石灰岩

They would leave subtle clues in the isotopic composition of the limestone by shifting the ratios of light to heavy carbon and oxygen atoms in its calcium carbonate.

因为如果是那样的话，阳光将会被转换成大量的碳、氧原子保存到石灰岩中的碳酸钙里，而事实却是，岩层的同位素组成中没有留下任何蛛丝马迹。

However, this is an ordinary piece of chalk, the process of making some quite complicated, and made a first Cretaceous limestone, chalk and then add water, stirring, stirring evenly, and then poured into the model so that it solidified, it can be made of a pieces of chalk.

但是，就是一支如此普通的粉笔，制作的过程倒也有些繁琐，得先将石灰岩制成白垩，再将白垩加水搅拌，搅拌均匀后，再倒入模型中使其凝固，这样才能够制成一支粉笔。

As a matter of fact, more than seventy-five percent of the rocks exposed on the earth's surface consist of sedimentary rocks, such as sandstone, clay, shale and limestone, so it is not surprising we often see sedimentary rock on the earth's surface.

实际上，地球表面的百分之75出露都是沉积岩、粘土岩、页岩以及石灰岩。因此在地球表面经常见到积岩也就不足为奇了。

Has been proven there are 38 kinds of minerals, of which two kinds of fuel minerals, 12 kinds of metal minerals, 24 kinds of non-metallic minerals, coal, iron, gypsum, limestone, dolomite, bentonite, granite, marble, oil shale , refractory clay, such as in the province and the important position of national account, the comprehensive advantages of mineral resources is 0.73 degrees, in 11 cities in the second.

目前已探明的矿种有38种，其中燃料矿产2种、金属矿产12种、非金属矿产24种，煤、铁、石膏、石灰岩、白云岩、膨润土、花岗岩、大理石、油页岩、耐火粘土等在省内及全国均占重要地位，矿产资源综合优势度为0.73，在全省11个市中居第二位。

These are the principal aquifers of the UK. Chalk and particular sandstones, make up the 2 most important aquifers.

有很多的英国主要含水层，其中，石灰岩和特定的砂岩组成了2个最重要的含水层。

A caver overlooks razor-edged limestone pinnacles sharp enough to kill a man in Borneo's Tardis Cave.

一位探察洞穴的人俯看剃刀边石灰岩小尖塔锋利的足以杀死一名男子在婆罗洲的Tardis洞穴。

Photo Gallery: Cave Exploration A caver overlooks razor-edged limestone pinnacles sharp enough to kill a man in Borneo's Tardis Cave.

一位探察洞穴的人俯看剃刀边石灰岩小尖塔锋利的足以杀死一名男子在婆罗洲的Tardis洞穴。

Limestone can not be erosion by cavitating water jets on the condition of the most pump pressure, but sandstone were greatly erosion.

空化水射流在本实验设备能达到的最高泵压条件下无法冲蚀破碎石灰岩，而对砂岩却表现出巨大的冲蚀能力。

Photograph by John Stanmeyer, National GeographicThe Maya believed natural wells, such as the Xkeken cenote in Mexico's Yucatán, led to the underworld.

玛雅人相信，诸如墨西哥尤卡坦半岛上的斯科肯石灰岩坑之类的天然深井是通向地狱的。

Xkeken Cenote, Mexico

斯科肯石灰岩坑，墨西哥

I didn't watch TV last night, because it .

昨晚我没有看电视，因为电视机坏了。

Since this year, in a lot of villages of Beijing, TV of elevator liquid crystal was removed.

今年以来，在北京的很多小区里，电梯液晶电视被撤了下来。