沉积相（sedimentary facies）

What is the seating arrangement for future cars？

A．Passengers in the car may be seated facing one another.

B．The front seats will face forward and the back seats backward.

C．Special seats will be designed for children.

D．More seats win be added.

eneer of soil.

A．concealed

B．eroded

C．protected

D．softened

Hornfelsis a metamorphic rock formed when magma(molten rock) heats sedimentary rocks on Earth’s sur-face. According to Figure 1, hornfels is most likely amember of which of the following facies？

A.Facies A

B.Facies C

C.Facies E

D.Facies G

us rocks are commonly referred to as primary rocks because they are the original source of material found in sedimentaries and metamorphics. Igneous rocks compose the greater part of the earth's crust, but they are generally covered at the surface by a relatively thin layer of sedimentary or metamorphic rocks. Igneous rocks are distinguished by the following characteristics: (1) they contain no fossils; (2) they have no regular arrangement of layers; and (3) they are nearly always made up of crystals.

Sedimentary rocks are composed largely of minute fragments derived from the disintegration of existing rocks and in some instances from the remains of animals. As sediments are transported, individual fragments are assorted according to size. Distinct layers of such sediments as gravels, sand, and clay build up, as they are deposited by water and occasionally wind. These sediments vary in size with the material and the power of the eroding agent. Sedimentary materials are laid clown in layers called strata.

When sediments harden into sedimentary rocks, the names applied to them change to indicate the change in physical state. Thus, small stones and gravel cemented together are known as conglomerates; cemented sand becomes sandstone; and hardened clay becomes shale. In addition to these, other sedimentary rocks such as limestone frequently result from the deposition of dissolved material. The ingredient parts are normally precipitated by organic substances, such as shells of clams or hard skeletons of other marine life.

Both igneous and sedimentary rocks may be changed by pressure, heat, solution, or cementing action. When individual grains from existing rocks tend to deform. and interlock, they are called metamorphic rocks. For example, granite, an igneous rock, may be metamorphosed into a gneiss or a schist. Limestone, a sedimentary rock, when subjected to heat and pressure may become marble, a metamorphic rock. Shale under pressure becomes slate.

Which one of the following is a metamorphic rock？

A．Granite.

B．Shale.

C．Slate.

D．Limestone.

A.游牧民；游走的

B.沉积的、沉淀性的

C.基础的、简单的

D.补充的

A.tectonic

B.shallow

C.seismic

D.amplitude

A．increases in the carbon dioxide content of sedimentary rocks

B．the formation of bodies of water

C．decreases in the level of nitrogen

D．the formation of clouds

In Paragraph 1, the author introduces the debate between Neptunism and Plutonism by

A．providing information about the backgrounds of both of the geologists involved.

B．describing how scientists studied the planet before the creation of geology.

C．explaining the differences in the formation of sedimentary, igneous, and metamorphic rocks.

D．contrasting modern geologic knowledge with that of previous centuries.