1. The presence of microtektites in the sediment confirmed that a meteorite impact had occurred millions of years ago.
（沉积物中存在微小玻璃小球证实了数百万年前发生过一次陨石撞击事件。）
2. Scientists study microtektites to learn more about the history of asteroid impacts on Earth.
（科学家研究微小玻璃小球，以了解更多关于陨石在地球上的撞击历史。）