Sea Technology

SEP 2017

The industry's recognized authority for design, engineering and application of equipment and services in the global ocean community

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36 st / September 2017 and a length of 35 cm. The base plate is a square-shaped steel plate, with a width of 25 cm and thickness of 1 cm. The ring-shaped lead weight stabilizes the sampling device and is set 20 cm above the steel base plate; the weight has an outer diameter of 30 cm, an in- ner diameter of 12 cm and a thickness of 5 cm. The sand samples are collected by dragging the device along the sea- floor to drag sand into the steel pipes, and a towel inside the steel pipes prevents the sand from fall- ing out as the device is pulled back up to the surface. The sampling device has a sim- ple structure and is easy to trans- port and operate. It is highly ef- fective in collecting sand samples from the seabed surface and can be used in a variety of water en- vironments. Testing To perform a proper test of the effectiveness of this new seabed sand sampling device, we per- formed dozens of experiments using the device in a Taiwanese shoal from July 15 to 21, 2016. The shoal was hydrologically complex, as the sand waves in the area had an average wave height of 13.5 m, with the water depth being 20.42 m at the peak of the sand waves, and the average wave height of the sand waves being two-thirds of the water depth. The wavelength of the sand waves mainly ranged between 500 to 700 m. The results of these tests are strongly representative of the performance of this sampling device. Each sample collec- tion was completed within 5 to 6 min. by one to two people, I n marine geology research, it is nec- essary to obtain a sufficient quantity of seabed surface samples, while also ensuring that the samples are in their original state. Currently, there are a number of seabed surface sampling devices available, but we find it is very difficult to obtain sand samples using these devices, particularly when deal- ing with fine sand. Machine-controlled seabed surface sampling devices are also avail- able, but generally unable to dive into deeper regions of water. To obtain larger quantities of seabed surface sand samples in their original states, many researchers have tried to improve upon sampling devices, but these efforts have generally produced ambiguous results, in our opinion. To resolve this issue, we have designed an im- proved and highly effective seabed surface sand sampling device that incorporates the strengths of a variety of sampling devices. It is capable of diving into deepwater to obtain fine sand sam- ples and is also suited for use in streams, rivers, lakes and seas with varying levels of depth (up to 100 m). This device can be used for geologi- cal mapping, underwater prospecting, geologi- cal engineering and ecological, environmental studies in both marine and terrestrial waters. Design The part of this device that collects the seabed sand samples is composed of three steel pipes, a steel supporting shaft and a ring-shaped lead weight, with each steel pipe being able to collect approximately 2 kg of sand samples in each sampling attempt. The length and diameter of the main supporting steel shaft are 50 cm and 8 cm, respectively. The three sampling steel pipes and the main supporting steel shaft are attached to the base plate, with each sampling pipe being separated by 120° from each other. The sampling pipes have a diameter of 8 cm Seabed Surface Sand Sampling Device Simple, Effective Tool for Geological Research By Dr. Xiaowen Luo • Dr. Ziyin Wu • Lingkun Deng (Top) A top-down diagram of the sam- pling device. (Bottom) A lateral dia- gram of the sampling device.

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