{"title":"Identification and analysis of bottom simulating reflectors in the Foz do Amazonas Basin, Northern Brazil","authors":"L. Aguiar, A. Freire, C. Silva, W. Lupinacci","doi":"10.1590/2317-4889202120200075","DOIUrl":null,"url":null,"abstract":"This work proposed an additional approach to investigate gas hydrate occurrences in the Foz do Amazonas Basin, in the Brazilian Equatorial Margin. The automatic comparison of seafloor seismic amplitudes with those from the Bottom Simulating Reflectors (BSR) was used to exhibit the reversal of signal polarities among the seafloor (positive) and the BSR (negative), reinforcing the identification of BSR in areas where its visualization was unclear. Additionally, we used the envelope attribute to highlight the BSR in the seismic section. Subsequently, we decomposed the seismic data into different frequency bands, applied a -90 degrees phase rotation to the data and recalculated the envelope attribute for each section decomposed in frequency bands. This technique improved visualization, allowing the identification of intervals where BSR were laterally discontinuous, revealing to be valuable for mapping the gas hydrate distribution in Foz do Amazonas Basin.","PeriodicalId":9221,"journal":{"name":"Brazilian Journal of Geology","volume":"1 1","pages":""},"PeriodicalIF":1.3000,"publicationDate":"2021-01-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":"1","resultStr":null,"platform":"Semanticscholar","paperid":null,"PeriodicalName":"Brazilian Journal of Geology","FirstCategoryId":"89","ListUrlMain":"https://doi.org/10.1590/2317-4889202120200075","RegionNum":4,"RegionCategory":"地球科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":null,"EPubDate":"","PubModel":"","JCR":"Q3","JCRName":"GEOSCIENCES, MULTIDISCIPLINARY","Score":null,"Total":0}
引用次数: 1
Abstract
This work proposed an additional approach to investigate gas hydrate occurrences in the Foz do Amazonas Basin, in the Brazilian Equatorial Margin. The automatic comparison of seafloor seismic amplitudes with those from the Bottom Simulating Reflectors (BSR) was used to exhibit the reversal of signal polarities among the seafloor (positive) and the BSR (negative), reinforcing the identification of BSR in areas where its visualization was unclear. Additionally, we used the envelope attribute to highlight the BSR in the seismic section. Subsequently, we decomposed the seismic data into different frequency bands, applied a -90 degrees phase rotation to the data and recalculated the envelope attribute for each section decomposed in frequency bands. This technique improved visualization, allowing the identification of intervals where BSR were laterally discontinuous, revealing to be valuable for mapping the gas hydrate distribution in Foz do Amazonas Basin.
这项工作提出了一种额外的方法来调查巴西赤道边缘的Foz do Amazonas盆地的天然气水合物。使用海底地震振幅与底部模拟反射器(BSR)的自动比较来显示海底(正)和BSR(负)之间的信号极性反转,在BSR可视化不明确的地区加强了对其的识别。此外,我们使用包络属性来突出地震剖面中的BSR。随后,我们将地震数据分解为不同的频段,对数据进行-90度相位旋转,并重新计算各频段分解剖面的包络线属性。该技术提高了可视化效果,可以识别出BSR横向不连续的层段,这对于绘制Foz do Amazonas盆地的天然气水合物分布具有重要价值。
期刊介绍:
The Brazilian Journal of Geology (BJG) is a quarterly journal published by the Brazilian Geological Society with an electronic open access version that provides an in-ternacional medium for the publication of original scientific work of broad interest concerned with all aspects of the earth sciences in Brazil, South America, and Antarctica, in-cluding oceanic regions adjacent to these regions. The BJG publishes papers with a regional appeal and more than local significance in the fields of mineralogy, petrology, geochemistry, paleontology, sedimentology, stratigraphy, structural geology, tectonics, neotectonics, geophysics applied to geology, volcanology, metallogeny and mineral deposits, marine geology, glaciology, paleoclimatology, geochronology, biostratigraphy, engineering geology, hydrogeology, geological hazards and remote sensing, providing a niche for interdisciplinary work on regional geology and Earth history.
The BJG publishes articles (including review articles), rapid communications, articles with accelerated review processes, editorials, and discussions (brief, objective and concise comments on recent papers published in BJG with replies by authors).
Manuscripts must be written in English. Companion papers will not be accepted.