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Earth & Geophysics稀土元素稀土元素（英语：rare-earth element，REE），或称稀土金属，简称稀土，是元素周期表中第3族之钪、钇和镧系元素共17种金属化学元素的合称，皆属于副族元素。稀土元素皆为质地较软的银白色金属，彼此之间具有非常相似的化学性质，总是在矿床中共生，故难以分离、提取。 与其名称暗示的不同，实际上稀土元素在地壳中的丰度并不低（放射性的钷除外），其中含量最高的铈在地壳元素丰度排名第25，占0.0068%，这与铜相当，并不少见。稀土元素在矿藏中常与放射性锕系元素共生，以钍为主，铀矿中较为少见。只有钷因为是稀土元素中唯一的放射性元素，且其所有同位素的半衰期都很短，在自然界中主要作为铀-238自发裂变的产物而痕量生成于铀矿中，含量才极为稀少。总之，虽然稀土元素并不稀有，但由于其地球化学特性，它们在地壳中的分布相当分散，很少有稀土元素富集到容许商业开采的程度；此外，其彼此之间相似的化学性质导致它们倾向于两两或多种一起伴生于矿物中，而难以将稀土元素彼此单独分离，导致开采和提取上的困难，因此被称为“稀土”元素。 稀土元素属于化学性质较活泼的金属，在周期表的各类金属元素中其反应性仅次于碱金属和碱土金属，其中镧系元素的反应性有随着原子序数增加而逐渐降低的趋势（铕除外）。室温下，稀土金属在空气中表面会逐渐失去光泽；与水蒸气接触会反应生成氧化物；与冷水接触则会反应生成氢氧化物并释出氢气。在400°C以上的高温中会自燃。稀土元素及其化合物在绝大多数生物体内并没有已知的生物学功能，且其水溶性化合物具有轻度至中度毒性，但难溶性化合物则没有。但稀土元素在电气及电子元件、激光器、玻璃、磁铁和工业及化学催化剂等领域中有着多样且广泛的应用，由于它们在产业中不像铁和铝等卑金属需要使用庞大的体积或消耗巨大的用量，且大多应用于较专业的用途，因此它们的名称和属性并不为一般大众所熟知。在日常生活中最容易见到的可能是磁性很强的钕磁铁（人造永磁体），在一些商家作为新奇的玩具出售。
The rare-earth elements (REE), also called rare-earth metals, or rare earths, are a set of 17 nearly indistinguishable lustrous silvery-white soft heavy metals. The 15 lanthanides (or lanthanoids), along with scandium, and yttrium, are usually included as rare earths. Compounds containing rare-earth elements have diverse applications in electrical and electronic components, lasers, glass, magnetic materials, and industrial processes. Rare-earths are to be distinguished from critical minerals, which are materials of strategic or economic importance that are defined differently by different countries, and rare-earth minerals, which are minerals that contain one or more rare-earth elements as major metal constituents. The term "rare-earth" is a misnomer, because they are not actually scarce, but because they are found only in compounds, not as pure metals, and are difficult to isolate and purify.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 居里点（英语：Curie point），又作居里温度（Curie temperature，Tc）或磁性转变点。是指磁性材料中自发磁化强度降到零时的温度，是铁磁性或亚铁磁性物质转变成顺磁性物质的临界点。低于居里点温度时该物质成为铁磁体，此时和材料有关的磁场很难改变。当温度高于居里点时，该物质成为顺磁体，磁体的磁场很容易随周围磁场的改变而改变。这时的磁敏感度约为10−6。居里点由物质的化学成分和晶体结构决定。居里温度是以皮埃尔·居里命名的，他表明在临界温度以上磁性材料会失去磁性。 居里点的温度可以用平均场理论估计。
In physics and materials science, the Curie temperature (TC), or Curie point, is the temperature above which certain materials lose their permanent magnetic properties, which can (in most cases) be replaced by induced magnetism. The Curie temperature is named after Pierre Curie, who showed that magnetism is lost at a critical temperature. The force of magnetism is determined by the magnetic moment, a dipole moment within an atom that originates from the angular momentum and spin of electrons. Materials have different structures of intrinsic magnetic moments that depend on temperature; the Curie temperature is the critical point at which a material's intrinsic magnetic moments change direction. Permanent magnetism is caused by the alignment of magnetic moments, and induced magnetism is created when disordered magnetic moments are forced to align in an applied magnetic field. For example, the ordered magnetic moments (ferromagnetic, Figure 1) change and become disordered (paramagnetic, Figure 2) at the Curie temperature.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 流域（英语：drainage basin）是以分水岭为界的一个河流、湖泊或海洋等的所有水系所覆盖的区域，以及由水系构成的集水区。地面上以分水岭为界之区域称为流域。流域内之径流集中于最低点而流出。最低点通常设有水文站量测流量或水位。流域内水文现象与流域特性有密切关系。 按水体是否与海洋连通，可分为外流区和内流区。外流区可按连通的大洋分为太平洋流域、大西洋流域、印度洋流域和北冰洋流域。并可进一步按河流、湖泊甚至一个支流细分，如长江流域。世界上流域面积最大的河流是亚马孙河。 太平洋流域约占地球上陆地面积的13%，印度洋流域也占约13%，而大西洋流域最多，约占47%──这其中包括密西西比河、刚果河和亚马孙河等大河流域。
A drainage basin is an area of land in which all flowing surface water converges to a single point, such as a river mouth, or flows into another body of water, such as a lake or ocean. A basin is separated from adjacent basins by a perimeter, the drainage divide, made up of a succession of elevated features, such as ridges and hills. A basin may consist of smaller basins that merge at river confluences, forming a hierarchical pattern. In North America, this is commonly called a watershed, though in other English-speaking places, "watershed" is used only in its original sense, that of the drainage divide line. Other terms for a drainage basin are catchment area, catchment basin, drainage area, river basin, water catchment, water basin, and impluvium. A drainage basin's boundaries are determined by watershed delineation, a common task in environmental engineering and science.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 稀有元素是指自然界中储量稀少（一般地壳丰度为100ppm以下）或分布稀散、很少富集成矿的元素。部分稀有元素常用来制造特种金属材料或特殊元件，如特种钢、合金、永久磁铁等，在飞机、火箭、汽车、原子能、半导体等工业领域属于关键性材料。代表性的稀有金属有铍、镓、铟、铼以及稀土金属等。
A trace element is a chemical element of a minute quantity, a trace amount, especially used in referring to a micronutrient, but is also used to refer to minor elements in the composition of a rock, or other chemical substance. In nutrition, trace elements are classified into two groups: essential trace elements, and non-essential trace elements. Essential trace elements are needed for many physiological and biochemical processes in both plants and animals. Not only do trace elements play a role in biological processes but they also serve as catalysts to engage in redox – oxidation and reduction mechanisms. Trace elements of some heavy metals have a biological role as essential micronutrients.
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View content license ↗ 冲积扇（英语：Alluvial fan）是山地河流流出谷口时，因坡度骤降、水道趋于开阔，导致水流速度减慢、搬运能力降低，挟带的泥沙砾石在谷口大量堆积而成的扇状地貌。这类地形广泛分布于干旱、半干旱或部分湿润与现代冰河地区的山麓地带。其面积因地而异，小至不足1平方公里，大可达20,000平方公里。 冲积扇的形成动力主要来自泥石流或间歇性、常流性的溪流；河流向下游进入平原后，亦可能进一步塑造出广阔的冲积平原。 除了地球，科学家也在火星与土卫六（泰坦）上发现明显的冲积扇地貌，证实了这些外星天体过去或现在存在流体冲刷地表的作用。在陆域现代冲积扇中，位于中国新疆的塔里木盆地沙漠冲积扇为全球规模最大的扇体。由于冲积扇上的河道极易频繁改道（节点改道），一旦发生洪水，往往容易造成严重的灾害，例如2008年印度的戈西河洪灾便是典型案例。
An alluvial fan is an accumulation of sediments that fans outwards from a concentrated source of sediments, such as a narrow canyon emerging from an escarpment. They are characteristic of mountainous terrain in arid to semiarid climates, but are also found in more humid environments subject to intense rainfall and in areas of modern glaciation. They range in area from less than 1 square kilometer (0.4 sq mi) to almost 20,000 square kilometers (7,700 sq mi). Alluvial fans typically form where a flow of sediment or rocks emerge from a confined channel and are suddenly free to spread out in many directions. For example, many alluvial fans form when steep mountain valleys meet a flat plain. The transition from a narrow channel to a wide open area reduces the carrying capacity of flow and results in deposition of sediments. The flow can take the form of infrequent debris flows like in a landslide, or can be carried by an intermittent stream or creek. The reduction of flow is key to the formation of alluvial fans.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 勘探是人们对土地或地表以下进行地质分析的过程。目的是确认土地下面是否存在矿物、化石、贵金属。 人们可以通过多种方法勘探地质情况，钻探就是其中之一。
Prospecting is the first stage of the geological analysis (followed by exploration) of a territory. It is the search for minerals, fossils, precious metals, or mineral specimens. It is also known as fossicking. Traditionally prospecting relied on direct observation of mineralization in rock outcrops or in sediments. Modern prospecting also includes the use of geologic, geophysical, and geochemical tools to search for anomalies which can narrow the search area. Once an anomaly has been identified and interpreted to be a potential prospect direct observation can then be focused on this area. In some areas a prospector must also stake a claim, meaning they must erect posts with the appropriate placards on all four corners of a desired land they wish to prospect and register this claim before they may take samples. In other areas publicly held lands are open to prospecting without staking a mining claim.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 古地磁学（或称古磁学），作为地磁学的一个分支，是研究史前地质、地磁场变化与强度的一门科学。专门研究古地磁学的地球物理学家称为古地磁学家。 该门学科研究的目的，主要在于得知地球形成时残留于岩层的磁场讯息，再配合其他资料来进行统计方法分析，可用来从事多种地球科学领域的研究。 岩石中留存的磁性，这些岩石包含磁铁矿和赤铁矿等含铁矿石。在岩石形成过程中，或由于岩浆沉积作用、结晶作用，或化学反应致使矿物颗粒中内部磁场被地球磁场磁化而造成岩石的磁性。测量岩石中“化石磁”的方向，就可能测定岩石形成时的古纬度和当时地极的位置。 古地磁学家为大陆漂移学说提供了强有力的科学论证，并将其升级为板块构造理论。
Paleomagnetism (occasionally palaeomagnetism) is the study of prehistoric Earth's magnetic fields recorded in rocks, sediment, or archeological materials. Geophysicists who specialize in paleomagnetism are called paleomagnetists. Certain magnetic minerals in rocks can record the direction and intensity of Earth's magnetic field at the time they formed. This record provides information on the past behavior of the geomagnetic field and the past location of tectonic plates. The record of geomagnetic reversals preserved in volcanic and sedimentary rock sequences (magnetostratigraphy) provides a time-scale that is used as a geochronologic tool. Evidence from paleomagnetism led to the revival of the continental drift hypothesis and its transformation into the modern theory of plate tectonics. Apparent polar wander paths provided the first clear geophysical evidence for continental drift, while marine magnetic anomalies did the same for seafloor spreading.
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View content license ↗ 土层（soil horizon）又称土壤层、土壤发生层、土壤化育层，是大致平行于土壤的层，其物理特性不同于上面和下面的层。地平线在大多数情况下由明显的物理特征（主要是颜色和纹理）来定义。这些可以以绝对术语（例如纹理的粒度分布）和相对于周围材料（即，比上面和下面的层位“更粗糙”或“更陡峭”）的术语描述。 层位（horizon）于复合词中简称层，是依土壤的特性与其年代的不同而将其分为若干层序，并建立形成其在地质年代的地位。土壤分化为明显的层位，主要是源自土壤—大气界面的影响，如空气，水，太阳辐射和植物材料。由于土壤的风化首先发生在表面并向下工作，最上层已经改变最多，而最深层最类似于原始母材料。 科学家经常挖一个大洞，称为土坑（有时几米深，大约一米宽），以暴露土壤层进行研究。 将一组层位从地面暴露于母岩的垂直部分称为土壤剖面。大多数土壤，特别是在温带气候下，符合类似的一般层位模式，在图表中通常表示为“理想”土壤。此外，许多亚热带和热带地区有土壤，如氧化物溶液或干旱与“理想”的土壤有非常不同的地平线，或根本没有地平线。
A soil horizon is a layer parallel to the soil surface whose physical, chemical and biological characteristics differ from the layers above and beneath. Horizons are defined in many cases by obvious physical features, mainly colour and texture. These may be described both in absolute terms (particle size distribution for texture, for instance) and in terms relative to the surrounding material, i.e. "coarser" or "sandier" or "darker" than the horizons above and below. The identified horizons are indicated with symbols, which are mostly used in a hierarchical way. Master horizons (main horizons) are indicated by capital letters. Suffixes, in form of lowercase letters and figures, further differentiate the master horizons. There are many different systems of horizon symbols in the world. No one system is more correct—as artificial constructs, their utility lies in their ability to accurately describe local conditions in a consistent manner. Due to the different definitions of the horizon symbols, the systems cannot be mixed.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 喀斯特地貌（英语：karst）又称为岩溶地貌、溶蚀地形、石灰岩地形，是具有溶蚀力的水对可溶性岩石（碳酸盐岩类、硫酸盐岩、卤盐岩）进行溶蚀等作用所形成的地表和地下形态的总称。水对可溶性岩石所进行的作用，统称为喀斯特作用。当雨水或者地下水与地面的碳酸盐类岩石接触时，就会有少量碳酸盐溶于水中。经过长时期的溶解侵蚀，形成了以地表岩层千沟万壑为标志的地表特征。在喀斯特地貌下往往存在地下河、溶洞等景象。 喀斯特地貌约占陆地面积的15%。中国是喀斯特面积最大、分布最广的国家，达344万平方千米，其中以贵州为中心的西南裸露型喀斯特地区是世界上面积最大、最集中连片分布区。 喀斯特地貌的地表崎岖、土壤十分贫瘠，不利农业发展，因此在云贵高原有“地无三里平，天无三日晴，人无三两银”的俗谚。但其千沟万壑的特色却十分受到观光客青睐。除了云贵高原以外，巴尔干半岛、尤卡坦半岛均有喀斯特地形的存在。
Karst () is a topography formed from the dissolution of soluble carbonate rocks such as limestone and dolomite. It is characterized by features like poljes above and drainage systems with sinkholes and caves underground. There is some evidence that karst may occur in more weathering-resistant rocks such as quartzite given the right conditions. Subterranean drainage may limit surface water, with few if any rivers or lakes. In regions where the dissolved bedrock is covered (perhaps by debris) or confined by one or more superimposed non-soluble rock strata, distinctive karst features may occur only at subsurface levels and can be totally missing above ground. The study of paleokarst (buried karst in the stratigraphic column) is important in petroleum geology because as much as 50% of the world's hydrocarbon reserves are hosted in carbonate rock, and much of this is found in porous karst systems.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 冰碛（法语：Moraine）是指现今或曾经被冰川覆盖的地区内的任何未固结的碎屑（浮土和岩石）的堆积物。冰碛由先前被冰川或冰盖夹带、运移的物质组成。
A moraine is any accumulation of unconsolidated debris (regolith and rock), sometimes referred to as glacial till, that occurs in both currently and formerly glaciated regions and that has been previously carried along by a glacier or ice sheet. It may consist of partly rounded particles ranging in size from boulders (in which case it is often referred to as boulder clay) down to gravel and sand, in a groundmass of finely divided clayey material sometimes called glacial flour. Lateral moraines are those formed at the side of the ice flow, and terminal moraines are those formed at the foot, marking the maximum advance of the glacier. Other types include ground moraines (till-covered areas forming sheets on flat or irregular topography) and medial moraines (formed where two glaciers meet).
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View content license ↗ 冰碛物是指在冰川作用下由侵蚀所形成的沉积物。由于未经分选，故颗粒大可至大石，小可至粉砂。可经成岩作用成为冰碛石。 冰碛物有不同的分类标准，如可分为原生矿床和次生矿床。
Till, or glacial till, is unsorted glacial sediment. Till is derived from the erosion and entrainment of material by the moving ice of a glacier. It is deposited some distance down-ice to form terminal, lateral, medial and ground moraines. Till is classified into primary deposits, laid down directly by glaciers, and secondary deposits, reworked by fluvial transport and other processes.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 海底扩张学说（英语：Seafloor spreading）是在大陆漂移学说的基础上所发展出的进阶地球地质活动学说。在各大洋的中央有一带状分布的中洋脊，这些带中洋脊是下方地幔软流层的出口。不断涌出的熔岩自中洋脊流出，冷却而成为刚性强的大洋地壳。大洋地壳不断的受到新由中洋脊涌出的熔岩所推挤而向两旁移动，使海面积扩大，同时大陆地壳受到推挤而分离。
Seafloor spreading, or seafloor spread, is a process that occurs at mid-ocean ridges, where new oceanic crust is formed through volcanic activity and then gradually moves away from the ridge.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 岩石圈（Lithosphere）位于地球的表层，薄而坚硬。岩石圈在软流圈之上，包含部分上地幔和地壳。地壳在地幔之上，由莫氏不连续面作为分界。根据板块构造学说，岩石圈并非整体一块，而是由许多板块组成。
A lithosphere is the rigid outermost rocky shell of a terrestrial planet or natural satellite. On Earth, it is composed of the crust and the lithospheric mantle, the topmost portion of the upper mantle that behaves elastically on time scales of up to thousands of years or more. The crust and upper mantle are distinguished on the basis of chemistry and mineralogy.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 软流圈（Asthenosphere）是地球地幔的一部分弱塑性变形区域，位于岩石圈的下面、中间圈的上面，其软流圈下界在地表以下80-200km深处。 岩石圈与软流圈的边界，定义在1300°C等温线。此线以上的岩石圈为刚性变形，此线以下的软流圈为黏滞变形。软流圈的下界没有一个确定定义，通常采用温度或者流变学的变形率。在某些地方（如大洋板块深俯冲）软流圈下界可深达700km。 地激波在软流圈的波速下降10%左右，形成一个低速区。这可能是由于软流圈存在部分熔融。大洋地壳下的岩石圈-软流圈边界比较浅（平均在60km深处），地激波在此会突然下降5-10%。在中洋脊，岩石圈-软流圈边界在大洋地壳下几千米处。 1914年-1915年，巴雷尔·约瑟夫发表8篇关于地壳均衡的系列研究文章，从力学角度（刚性和流变性）提出了岩石圈与软流圈的分野并给其命名。该词来源于希腊语单词asthenēs(weak)与单词sphere的组合；推测为塑性状态的超铁镁物质；软流圈以上的地幔顶部为坚硬的岩石，与地壳的岩石合称为岩石圈；因为板块构造论的地幔对流体的运动就是在软流圈中进行，岩石圈板块在软流圈之上受到对流体的驱动而飘移，故称软流圈。软流圈实现了地壳均衡。 虽然早在1926年，就有推测软流圈的存在，但软流圈的证实始于1960年5月22日智利地震。
The asthenosphere (from Ancient Greek ἀσθενός (asthenós) 'without strength') is the mechanically weak and ductile region of the upper mantle of Earth. It lies below the lithosphere, at a depth between c. 80 and 200 km (50 and 120 mi) below the surface, and extends as deep as 700 km (430 mi). However, the lower boundary of the asthenosphere is not well defined. The asthenosphere is almost solid, but a slight amount of melting (less than 0.1% of the rock) contributes to its mechanical weakness. More extensive decompression melting of the asthenosphere takes place where it wells upwards, and this is the most important source of magma on Earth. It is the source of mid-ocean ridge basalt (MORB) and of some magmas that erupt above subduction zones or in regions of continental rifting.
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View content license ↗ 转换断层（英语：Transform fault），又称为转形断层或错动型板块边界，是一系列沿着张裂型板块边界平行排列、把洋中脊走向切割为不同块段的一种大规模水平位移断层。转型断层形成的断裂带通常长达数千千米，宽约100到200千米，在海底表现为线形陡崖，两侧地形高度差可达两千米以上或更多。转型断层造成的板块水平位移量，如果以电磁勘探的结果和两侧的洋中脊轴比较，多者可以达到数百千米。 转换断层命名的原因是来自于其可以“转换”两个板块间运动方式的特质，也就是说，因为处于两个张裂形板块之间，所以无法固定为右移断层或左移断层的部分即为转换断层。板块间的相对运动，遇到转换断层之后，就有机会转变成另一种型式的相对运动。例如，一个转换断层可以使原本远离两段洋中脊的板块张裂，转换为拉近两段洋中脊的对向运动。
A transform fault or transform boundary, is a fault along a plate boundary where the motion is predominantly horizontal. It ends abruptly where it connects to another plate boundary, either another transform, a spreading ridge, or a subduction zone. A transform fault is a special case of a strike-slip fault that also forms a plate boundary. Most such faults are found in oceanic crust, where they accommodate the lateral offset between segments of divergent boundaries, forming a zigzag pattern. This results from oblique seafloor spreading where the direction of motion is not perpendicular to the trend of the overall divergent boundary. A smaller number of such faults are found on land, although these are generally better-known, such as the San Andreas Fault and North Anatolian Fault.
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View content license ↗ 地震仪是种能够侦测大地震动、探知地震发生、测绘地震波波形，并输出震波图的仪器。当地震发生时，人类除了肉体感知震动外，如果要藉科学了解地震波具体的震动方式、震动方向、振动周期，就得利用地震仪记录地震波。
A seismometer is an instrument that responds to ground displacement and shaking caused by quakes, volcanic eruptions, and explosions. They are usually combined with a timing device and a recording device to form a seismograph. The output of such a device—formerly recorded on paper (see picture) or film, now recorded and processed digitally—is a seismogram. Such data is used to locate and characterize earthquakes, and to study the internal structure of Earth.
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View content license ↗ 黄土一种浅黄或褐黄色的土，颗粒成分以粉土粒级为主（含量＞50%），物质粒径均一，具孔隙，无层理，疏松，垂直节理发育。富含碳酸钙,有时含硫酸盐或氯化物盐类，具有肉眼可见孔隙的第四纪陆相沉积物。黄土有时具有湿陷性。另外，其在矿物成分方面高度复杂，多达60多种矿物，包括岩浆岩、变质岩和沉积岩的矿物成分，而且与其中任何一种岩石的矿物成分都不相同。各地区黄土矿物成分大体相同，无论矿物种类还是百分含量都基本相似，并有比较多的易风化不稳定矿物。在化学成分中含量最多的是SiO2、Al2O3、CaO、Na2O，含有比较多的易溶盐类，主要是：氧化物、碳酸盐、硫酸盐、CaCO3,含量在10％-16％之间。在所含生物化石方面以耐旱草本植物花粉和耐干旱动物化石为主，而且含有喜暖湿的动植物化石。最早李希霍芬（1877年）对欧洲莱茵河流域及中国大陆的黄土提出的定义为：黄－褐色，含石灰质，以粉土为主的粉状土；没有层理，含陆生蜗牛，有垂直节理。历史方面，“黄土”一词，在中国古代文献中及民间就已出现。 西方国家在19世纪后期将德国莱茵河流域的黄色松散堆积物命名为“lœss”，由此音译出英（loess）、俄（Лёсс）等文，不同学者曾以不同观点提出黄土的定义。1933年奥布鲁切夫(Β.Α. Обручев)将没有层理的黄土称为原生黄土，并认为是风成成因的；次生黄土是其他各种成因形成的。由于冰川的活动，把四周的岩石研磨成非常微细、像面粉一样幼细的尘土。这些尘土干了以后，很容易被风带走，送到很远的地方去，并累积起来。当这些微细的泥土不断的沉积，可以堆成很高的山。 有时因淋洗作用较强而使粘粒明显往剖面下层移动，养分有的已流失而呈黄、黄棕或红棕色。多生成于丘陵地上之相对地形较安定、坡度起伏较缓和处。土壤多呈弱酸性，肥沃度偏低，须进行施肥管理及水土保持，才可做农牧用地。此土壤在新分类上属弱育土或淋溶土。 。
Loess (US: , UK: ; from German: Löss [lœs]) is a clastic, predominantly silt-sized sediment that is formed by the accumulation of wind-blown dust. Ten percent of Earth's land area is covered by loesses or similar deposits. Loess is a periglacial or aeolian (windborne) sediment, defined as an accumulation of 20% or less of clay with a balance of roughly equal parts sand and silt (with a typical grain size from 20 to 50 micrometers), often loosely cemented by calcium carbonate. Usually, they are homogeneous and highly porous and have vertical capillaries that permit the sediment to fracture and form vertical bluffs.
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View content license ↗ 加速规（英语：accelerometer），又称加速计、加速针、加速度传感器、重力加速度传感器等等，是一种测量物体固有加速度的设备。固有加速度是指物体相对于处于自由落体状态的观察者（即相对于惯性参考系）的加速度（速度的变化率, rate of change）。固有加速度与坐标加速度不同，坐标加速度是相对于给定坐标系的加速度，而坐标系可能在加速，也可能不在加速。举例来说，一个静止在地球表面的加速规，会测量出由于地球引力而直向上的加速度，约为g ≈ 9.81 m/s2。相比之下，处于自由下落状态的加速规所测量的加速度为零。 加速规在工业、消费性产品和科学领域有许多用途。高灵敏度加速规用于飞机和导弹的惯性导航系统。在无人航空载具中，加速规有助于稳定飞行。微机电系统 (MEMS) 加速计用于手持式电子设备，例如智能手机、相机和视频游戏控制器，以侦测这些设备的移动和方向。工业机械的震动则由加速规监测。地震仪是一种灵敏的加速规，用于监测地震等地面运动。 当两个或两个以上的加速规彼此协调时，它们可以量测在空间中的距离上的适当加速度差异，特别是重力，也就是重力场的梯度。重力梯度测量非常有用，因为绝对重力是一种微弱的效应，并且取决于当地的地球密度，而地球密度是相当多变的。 单轴加速规可沿着指定轴线测量加速度。多轴加速规同时侦测适当加速度的大小和方向，作为矢量量，通常以沿着不同轴定向的数个单轴加速规来实现。
An accelerometer is a device that measures the proper acceleration of an object. Proper acceleration is the acceleration (the rate of change of velocity) of the object relative to an observer who is in free fall (that is, relative to an inertial frame of reference). Proper acceleration is different from coordinate acceleration, which is acceleration with respect to a given coordinate system, which may or may not be accelerating. For example, an accelerometer at rest on the surface of the Earth will measure an acceleration due to Earth's gravity straight upwards of about g ≈ 9.81 m/s2. By contrast, an accelerometer that is in free fall will measure zero acceleration. Highly sensitive accelerometers are used in inertial navigation systems for aircraft and missiles. In unmanned aerial vehicles, accelerometers help to stabilize flight. Micromachined micro-electromechanical systems (MEMS) accelerometers are used in handheld electronic devices such as smartphones, cameras and video-game controllers to detect movement and orientation of these devices.
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View content license ↗ 地幔热柱又称热柱或地幔柱，是地球等行星地幔热对流的一种运动方式，是炽热的地幔物质从地球深部（通常位于核幔边界）上升到地表的热通道。在地球对流系统中，地幔柱作为物质与能量的主动上行通道，与代表下行通道的俯冲板片相互对应，共同维系着地壳、地幔与地核之间的热交换，并对地核与地幔起到整体冷却的作用。 板块构造学说主要探讨软流圈对流及岩石圈板块运移，难以单独解释夏威夷群岛等板块内部的剧烈火山活动。地幔柱模型阐释了小规模持续性的板内热点火山活动，也解释了地质历史上各时期规模巨大的洪流玄武岩喷发以及大火成岩省的形成机制。
A mantle plume is a proposed mechanism of convection within the Earth's mantle, hypothesized to explain anomalous volcanism. Because the plume head partially melts on reaching shallow depths, a plume is often invoked as the cause of volcanic hotspots, such as Hawaii or Iceland, and large igneous provinces such as the Deccan and Siberian Traps. Some such volcanic regions lie far from tectonic plate boundaries, while others represent unusually large-volume volcanism near plate boundaries.
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View content license ↗ 古登堡界面（古氏不连续面）是地核与地幔的交界。 1914年，德国地球物理学家宾诺·古登堡（Beno Gutenberg）发现地下2885千米处地震波的传播速度有明显变化，其中纵波的速度明显下降，横波完全消失。后来证实这里是地核与地幔的分界层。
The core–mantle boundary (CMB) of Earth lies between the planet's silicate mantle and its liquid iron–nickel outer core, at a depth of 2,891 km (1,796 mi) below Earth's surface. The boundary is observed via the discontinuity in seismic wave velocities at that depth due to the differences between the acoustic impedances of the solid mantle and the molten outer core. P-wave velocities are much slower in the outer core than in the deep mantle while S-waves do not exist at all in the liquid portion of the core. Recent evidence suggests a distinct boundary layer directly above the CMB possibly made of a novel phase of the basic perovskite mineralogy of the deep mantle named post-perovskite. Seismic tomography studies have shown significant irregularities within the boundary zone and appear to be dominated by the African and Pacific large low-shear-velocity provinces (LLSVP). The uppermost section of the outer core is thought to be about 500–1,800 K hotter than the overlying mantle, creating a thermal boundary layer.
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View content license ↗ 洋中脊（Mid-ocean ridge），又称洋脊、大洋中脊、中央海岭，是位于全球海中张裂性板块边界的一系列火山结构系统，也是世界中最长的山脉、海底山脉，长达80,000千米（49,700英里），其中连续的山脉长达65,000千米（40,400英里），与之相对应的地质结构是陆地上的裂谷（地堑），地幔的热对流在洋中脊中央处上升，岩浆在此涌出后，快速冷却为玄武岩，形成新的海洋地壳。
A mid-ocean ridge (MOR) is a seafloor mountain system formed by plate tectonics. It typically has a depth of about 2,600 meters (8,500 ft) and rises about 2,000 meters (6,600 ft) above the deepest portion of an ocean basin. This feature is where seafloor spreading takes place along a divergent plate boundary. The rate of seafloor spreading determines the morphology of the crest of the mid-ocean ridge and its width in an ocean basin. The production of new seafloor and oceanic lithosphere results from mantle upwelling in response to plate separation. The melt rises as magma at the linear weakness between the separating plates, and emerges as lava, creating new oceanic crust and lithosphere upon cooling. The first discovered mid-ocean ridge was the Mid-Atlantic Ridge, which is a spreading center that bisects the North and South Atlantic basins; its location was the reason for the name "mid-ocean ridge". Most oceanic spreading centers are not in the middle of their hosting ocean basins, but are traditionally called mid-ocean ridges regardless.
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View content license ↗ 在物理学中，衰减（英语：attenuation或extinction）是指通量在介质中随着传播而逐渐损耗强度。例如阳光在穿过墨镜时衰减，X射线会在铅中衰减，光和声音会在水和空气当中以不同衰减率衰减。
In physics, attenuation – colloquially, damping – is the gradual loss of flux intensity through a medium. For instance, dark glasses attenuate sunlight, lead attenuates X-rays, and water and air attenuate both light and sound at variable attenuation rates. Hearing protectors help reduce acoustic flux from flowing into the ears. This phenomenon is called acoustic attenuation and is measured in decibels (dBs). In electrical engineering and telecommunications, attenuation affects the propagation of waves and signals in electrical circuits, in optical fibers, and in air. Electrical attenuators and optical attenuators are commonly manufactured components in this field.
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View content license ↗ 品质因子或Q因子是物理及工程中的无量纲参数，是表示振子阻尼性质的物理量，也可表示振子的共振频率相对于带宽的大小， 高Q因子表示振子能量损失的速率较慢，振动可持续较长的时间，例如一个单摆在空气中运动，其Q因子较高，而在油中运动的单摆Q因子较低。高Q因子的振子一般其阻尼也较小。
In physics and engineering, the quality factor or Q factor is a dimensionless parameter that describes how underdamped an oscillator or resonator is. Resonators with high quality factors have low damping, so that they ring or vibrate longer. For example, a pendulum suspended from a precision bearing, oscillating in air, has a high Q, while a pendulum immersed in oil has a low Q. There are two definitions of Q that give numerically similar, but not identical, results. The more general definition is the ratio of the initial energy stored in the resonator to the energy lost in one radian of the cycle of oscillation. An alternative definition of Q factor, more applicable to high Q oscillators, is the ratio of a resonator's centre frequency to its bandwidth when subject to an oscillating driving force.
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View content license ↗ 化学元素丰度（英语：Chemical element abundance）是指在给定环境中某化学元素相对于其他所有元素含量多寡的比值。丰度可以是质量的比值或是莫尔数（气体的原子数量比值或是分子数量比值），或是容积比值。在混合气体中测量气体容积比值是表示丰度的常用方法，对混合的理想气体（相对于是低密度和低压的气体）这与莫耳数相当一致。 例如，氧元素在水中的质量比是89%，意思是水的质量和氧元素的质量的比值，但氧在水中的莫尔比值只有33%，因为在水的莫尔数中只有三分之一是氧原子。在整个宇宙中，比如像木星这样的巨大的气体行星中，氢和氦的质量丰度比值分别是74%和23~25%，但是摩尔（原子）比值却高达92%和8%。但是，因为氢是双原子分子，而氦在木星外层的大气环境下只是单原子分子，以分子的摩尔数来比较，在木星大气层中氢的丰度是86%，而氦的丰度是13%。 本文提到的丰度多数都是质量百分比。
The abundance of the chemical elements is a measure of the occurrences of the chemical elements relative to all other elements in a given environment. Abundance is measured in one of three ways: by mass fraction (in commercial contexts often called weight fraction), by mole fraction (fraction of atoms by numerical count, or sometimes fraction of molecules in gases), or by volume fraction. Volume fraction is a common abundance measure in mixed gases such as planetary atmospheres, and is similar in value to molecular mole fraction for gas mixtures at relatively low densities and pressures, and ideal gas mixtures. Most abundance values in this article are given as mass fractions. The abundance of chemical elements in the universe is dominated by the large amounts of hydrogen and helium which were produced during Big Bang nucleosynthesis. Remaining elements, making up only about 2% of the universe, were largely produced by supernova nucleosynthesis.
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View content license ↗ 贝切定律（英文；Birch's law)，是美国地球物理学家弗朗西斯·贝切于1961年建立的，指出在平均原子量为 M a v g {\displaystyle M_{\mathrm {avg} }} 的岩石和矿物中，弹性波传播速度 v p {\displaystyle v_{p}} 与密度 ρ {\displaystyle \rho } 成线性关系。其数学式为： v p = a ( M a v g ) + b ρ , {\displaystyle v_{p}=a(M_{\mathrm {avg} })+b\rho ,} 其中 a ( x ) {\displaystyle a(x)} 为某类函数， b {\displaystyle b} 为常数。
Birch's law, discovered by the geophysicist Francis Birch, establishes a linear relation between compressional wave velocity vp and density ρ {\displaystyle \rho } of rocks and minerals: v p = a ( M ¯ ) + b ρ {\displaystyle v_{\mathrm {p} }=a({\bar {M}})+b\rho } where M ¯ {\displaystyle \,{\bar {M}}\,} is the mean atomic mass in formula units and a ( x ) {\displaystyle \,a(x)\,} is an empirical function determined by experiment.
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View content license ↗ 亚当–威廉姆斯方程是指一个用来确定密度的方程。该方程常用于确定地震波的速度与地球内部密度之间的关系。通过岩石的平均密度和P波、S波的速度的函数分布，它可以预测地球密度随深度的关系。该方程的模型假定地球是对称的、均匀的球形，并且处于流体静力的平衡中。该方程实际上也可以应用于具有该性质的球壳。它被认为是是重要地球内部模型之一，例如初步地球参考模型。
The Adams–Williamson equation, named after Leason H. Adams and E. D. Williamson, is an equation used to determine density as a function of radius, more commonly used to determine the relation between the velocities of seismic waves and the density of the Earth's interior. Given the average density of rocks at the Earth's surface and profiles of the P-wave and S-wave speeds as function of depth, it can predict how density increases with depth. It assumes that the compression is adiabatic and that the Earth is spherically symmetric, homogeneous, and in hydrostatic equilibrium. It can also be applied to spherical shells with that property. It is an important part of models of the Earth's interior such as the Preliminary reference Earth model (PREM).
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 拜耳莱定律（英语：Byerlee's law），是描述地壳发生地质断层裂纹所产生的切应力和正向应力(normal stress)之间关系的函数： τ = S 0 + μ ( σ n − P f ) {\displaystyle \tau =S_{0}+\mu (\sigma _{n}-P_{f})} 其中： τ {\displaystyle \tau } 是切应力； σ n {\displaystyle \sigma _{n}} 是正向应力；S是材料的凝聚或内强度；P是岩石内的孔隙流动压力，在小范围内，它是一常数，而使岩石性能减弱。
In rheology, Byerlee's law, also known as Byerlee's friction law concerns the shear stress (τ) required to slide one rock over another. The rocks have macroscopically flat surfaces, but the surfaces have small asperities that make them "rough." For a given experiment and at normal stresses (σn) below about 2000 bars (200 MPa) the shear stress increases approximately linearly with the normal stress (τ = 0.85 σn, where τ and σn is in units of MPa) and is highly dependent on rock type and the character (roughness) of the surfaces, see Mohr-Coulomb friction law. Byerlee's law states that with increased normal stress the required shear stress continues to increase, but the rate of increase decreases (τ = 0.5 + 0.6σn), where τ and σn are in units of MPa, and becomes nearly independent of rock type. The law describes an important property of crustal rock, and can be used to determine when slip along a geological fault takes place. The law is named after the American geophysicist James Byerlee, who derived it experimentally in 1978.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 海底模拟反射面（英语：bottom simulating reflectors) 是在地震反射剖面上一种浅层的地震反射面，其特征在于其反射形状类似于海底反射面。 但它的反射极性与海底反射极性相反，并且经常与主要反射层理交叉。
Bottom simulating reflectors (BSRs) are, on seismic reflection profiles, shallow seismic reflection events, characterized by their reflection geometry similar to seafloor bathymetry. They have, however, the opposite reflection polarity to the seabed reflection, and frequently intersect the primary reflections.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 地温梯度（英语：Geothermal gradient）是与地球内部深度增加相关的每单位深度的温度升高变化率。在世界上大部分远离板块构造的地区里，接近地表附近的地温梯度是每公里深度为25–30 °C/km（或 72-87 °F/英里）。严格来说，地热必然是指地球，但概念可能适用于其他行星。借由行星体跟踪梯度的线被称为地球和其他地球行星上的"地热"（geotherm）。在月球上，它被称为"月热"（selenotherm）。 地球的内部热量来自行星形成时的沉积物的剩余热量，通过放射性衰变产生的热量以及其他来源的热量的组合。地球中主要的发热同位素是钾-40，铀-238，铀-235和钍-232。在行星的中心，温度可以高达7000 K，和压力可能会达到360 GPA（360万个大气压）。
Geothermal gradient is the rate of change in temperature with respect to increasing depth in Earth's interior. As a general rule, the crust temperature rises with depth due to the heat flow from the much hotter mantle; away from tectonic plate boundaries, temperature rises with depth at a rate of about 25–30 °C/km (72–87 °F/mi) near the surface in the continental crust. However, in some cases the temperature may drop with increasing depth, especially near the surface, a phenomenon known as inverse or negative geothermal gradient. The effects of weather and climate are shallow, only reaching a depth of roughly 10–20 m (33–66 ft). Strictly speaking, geo-thermal necessarily refers to Earth, but the concept may be applied to other planets. In SI units, the geothermal gradient is expressed in degree celsius per kilometre (°C/km), kelvin per kilometre (K/km), or millikelvin per metre (mK/m); these are all equivalent.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
View content license ↗ 惯性波，也称为惯性振荡、惯性内波，是一种可能出现在旋转流体中的机械波。与通常在海滩或浴缸中看到的表面引力波不同，惯性波流过流体内部，而不是表面。与任何其他类型的波一样，惯性波是由恢复力引起的，并以其波长和频率为特征。因为惯性波的恢复力是科里奥利力，它们的波长和频率以一种特殊的方式相关。惯性波是横向的。最常见的是在大气、海洋、湖泊和实验室实验中观察到它们。罗斯贝波、地转流和地转风是惯性波的例子。惯性波也可能存在于旋转地球的熔融核心中。
Inertial waves, also known as inertial oscillations, are a type of mechanical wave possible in rotating fluids. Unlike surface gravity waves commonly seen at the beach or in the bathtub, inertial waves flow through the interior of the fluid, not at the surface. Like any other kind of wave, an inertial wave is caused by a restoring force and characterized by its wavelength and frequency. Because the restoring force for inertial waves is the Coriolis force, their wavelengths and frequencies are related in a peculiar way. Inertial waves are transverse. Most commonly they are observed in atmospheres, oceans, lakes, and laboratory experiments. Rossby waves, geostrophic currents, and geostrophic winds are examples of inertial waves. Inertial waves are also likely to exist in the molten core of the rotating Earth.
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Wikipedia contributors · Retrieved2026-10-04 · CC BY-SA 4.0. Introductions were extracted as plain text and shortened. Language versions may emphasize different aspects.For concept reference; consult the original standards for authoritative requirements.
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