A new method to assess long-term sea-bottom vertical displacement in shallow water using a bottom pressure sensor: Application to Campi Flegrei, Southern Italy
A new method to assess long-term sea-bottom vertical displacement in shallow water using a bottom pressure sensor: Application to Campi Flegrei, Southern Italy
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DOI：
10.1002/2016jb013459
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发表时间：
2016-11-01
影响因子：
3.9
通讯作者：
Beranzoli, Laura
中科院分区：
文献类型：
--
作者：
Chierici, Francesco;Iannaccone, Giovanni;Beranzoli, Laura
我们提出了一种新的方法，使用底部压力记录仪（BPR）测量结合海平面，水柱和气压数据，以评估长期的垂直海底变形，在浅水环境中的几厘米的精度。该方法有助于消除由BPR仪器漂移和海水密度变化引起的数十厘米量级的视垂直位移。我们已经将该方法应用于2011年在Campi Flegrei Caldera海洋部门96米深度部署的BPR采集的数据，在几厘米幅度的海底隆起事件期间，持续了几个月。该方法探测到破火山口垂直隆起2.5 +/- 1.3厘米，在测量浅水海底垂直变形方面达到了前所未有的精确水平。在BPR的估计垂直变形也比较有利的陆基GPS站位于相同的距离，从最大的建模变形场所获得的数据。虽然BPR测量通常是在深海沃茨，海洋噪声相对较低，并在快速，大幅垂直地面位移的地区，所提出的方法扩展的能力，估计垂直隆起从BPR时间序列到浅水沃茨和缓慢的变形过程。
We present a new methodology using bottom pressure recorder (BPR) measurements in conjunction with sea level, water column, and barometric data to assess the long-term vertical seafloor deformation to a few centimeters accuracy in shallow water environments. The method helps to remove the apparent vertical displacement on the order of tens of centimeters caused by the BPR instrumental drift and by seawater density variations. We have applied the method to the data acquired in 2011 by a BPR deployed at 96m depth in the marine sector of the Campi Flegrei Caldera, during a seafloor uplift episode of a few centimeters amplitude, lasted for several months. The method detected a vertical uplift of the caldera of 2.5 +/- 1.3 cm achieving an unprecedented level of precision in the measurement of the submarine vertical deformation in shallow water. The estimated vertical deformation at the BPR also compares favorably with data acquired by a land-based GPS station located at the same distance from the maximum of the modeled deformation field. While BPR measurements are commonly performed in deep waters, where the oceanic noise is relatively low, and in areas with rapid, large-amplitude vertical ground displacement, the proposed method extends the capability of estimating vertical uplifts from BPR time series to shallow waters and to slow deformation processes.