题目解析：
先看题干：Herodotus这个人对于三角洲的观察为什么是重要的呢？抓出关键词Herodotus，Delta和significant回原文第一段定位。第一段第四句也就是我们第一题里分析过的那句同时出现了这三个关键词——需要考生关注的是significant并没有原样出现，而是通过important同义替换了。考生在关键词定位时注意不要只看题干里出现的词，要注意原文中出现同义替换的地方，这往往就是答案所在。再次复习下这一句的意思，这次我们把修饰的从句剃掉，直接抓出主干：More important than the amount of time Herodotus computed, was the notion. 与Herodotus计算出的数值相比，有个概念更重要。再细看，这个notion是什么呢？one could estimate ages of geologic features by determining rates of the processes responsible for such features, and then assuming the rates to be roughly constant over time.本句大致意思是：一个人可以通过一些方法来估计地理特征的年龄。理解原文到这个程度后，我们返回题目，看看四个选项：A 提供了关于什么什么的具体的记录，本句里没有，排除；B 发现了一种计算地理特征的年龄，对了；C 推测出这个三角洲跟地球一样老，胡说八道；D 推测这个河流什么时候泛滥，原句没提。选B。
One of the first recorded observers to surmise a long age for Earth was the Greek historian Herodotus, who lived from approximately 480 B.C. to 425 B.C. He observed that the Nile River Delta was in fact a series of sediment deposits built up in successive floods. By noting that individual floods deposit only thin layers of sediment, he was able to conclude that the Nile Delta had taken many thousands of years to build up. More important than the amount of time Herodotus computed, which turns out to be trivial compared with the age of Earth, was the notion that one could estimate ages of geologic features by determining rates of the processes responsible for such features, and then assuming the rates to be roughly constant over time. Similar applications of this concept were to be used again and again in later centuries to estimate the ages of rock formations and, in particular, of layers of sediment that had compacted and cemented to form sedimentary rocks.
