sanded in
- Thread starter kirkn
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Mother Nature. 
king tides etc. hunt low tide if you can.
king tides etc. hunt low tide if you can.
Huge swells cause beach erosion, sometime when we get a big East Coast Low the swell can get up to 10 metres offshore and sends big waves onshore which rip the sand out to sea and deposit it elsewhere, leaves all the heavies on the eroded zone close to the surface.
There hasn't been a good one here for a few years and most of the beaches are sanded up. As soon as there is one it will be easy pickings.
There hasn't been a good one here for a few years and most of the beaches are sanded up. As soon as there is one it will be easy pickings.
You just have to keep a lookout but swell on an angle to the beach seems to work the best
Have you tried detecting the second beach?
Most beaches have a cycle they go through which rejuvenates the sand and shore of the main beach. This involves 2 beaches. The first one we all know and can easily see at the ocean edge, the second is just behind the dunes of the first. The dunes of the first beach typically have low vegetation on them that holds them together. Its just behind that you find the second beach.
Usually there is a low depression behind the dunes of the first beach and this fills with water to form a natural canal from the sea spray and high tides. Behind this water you find more dunes of the second beach leading up to the rock of the main coastline. These build up from the sand from the first beach being blown off the top of its dunes, forming the second beach. Sand from the second beach gets washed back onto the first beach as the water recedes with the tides. This cycle has been going on for thousands of years.
Because of mans need to build hi-rise developments by the sea side the natural order of things has been disturbed and most people are unaware that this second beach even existed at one point as now you only have one beach that has no hope of rejuvenating itself in the way it used to.
The Gold Coast in Queensland was a classic case of this. Before the hi-rise buildings were built if you looked at an aerial photo / map you would have seen the line of the two beaches and the natural canal. Notice the canal is full of sand that gets washed back onto the main beach by the tides:
They built the hi-rise buildings too close to the beach. They effectively built them right in front of the second beach and stopped the natural beach rejuvenation cycle. Now the second beach has been wiped out and all you are left with is the man made canals and the hard rock of the coastline inland from these where they should have built in the first place. Notice the canal is now devoid of sand, its been dredged out to make way for the boats and marina.
Now mother nature cant rejuvenate the beach and that is why they have to keep building large piers/groins out into the ocean and start dropping large boulders and concrete blocks on the shoreline to capture the sand and then have to bring in truck loads of sand after each big storm scours away the sand leaving only the coffee rock behind.
Now when the sand comes back because of all these man made mechanisms to trap it, it just builds up on the main beach and as you say you get "sanded in". There is nothing to hold onto this sand and it will be gone on the next big storm and just the coffee rock will remain.
The scientists have been arguing this case for years that they need to demolish the buildings over time and stop further development on the shoreline and only allow buildings back behind the canal.
If you ever get out into a remote part of Australia where man hasn't built big buildings up on the beach front you will see what I mean. This is getting harder to do as the bulk of the population of Australia live along the coastal regions.
You will find remnants of the second beach and this is where you should detect for old coins and the like because thats where the shoreline for the buildings used to be as you can see in the old photo.
Most beaches have a cycle they go through which rejuvenates the sand and shore of the main beach. This involves 2 beaches. The first one we all know and can easily see at the ocean edge, the second is just behind the dunes of the first. The dunes of the first beach typically have low vegetation on them that holds them together. Its just behind that you find the second beach.
Usually there is a low depression behind the dunes of the first beach and this fills with water to form a natural canal from the sea spray and high tides. Behind this water you find more dunes of the second beach leading up to the rock of the main coastline. These build up from the sand from the first beach being blown off the top of its dunes, forming the second beach. Sand from the second beach gets washed back onto the first beach as the water recedes with the tides. This cycle has been going on for thousands of years.
Because of mans need to build hi-rise developments by the sea side the natural order of things has been disturbed and most people are unaware that this second beach even existed at one point as now you only have one beach that has no hope of rejuvenating itself in the way it used to.
The Gold Coast in Queensland was a classic case of this. Before the hi-rise buildings were built if you looked at an aerial photo / map you would have seen the line of the two beaches and the natural canal. Notice the canal is full of sand that gets washed back onto the main beach by the tides:
They built the hi-rise buildings too close to the beach. They effectively built them right in front of the second beach and stopped the natural beach rejuvenation cycle. Now the second beach has been wiped out and all you are left with is the man made canals and the hard rock of the coastline inland from these where they should have built in the first place. Notice the canal is now devoid of sand, its been dredged out to make way for the boats and marina.
Now mother nature cant rejuvenate the beach and that is why they have to keep building large piers/groins out into the ocean and start dropping large boulders and concrete blocks on the shoreline to capture the sand and then have to bring in truck loads of sand after each big storm scours away the sand leaving only the coffee rock behind.
Now when the sand comes back because of all these man made mechanisms to trap it, it just builds up on the main beach and as you say you get "sanded in". There is nothing to hold onto this sand and it will be gone on the next big storm and just the coffee rock will remain.
The scientists have been arguing this case for years that they need to demolish the buildings over time and stop further development on the shoreline and only allow buildings back behind the canal.
If you ever get out into a remote part of Australia where man hasn't built big buildings up on the beach front you will see what I mean. This is getting harder to do as the bulk of the population of Australia live along the coastal regions.
You will find remnants of the second beach and this is where you should detect for old coins and the like because thats where the shoreline for the buildings used to be as you can see in the old photo.
