期刊
ESTUARINE COASTAL AND SHELF SCIENCE
卷 172, 期 -, 页码 93-107出版社
ACADEMIC PRESS LTD- ELSEVIER SCIENCE LTD
DOI: 10.1016/j.ecss.2016.02.005
关键词
South America; South Africa; Acoustic survey; Shallow gas; Coastal evolution
资金
- CNPq [300437/2009-9, 471518/2010-7, 141975/2011-3]
- CAPES [BEX0267-13-9, CIMAR23038.004306/2014-17]
- CECO-UFRGS
- PGI [24/H099, 24/H107]
- PIP [5538, 00699]
- PID [25/B028]
- Water Research Commission [K5/2336]
- National Research Foundation of South Africa [87654]
- Marine Geosolutions Pty Ltd
- National Ports Authority of South Africa
Acoustic anomalies in seismic records have revealed that gas-charged sediments are very common features in the coastal environments around the world. The ubiquitous gassy sediments challenge the effective acoustic mapping of shallow stratigraphy by seismic means, as well as having an important influence on environmental issues related to the coastal zone occupation and management. This paper documents examples of gassy sediments from coastal lagoons, estuaries, rivers, bays and the inner shelf and nearshore environments of Brazil, Argentina and South Africa. Seismic echograms from selected areas show several gas-related anomalies, which present distinctive morphologies for sediment-trapped gas, leaking or free gas discharge into the water column. In several places the gas-charged sediments occur in areas of palaeo-topographic lows related to fluvial channels and valleys that developed in the coastal zone due to sea level oscillations during the Quaternary period. This forcing by palaeo-topographic features results in the occurrence of shallow gas being controlled in most coastal sites by the previous environmental scenario, the stratigraphic arrangement of the transgressive infilling elements, and the local hydrodynamic conditions. (C) 2016 Elsevier Ltd. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据