Hikaru Sawada

Hikaru Sawada
Japan Agency for Marine-Earth Science Technology | JAMSTEC

PhD

About

22
Publications
1,784
Reads
How we measure 'reads'
A 'read' is counted each time someone views a publication summary (such as the title, abstract, and list of authors), clicks on a figure, or views or downloads the full-text. Learn more
65
Citations

Publications

Publications (22)
Article
Full-text available
The Oeyama ophiolite unit is one of the oldest components of the subduction orogenic belts in the Japanese Islands and is important for understanding the initiation of plate subduction in the proto-Japan region. This study performed U–Pb and Lu–Hf isotopic and trace element analyses of zircon in gabbroic rocks from the Oeyama mafic–ultramafic compl...
Article
The Eastern Iratsu body of the Sanbagawa metamorphic terrane in central Shikoku recorded an Early Jurassic metamorphic event older than the Sanbagawa metamorphic event. This study carried out the petrochronology of eclogitic high-pressure marble in the Eastern Iratsu body to determine the corresponding conditions of metamorphism and their variation...
Article
Full-text available
The Hida granites, classified into the pre–Jurassic and Jurassic plutons in this study, are important components of the Hida belt, which is a Paleozoic–Mesozoic basement of the Japan arc and underwent Permian to Triassic metamorphism during the collision between the North and South China blocks. This study performed zircon U–Pb dating and whole–roc...
Article
The Shurugwi greenstone belt (SGB) in the central Zimbabwe Craton is one of the major volcano-sedimentary belts in the craton, but its formation age and tectonic history have not been well constrained. For revealing the evolution of SGB, this study performed in-situ U–Pb dating of zircons from meta-sedimentary rocks of the Wanderer and Mont d’Or fo...
Article
Full-text available
Datolite [CaBSiO4(OH)] was discovered in an eclogite–facies calcite marble collected from the Eastern Iratsu body in the Sanbagawa metamorphic belt of central Shikoku. The marble was composed of calcite, diopside, and garnet that contained inclusions of omphacite. Enclosed in the marble is a pod composed mainly of quartz, with subordinate calcite,...
Article
Full-text available
The size of continents is an essential parameter to understand the growth of the continental crust and the evolution of the solid Earth because it is subject to tectonism and mantle convection and affects the preservation of the crust. This article reviews the secular change in the size of continents on the early Earth, focusing on terrigenous clas...
Article
The Japanese Islands have evolved as a subduction-related orogenic belt since the Cambrian, as recorded by lower Paleozoic granitoids and blueschists. These older rocks occur as disrupted tectonic blocks within serpentinite mélange zones (e.g., the Kurosegawa belt in southwest Japan), which form a discontinuous belt less than a few kilometers wide....
Article
Although the Phanerozoic geology of the Central Asian Orogenic Belt is extensively studied, there is still much to reveal about the initiation and early stages of tectonism. The Gargan block of the Tuva-Mongolia terranes at the Mongolian-Russian border is one of the Archean-Proterozoic continental crustal fragments that record the earliest evolutio...
Article
Full-text available
The ca. 2.2‐2.1 Ga Magondi Supergroup on the Zimbabwe Craton in Southern Africa is mainly composed of sedimentary rocks deposited in a rift basin/passive continental margin, which record a unique episode in carbon isotope perturbation called the Lomagundi‐Jatuli Event (LJE). This study reports new U‐Pb ages of detrital zircons from the Deweras and...
Article
The Mikabu greenstones form accreted fragments of an ancient oceanic plateau, which are currently incorporated within the Cretaceous high P/T-type Sanbagawa metamorphic belt in SW Japan. Previous geological and petrological studies indicate that protoliths of the Mikabu greenstones were mafic/ultramafic volcano-plutonic rocks of oceanic plateau and...
Article
Full-text available
To understand the timing and mode of crustal production and reworking in the Archean, we performed U-Pb and Hf isotopic analyses of detrital zircon grains from the ca. 2.3 Ga Murmac Bay Group in the Rae Craton, central Canada. The zircon U-Pb ages range from 3.9 to 2.3 Ga with a significant gap interval of 3.6–3.3 Ga, indicating that felsic magmati...
Article
Zircon is the only candidate of Hadean terrestrial material that can be collected because it can survive physically and chemically, as well as maintain its U–Pb age system during omnigenous geological events. However, Hadean zircons are rare, so many age analyses of zircons are required to isolate Hadean zircon grains. There are two ways to improve...
Article
Full-text available
The extensive occurrence of a felsic continental crust is one of the unique features of the Earth. The growth history of the continental crust has been a key issue in understanding the origin and evolution of the Earth. In particular, recent geological studies indicate that subduction of the continental crust into the mantle has been greater than p...
Article
Full-text available
U-Pb ages of detrital zircons were newly dated for 4 Archean sandstones from the Pilbara craton in Australia, Wyoming craton in North America, and Kaapvaal craton in Africa. By using the present results with previously published data, we compiled the age spectra of detrital zircons for 2.9, 2.6, 2.3, 1.0, and 0.6 Ga sandstones and modern river sand...
Article
For the ca. 2.7 Ga (Neoarchean) clastic rocks in the Belingwe greenstone belt (Manjeri Formation), U-Pb age of detrital zircon grains were analyzed by Laser Ablation Inductively Coupled Plasma Mass Spectrometry (LA-ICP-MS). The Manjeri Formation, composed of sandstone, quartzite, and limestone with stromatolites, was deposited in a shallow marine s...