関連する実験動画
Updated: Jul 12, 2026

08:14
Atom Probe Tomography Analysis of Exsolved Mineral Phases
Published on: October 25, 2019
"ヘリウムスポット":上層マントルのダイアピルマグマによって引き起こされる
まとめ
科学者たちは,1966年のマツシロ地震の断層付近でヘリウムに富んだ土壌 ("ヘリウムスポット") を発見しました. これは,深層マグマの侵入がヘリウム異常と地震活動の両方を引き起こした可能性があることを示唆しています.
科学分野:
- 地質化学 地質化学
- 地震学 地震学とは
- 火山学 火山学とは
背景:
- 1966年のマツシロ地震群は,断層地帯に沿って発生した.
- 異常な土壌ガス組成は,地表下の地質学的プロセスを示す可能性があります.
研究 の 目的:
- マツシロ断層地帯に沿って発見された"ヘリウムスポット"の起源を調査するために.
- ヘリウム異常と1966年の地震群との関係を決定するために.
主な方法:
- 土壌ガスの採取と分析.
- ヘリウム同位体 (3He/4He比) の地化学分析.
- 地震データレビュー. 地震データレビュー.
主要な成果:
- 大量のヘリウム濃度 (350ppmまで) が断層に沿った土壌で検出されました.
- 高い3He/4He比 (8.90 +/- 0.31 x 10^-6) が測定され,マントルの源であることを示す.
- ヘリウムスポットの空間的分布は,断層地帯と相関していた.
結論:
- "ヘリウムスポット"と1966年のマツシロ地震は,マグマのダイアピラスの上昇と関連している可能性が高い.
- 直径約1kmのマグマ体は,両方の現象の源であると推論されています.
関連する概念動画
Noble Gases
The elements in group 18 are noble gases (helium, neon, argon, krypton, xenon, and radon). They earned the name “noble” because they were assumed to be nonreactive since they have filled valence shells. In 1962, Dr. Neil Bartlett at the University of British Columbia proved this assumption to be false.
Inductively Coupled Plasma-Mass Spectrometry (ICP-MS): Interferences
Inductively coupled plasma–mass spectrometry (ICP–MS) is a highly selective and sensitive technique for accurate elemental analysis. Though the analysis of ICP–MS mass spectra is comparatively straightforward, it is affected by spectroscopic and non-spectroscopic interferences. Spectroscopic interferences arise when the plasma contains ionic species with an m/z value the same as the analyte ion. Spectroscopic interference can be categorized as isobaric, polyatomic ions, and refractory oxide ion...
Hiatal Hernia
A hiatal hernia is the abnormal protrusion of the stomach or other abdominal organs through the esophageal hiatus of the diaphragm into the thoracic cavity.Normally, the gastroesophageal junction (GEJ) lies below the diaphragm and is supported by the phrenoesophageal membrane, the diaphragmatic crura, and connective tissues. Weakening of these structures—due to aging, congenital defects like a short esophagus, or increased intra-abdominal pressure from coughing, obesity, pregnancy, or heavy...
Inductively Coupled Plasma–Mass Spectrometry (ICP–MS): Overview
In inductively coupled plasma–mass spectrometry (ICP–MS), an inductively coupled plasma (ICP) torch is used as an atomizer and ionizer. Solid samples are dissolved and volatilized before being introduced into the high-temperature argon plasma, while solution samples are nebulized and passed through the high-temperature argon plasma. Plasma dissociates the analytes and ionizes their component atoms to form a mixture of positive ions and molecular species. The positive ions are then passed on to...
Emission Spectra
When solids, liquids, or condensed gases are heated sufficiently, they radiate some of the excess energy as light. Photons produced in this manner have a range of energies, and thereby produce a continuous spectrum in which an unbroken series of wavelengths is present.
Imperfections in Crystal Structure: Non-Stoichiometric Defects
Non-stoichiometric defects refer to a type of defect in the crystal structure of a compound where the ratio of its constituent elements deviates from the ideal stoichiometric ratio. There are two main types of non-stoichiometric defects: metal excess defects and metal deficiency defects.Metal excess defects occur when there is a slight surplus of metal ions than what is required by the stoichiometric ratio of the compound. For example, heating a sodium chloride crystal in sodium vapor results...

