I was awakened by the recitation of the Koran in the morning, and since it was still early for breakfast, I went for a walk on the beach right next to the hotel. It was a full moon and the tide was low, creating vast mud flats. It is interesting that the beach is sandy, but the lagoon are mainly mud.

This is the first site we visited this morning, where Ordovician shales are transitioning to Silurian. There is a model of a graptolites at the entrance.

The old quarry, with the Ordovician in the foreground and the Silurian on the other side of the pool of water, is described on a board at the site. This is where we look for graptolites. Actually, the members of the group had been looking for it at the entrance, but I thought for sure it must be at the back, so we came to this place and found a beautiful and abundant graptolites. The 50 years of experience of Fossil Hunter is no joke!

I have found quite a few nice graptolite, not all over the place, but enough to look for. Compare this with a graptolite I collected from a Paleozoic layer in Oslo Bay, Norway, and sent to Japan a long time ago.
http://yossi-okamoto.net/.../Futen/2008_Norway/Oslo_5.html

This was the best sample of the day, and I asked everyone to take pictures. The density is much higher than the one in Oslo. As expected of a world GeoPark.

This is the round fossil that was discussed at the site. Someone said it might be the head of a graptolite, but I am skeptical.

The interesting geological feature is that the limestone mountain at the far end is completely Ordovician, while the one in the foreground is at the boundary between Ordovician and Silurian. Then, the stratigraphic plane tilting toward the pool on the right is oddly interpreted, isn't it? This is an interesting subject for discussion in high school and college geology.

The second outcrop of the morning is the one marked by the sign behind the banana fruit.

The sign says that it is a stromatolite of Ordovician age as well. The outcrop is explained by Dr. Hisada, a former Tsukuba University professor and the leader of this excursion, who also helped us with the 2017 Korat Plateau Dinosaur field trip.

http://seagull.stars.ne.jp/2017Thai_Khon_Kaen/Part1.html

This is the "stromatolite" in question. The reason I put it in parentheses is because there is some controversy. V san of Chula University who accompanied us expressed his opinion that it might be a dry fissure. The same opinion was expressed in the aforementioned discussion at the outcrop in Kanchanaburi, that it is a sedimentary structure or trace fossil, and it seems to be a source of controversy.

Here I did a little fossil hunting. I found a magnificent right-angled shell a little further up the rock. Dr. Hisada praised me for finding it. However, I got a taste of it, and when I went up to another rock, I was attacked by ants and bitten in several places on my body. Ouch, ouch!

This is the second outcrop of the "stromatolite". This is the place where the spirit, called "Pea" by the locals, is enshrined. It is preserved in a pavilion.

The weathering was less severe here, and the structure was easier to see. Fossil fragments were also found here.

I was a little tired after visiting two places, so I took a restroom break at a gas station. Cappuccino at Amazon, the equivalent of Starbucks here. If you order a regular cappuccino, it is too sweet, so the trick is to order a Less Sweet 25%.

After a late lunch at a restaurant, the afternoon's main activity is to climb up the old hill to the limestone caves in the middle of the cliff. This is also a national park and an entrance fee is required.

The steep hill is a well-maintained stairway, and after climbing it, we finally arrived at the entrance of the cave. It is said that 30 years ago, a Buddhist monk was looking for a place to meditate and found this cave by chance. The cave is now open as a tourist cave, but you have to be accompanied by a local guide to enter. The canoeing yesterday and the guiding on this day were both done by a system that employs local people, which is one of the purposes of Geo-Parks, according to the tour guide.

The ceiling inside the cave is really high, and the stalactites have not been discovered for a long time, so they have a pure white color and are not stained at all. I was overwhelmed by the scale and beauty of the cave, which I could not experience in any other limestone caves in Japan. It is indeed a world-class Geo-Park. Click to Video.

There is a large sink-hole on the way. Only here the sun shines and algae grows, turning the area green. The guide told us that there were fossils in this sink-hole.

We all searched frantically for fossils on the left wall. This one looks like an ammonite, but it might be a mollusk because it has no internal septa structure.

This is Nautiloid, you know, and we found a lot of them.

Back down the stairs to the entrance of the national park, there is also a sign for a Prayer Room. This is the world where Muslims live.

On the way back to the hotel, we passed through an area with strange rocks and monstrous stones, just like Guilin (although I have never been there). It was indeed a vast area of limestone that had been cut down.