関連する実験動画
Updated: Jul 15, 2026

06:04
Simulation of the Planetary Interior Differentiation Processes in the Laboratory
Published on: November 15, 2013
バイカル湖の長い堆積物核の年齢
Alexander A Prokopenko1, Eugene B Karabanov, Douglas F Williams
1Department of Geological Sciences, University of South Carolina, Columbia, South Carolina 29208, USA. sasha@geol.sc.edu
Nature
|March 5, 2002
まとめ
バイカル掘削プロジェクト (BDP-98) のコアには,アジアの珍しい古気候記録があります. 私たちの石器学的な分析は,その年齢モデルから100メートルのセクションを除外することは不当なものであることを示唆しています.
科学分野:
- 古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは,古代気候学 (paleoclimatology) とは
- 堆積地質学 堆積地質学とは
- アジアの気候史 アジアの気候史
背景:
- バイカル掘削プロジェクト (BDP-98) のコアは,重要な,長い,そして継続的なアジア大陸の古気候アーカイブを表しています.
- このような高解像度の堆積物記録は,世界中で希少であり,BDP-98は過去の気候の動態を再構築するために不可欠です.
研究 の 目的:
- BDP-98コアの年齢モデルから100メートルの間隔を除外することを再評価する.
- Kashiwaya et al.による信号処理と年齢モデルの構築の妥当性を評価するために. リトロジック分析を用いて.
主な方法:
- BDP-98のドリルコアセクションの詳細なリトロジック検査.
- 既存の年齢モデルに対する堆積物学的データの比較分析.
主要な成果:
- 石器学的な研究は,Kashiwaya et al.によって切断された100メートルの間隔を示しています. 誤ったデータの特徴を示さない.
- 年代モデルからこの重要なセクションを除外することは,堆積物学的証拠に基づいて不当なものとみなされます.
結論:
- BDP-98の古気候記録の整合性は,かなりの間隔の不当な切除によって損なわれることがあります.
- 正確な古気候再構築のために,BDP-98年齢モデルのさらなる調査と潜在的な修正が必要である.
関連する概念動画
Atomic Mass
Atoms — and the protons, neutrons, and electrons that compose them — are extremely small. For example, a carbon atom weighs less than 2 × 10−23 g. When describing the properties of tiny objects such as atoms, we use appropriately small units of measure, such as the atomic mass unit (amu). The amu was originally defined based on hydrogen, the lightest element, then later in terms of oxygen. Since 1961, it has been defined with regard to the most abundant isotope of carbon, atoms of which are...
Nuclear Stability
Protons and neutrons, collectively called nucleons, are packed together tightly in a nucleus. With a radius of about 10−15 meters, a nucleus is quite small compared to the radius of the entire atom, which is about 10−10 meters. Nuclei are extremely dense compared to bulk matter, averaging 1.8 × 1014 grams per cubic centimeter. If the earth’s density were equal to the average nuclear density, the earth’s radius would be only about 200 meters.
To hold positively charged protons together in the...
To hold positively charged protons together in the...
Radioactive Decay and Radiometric Dating
Radioactivity is a spontaneous disintegration of an unstable nuclide and is a random process, as all the nuclei in the sample do not decay simultaneously. The number of disintegrations per unit time is called the activity (A), which is directly proportional to the number of nuclei in the sample. The decay constant (λ) is an average probability of decay per nucleus in unit time.
Atomic Nuclei: Nuclear Magnetic Moment
All atomic nuclei are positively charged. When they have a nonzero spin, they behave like rotating charges. As a consequence of their charge and spin, these nuclei generate a magnetic field (B). This, in turn, gives rise to a magnetic moment (μ), which is randomly oriented in the absence of an external magnetic field. When an external magnetic field (B0) is applied, the magnetic moment vectors can align with the field or against it in 2 + 1 orientations. A hydrogen nucleus, which is just a...
Atomic Nuclei: Larmor Precession Frequency
The earth's gravitational field produces a 'twisting force' perpendicular to the angular momentum of a spinning mass (such as a spinning top) that causes the mass to 'wobble' around the gravitational field axis in a phenomenon called precession. Similarly, the magnetic moment (μ) of a spinning nucleus precesses due to an external magnetic field directed along the z-axis. The precession of the magnetic moment vector about the magnetic field is called Larmor precession, and the angular frequency...
Atomic Weight
Protons and neutrons have approximately the same mass, about 1.67 × 10-24 grams. Scientists arbitrarily define this amount of mass as one atomic mass unit (amu) or one Dalton. Electrons are much smaller in mass than protons, weighing only 9.11 × 10-28 grams, or about 1/1800 of an atomic mass unit. As a result, they do not contribute much to an element's overall atomic mass. This means that, when considering atomic mass, it is customary to ignore the mass of any electrons and calculate the...

