This EartCache brings you to a volcanics site located at Beraban, Kediri, Tabanan Regency, Bali.
EarthCache Description
The outcrop you see at the EarthCache site is Middle Pleistocene Buyan-Beratan & Batur Tuffs and Lahar Deposits (1.8 million to 126,000 years ago). It was formed from volcanic debris from Mount Buyan & Mount Beratan (both have become caldera lakes), and Mount Batur located in north of Bali. The tectonic instability of Bali was due to sinking of the oceanic crust of Indo-Australian Plate under the rigid Eurasian plate of Indonesian archipelago. This causes the region to experience frequent volcanic eruptions.
At the EarthCache site, you will study the characteristics of the volcanic rocks and beach material.
How to claim this EarthCache?
At the posted coordinates (there was a red flag when this EarthCache was created) look down and note what you see. Go to waypoint S1/STAGE1 Outcrop, look toward the cliff (northeast) and note what you see. Go to waypoint S2/STAGE2 Beach Material, look down and note what you see.
Send me the following;
1. The text "GC7CJHA Bali Volcanics I" on the first line.
2. The answers to the following questions;
- At the posted coordinates look down. You will see an outcrop of weathered tuff. Describe what you see.
i) Weathered looking outcrop with loose pieces of grey reddish irregularly shaped pebbles from 2mm to 30mm scattered on the ground and imbedded in finer matrix.
ii) Weathered looking outcrop with loose pieces of grey reddish rounded shaped pebbles from 2mm to 30mm scattered on the ground and imbedded in finer matrix.
iii) Weathered looking outcrop with loose pieces of grey black irregularly shaped pebbles from 2mm to 30mm scattered on the ground and imbedded in finer matrix.
iv) Weathered looking outcrop with loose pieces of grey black rounded shaped pebbles from 2mm to 30mm scattered on the ground and imbedded in finer matrix.
- At the waypoint Outcrop look towards the cliff (northeast). You will see layers of weathered tuff. Describe what you see.
i) Weathered looking layers with pieces of grey black irregularly shaped pebbles from 2mm to 30mm imbedded in finer matrix interbedded with layers of weathered looking grey fine material of <2mm.
ii) Weathered looking layers with pieces of grey black rounded shaped pebbles from 2mm to 30mm imbedded in finer matrix interbedded with layers of weathered looking grey fine material of <2mm.
iii) Weathered looking layers with pieces of grey reddish irregularly shaped pebbles from 2mm to 30mm imbedded in finer matrix interbedded with layers of weathered looking grey fine material of <2mm.
iv) Weathered looking layers with pieces of grey reddish rounded shaped pebbles from 2mm to 30mm imbedded in finer matrix interbedded with layers of weathered looking grey fine material of <2mm.
- At waypoint Beach Material look down. You will see the erosional products of the tuffs. Describe what you see.
i) The beach material is grey reddish and sandy (<2mm) with irregularly shaped pebbles (2mm to 10mm).
ii) The material beach is grey reddish and sandy (<2mm) with rounded shaped pebbles (2mm to 10mm).
iii) The beach material is grey black and sandy (<2mm) with irregularly shaped pebbles (2mm to 10mm).
iv) The beach material is grey black and sandy (<2mm) with rounded shaped pebbles (2mm to 10mm).
v) The beach material is grey reddish and sandy (<2mm).
vi) The beach material is grey black and sandy (<2mm).
3. Provide a photo of yourself or a personal item to prove you have visited the site.*
References
1 Moving Mountains: The Geology of Bali – http://baliadvertiser.biz/moving_mountains/ 2 Geologically Speaking – https://geologicallyspeaking.com/2015/07/17/the-new-decade-volcano-program-6-bali/ 3 Subduction zone beneath Java, Bali and Lombok islands, Indonesia http://www.earthobservatory.sg/resources/illustrations/subduction-zone-beneath-java-bali-and-lombok-islands-indonesia.
* Effective immediately from 10 June 2019, photo requirements are permitted on EarthCaches. This task is not optional, it is an addition to existing logging tasks! Logs that do not meet all requirements posed will no longer be accepted.
For additional information, visit; Geosociety.org, Geocaching.com Help Center and Geocaching.com Forum.
Finding the answers to an EarthCache can often be challenging, and many people tend to shy away from these caches because of this. However, it is my opinion that geocaching is also meant to be a fun family experience that simply aims to introduce interesting and unique locations such as this one. Flexibility on logging requirements, however, can only be applied if it can be established that you have actually taken the time to visit the site. For this reason, a proper log describing your adventure accompanied by a good number of photos would be much appreciated.