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  • General

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  • 沉积岩分类

    Can you tell which type of rock these are?
    ::你能分辨出这些是哪种岩石吗?

    If you look up close, you would be able to see grains of sand. From this distance, you can see different layers from where the sand was laid down. This   is sandstone. The sand grains are  cemented  together to make sandstone. Sandstone is a common type of  sedimentary rock .
    ::如果你近距离看望,你就能看见沙粒。从这条距离看,你可以看到沙落地的不同层层。这是沙石。沙粒被凝固在一起制成沙石。沙石是一种常见的沉积岩。

    Types of Sedimentary Rocks
    ::沉积物岩类型

    The main types of   are  clastic  or chemical. Some sedimentary rocks are a third type,  organic .  Clastic sedimentary rocks  are made of  sediments . The sediments differ in size.  Chemical sedimentary rocks  are made of   that  precipitate  from saline  water . Organic sedimentary rocks are made from the bodies of organisms.
    ::一些沉积岩是第三类有机的,由沉积物制成,沉积物大小各异,化学沉积岩是由盐水沉淀的化学沉积岩制成,有机沉积岩由有机生物体制成。

    Clastic Sedimentary Rocks
    ::壳状沉积物岩

    Clastic sedimentary rocks  are grouped by the size of the sediment they contain. Conglomerate and breccia are made of individual stones that have been cemented together. In conglomerate, the stones are rounded. In breccia, the stones are angular. Sandstone is made of sand-sized particles. Siltstone is made of smaller particles. Silt is smaller than sand but larger than clay. Shale has the smallest grain size. Shale is made mostly of clay-sized particles and hardened mud.
    ::封状沉积岩按沉积物的大小分组,由凝固的单个石块组成团团和薄角,在联合体中,石块四舍五入,在粘合体中,石块是圆形的,在粘合体中,石块是角形的,沙石是由沙大小的颗粒制成,石石石石是由小颗粒制成,石石石石石由小颗粒制成,石石石石比沙子小,但比泥土大。Shale的颗粒大小最小。Shale大部分是粘土大小的颗粒和硬化的泥土制成。

    Rock Sediment Size Other Features
    Conglomerate Large Rounded
    Breccia Large Angular
    Sandstone Sand-sized  
    Siltstone Silt-sized, smaller than sand  
    Shale Clay-sized, smallest  

    When sediments settle out of calmer water, they form horizontal layers. One layer is  deposited  first, and another layer is deposited on top of it. So each layer is younger than the layer beneath it. When the sediments harden, the layers are preserved.
    ::当沉积物从较平静的水中沉积下来时,它们会形成水平层。一个层首先沉积,另一个层沉积在它的上面。所以每个层都比它下面的层小。当沉积物硬化时,这些层就会被保存。

    Chemical Sedimentary Rocks
    ::化学沉积岩

    Sedimentary rocks formed by the  crystallization  of chemical precipitates are called  chemical sedimentary rocks . Dissolved  ions  in fluids precipitate out of the fluid and settle out, just like the halite pictured below ( Figure   ).
    ::化学沉淀物结晶形成的沉淀石称为化学沉淀石,液体中的溶解离子从液体中沉淀出来并安顿下来,就像下面所描绘的沥青(图 ) 。

    A halite-encrusted cobble from the Dead Sea, showcasing mineral crystallization.

     

    The evaporite, halite, on a cobble from the Dead Sea, Israel.
    ::蒸发者 圣人 来自死海 以色列

    Living creatures can help chemicals become sedimentary rocks. Limestone is an example.
    ::活生生的生物可以帮助化学物质变成沉积岩。利姆斯通就是一个例子。

    Organic Sedimentary Rocks
    ::有机沉积岩

    The bodies of organisms can make a sedimentary rock. Plant bodies are lithified to become  coal . When shells are cemented together they make a type of limestone. So limestone can be considered chemical or organic.
    ::有机体可以制造沉积岩,植物体被石化成煤,罐壳被凝固后,会形成一种石灰岩,因此石灰石可以被视为化学或有机物。

    Some Common Sedimentary Rocks
    ::一些共同沉积岩

    Listed below are some common types of sedimentary rocks ( Table   ).
    ::下面列出一些常见的沉积岩(表)。

    Picture Rock Name Type of Sedimentary Rock

    Close-up of conglomerate clastic rock showing various non-organic sedimentary fragments.

     

    		 Conglomerate Clastic (fragments of non-organic sediments)

    Sample of breccia clastic sedimentary rock showing angular fragments and matrix.

     

    		 Breccia Clastic

    Close-up of sandstone surface showcasing distinct layers and textures of sedimentary rock.

     

    		 Sandstone Clastic

    A sample of siltstone, a type of clastic sedimentary rock, on a blue background.

     

    		 Siltstone Clastic

    Brown shale rock with layered texture, illustrating a type of sedimentary rock.

     

    		 Shale Clastic

    Various pieces of rock salt, showcasing different colors and textures.

     

    		 Rock salt Chemical precipitate

    Rock gypsum is a chemical precipitate, a type of sedimentary rock.

     

    		 Rock gypsum Chemical precipitate

    A piece of dolostone, a type of chemical sedimentary rock, characterized by its light color.

     

    		 Dolostone Chemical precipitate

    Surface of limestone showing bioclastic sediments, including fossilized shells and organic materials.

     

    		 Limestone Bioclastic  (sediments from organic materials, or plant or animal remains)

    A hand holding a piece of coal, representing organic sedimentary rock.

     

    		 Coal Organic

    Summary
    ::摘要

    • Sediments settle out of water in horizontal layers.
      ::沉积物从水中沉淀在水平层中。
    • Clastic sedimentary rocks are classified based on how they form and on the size of the sediments.
      ::根据岩的形成方式和沉积物的大小对板状沉积岩进行分类。
    • Chemical sedimentary rocks precipitate from fluids.
      ::化学沉积岩从液体中沉淀。

    Review
    ::回顾

    1. Describe the three main types of sedimentary rocks.
      ::描述三种主要的沉积岩。
    1. How can different types of limestone be bioclastic, chemical and organic?
      ::不同种类的石灰石如何能成为生物弹性、化学和有机物?
    1. List sedimentary rock types by grain size, from small to large.
      ::按谷物大小,从小到大,列出沉积岩类型清单。

    Explore More
    ::探索更多

    Use the resource below to answer the questions that follow.
    ::利用以下资源回答以下问题。

    1. List the three types of sedimentary rocks.
      ::列出三种沉积岩。
    1. Where and how are clastic rocks found?
      ::如何找到禁闭岩呢?
    1. How do clastic rocks form?
      ::幽闭岩石如何形成?
    1. Contrast conglomerates and breccia rocks.
      ::对比联合企业集团和布雷奇亚岩石。
    1. What can be found in clastic rocks?
      ::在幽闭岩石中可以找到什么?
    1. Explain the difference between layers and bands.
      ::解释分层和波段的区别。
    1. What can we learn from sedimentary rocks?
      ::我们从沉积岩中可以学到什么?
    1. How do chemical rocks form?
      ::化学岩石如何形成?
    1. What are bioclastic rocks?
      ::什么是生物冰块?
    1. List the two types of biocalstic rocks.
      ::列出两类生物岩层岩石。