This is a view of the mountains to the east from a highway parking area bypassing the city of Kanchanaburi. Later I found out that most of the towering cliffs are made of Paleozoic limestone or dolomite (CaMgCO3). I have never been to the Grand Canyon in the western United States, but I have heard that the soaring cliffs are also made of limestone.

Aside from the exterior of the building, the interior exhibits were magnificent. There are many displays of geological overviews and fossils of the area. Unfortunately, most of the exhibits were in Thai, and the explanations to the seven high school students who went with us were also in Thai.

This is the Nautiloid of Ordovician age, which makes this area famous. The English description is also helpful. You can see the rounded reticular pattern on this stone. I will show you a photograph of an actual outcrop later, but he explained that it is stromatolite. However, there were objections to this opinion, which I will explain in the below column on the second day.

This is another famous Ordovician fossil called Tentaculite. It is one of the major Ordovician index fossils, although it is almost unknown in Japan. It is quite small in size in this area, but I remember seeing the same type (but from the Silurian, more younger era) in Oslo, Norway, in 2008, which was larger than this. Here is a photo of the locality of the supposed fossil of the same species in Oslo: http://yossi-okamoto.net/.../7-8_Aug_Paleo/p1140635.jpg A tour of the Oslo paleosols can be seen at: http://yossi-okamoto.net/.../Futen/2008_Norway/Oslo_3.html

Now, here is another explanation of the museum's prized specimens. Unfortunately, it was in Thai.

This is a crinoid that floats in the sea, and I seem to remember that this is the first discovery of this kind in Southeast Asia. This fossil is not the stem part of the famous sextant, but the round part that formed the float.

A simple model of a Nauiloid is used for explanation. Here, I explained to the students the difference between cephalopods such as ammonites and snails. In short, the difference is whether the inside of the shell is hollow for floating and sinking, or whether it is filled with body. The students listened attentively. This time, all the students were boys.

Now, a short drive from the museum, there is an outcrop where you can find fossils of Nauitiloids. The outcrop is a vast open area dotted with rocks left by weathering of limestone. Can you see the reticulated pattern near the feet of the person on the left?

This is it. The museum staff said this is a kind of stromatolite. My first impression was that it was a very different stromatolite from what I knew. As I mentioned above, I will deal with this again in my report on the second day. The age is Ordovician limestone.

In some places, there are a few layers as shown here. The stratigraphic plane can be seen from here, but it seems to be slightly tilted from the horizontal. There are some explanatory signs.

Here is a typical longitudinal section of a Nautiloid. You can see the air-entraining septum structure, similar to that of ammonites.

In other places, you can see what seems to be a bedding structure. The stratum is gently dipping to the right. I forgot to check the direction at the site.

This is a rather nice longitudinal section of a Nautiloid fossil, showing the air chamber and the septum. Surrounded by the "stromatolite" limestone. However, the internal structure unique to stromatolites is not clearly visible.

The lower part of a series of limestone layers shows a pronounced lamina. This is a place that my friend Dr. B would be pleased to see.

Occasionally, we can see such upper sandpipe-like structures and turbidite-like structures as shown in the next picture. Dr. S, a researcher of paleontology focusing on radiolarians at the Department of Geology, Mahidol University, who will be introduced in the below, Part 2, said that there should be traces of water flow in the slightly deeper part of the deposit (the lower part of the land shelf).

This is an interesting structure, and clearly the upper layer is cutting into the lower layer. The bottom part of the upper layer (gray area) contains fine fossil fragments, so I imagine that it is a turbulent mudflow (limestone composit) deposit.

This is also a very delicate deposit. I don't remember which is the upper side.

The reticulation appears again at the bottom.

The morning excursion ended with lunch with the students at a restaurant near the famous 7 waterfalls. I was accompanied by my caretakers, Dr. L sensei., the head of the SciUS organization in the Faculty of Science at Silpkorn University, Dr. A sensei, a professor in the Department of Natural Geography, and three SciUS staff members. A male teacher also came to take care of the boy students.

The students are taking out their swimsuits from their luggage to swim in the waterfall. Dr. L. sensei is laughing and commenting below (in my FB).

Prepare our swimming trunks and climb up the trail of this series of seven waterfalls. All of them are quite beautiful. As I found out later, they are all formed by the erosion of limestone. I thought it was similar to the dish pattern in limestone caves.

We came down from the mountain after climbing to the seventh waterfall and swam in the basin of this third waterfall. All the teachers were reserved, but I was not afraid, so I swam with boys. Of course, I showed them how to do the butterfly with my life jacket on. I had dinner the next day with Dr. S, who retired from the University of Tsukuba and is now teaching at Mahidol University here. He said that we Japanese had not better to swim in the flesh water in Thailand. The reason is that it is dangerous to swim in freshwater because of the presence of unknown bacteria. Also, he said that it is OK as long as the temperature is above 50 degrees Celsius, like in a hot spring. Seawater is not a problem. ---I have not had any physical problems in the past few days.

One of the seven students had a smartphone, so I asked him to take a picture of the seventh and final waterfall. The surface of the waterfall is covered with a white calcareous cover, like stalactites in a limestone cave. After this, two young men of Western descent actually tried to climb up the cliff on the left side of this waterfall, but the warden found them and whistled them down. Thailand is a country that is quite concerned about environmental conservation. The following photos will be shown in the next section.

Now the last outcrop of the day was on the left side of the entrance from the national road; into the tourist waterfall. The literature says it is a Cambrian sandstone (quartzite).

Unlike the limestone around the waterfall, this sandstone layer is quite solid. I showed the students how to use a hammer to get a better view of the sandstone, after a permission by the gatekeeper.

The sandstone seems to have become quartzite due to some pressure and heat. There is a little lamina-like residue.

This is Dr. L., sensei, a chemistry specialist who always takes care of us. She told me that she is not good at geology, but she seemed to be very interested in the field.

Another close-up photo. The lamina is visible. The lamina appears to be a parallel lamina. This concludes the inspection report for the first day. We will continue with the second day. Stay tuned.

The main campus of Mahidol University is in Bangkok, but I learned for the first time that there is another campus in the mountains of Kanchanaburi. I also heard that the university was built here because the Department of Geology insisted on using it as its headquarters. However, there are now several environmental and other departments in addition to the Department of Geology. Most of the campus is covered with forest in the countryside, which is no exaggeration. This is an orchid blooming in front of the dormitory on the campus.

The flowers resemble those of Cattleya, but are probably of the Denfale type. The showy color and large petals suggest that it is probably a garden variety.

I was surprised at how magnificent the dormitory was, which I could not believe it was on the university's premises. Of course, the air conditioner is new and works well.

I was surprised to see a shower room like this, which was the image of a luxury hotel. It had been a while since I had a hot shower.

We left our luggage in the room and moved to a restaurant along the Kwai River side for dinner. It is located on the edge of a small town with a train station about 10 minutes away by car. The sunset was beautiful. It was like a stage for a painting. The view of the rugged mountains formed by karst is also nice. Note. Kwai River is the Japanese name for the river. For more information, please visit: https://web-gis.jp/GS.../GeoDocument/GeoSite_W05-043.html

The next day, after breakfast, I went to examine the limestone rocks on the grounds of the lodge, which I had been eyeing. It was not easy to find fossils. I found out later that the limestone was not from the Permian but from the Triassic period, and that there are few fossils because it is dolomite. It looked like a nice limestone and I had high hopes for it.

Dr. P, a student of Dr. S sensei (see below), brought a map and explained the topography at the view point. He explained that the jagged mountains seen in the distance are made of limestone and have jagged edges.

The tour of the day was a visit to the Geology Museum of the Faculty of Geology, Mahidol University. The museum is located in the magnificent building of the Faculty of Geology.

Dr. P in the back and Dr. E on the left took turns explaining the rocks on display. It was very interesting for me, but I am not sure how it would have been for students with less knowledge of geology.

At lunch time, Dr. Looknum of Silpakorn University, who organized this field trip, handed out thank-you cards to the three people who helped us. The one who is handing now is Prof. Sashida. He is going to retire at the end of this September, and I think it was a good timing to ask him to visit us. Incidentally, during lunch, Dr. E san and Dr. P san informed me that an international conference on geology will be held at this campus in January next year. I had already signed up for a geological field trip to southern Thailand organized by another Japanese academic society at the end of December, and I had a great plan to attend the conference so that I could repair the seismograph that I had presented to Silpakorn University before the conference. I am also happy to be able to visit Thailand again.

After lunch, we visited the rock garden in the campus. Here, too, the two speakers continue their passionate speeches. They spoke mainly in English, sometimes in Thai, so that we could understand them. The man in the back wearing a mask in the foreground is Prof. S sensei. It was impressive to see him calmly listening to the explanation of his students. We promised to meet again in January, after his retirement, at a conference to be held here.

At the point of a huge cut rock containing fusulina and coral, Prof. S sensei, who had been quietly listening to their explanation, explained to the students in English himself. I noticed that I went to the car to get a bottle of water, came back and splashed water on the surface to make it easier to see the fossils, and Prof. S sensei praised me. It is difficult to see in the picture, but the dense Fusulina is beautiful.

This is a dense corals on the top of the same rock. The appearance was cleaned up by watering it.  I made the scale at home and gave it to each student as a gift to advise them to always put something on the scale when they take a picture.

There are more than 40 numbered plaques and rocks in the petrographic garden, which would take more than half a day to visit. I visited only the most important parts of the garden, which took up the entire morning.

The last place to visit near the end of the rock garden is the display of rocks (sandstone) from the formation that contains the well-known dinosaur bones and footprints from the Korat Plateau. These rocks were given to the department by the DMR (Geological Survey of Thailand), a cooperative project of the famous Thai geologist who established the department, almost for free. They were given to him almost for free.

After having lunch at the university cafeteria, I thanked Prof. Sashida sensei and Dr. Earth who were going back to their work, and Dr. P san took us to the abandoned elementary school. We parked the car on the ground and walked along the side of the school building. On the left is a field with a cassava plantation all over.

We were taken to a place with weathered soil characteristic of the red tropics, which I was told was the field of Dr. P's research. This red sandstone (which doesn't look like it because of the weathering) and the limestone layer a little to the right produce Permian fossils, I was told.

This is the limestone layer. There is a fossil-like pattern.

When enlarged, the cross section looks like a bivalve shell, but this is not a bivalve shell, but a Brachinopod (brachiopod) with an asymmetrical cross section. I taught the students how to use a hammer here and let them use mine and Dr. P's hammers to break the stone. We brought some valuable fossils back to the school.

I thought that was the end of it, but we found one more place around the elementary school building. This was the site of Dr. P's undergraduate thesis. Here, too, we find a magnificent fossil of Fusilina, and Dr. P san is drawing a diagram to explain the internal structure of Fusilina to our students.

The last destination of the day was the "Kwai River Bridge", which is an important place for Japanese to remember the history of Kanchanaburi during the WWII. I remember going to see the movie "Bridge over the River Kwai" when I was in elementary school. My homeroom teacher at that school was a music teacher, and we formed a student orchestra to perform the theme song "March on the River Kwai" at a concert. I really appreciate all the help I received from Dr. Looknum Sensei of the screen during my stay, including thid field trips.

We walked across the Kwai River Bridge. The width of the river is quite wide and we crossed to the other side, but there are not many stores on the other side, so we walked back home again. This side of the river seems to be more crowded as a tourist spot.

After returning to the bridge and back, the teachers were waiting for something. I wondered what they were waiting for, but it turned out to be the time for the train to come. It was a precious experience for me. The video shows a train slowly crossing the bridge. The video starts with two tourists from southern Europe who were taking pictures in front of me, and they stepped onto the tracks, so the train stopped and the driver got angry with them. So, other than swimming in the waterfall and the last train ride, it was a great trip for me, but I don't know if the students and teachers were impressed or not. This concludes my Kanchanaburi Diary.