INDEPENDENT NEWS

Groundwater Drives Rapid Erosion Of The Canterbury Coastline

Published: Wed 13 Jan 2021 09:37 AM
Groundwater flow and seepage can form large gullies along coastal cliffs in the matter of days, it has been discovered, as per a recently-published paper.
An international team of scientists from Malta, Germany, Romania, New Zealand and USA has used drones and satellite imagery to monitor a stretch of coastline near Ashburton (South Island, New Zealand). They found that gullies up to 30m in length can develop in less than a week.
Field observations and numerical models have shown that groundwater plays a key role in forming these gullies, by either eroding tunnels or triggering landslides.
Gullies are an important coastal hazard. There is an average of one gully every 250m along the Canterbury coastline, and their formation leads to the loss of precious agricultural land.
Similar coastal gullies have been documented in South Taranaki (North Island, New Zealand), as well as other countries such as the USA, Japan and Brazil.
When and where coastal gullies form can be partly predicted. The study has shown that gullies form when more than 40mm of rain fall per day, and that they are preferentially located above buried, old river channels.
This study was led by Prof. Aaron Micallef from the Department of Geosciences, and is an outcome of the MARCAN project, which is funded by the European Research Council.

Next in Business, Science, and Tech

General Practices Begin Issuing Clause 14 Notices In Relation To The NZNO Primary Practice Pay Equity Claim
By: Genpro
Global Screen Industry Unites For Streaming Platform Regulation And Intellectual Property Protections
By: SPADA
View as: DESKTOP | MOBILE © Scoop Media