石。但浓稠的岩浆流会用上许多年才会完全凝固。
两个夏威夷语的词被用来描述两种不同的火山玄武岩：“a'a和pahoehoe”，a'a玄武岩有着粗糙的表面（所以光脚的人走在上面的时候会啊啊叫）。它们由快速排除的熔岩形成。pahoehoe玄武岩（绳状熔岩）有着看上去像是许多绳索的光滑1玻璃状表面。这些“绳索”的形成是因为熔岩表面冷却变为固态岩石而内部仍然在流动。