Sediment core sampling using the vibracore
As a response to an increasing demand for deep sediment cores in support of marine licences for dredging operations, coastal development and cable/pipeline routing projects, Ecospan Environmental has invested in a small vibracorer. It is the ideal tool for taking sediment cores for contaminant or granulometric analyses in ports, harbours, estuarine and freshwater environments.
The vibracorer is a small compact unit that was purpose designed for the collection of aquatic sediment cores from relatively small vessels in waters of up to 30 m deep. It is usually deployed from our 7.9 m catamaran Coastal Surveyor, but can be deployed from significantly smaller vessels with an appropriate frame. For these reasons, the vibracorer can be deployed in freshwater, estuarine and inshore environments at a fraction of the cost of most other similar sampling methods.
The vibracorer can obtain sediment cores of up to 6 m long and 3 inches (76mm) in diameter from unconsolidated sediments. It works by vibrating the entire core tube at such a high frequency that the sediment becomes thixotropic causing the core tube to sink into the sediment. Further advancement will occur for the length of the core tube or until dry, compacted, or consolidated material is reached. In practice this means that the vibrocorer does not result in core compression and will take extremely high quality samples in mud and sandy sediments, but will not sample gravels to any depth. Recent projects