我校为板块构造在中太古代已启动提供构造地质学新依据
Our school has provided a new structural geology basis for operation of plate tectonics in the Mesoarchean
近日,中国地质大学(武汉)全球大地构造中心主任蒂姆·科斯基教授、地质过程与矿产资源国家重点实验室王璐教授指导我校苏丹籍博士留学生Abdelmottaleb Aldoud在国际著名地质学期刊《Geology》发表文章,题目为“皮尔巴拉克拉通中太古代穆尔甘丁纳(Mulgandinnah)剪切带是世界上最古老的弧形转换断层吗?”。这是我校留学生首次以第一作者在Nature Index期刊上发表国际SCI文章。
板块构造体制在地球的运行与地球宜居性的形成密切相关。地球早期的构造体制以水平运动为代表的板块构造为主,还是以垂向构造为代表的非板块构造体制为主,是地学研究的热点问题。现代板块构造体制在晚太古代地球运行的地质学记录已越来越多被发现,该体制能否继续往古-中太古代推进,尚未有明确答案。
Recently, Professor Tim Kusky, Director of the Center for Global Tectonics of China University of Geosciences (Wuhan), and Professor Wang Lu, State Key Laboratory, directed our Sudanese doctoral student Abdelmottaleb Aldoud to publish an article in the internationally famous geology journal Geology, entitled “Is the Mesoarchean Mulgandinnah shear zone, Pilbara Craton, the world’s oldest arc-slicing transform fault?". This is the first time that an international student from our school has published an international SCI article as the first author in the Nature Index journal.
The operation of plate tectonic system on Earth is closely related to the formation of its habitability. The early tectonic system of the Earth was mainly characterized by plate tectonics represented by horizontal movement, or non-plate tectonic systems represented by vertical tectonics, which is a hot topic in geological research. More and more geological records of the modern plate tectonic system during the late Archean Earth movement have been discovered, and there is no clear answer to whether this system can continue to advance towards the Paleo-Meso Archean.
众所周知,切穿岩石圈深度的弧形转换断层是汇聚边缘的重要构造地质学记录:它们发育在大洋板块的斜向俯冲体系,是大洋板块向海沟斜向俯冲过程中,垂直海沟走向的水平走滑分量形成的弧形走滑断层。该断层可切穿陆缘弧岩浆地质单元并使其整体发生横向位移,在随后的汇聚拼合造山过程中,上覆板块发育水平方向的构造单元重复出现和逆冲挤压推覆作用导致垂向上构造岩片的堆叠。现今在苏门答腊、新西兰和菲律宾处海沟正在发生大洋板块斜向俯冲的典型实例清楚地显示了这一现代地质过程,而古生代阿尔泰、新太古代苏必利尔克拉通和伊尔岗克拉通也有古代的实例。因此,弧形转换断层成为板块间发生水平构造运动的典型构造地质学记录。
As is well known, arc-slicing transform faults that cut through the depth of the lithosphere are important tectonic geological records of the convergence edge: they develop in the oblique subduction system above the oceanic plate, and are strike slip faults formed by the horizontal strike slip component parallel to the trench direction during the oblique subduction process of the oceanic plate towards the trench. This fault can cut through the magmatic geological units of the continental margin arc and cause overall lateral displacement. In the subsequent convergence and assembly process of mountain building, the horizontal structural units developed in the overlying plate are duplicated by the transform fault, moving once laterally continuous segments adjacent to each other. The typical modern examples of oceanic plate oblique subduction occurring above the trenches of Sumatra, New Zealand, and the Philippines clearly demonstrate this geological process, and there are also ancient examples of the Paleozoic Altai, Neoarchean Superior Craton, and Yilgarn Cratons. Therefore, arc-slicing transform faults have become a typical geological record of horizontal tectonic movements occurring between plates.
澳大利亚的皮尔巴拉(Pilbara)克拉通保存了古-中太古代岩浆活动和构造变形记录,是水平、垂向板块构造体制争议最多,也是解决这一争议的关键研究区,为探寻是否保留地球上最早板块构造地质历史记录提供重要研究场所。本研究表明,水平板块运动为特征的板块构造体制在太古代早期就已运作,证据为皮尔巴拉克拉通克拉通内保留的穆尔甘丁纳左行走滑剪切带杂岩体 (MSZC) (图 1),这可能是世界上已发现的最古老的弧形转换断层残留记录。这一研究为Pilbara克拉通存在水平运动板块构造体制提供关键证据。
The Pilbara Craton in Australia preserves records of Paleo- to Middle Archean magmatic activity and tectonic deformation, making it the most controversial horizontal and vertical plate tectonic system and a key research area for resolving this controversy. It provides an important research site for exploring whether to preserve the earliest plate tectonic geological records on Earth. This study indicates that the plate tectonic system characterized by horizontal plate movement has been in operation since the early Archean period, as evidenced by the Mulgandinnah sinistral strike slip shear zone complex (MSZC) preserved within the Pilbara craton (Fig 1), which may be the oldest remaining record of arc-slicing transform faults discovered in the world. This study provides key evidence for the existence of a horizontal plate tectonic system in the Pilbara Craton.
该文章记录了中太古代 MSZC 中记录的近30公里板块水平位移,并将其与显生宙斜向俯冲体系进行类比,表明 MSZC 是一个重要的板块构造边界断层。MSZC 切割并让一系列与弧相关的岩浆岩在该构造边界两侧重复出现 (图 2),表明它是一个弧形切割的走滑转换断层系统,类似于阿尔泰和现代板块构造体系中较年轻的地质记录实例。航磁数据集和地质图中标志性构造单元的运动学解析均展示了宏观尺度的脆性剪切作用,使至少29亿年前的弧相关地体发生位移,表明中太古代地球就已存在刚性板块岩石圈的水平运动地质记录。
This article records the horizontal displacement of at least 30 and perhaps several hundred kilometers of plates recorded in the Middle Archean MSZC and compares it with the Phanerozoic oblique subduction system, indicating that MSZC is an important plate tectonic boundary fault. MSZC cuts and causes a series of arc related magmatic rocks to repeat on both sides of the tectonic boundary (Fig 2), indicating that it is an arc-slicing strike slip type transform fault system, similar to younger geological record examples in Altai and modern plate tectonic systems. The kinematic analysis of landmark structural units in the aeromagnetic dataset and geological map both demonstrate macroscopic brittle shear effects, causing displacement of arc related terranes at least 3.0 billion years ago, indicating the existence of horizontal movement geological records of rigid plate lithosphere in the Middle Archean Earth.
该研究证明古-中太古代皮尔巴拉克拉通东部(最近被解释为岩浆弧中上地壳层的残留)被一条主要弧形切割断层切割和发生地质单元(3.0-2.93 Ga)的重复出现,该断层切割了中太古代弧系统先前 600 × 100 公里的区域,将不同部分的板块碎片横向移动到它们目前并置的 200 × 200 公里范围(图 3)。这一证据表明地球在~ 3.0 Ga 的中太古代,板块已发生大型横向水平运动,展示和保留了斜向俯冲、弧深成作用、弧切片和地质单元沿走滑断层两侧重复出现等地质记录,反映了现代板块构造样式的汇聚板块边界地壳生长模式在中太古代已大规模启动。
The paper revealed data that documents that the Paleo-Mesoarchean Eastern Pilbara craton, recently interpreted to be a preserved mid-upper crustal level of a magmatic arc, is cut and repeated by a major 3.0–2.93 Ga arc-slicing fault, the Mulgandinnah, which sliced a previously 600 × 100 km segment of a Mesoarchean arc system, laterally moving different segments to their presently juxtaposed 200 × 200 km preserved fragment (Fig 3). This evidence demonstrates lateral plate motions by 3.0 Ga, and shows oblique subduction, arc plutonism, arc-slicing, and repetition, reflecting that crustal growth in modern- style convergent margins was in full operation by the Mesoarchean.
据《地质学》官网主页显示,《地质学》是连续 16 年被 Web of Science 评为排名第一的“地质学”期刊,该期刊旨在发表具有国际研究意义的及时、创新且发人深省的代表性文章,期刊文章主题涵盖地球科学各个领域。
According to the homepage of the official website of Geology, Geology has been the Web of Science's #1 ranked "geology" journal for 16 years in a row. The journal Geology aims to publish timely, innovative, and provocative articles relevant to its international audience, representing research from all fields of the geosciences.
文章信息:Aldoud, A., Kusky T., and Wang L., 2024. Is the Mesoarchean Mulgandinnah shear zone, Pilbara Craton, the world’s oldest arc-slicing transform fault? Geology, v. XX, p. XXX–XXX, https://doi .org /10 .1130 /G52360 .1
![3BF062](/__local/4/40/8E/3C6C913FCDD0B53A215312A7D8C_95E6D931_3BF062.jpg)
图1:皮尔巴拉克拉通位置图
Fig 1: Location map of Pilbara Craton
![2A8F64](/__local/4/63/20/92EF68005DA6D3B038E504640DD_E7CF3756_2A8F64.jpg)
图2:(A)MZSC的Lalla Rookh段地图(B)标志性地质单元水平位移的详细信息。
Fig 2: (A) Map of the Lalla Rookh segment of the MZSC (B) Details of offsets of specific units.
![25DA0C](/__local/4/0B/86/C2ADC317CF87A63469151F07715_E9021A0F_25DA0C.jpg)
图3:皮尔巴拉克拉通的现今构造格局,是在古-中太古代板块斜向运动期间,通过对早前岩浆弧岩基和外侧的增生杂岩线性构造带进行弧型水平走滑切割而形成。粉红色虚线为深成岩体杂岩,基于年轻盖层下的地球物理解释结果。
FIG 3: Formation of the present-day preserved Pilbara craton by arc-slicing of a formerly linear magmatic arc batholith belt and outboard accretionary complex, during Paleo-Mesoarchean oblique plate motions. The pink plutonic complex with dashed lines is based on the geophysical interpretation of rocks under younger cover.