共查询到18条相似文献，搜索用时 109 毫秒
1.
青藏高原的隆升由印度-欧亚板块的碰撞而驱动,其生长演化,特别是从内到外的扩展机制仍尚存争议。祁连山地处青藏高原向东北扩展的前缘位置,其地壳结构与各向异性对于理解青藏高原向北扩展的生长机制具有重要意义。祁连山中部是青藏高原东北缘地壳遭受挤压强烈变形的区域,已有的研究已经揭示出地壳内部非耦合不均匀变形的几何行为,揭露其对应机制是亟待探索的前沿科学问题。此前该区域的各向异性研究大多基于面状台网数据,台站间距大,无法反映横跨祁连山地壳各向异性的精细变化。为此,本研究选用一条密集线性地震台阵,使用H-κ-c叠加方法,得到了横过祁连山中部的地壳厚度,泊松比以及地壳各向异性的横向变化。结果显示,在中祁连以及南祁连北部地壳厚度最大,平均泊松比最低,反映了地壳加厚过程中铁镁质下地壳的丢失以及长英质中上地壳的水平缩短。此外,偏长英质成分的泊松比值也不支持地壳流在该区域存在。在祁连山内部,地壳各向异性快波的偏振方向与地壳向外扩展方向一致,而与地幔各向异性快波方向近垂直,揭示了壳幔变形可能是解耦的。而在地壳较薄的南祁连和北祁连南部区域,快波方向与古缝合线的走向一致,说明早古生代的构造格局仍对现今的祁连山缩短隆升产生影响。 相似文献
2.
通过对青藏高原东缘大地电磁测深实测资料的分析,结合区域地质、重、磁、大地电磁和地震资料,文章对青藏高
原东缘的深部构造、壳内高导层、电性结构与矿产的关系进行了研究。结果表明,重力计算中的莫霍面是由诸多高低变化
电阻组成的一个界面,莫霍面之上容易形成壳内高导体;在20 km深度左右存在电阻率变化界面,为上下地壳界面的反映。
电性和Vs研究表明,在地幔柱发育地区,地壳厚度减薄了15 km左右。区内诸如金沙江-红河断裂、鲜水河断裂等深大断裂
带已经深达莫霍面,成为各块体或成矿带的边界,控制了岩体和壳内高导体的分布。进而探讨了贡嘎山壳幔高导体的成因
以及区内地幔柱与矿产的关系。 相似文献
3.
印度大陆板块北向碰撞及俯冲导致的青藏高原快速隆升,使得青藏高原内部的物质组成及构造演化更为复杂,其中之一高原内部的低速层分布特征及其构造成因尚不明确.藏北高原中部的班公湖—怒江缝合带两侧宽频带地震观测程度较高,为调查班公湖—怒江缝合带两侧低速层分布特征提供了良好的客观条件.本文选取了INDEPTH-III项目布置在班公怒江缝合带两侧的宽频带地震台站记录的远震数据,开展接收函数分析,通过时频域相位滤波提高信噪比,并利用接收函数复谱比非线性反演方法得到了台站下方一维S波速度结构.反演结果表明班公湖—怒江缝合带两侧地壳中低速层广泛分布,且横向不连续,埋深在20～40 km之间,部分地区在0～15 km的上地壳也出现低速层.上地壳内的低速层分布特征主要与地表区域构造及沉积层分布相关;中下地壳内的低速层分布不仅受到了地体边界的约束,且可能与后期青藏高原整体隆升相关. 相似文献
4.
《地球学报》2021,(1)
印度大陆板块北向碰撞及俯冲导致的青藏高原快速隆升,使得青藏高原内部的物质组成及构造演化更为复杂,其中之一高原内部的低速层分布特征及其构造成因尚不明确。藏北高原中部的班公湖—怒江缝合带两侧宽频带地震观测程度较高,为调查班公湖—怒江缝合带两侧低速层分布特征提供了良好的客观条件。本文选取了INDEPTH-Ⅲ项目布置在班公怒江缝合带两侧的宽频带地震台站记录的远震数据,开展接收函数分析,通过时频域相位滤波提高信噪比,并利用接收函数复谱比非线性反演方法得到了台站下方一维S波速度结构。反演结果表明班公湖—怒江缝合带两侧地壳中低速层广泛分布,且横向不连续,埋深在20～40 km之间,部分地区在0～15 km的上地壳也出现低速层。上地壳内的低速层分布特征主要与地表区域构造及沉积层分布相关;中下地壳内的低速层分布不仅受到了地体边界的约束,且可能与后期青藏高原整体隆升相关。 相似文献
5.
为了调查羌塘盆地中部壳内低速层分布特征,对布设在羌塘盆地的TITAN-I宽频带地震台站所记录的远震波形数据进行接收函数分析,并引入时频域相位滤波技术改善接收函数信噪比,反演得到各台站下方100 km深度范围内的一维S波速度结构.结果表明,时频域相位滤波方法能够显著提高信噪比;羌塘盆地Moho深度为58±6 km,具有较高的泊松比值;中下地壳壳内低速层广泛分布,横向不连续,埋深在20~30 km,层厚6~12 km,剪切波速度为3.4±0.1 km/s;部分地区在埋深为10 km的中上地壳存在一层厚约4 km的低速薄层.羌塘盆地中下地壳壳内低速层是由于上涌的深部软流圈物质与下地壳发生大范围的接触,造成壳内及上地幔部分熔融引起的. 相似文献
6.
Xiaojun WANG Yong SONG Baoli BIAN Junmeng ZHAO Heng ZHANG Maodu YAN Shunping PEI Qiang XU Shuaijun WANG Hongbing LIU Changhui JU 《地学前缘》2021,28(6):235-255
我们已完成了穿越准噶尔盆地及其周边地区的I-I、II-II、III-III、IV-IV和额敏—哈密剖面5条综合地球物理剖面。通过综合研究,初步了解准噶尔盆地及邻近地区的地球动力学问题:准噶尔盆地基底由北部的乌伦古地体和南部的玛纳斯地体组成。两者的分界为西西北方向的滴水泉—三个泉缝合线。其西部与北东向Dalbutte缝合带相连,东部与北西向的Cranamary缝合带相连。准噶尔盆地北部的乌伦古地体基底为双层构造,上层为泥盆系和下石炭统组成的褶皱基底,大致表现为北厚(3~5 km)、南薄(1~2 km)。缝合线以南的玛纳斯地体为单层基底,即新元古代结晶基底。准噶尔盆地地壳厚度为44~52 km,北薄南厚。周边山区地壳厚度高于盆地地区。盆地及邻近地区地壳分为上、中、下层,并且中地壳一般较薄。盆地地区的地壳存在多条深断裂。南北方向发育了6条主要深断裂,分别为红车、德伦山、石溪、呼图壁、彩南和阜康。这些断层倾角较大,向上延伸至上地壳下部,向下切入地壳基底界面。壳内水平构造和构造面无明显垂向断层,似有“开放断层”特征。这些断层是上地幔物质挤入地壳的良好通道。此外,该地区还有两条主要的横向深断层。一是北西西走向的滴水泉—三个泉深断裂,它向南倾斜,具有逆断层性质,可能会破坏滴水泉—三个泉缝合带。另一条是近东西向的昌吉—玛纳斯深断裂,向南倾斜,主要发育在中下地壳,具有逆断层性质。这些深断裂对盆地构造发育具有一定的控制作用。准噶尔盆地西部的莫霍面基本连续地延伸到了天山的莫霍面,并且后者的莫霍面深度明显大于前者。但是,盆地东部的莫霍面与博格达山脉的莫霍面并不连续。前者以叠加关系延伸到后者之下,表明盆地东部的地壳向博格达山脉俯冲。这有助于解释天山东部构造活动相对减弱而博格达山脉向北推高的构造地貌现象。周边准噶尔盆地具有挤压盆地-山地构造耦合格局,尤其是南部边界东部博格达—准东盆地的山地-盆地构造耦合。现在将准噶尔盆地与吐哈盆地分开的博格达山脉是年轻的、仍在上升的山脉。博格达山的隆升是印支运动以来多次推覆造山运动的反映,其现貌是新近纪以来新构造运动的结果。准噶尔盆地盖层发育经历了3个阶段:与天山和松潘—甘孜造山带形成有关的二叠纪—三叠纪前陆盆地阶段,区域压缩较弱的侏罗纪—早始新世陆内坳陷阶段,以及新近纪晚期以来与天山抬升有关的活化前陆盆地阶段。 相似文献
7.
相位加权叠加方法在探测鄂尔多斯东南缘地壳结构中的应用 总被引：2，自引：0，他引：2
本文利用在鄂尔多斯东南缘地区宽频带流动地震台阵记录的远震数据,提取各台站的接收函数,并利用相位加权方
法进行单台多震叠加、H -κ叠加以及共转换点叠加,获得了研究区莫霍过渡带的深度及其变化趋势。研究结果显示,莫霍的
深度由鄂尔多斯块体往东南方向逐渐变浅,在不同区域莫霍具有不同的特征：鄂尔多斯的莫霍深度在42~38 km;渭河-山
西地堑的莫霍出现约3 km的上隆;熊耳-伏牛山的莫霍深度在35~33 km;河淮盆地的莫霍形态比较复杂。相位加权叠加方
法能有效地压制相关性不好的噪音,在部分受噪音及沉积层多次波干扰的台站记录中,对突出莫霍的转换波Ps震相有很大
的帮助。 相似文献
8.
GAO Rui ZHOU Hui GUO Xiaoyu LU Zhanwu LI Wenhui WANG Haiyan LI Hongqiang XIONG Xiaosong HUANG Xingfu XU Xiao 《地学前缘》2021,28(5):320-336
印度板块与亚洲板块的碰撞使喜马拉雅-青藏高原隆升,地壳增厚和生长扩展。探测青藏高原深部结构,揭露两个大陆如何碰撞,碰撞如何使大陆变形的过程,是全球关切的科学奥秘。深地震反射剖面探测是打开这个科学奥秘的最有效途径之一。20多年来,运用这项高技术探测到青藏高原巨厚地壳的精细结构,攻克了难以得到下地壳和Moho清晰结构的技术瓶颈,揭露了陆陆碰撞过程。本文在探测研究成果基础上,从青藏高原南北-东西对比,再到高原腹地,系统地综述了青藏高原之下印度板块与亚洲板块碰撞-俯冲的深部行为。印度地壳在高原南缘俯冲在喜马拉雅造山带之下,亚洲板块的阿拉善地块岩石圈在北缘向祁连山下俯冲,祁连山地壳向外扩展,塔里木地块与高原西缘的西昆仑发生面对面的碰撞,在高原东缘发现龙日坝断裂而不是龙门山断裂是扬子板块的西缘边界,高原腹地Moho 薄而平坦,岩石圈伸展垮塌。多条深反射剖面揭露了在雅鲁藏布江缝合带下印度板块与亚洲板块碰撞的行为,印度地壳不仅沿雅鲁藏布江缝合带存在由西向东的俯冲角度变化,而且其向北行进到拉萨地体内部的位置也不同。在缝合带中部,显示印度地壳上地壳与下地壳拆离,上地壳向北仰冲,下地壳向北俯冲,并在俯冲过程发生物质的回返与构造叠置,使印度地壳减薄,喜马拉雅地壳加厚。俯冲印度地壳前缘与亚洲地壳碰撞后沉入地幔,处于亚洲板块前缘的冈底斯岩基与特提斯喜马拉雅近于直立碰撞,冈底斯下地壳呈部分熔融状态,近乎透明的弱反射和局部出现的亮点反射,以及近于平的Moho都反映出亚洲板块南缘的伸展构造环境。 相似文献
9.
陆陆碰撞过程是板块构造缺失的链条。印度板块与亚洲板块的碰撞造就了喜马拉雅造山带和青藏高原的主体。然而,人们对印度板块在大陆碰撞过程中的行为尚不了解。如大陆碰撞及其碰撞后的大陆俯冲是如何进行的、印度板块是俯冲在青藏高原之下还是回转至板块上部(喜马拉雅造山带内)以及两者比例如何,这些仍是亟待解决的问题。印度板块低角度沿喜马拉雅主逆冲断裂(MHT)俯冲在低喜马拉雅和高喜马拉雅之下已经被反射地震图像很好地揭示。然而,关于MHT如何向北延伸,前人的研究仅获得了分辨率较低的接收函数图像。因而,MHT和雅鲁藏布江缝合带之间印度板块的俯冲行为仍是一个谜。喜马拉雅造山楔增生机制,也就是印度地壳前缘的变形机制,反映出物质被临界锥形逆冲断层作用转移到板块上部,或是以韧性管道流的样式向南溢出。在本次研究中,我们给出在喜马拉雅造山带西部地区横过雅鲁藏布江缝合带的沿东经81.5°展布的高分辨率深地震反射剖面,精细揭示了地壳尺度结构构造。剖面显示,MHT以大约20°的倾斜角度延伸至大约60 km深度,接近埋深为70~75 km的Moho面。越过雅鲁藏布江缝合带运移到北面的印度地壳厚度已经不足15 km。深地震反射剖面还显示中地壳逆冲构造反射发育。我们认为,伴随着印度板块俯冲,地壳尺度的多重构造叠置作用使物质自MHT下部的板块向其上部板块转移,这一过程使印度地壳厚度减薄了,同时加厚了喜马拉雅地壳。 相似文献
10.
印度板块与亚洲板块的碰撞使喜马拉雅-青藏高原隆升,地壳增厚并生长扩展。探测青藏高原深部结构,揭露两个大陆如何碰撞以及碰撞如何使大陆变形的过程,是对全球关切的科学奥秘的探索。深地震反射剖面探测是打开这个科学奥秘的最有效途径之一。二十多年来,运用这项高技术探测到青藏高原巨厚地壳的精细结构,攻克了难以得到下地壳和Moho面信息的技术瓶颈,揭露了陆-陆碰撞过程。本文在探测研究成果的基础上,从青藏高原南北-东西对比,再到高原腹地,系统地综述了青藏高原之下印度板块与亚洲板块碰撞-俯冲的深部行为。印度地壳在高原南缘俯冲在喜马拉雅造山带之下,亚洲板块的阿拉善地块岩石圈在北缘向祁连山下俯冲,祁连山地壳向外扩展,塔里木地块与高原西缘的西昆仑发生面对面的碰撞,在高原东缘发现龙日坝断裂(而不是龙门山断裂)是扬子板块的西缘边界,高原腹地Moho面厚度薄而平坦,岩石圈伸展垮塌。多条深反射剖面揭露了在雅鲁藏布江缝合带下印度板块与亚洲板块碰撞的行为,不仅沿雅鲁藏布江缝合带走向印度地壳俯冲行为存在东西变化,而且印度地壳向北行进到拉萨地体内部的位置也不同。在缝合带中部,研究显示印度地壳上地壳与下地壳拆离,上地壳向北仰冲,下地壳向北俯冲,并在俯冲过程中发生物质的回返与构造叠置,这导致印度地壳减薄,喜马拉雅地壳加厚。俯冲印度地壳前缘与亚洲地壳碰撞后沉入地幔,处于亚洲板块前缘的冈底斯岩基与特提斯喜马拉雅近于直立碰撞,冈底斯下地壳呈部分熔融状态,近乎透明的弱反射和局部出现的亮点反射以及近于平的Moho面都反映出亚洲板块南缘处于伸展构造环境。 相似文献
11.
Crustal structure of the Paleozoic Kunlun orogeny from an active-source seismic profile between Moba and Guide in East Tibet, China 总被引：13，自引：0，他引：13
Zhongjie Zhang Simon Klemperer Zhiming Bai Yun Chen Jiwen Teng 《Gondwana Research》2011,19(4):994-1007
We herein present a new seismic refraction/wide-angle reflection profile that crosses the Songpan–Ganzi terrane, the Animaqing suture zone and the eastern Kunlun mountains (comprised of the South Kunlun and Middle Kunlun blocks separated by the Middle Kunlun fault). The profile is 380 km long and extends from Moba to Guide in eastern Tibet. The crustal thickness is about 62 km under the Songpan–Ganzi terrane, 62–64 km under the South Kunlun, and 60 km under the Middle Kunlun block. The Songpan–Ganzi flysch seems to be present up to a depth of 15 km south of the Animaqing suture zone, and up to a depth of 10 km in the Middle Kunlun block, with thicknesses elsewhere that depend on assumptions about the likely lithologies. The profile exhibits clear lateral variations both in the upper and lower crust, which are indicative of different crustal blocks juxtaposed by the Kunlun fault system. Whether or not the Songpan–Ganzi flysch was originally deposited on oceanic crust, at the longitude of our profile (100°E) it is now underlain by continental crust, and the presence of continental crust beneath the Songpan–Ganzi terrane and of a continental arc under the South Kunlun block suggest Paleozoic continent–continent arc collision in the eastern Kunlun Mountains. Comparison of crustal velocity columns from all wide-angle seismic profiles across the eastern Kunlun mountains indicates a remarkable west-to-east change in the Moho topography across the Kunlun fault system (15–20 km Moho step at 95°E, but only 2–5 km along our profile at 100°E). Lower-crustal thickness of the Kunlun terranes is rather uniform, about 35 km, from 80°–95°E, which suggests that similar thrust-thickening processes have played a role where the Qaidam Basin abuts the Kunlun fault, but thins to 20–25 km at 100°E, east of the Qaidam Basin. The increased crustal thickness from 93° to 98°E compared to that at 100°E may be due to the differences in the thickness of the crust of the two plates before their collision, and/or largely achieved by thickening of the lower crust, perhaps indicating a crustal flow mechanism operating more strongly in the western region. 相似文献
12.
Seismological Evidences for the Multiple Incomplete Crustal Subductions in Himalaya and Southern Tibet 总被引：3，自引：0，他引：3
SEISMOLOGICAL EVIDENCES FOR THE MULTIPLE INCOMPLETE CRUSTAL SUBDUCTIONS IN HIMALAYA AND SOUTHERN TIBET 相似文献
13.
Crustal structure of the Kaapvaal craton and its significance for early crustal evolution 总被引：1，自引：0，他引：1
High-quality seismic data obtained from a dense broadband array near Kimberley, South Africa, exhibit crustal reverberations of remarkable clarity that provide well-resolved constraints on the structure of the lowermost crust and Moho. Receiver function analysis of Moho conversions and crustal multiples beneath the Kimberley array shows that the crust is 35 km thick with an average Poisson's ratio of 0.25. The density contrast across the Moho is 15%, indicating a crustal density about 2.86 gm/cc just above the Moho, appropriate for felsic to intermediate rock compositions. Analysis of waveform broadening of the crustal reverberation phases suggests that the Moho transition can be no more than 0.5 km thick and the total variation in crustal thickness over the 2400 km2 footprint of the array no more than 1 km. Waveform and travel time analysis of a large earthquake triggered by deep gold mining operations (the Welkom mine event) some 200 km away from the array yield an average crustal thickness of 35 km along the propagation path between the Kimberley array and the event. P- and S-wave velocities for the lowermost crust are modeled to be 6.75 and 3.90 km/s, respectively, with uppermost mantle velocities of 8.2 and 4.79 km/s, respectively. Seismograms from the Welkom event exhibit theoretically predicted but rarely observed crustal reverberation phases that involve reflection or conversion at the Moho. Correlation between observed and synthetic waveforms and phase amplitudes of the Moho reverberations suggests that the crust along the propagation path between source and receiver is highly uniform in both thickness and average seismic velocity and that the Moho transition zone is everywhere less than about 2 km thick. While the extremely flat Moho, sharp transition zone and low crustal densities beneath the region of study may date from the time of crustal formation, a more geologically plausible interpretation involves extensive crustal melting and ductile flow during the major craton-wide Ventersdorp tectonomagmatic event near the end of Archean time. 相似文献
14.
本文据中-法合作期间的地震广角反射资料阐述了青藏高原的深部地壳结构及构造特征,结合地表地质现象探讨了高原的形成机制。资料表明青藏高原上、下地壳分别增厚一倍左右,最厚处达75km。它是由来自北侧并逐渐向南推挤的强大水平力,使该区地壳与其南部的印度地块相碰并受其阻挡,在经向水平挤压力的长期作用下,该区地壳终于从喜马拉雅运动早期开始,在经向上因地壳片段的褶皱和叠覆而缩短,在垂向上急剧增厚和抬升而形成高原。这是构造力与重力联合作用的结果。 相似文献
15.
Chi-Chia Tang Lupei Zhu Chau-Huei Chen Ta-Liang Teng 《Journal of Asian Earth Sciences》2011,41(6):549-570
The Chaochou Fault, a major geological boundary in southern Taiwan is considered to be a part of the convergent plate boundary between the Eurasia Plate and the Philippine Sea Plate. We applied the Common Conversion Point stacking technique to teleseismic radial receiver functions and obtained Moho variation and crustal structure across the Chaochou Fault. In the Eurasia Plate to its west, the Moho depth is about 37 km and the crust is subducting to the east beneath the Philippine Sea Plate with a dip angle of about 30° between the Backbone Belt and the Tananao Schist. In the Philippine Sea Plate, the Moho depth is about 17 km. The Longitudinal Valley marks the collision boundary between the Eurasia Plate and the Philippine Sea Plate. The results suggest that the depth extent of the Chaochou Fault is about 30–35 km and the fault becomes a “shallow-angle” thrust fault at depth. The Common Conversion Point image also shows several bending interfaces of velocity contrast in the crust. We proposed a simple model to explain the Philippine Sea Plate and Eurasia Plate collision process and the observed crustal deformations. 相似文献
16.
Claus Prodehl 《Tectonophysics》1981,80(1-4):255-269
The crustal structure of the central European rift system has been investigated by seismic methods with varying success. Only a few investigations deal with the upper-mantle structure. Beneath the Rhinegraben the Moho is elevated, with a minimum depth of 25 km. Below the flanks it is a first-order discontinuity, while within the graben it is replaced by a transition zone with the strongest velocity gradient at 20–22 km depth. An anomalously high velocity of up to 8.6 km/s seems to exist within the underlying upper mantle at 40–50 km depth. A similar structure is also found beneath the Limagnegraben and the young volcanic zones within the Massif Central of France, but the velocity within the upper mantle at 40–50 km depth seems to be slightly lower. Here, the total crustal thickness reaches only 25 km. The crystalline crust becomes extremely thin beneath the southern Rhônegraben, where the sediments reach a thickness of about 10 km while the Moho is found at 24 km depth. The pronounced crustal thinning does not continue along the entire graben system. North of the Rhinegraben in particular the typical graben structure is interrupted by the Rhenohercynian zone with a “normal” West-European crust of 30 km thickness evident beneath the north-trending Hessische Senke. A single-ended profile again indicates a graben-like crustal structure west of the Leinegraben north of the Rhenohercynian zone. No details are available for the North German Plain where the central European rift system disappears beneath a sedimentary sequence of more than 10 km thickness. 相似文献
17.
Antonio Introcaso Myriam P. Martínez Mario E. Gimnez Francisco Ruiz 《Gondwana Research》2004,7(4):1117-1132
A gravimetric and magnetometric study was carried out in the north-eastern portion of the Cuyania terrane and adjacent Pampia terrane. Gravimetric models permitted to interpret the occurrence of dense materials at the suture zone between the latter terranes. Magnetometric models led to propose the existence of different susceptibilities on either side of the suture. The Curie temperature point depth, representing the lower boundary of the magnetised crust, was found to be located at 25 km, consistent with the lower limit of the brittle crust delineated by seismic data; this unusually thick portion of the crust is thought to release stress producing significant seismicity.
Moho depths determined from seismic studies near western Sierras Pampeanas are significantly greater than those obtained from gravimetric crustal models.
Considering mass and gravity changes originated by the flat-slab Nazca plate along Cuyania and western Pampia terranes, it is possible to reconcile Moho thickness obtained either by seismic or by gravity data. Thus, topography and crustal thickness are controlled not only by erosion and shortening but by upper mantle heterogeneities produced by: (a) the oceanic subducted Nazca plate with “normal slope” also including asthenospheric materials between both continental and oceanic lithospheres; (b) flat-slab subducted Nazca plate (as shown in this work) without significant asthenospheric materials between both lithospheres. These changes influence the relationship between topographic altitudes and crustal thickness in different ways, differing from the simple Airy system relationship and modifying the crustal scale shortening calculation. These changes are significantly enlarged in the study area. Future changes in Nazca Plate slope will produce changes in the isostatic balance. 相似文献
18.
南海西北部重磁场及深部构造特征 总被引：9，自引：3，他引：9
通过对南海重磁数据的重新处理,得到南海西北部自由空间重力异常图、布格重力异常图、磁异常图和化极磁异常图,并对所反映的地球物理场特征加以分析。根据重力场资料对研究区的地壳结构进行了反演计算,结果表明地壳厚度在10～38km之间,总的趋势由陆向洋逐渐减薄,对应于地壳类型从陆壳、过渡壳到洋壳的分布特征。根据磁力资料计算了居里面深度,其埋深变化于11～27km之间,在陆区居里面是下地壳顶界面和莫霍面之间的另一个物性界面,而在海区则接近于莫霍面埋深。 相似文献