過去の表面環境の範囲を広げること:スヴァルバルドのネオプロテロゾイク期の氷河湖
Huiming Bao1, Ian J Fairchild, Peter M Wynn
1Department of Geology and Geophysics, E235 Howe-Russell Complex, Louisiana State University, Baton Rouge, LA 70803, USA. bao@lsu.edu
Science (New York, N.Y.)
|January 3, 2009
まとめ
スヴァルバルドの三重酸素同位体データによると,ネオプロテロゾーイク硫酸は異常な大気条件を示唆している. この発見は,非常に高い二酸化炭素レベルか,またはこの古代氷河期間に馴染みのない酸素循環を示しています.
科学分野:
- 地質化学 地質化学
- 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
- 同位体地質学とは,同位体地質学である.
背景:
- 地球上の硫酸塩の酸素同位体組成は,地球表面のプロセスに敏感です.
- ネオプロテロゾイク期の"スノーボール"氷河は,地球の生物圏と大気圏に大きな影響を及ぼした.
- 過去の大気条件を理解することは,気候モデリングに不可欠です.
研究 の 目的:
- ネオプロテロゾーイク期の氷河ダイアミクチットから硫酸の酸素同位体組成を分析する.
- ネオプロテロゾーイク時代の潜在的な大気条件を調査する.
- 極端な氷河期が地化学サイクルに与える影響を評価する.
主な方法:
- ネオプロテロゾーイク期の氷河ダイアミクチート群の内にある炭酸レンズから硫酸塩を抽出する.
- 三重酸素同位体組成物の分析.
- 酸素同位体組成の既知の自然の範囲と比較.
主要な成果:
- 硫酸三重酸素同位体値は,現在知られている自然の範囲の外にあります.
- データは,ネオプロテロゾーイク氷河期における異常な大気条件を示唆している.
- この発見は,非常に高い大気中の二酸化炭素か,または馴染みのない酸素循環のいずれかを示している.
結論:
- ネオプロテロゾイク期の大気は,氷河期における独特の特徴を示した.
- 観測された同位体データは,古代の酸素サイクルに関する現在の理解に挑戦しています.
- ネオプロテロゾイク期の大気組成とその影響を完全に解明するには,さらなる研究が必要である.
さらに関連する動画
13:38Laser-Induced Fluorescence Emission (L.I.F.E.) as Novel Non-Invasive Tool for In-Situ Measurements of Biomarkers in Cryospheric Habitats
Published on: October 26, 2019
14:38Establishment of Microbial Eukaryotic Enrichment Cultures from a Chemically Stratified Antarctic Lake and Assessment of Carbon Fixation Potential
Published on: April 20, 2012
関連する概念動画
01:50Global Climate Change
Throughout its ~4.5 billion year history, the Earth has experienced periods of warming and cooling. However, the current drastic increase in global temperatures is well outside of the Earth’s cyclic norms, and evidence for human-caused global climate change is compelling. Paleoclimatology, the study of ancient climate conditions, provides ample evidence for human-caused global climate change by comparing recent conditions with those in the past.
01:24Freshwater Microbial Ecology
Freshwater systems such as streams, rivers, and lakes exhibit distinct physical and biological characteristics that influence their microbial communities. These environments are broadly categorized into lotic systems—those with flowing waters like streams and most rivers—and lentic systems, which include still or slow-moving waters such as lakes, ponds, and marshes.In lentic systems, phytoplankton drive primary production, generating autochthonous organic carbon. In contrast, lotic systems...
01:21Green Algae
Green algae, also referred to as chlorophytes, are different from red algae in having the chloroplasts containing chlorophylls a and b, which give them their distinct green hue. However, they lack phycobiliproteins, preventing them from developing the red or blue-green pigmentation seen in red algae. In terms of photosynthetic pigment composition, green algae closely resemble plants and share a close evolutionary relationship with them. Taxonomically Green algae belong to Phylum Chlorophyta in...
01:21Isothermal Processes
A thermodynamic process that occurs at constant temperature is called an isothermal process. Heat slowly flows into the system or out of the system to maintain thermal equilibrium. Processes involving phase changes like water evaporation into steam or freezing water into ice at a constant temperature are examples of Isothermal Processes.
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
An ideal gas can also undergo isothermal expansion or compression.
For example, consider 1 mole of an ideal gas inside an isolated cylinder at initial volume V...
01:23Surface Appendages of Archaea
Archaeal surface appendages are highly specialized structures essential for environmental adaptation, encompassing roles in adhesion, biofilm formation, and motility. Among these appendages, pili and archaella stand out for their distinct morphologies and functionalities, enabling archaea to thrive in diverse and often extreme environments.Pili: Adhesion and Biofilm FormationPili are filamentous structures assembled from pilin protein subunits, primarily contributing to adhesion and biofilm...
01:18Deep Sea Microbial Ecology
The deep ocean and its underlying sediments represent vast, largely unexplored microbial habitats that extend far beyond the sunlit photic zone. The photic (euphotic) zone typically spans the upper ~100–200 meters of pelagic waters in the open ocean, but its depth varies geographically and seasonally, where sufficient light supports photosynthetic life. Below this lies the deep sea, spanning roughly 1000–6000 meters (bathypelagic to abyssal zones), with deeper hadal trenches extending beyond...