57英尺长，9吨重，棘龙在大约1亿年前的白垩纪早期就开始四处活动。
Fifty-seven feet long and up to nine tons, spinosaurus started poking his head around the early Cretaceous some 100 million years ago.
侏罗纪晚期和白垩纪早期任一种食肉恐龙，形似霸王龙但体型较小。
Any of various carnivorous dinosaurs of the late Jurassic and early Cretaceous Periods, similar to but smaller than the tyrannosaur.
据悉，他们最早生活在白垩纪早期，亦即1亿4千5百万年前到6千5百万年前。
They date from the early Cretaceous period, which began around 145 million years ago and ended 65 million years ago.
下切谷由白垩纪早期准噶尔盆地南缘强烈的构造幕式挤压冲断作用导致的湖平面快速下降形成。
The back bulge slope belt in large compressional basins is the major area where large incised valleys are formed.
在犹他州和阿拉斯加州还发现了另一种鸟的“足迹”化石，但都无法追溯到白垩纪早期——恐龙时代的鼎盛时期。
Other bird "trace" fossils have been found in Utah and Alaska, but none from so far back as the early Cretaceous -- at the height of the age of dinosaurs.
王晓林还从该地区的沉积物推测道：“在大约1.2亿年前的白垩纪早期，一场强大的风暴夺走了这些翼龙的生命。”
Wang says that sediments in the areasuggest that the pterosaurs died in a large storm about 120 million years agoin the Early Cretaceous period.
这项发现将开花植物开始多样化的时间推到了大约一亿两千七百万年前，那时正是白垩纪的早期。
Its discovery pushes back the date of when flowering plants diversified to around 127 million years ago, during the early Cretaceous period.
这项发现将开花植物开始多样化的时间推到了大约一亿两千七百万年前，那时正是白垩纪的早期。
Its discovery pushes back the date of when flowering plants diversified to around 127 million years ago, during the early Cretaceous period.
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