These sandstone bodies form elongate lenses.是什么意思？

These sandstone bodies form elongate lenses.

这些砂岩体形成伸长的透镜体.

these

adj. 这些的；pron. 这些；

例句
There's lots of money about these days for schemes like this.
近来这类计划资金充足。

sandstone

n. 砂岩，砂石；

例句
...a sandstone bed.
砂岩层

bodies

n. 身体( body的名词复数 )，尸体，团体，物体；

例句
Ballistic tests have matched the weapons with bullets taken from the bodies of victims.
弹道测试表明,武器和受害者体内取出的子弹相吻合。

form

n. 形状，形式，外形，方式，表

例句
A household radiator absorbs energy in the form of electric current and releases it in the form of heat.
家用取暖器吸收电流能量，再以热量的形式释放出来。

elongate

vt. 延长，加长；

例句
These elongate sand bodies are attached to a bulge of the mainland.
这些长条形砂体连接于主陆的突出部位.

lenses

n. 透镜，镜头( lens的名词复数 )，眼睛中的水晶体；

例句
Why aren't all lenses supplied with a lens hood?
为什么不给所有的镜头都配上遮光罩呢？