Processed Sub Bottom Profiler (SBP) data around Tristan da Cunha@en

Sub bottom profiler (SBP) aka sediment echosounder data. Sediment echosounder measurements were conducted continuously by means of Teledyne PARASOUND DS3 (P70) parametric sediment echosounder during both R/V MARIA S. MERIAN cruises, MSM20-2 (Jegen et al., 2015) and MSM24, until the shutdown of the system due to technical reasons on cruise MSM24. The system's beam width is 4.5° along-track and 5.0° across-track. The primary high frequency signal (PHF) with a frequency of about 18 kHz was recorded for water-column investigations while the secondary low frequency signal (SLF) with a frequency of 4 kHz is used to image the shallow sub-seafloor. This selection of four PARASOUND profiles were converted into SEG-Y data by using the PS32segy tool (Hanno Keil, University of Bremen, Germany). Afterwards, the ReflexW software57 (Sandmeier, 2012) was used to low-pass filter the data and to mute the water column.

本数据集为海底剖面仪（Sub Bottom Profiler, SBP），又称沉积物回声测深仪数据。本次研究采用特莱顿PARASOUND DS3（P70）参数式沉积物回声测深仪，在“玛丽亚·S·梅里安号”（R/V MARIA S. MERIAN）科考船的MSM20-2（Jegen等，2015）与MSM24两个航次中开展连续测量，直至MSM24航次因技术原因关停该系统。该系统的波束宽度为沿航迹向4.5°、跨航迹向5.0°。其中，频率约18 kHz的主高频信号（Primary High Frequency, PHF）用于水体剖面探测；频率为4 kHz的次低频信号（Secondary Low Frequency, SLF）则用于浅海底表层成像。本次选取的4条PARASOUND剖面数据，通过德国不来梅大学汉诺·凯尔（Hanno Keil）开发的PS32segy工具转换为SEG-Y格式数据。随后，使用ReflexW 57版软件（Sandmeier，2012）对数据进行低通滤波处理，并压制水体层信号。