请输入您要查询的英文单词:

 

单词 Petoskey stone
释义

Petoskey stone

英语百科

Petoskey stone

Unpolished Petoskey stone with cm scale.
A polished Petoskey stone

A Petoskey stone is a rock and a fossil, often pebble-shaped, that is composed of a fossilized rugose coral, Hexagonaria percarinata. The stones were formed as a result of glaciation, in which sheets of ice plucked stones from the bedrock, grinding off their rough edges and depositing them in the northwestern (and some in the northeastern) portion of Michigan's lower peninsula. In those same areas of Michigan, complete fossilized coral colony heads can be found in the source rocks for the Petoskey stones.

随便看

 

英汉双解词典包含3607232条英汉词条,基本涵盖了全部常用单词的翻译及用法,是英语学习的有利工具。

 

Copyright © 2004-2022 Newdu.com All Rights Reserved
京ICP备09058993号 更新时间:2025/8/7 22:54:33