This study focuses on gas bubble emissions across ~ 1800 km2 of the southeastern continental slope of the Crimean Peninsula in the Eastern Black Sea basin. In total, about 3500 gas emissions were mapped as so-called flares in single- and multibeam echosounder imaginary. Flares generally emanate from the seafloor, with a few exceptions, where water depths are less than 700 m, which represents the upper limit of the gas hydrate stability zone in this region. Methane in shallow sediments below 700 m is transferred to methane hydrate, and the migration of free gas into the water column is therefore inhibited in most cases. This study illustrates further that flare occurrence is linked to morpho-structural margin characteristics. Two morphologically different margin segments are distinguished, and flare distributions were found to relate to differing morphological structures along these segments. In the western province, where the upper continental margin is steep and incised by gullies, flares occur mainly along downslope-oriented ridge crests. In the eastern province, representing a part of the Don-Kuban paleo-fan, the slope is influenced by extensive mass wasting. Gas emissions in this area were mainly detected aligned along scarps of submarine landslides and related to sediment failures. Almost all flares disappear in the acoustic records of the water column below a water depth of ~ 100 m suggesting that the gas bubbles dissolve within the water body of the Black Sea and contribute to its methane inventory and the anoxic water column.

中文翻译：

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黑海的甲烷气体排放——从克里米亚大陆边缘到刻赤半岛斜坡的映射

这项研究的重点是黑海东部克里米亚半岛东南大陆坡约 1800 平方公里的气泡排放。总共有大约 3500 种气体排放被绘制为假想的单波束和多波束回波测深仪中的所谓耀斑。火炬通常来自海底，但有少数例外，其水深小于 700 m，这代表了该地区天然气水合物稳定带的上限。700 m以下浅层沉积物中的甲烷转化为甲烷水合物，因此在大多数情况下游离气体向水体的运移受到抑制。这项研究进一步说明了耀斑的发生与形态结构边缘特征有关。区分两个形态不同的边缘段，并且发现耀斑分布与沿这些段的不同形态结构有关。在西部省份，上大陆边缘陡峭并被冲沟切割，耀斑主要发生在下坡导向的山脊顶部。在东部省份，代表顿库班古扇的一部分，斜坡受到广泛的大规模浪费的影响。该地区的气体排放主要是沿着海底滑坡的陡坡检测到的，并且与沉积物破坏有关。几乎所有耀斑在水深约 100 米以下的水柱的声学记录中都消失了，这表明气泡溶解在黑海的水体中，并有助于其甲烷库存和缺氧水柱。在上大陆边缘陡峭且被沟壑切割的地方，耀斑主要发生在面向下坡的山脊顶部。在东部省份，代表顿库班古扇的一部分，斜坡受到广泛的大规模浪费的影响。该地区的气体排放主要是沿着海底滑坡的陡坡检测到的，并且与沉积物破坏有关。几乎所有耀斑在水深约 100 米以下的水柱的声学记录中都消失了，这表明气泡溶解在黑海的水体中，并有助于其甲烷库存和缺氧水柱。在上大陆边缘陡峭且被沟壑切割的地方，耀斑主要发生在面向下坡的山脊顶部。在东部省份，代表顿库班古扇的一部分，斜坡受到广泛的大规模浪费的影响。该地区的气体排放主要是沿着海底滑坡的陡坡检测到的，并且与沉积物破坏有关。几乎所有耀斑在水深约 100 米以下的水柱的声学记录中都消失了，这表明气泡溶解在黑海的水体中，并有助于其甲烷库存和缺氧水柱。该地区的气体排放主要是沿着海底滑坡的陡坡检测到的，并且与沉积物破坏有关。几乎所有耀斑在水深约 100 米以下的水柱的声学记录中都消失了，这表明气泡溶解在黑海的水体中，并有助于其甲烷库存和缺氧水柱。该地区的气体排放主要是沿着海底滑坡的陡坡检测到的，并且与沉积物破坏有关。几乎所有耀斑在水深约 100 米以下的水柱的声学记录中都消失了，这表明气泡溶解在黑海的水体中，并有助于其甲烷库存和缺氧水柱。