Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics
Heat Flow on the U.S. Beaufort Margin, Arctic Ocean: Implications for Ocean Warming, Methane Hydrate Stability, and Regional Tectonics
复制标题
北冰洋美国波弗特边缘的热流：对海洋变暖、甲烷水合物稳定性和区域构造的影响
DOI：
--
复制
发表时间：
2020
影响因子：
3.5
通讯作者：
B. Phrampus
中科院分区：
文献类型：
--
作者：
M. Hornbach;R. Harris;B. Phrampus
对美国博福特陆缘进行的第一次集中热流研究的结果提供了对十年尺度北冰洋温度变化的深入了解，并提出了有关博福特陆缘演变的新问题。本研究使用3.5 m Lister探针在103个地点测量热流，这些地点位于沿着四条南北向断面，垂直于约700 km长的美国博福特边缘。新的热流测量值，经季节性海洋温度波动和测深影响校正，显示在海平面以下300-900米的海底深度平均热流值较低（~35 mW/m2），而在接近预测的大陆-海洋过渡的海底深度> 1，000 mbsl的海底深度平均热流值非常高（~80 mW/m2）。在上缘测量的异常低热流值与先前的研究一致，表明十年尺度的海洋温度变暖到约500 mbsl。然而，我们的研究结果表明，这种海洋变暖可能会延伸到900 mbsl-400 m深的深度，比以前的研究更深，这意味着在美国博福特边缘的大部分地区广泛的，持续的甲烷水合物不稳定。在大陆-海洋过渡期海底深度> 1，000处观察到的异常高热流值的原因尚不清楚。我们提出了三个候选过程：（1）由于大洋-大陆过渡区最厚的沉积盖层，边缘边缘的产热较高，热导率较低，（2）向海迁移的地下平流，（3）阿拉斯加微板块北方边界可能的断层再活化。
Results from the first focused heat flow study on the U.S. Beaufort Margin provide insight into decadal‐scale Arctic Ocean temperature change and raise new questions regarding Beaufort Margin evolution. This study measured heat flow using a 3.5‐m Lister probe at 103 sites oriented along four north‐south transects perpendicular to the ~700‐km long U.S. Beaufort Margin. The new heat flow measurements, corrected both for seasonal ocean temperature fluctuations and bathymetric effects, reveal low average heat flow values (~35 mW/m2) at seafloor depths of 300–900 m below sea level (mbsl) and anomalously high (~80 mW/m2) values at seafloor depths of >1,000 mbsl, near the predicted continent‐ocean transition. Anomalously low heat flow values measured on the upper margin are consistent with previous studies suggesting decadal‐scale ocean temperature warming to ~500 mbsl. Our results, however, indicate this ocean warming likely extends to depths as great at 900 mbsl—400 m deeper than previous studies suggest—implying widespread, ongoing, methane hydrate destabilization across much of the U.S. Beaufort Margin. The cause of the anomalously high heat flow values observed at seafloor depths >1,000 at the continent‐ocean transition is unclear. We suggest three candidate processes: (1) higher heat production and lower thermal conductivity on the margin edge due to the thickest sedimentary cover at the ocean‐continent transition, (2) seaward migrating subsurface advection, and (3) possible fault‐reactivation at the northern boundary of the Alaskan Microplate.
影响因子：
3.7
作者：
M. Manga;M. Hornbach;A. Le Friant;O. Ishizuka;N. Stroncik;T. Adachi;M. Aljahdali;G. Boudon;C. Breitkreuz;A. Fraass;A. Fujinawa;R. Hatfield;M. Jutzeler;K. Kataoka;S. Lafuerza;F. Maeno;M. Martínez-Colón;M. McCanta;S. Morgan;M. Palmer;T. Saito;A. Slagle;A. Stinton;K. Subramanyam;Y. Tamura;P. Talling;B. Villemant;D. Wall-Palmer;Fei Wang
通讯作者：
M. Manga;M. Hornbach;A. Le Friant;O. Ishizuka;N. Stroncik;T. Adachi;M. Aljahdali;G. Boudon;C. Breitkreuz;A. Fraass;A. Fujinawa;R. Hatfield;M. Jutzeler;K. Kataoka;S. Lafuerza;F. Maeno;M. Martínez-Colón;M. McCanta;S. Morgan;M. Palmer;T. Saito;A. Slagle;A. Stinton;K. Subramanyam;Y. Tamura;P. Talling;B. Villemant;D. Wall-Palmer;Fei Wang
影响因子：
5.3
作者：
Neumann, Florian;Negrete-Aranda, Raquel;Gonzalez-Fernandez, Antonio
通讯作者：
Gonzalez-Fernandez, Antonio
影响因子：
5.2
作者：
Biastoch, A.;Treude, T.;Wallmann, K.
通讯作者：
Wallmann, K.