📖 原文
(1) The hard, rigid plates that form the outermost portion of the Earth are about 100 (2) kilometers thick. These plates include both the Earth's crust and the upper mantle. (3) The rocks of the crust are composed mostly of minerals with light elements, like (4) aluminum and sodium, while the mantle contains some heavier elements, like iron and (5) magnesium. Together, the crust and upper mantle that form the surface plates are called (6) the lithosphere. This rigid layer floats on the denser material of the lower mantle the way a wooden raft floats on a pond. The plates are supported by a weak, plastic layer of the lower mantle called the asthenosphere. Also like a raft on a pond, the lithospheric (9) plates are carried along by slow currents in this more fluid layer beneath them. (10) With an understanding of plate tectonics, geologists have put together a new history for the Earth's surface. About 200 million years ago, the plates at the Earth's surface (12) formed a "supercontinent" called Pangaea. When this supercontinent started to tear (13) apart because of plate movement, Pangaea first broke into two large continental masses with a newly formed sea that grew between the land areas as the depression filled with (15) water. The southern one - which included the modern continents of South America, (16) Africa, Australia, and Antarctica - is called Gondwanaland. The northern one - with (17) North America, Europe, and Asia - is called Laurasia. North America tore away from Europe about 180 million years ago, forming the northern Atlantic Ocean. (19) Some of the lithospheric plates carry ocean floor and others carry land masses or a combination of the two types. The movement of the lithospheric plates is responsible (21) for earthquakes, volcanoes, and the Earth's largest mountain ranges. Current (22) understanding of the interaction between different plates explains why these occur (23) where they do. For example, the edge of the Pacific Ocean has been called the "Ring of (24) Fire" because so many volcanic eruptions and earthquakes happen there. Before the (25) 1960's, geologists could not explain why active volcanoes and strong earthquakes were concentrated in that region. The theory of plate tectonics gave them an answer.
❓ 试题解析
问题 9： With which of the following topics is the passage mainly concerned?
A. The contributions of the theory of plate tectonics to geological knowledge
B. The mineral composition of the Earth's crust
C. The location of the Earth's major plates
D. The methods used by scientists to measure plate movement
✅ 正确答案： A）The contributions of the theory of plate tectonics to geological knowledge
📝 解析： 全文讨论板块构造理论对理解地球表面历史（超大陆、板块运动）以及地震、火山等现象的贡献。
💡 解题技巧： 主旨题看第二段首句及末段。
问题 10： According to the passage, the lithospheric plates are given support by the
A. upper mantle
B. ocean floor
C. crust
D. asthenosphere
✅ 正确答案： D）asthenosphere
📝 解析： “The plates are supported by a weak, plastic layer of the lower mantle called the asthenosphere”。
💡 解题技巧： 细节题定位“supported by”。
问题 11： The author compares the relationship between the lithosphere and the asthenosphere to which of the following?
A. Lava flowing from a volcano
B. A boat floating on the water
C. A fish swimming in a pond
D. The erosion of rocks by running water
✅ 正确答案： B）A boat floating on the water
📝 解析： “This rigid layer floats on the denser material ... the way a wooden raft floats on a pond”。
💡 解题技巧： 比喻题定位“the way a wooden raft floats on a pond”。
问题 12： The word “one” in line 15 refers to
A. movements
B. masses
C. sea
D. depression
✅ 正确答案： B）masses
📝 解析： “Pangaea first broke into two large continental masses ... The southern one ... The northern one” — one 指 mass。
💡 解题技巧： 代词题找前文并列结构中的名词（masses）。
问题 13： According to the passage, the northern Atlantic Ocean was formed when
A. Pangaea was created
B. plate movement ceased
C. Gondwanaland collided with Pangaea
D. parts of Laurasia separated from each other
✅ 正确答案： D）parts of Laurasia separated from each other
📝 解析： “North America tore away from Europe about 180 million years ago, forming the northern Atlantic Ocean” — 北美和欧洲分离。
💡 解题技巧： 细节题定位“North America tore away from Europe”。
问题 14： The word “carry” in line 19 could best be replaced by
A. damage
B. squeeze
C. connect
D. support
✅ 正确答案： D）support
📝 解析： “Some of the lithospheric plates carry ocean floor and others carry land masses” — carry = 承载/支撑。
💡 解题技巧： 词汇题：carry = support = bear。
问题 15： In line 25, the word “concentrated” is closest in meaning to which of the following?
A. Allowed
B. Clustered
C. Exploded
D. Strengthened
✅ 正确答案： B）Clustered
📝 解析： “active volcanoes and strong earthquakes were concentrated in that region” — concentrated = 集中/聚集。
💡 解题技巧： 词汇题：concentrated = clustered = gathered。
问题 16： Which of the following can be inferred about the theory of plate tectonics?
A. It is no longer of great interest to geologists.
B. It was first proposed in the 1960's.
C. It fails to explain why earthquakes occur.
D. It refutes the theory of the existence of a supercontinent.
✅ 正确答案： B）It was first proposed in the 1960's.
📝 解析： “Before the 1960's, geologists could not explain ... The theory of plate tectonics gave them an answer” — 暗示该理论在1960年代出现或被广泛接受。
💡 解题技巧： 推理题定位“before the 1960's”的对比。
问题 17： The paragraph following the passage most probably discusses
A. why certain geological events happen where they do
B. how geological occurrences have changed over the years
C. the most unusual geological developments in the Earth's history
D. the latest innovations in geological measurement
✅ 正确答案： A）why certain geological events happen where they do
📝 解析： 末段提到板块运动解释地震和火山为何发生在特定地点，下文可能进一步解释具体机制。
💡 解题技巧： 续写题看末段留下的讨论空间。
🌐 中文翻译
构成地球最外部的坚硬 rigid plates 约有100公里厚。这些板块包括地壳和上地幔。地壳的岩石主要由含有轻元素（如铝和钠）的矿物组成，而地幔含有一些更重的元素，如铁和镁。地壳和上地幔一起构成表面板块，称为岩石圈。这一刚性层漂浮在密度更大的下地幔 material 上，就像木筏漂浮在池塘上一样。板块由下地幔中一个称为软流圈的弱而具可塑性的层支撑。也像池塘上的木筏一样，岩石圈板块被它们下面这一更具流动性的层中的缓慢 currents 携带移动。 通过对板块构造的理解，地质学家为地球表面整理出了一段新的历史。大约2亿年前，地球表面的板块形成了一个被称为“盘古大陆”的超大陆。当这个超大陆因板块运动开始撕裂时，盘古大陆首先分裂成两个巨大的大陆块，随着洼地充满水，陆地之间形成了一片新生的海洋。南部的那块——包括现代南美洲、非洲、澳大利亚和南极洲——被称为冈瓦纳古陆。北部的那块——包括北美洲、欧洲和亚洲——被称为劳亚古陆。北美洲大约在1.8亿年前从欧洲撕裂开来，形成了北大西洋。 一些岩石圈板块承载着洋底，另一些承载着陆地或两者的组合。岩石圈板块的运动是地震、火山和地球最大山脉的原因。目前对不同板块之间相互作用的理解解释了为什么这些现象发生在它们所在的地方。例如，太平洋边缘被称为“火环”，因为那里发生如此多的火山喷发和地震。在20世纪60年代之前，地质学家无法解释为什么活火山和强烈地震 concentrated 在该地区。板块构造理论给了他们答案。
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