Excursion on the Web---Engineering geology in Japan
In this page, geological or geographical phenomena, or notable civil constructions from the viewpoint of engineering geology reported in the recent issues of the Journal of the Japan Society of Engineering Geology are presented with their photographs.
Crick photographs to enlarge and to get short explanations.

INDEX


Vol.  No.1 No.2   No.3  No.4 No.5  No.6. 
 42             
          Big projects in Kyushu , Japan
 43             
 Fossil Ripple Marks at Shishikui-ura  An excavated base for a Dam  Aso-4A Volcanic pyroclastic flow  The fomation of fracture or small fault in geological layer  Outcrops of Izumi group in a quarry site  Kayo Formation in Okinawa
 44             
 Yarlung Tsangpo  Upper regulating reservoir of the Okumino hydro power plant    Tsunami stones in Okinawa  Near Infrared Color Image showing the a dcreas of algae after dam dicharging  
 45             
   Kushiro coal mine  Kakinohanahijya  Chi-Chi earthquake , present condition  A scenic photo along Tan-Lu fault zone  Water-bearing stratum in Kumamoto region
 46             
 Rock avalanche,
Monk Blanc
 Cappadocia,National treasure of Turkey  Terano landslide  Chelungpu Fault at Chunshan,Taiwan  Moejima and Sakurajima island  Kidoyama-seihou fault of Ohara fault system
 47             
 Cuernos del Paine  Limestone open cut mining  Imbricated structure of the front of landslide      Controlled disposal site
for the Hakkouda Tunnel project
 48             
 Showcase to preserve an active fault      Mt. Damavand, the highest peak of Iran, large travertine deposit and limestone sinkholes in Lar valley  Carbonate chimneys at Dragon valley at Bamiyan,Afghanistan  Toppling failure occurred on a cut slope in Shimanto Belt


Vol.42 No.6
From big projects in relation to engineering geology through the 20th Century located in Kyushu , Japan.
The only one lift bridge in Japan constructed on poor subsoil on the Saga Line of ex-Japan National Railroad. It is used as a sightseeing facility now. (on the boundary of Saga Prefecture and Fukuoka Prefecture, Japan ;left upper).
Artificial island for ventilation of the Miike Coal Mine. ( Fukuoka Prefecture, Japan ; right upper)
The Wakato Ohashi Bridge over the Dokai Bay. (Fukuoka Prefecture, Japan ; left middle )
Outer bank of reclamation work for prevention of disaster in the Isahaya Bay. ( Nagasaki Prefecture , Japan ; right middle)
Geothermal power plant located at Kuju Highland. ( Oita Prefecture, Japan ; left lower)
Impervious work at an underground dam in Miyakojima Island. ( Okinawa Prefecture , Japan ; right lower )
( Photographed by Yushiro IWAO. )

Vol.43 No.1
“Fossil Ripple Marks at Shishikui-ura” crops out on a face of slope of a coastal road in Shishikui Town, Tokushima Prefecture, Japan. They are fossil current ripples on a bedding plane in sandstone-rich alternating beds of sandstone and mudstone of the Naharigawa Formation , deposited during Eocene within the Shimanto Belt. They are Natural Monument of Japan and are said as the largest and the most beautiful fossil ripple marks in Japan.
(Photographed by Wakio SUIDO)

Vol.43 No.2
Figure shows that an excavated base for the Mikawasawa Dam exposes Mesozoic sandstone and shale with porphyrite intrusion, which belong to the Ashio Accretionary Complex located in the northern Kanto district in Japan. The dam is a concrete gravity dam by the RCD method for multi-purpose use. Its dimensions are 48.5 m in height, 97.5 m in length and 28,367 m3 in volume. In the central part of the photo an almost vertical dyke of the pale colored porphyrite intrudes into the sedimentary rocks. Some right-lateral displacements of the dyke are caused by faults running parallel with the bedding planes. The sandstone beds consist mostly of lens and blocks of sandstone, and show a large variation in the strike direction. This sandstone-shale complex is interpreted as olistostrome. The interval between white lattice lines is 5 m. Red lines indicate outline of the dam.
(Photographed by Seiji NAKAO)

Vol.43 No.3
Photograph is the outcrop with 50m high of Welded tuff (Aso-4A Volcanic pyroclastic flow). This large outcrop is situated at Deai bridge located around Krio ,Ogata-tyo, Ono-gun, Oita prefecture ,Kyusyu district, where large columnar joints with 1 to 2 m in breadth are developed. Columnar joints extended regularly from top and bottom, and entablature of middle portion are observed clearly. A few meters rocks separated from joints plane and collapsed.

Vol.43 No.4
The formation of fracture or small fault in geological layer depends on the particle size of the clastic grain. While the conjugate fault and parallel small faults develop methodically in the sandstone layer on this outcrop, a lot of irregular small cracks and fractures with few centimeters width develop in conglomerate.
These photographs are taken at Shirahama of Kamiko Motojima in Izu peninsula. Widths of all photographs in right column are approximately 1m.
(Photograph by Mr. Kazuo Kosaka)

Vol.43 No.5
Outcrops of Izumi group in a quarry site located in Seto town, Naruto city, Tokushima prefecture, Japan.
Izumi group is considered as a marine-origined stratum in the late Cretaceous (Champagne period). These outcrops here belonging in Izumi group, which sedimentary rocks in alternating beds of sandstone and mudstone with 40〜60% sandstone share, is classified " sandy mudstone facies". Many sandstone beds with several 10cm〜1m thickness are found in these outcrops, and characteristic sedimentary structures such as graded bedding and slump structure are observesd in these sandstone beds.
(Photographed by Tsunehiro YOSHIDA)

Vol.43 No.6
The photograph is showing an outcrop of the Kayo Formation (alternating beds of sandstone and shale, or those of sandstone and slate) characterized by folds. On the successive sea cliff of the Pacific coast from Teniya to Banzaki in the City of Nago situated in the northern part of the main island of Okinawa, Japan, pre-Tertiary turbidite strata of the Kayo Formation (correlative to the Shimanto belt) crop out and exhibit conspicuous folds. Most of these folds are in the form of anticline, the axial plane of which is facing southeastward (dipping northwestward). These folds presumably form a part of decollement resulted from thesubduction of the Kula-Pacific Plate. (Photographed by Tetsuo AMAYA)

Vol.44 No.1
Yarlung Tsangpo, originated from the north face (ca. 80゜E, 30゜N) of the central Himalaya Mountains, traces through the Tibet, from the west to the east. Around the border between the Union of Myanmar and the Kingdom of Bhutan, it changes the direction to south-west, be called as the Brahmaputra Rivers, then merges with the Gangis River, and turns into the Bay of Bengal.
This river reaches about 3000 km. A cyclone in this region always causes this river to flood the land of the People’s Republic of Bangladesh. This picture was taken at the point 500km east from the Lhasa, on the way to the then-unregistered Namchabarwa (7782 km). Sediments are composed of the debris of gneiss from upstream, included a lot of muscovite and mica. Reflected sunlight makes a fantastic view.
(Photographed by Shuusuke Kitahara)

Vol.44 No.2
Kaore dam (107.5m in height) was constructed by Chubu Electric Power Company (Japan) as the upper regulating reservoir of the Okumino hydro power plant. It is a typical arch-gravity type dam recently built in Japan. It is in the V-shaped valley at the uppermost part of the Nishigabora-dani River of the Kiso-gawa river system, located in the Village of Itadori, Gifu prefecture, Japan. The geology of the dam site is Cretaceous Omodani rhyolites, and small-scale intrusions of porphyrite are found in some parts of the dam site. The upper picture is provided by courtesy of Hazama Corporation (Japan). The lower two pictures are provided by Isao SHIOZAKI : the left one was taken on October 19, 1993, in the early stage of the test impoundment ponding of the reservoir, and the right one shows the ponding condition on October 3, 1995.

Vol.44 No.3

Vol.44 No.4
The limestone blocks on the Miyara Bay shore on the Ishigaki Island in Okinawa Prefecture (left). The right end block in the upper left photograph has 3 meter height, and about 5 meter diameter. Kato and Kimura (1983) showed that these blocks are the tsunami stones drifted up by the Yaeyama Earthquake Tsunami in 1771 from the result of dating of Favia speciosa on the blocks.
(Photographed by Toshihumi Yoneshiro).
The limestone block called Okosukobizi(Obi-Ohiwa) on the coral reef terrace of Simoji Island in Okinawa Prefecture (right). According to the ancient writing, the block is also supposed to be derived from the Yaeyama earthquake Tsunami,and to be named Obi-Ohiwa for the notch ,which is compared to being belted (Obi means a belt in Japanese),carved in its middle part. It is considered as the biggest existing tsunami stone in the world.
(Photographed by Tetsuo Amaya)

Vol.44 No.5
Near Infrared Color Images taken from a low altitude of 50 m using Kite Balloon ;
The images were taken before and after discharging from Miharu Dam (Fukushima Prefecture in Japan). The Near Infrared Color Image corresponds to the false color image of satellite images, and the reddish color increases in Near Infrared Color Image as rich in algae on the river bed, whereas the reddish color decreases as poor in algae. These images show reddish color decreasing with poor algae after the dam discharge.
(upper : before dam discharge, lower : after dam discharge; courtesy of OYO Corporation)

Vol.44 No.6

Vol.45 No.1

Vol.45 No.2
Kushiro coal mine is a famous submarine coal mine in the eastern part of Hokkaido district in Japan. Figure shows that an excavated new longwall mining face in 2002, which is 330 meters in depth under the sea floor and minus 350 meters in elevation, exposes an old adit with wooden supports excavated between 1955 and 1965 that is filled by deformed coal rich layers such as folding. The layers under the invert at the adit have upheaved to the roof of the adit. Other old adits often fill their spaces with ground water. A plan of study tunnel in the mine will be considered to clarify the mechanism of their strange phenomena.
(Photographed by Yoshihisa ICHIHARA)

Vol.45 No.3
Kakinohana river (Kakinohanahijya), located at Tamaki village south of Okinawa island. This natural spring selected one of the Japanese 100 fine natural water in 1985 by the Environment Agency, is situated about 300m down along stone pavement path south of village. This spring water gush out from Ryukyu Limestone which deposited in Pleistocene age, have supported the life of people in village. Family and others visit this place for relaxation and good landscape mainly in summer season.

Vol.45 No.4
A large and devastating earthquake, Chi-chi earthquake, occurred in central Taiwan on September 21st. This earthquake caused by the slide of the Chelongpu fault. The new waterfall with 5-meter vertical offset was formed in the Tachia River. The left under photograph show the site just after the earthquake and the upper one show present situation. Chinshui Shale at Pleiocene, partially including sandstone and mudstone, was weathered on that area. Collapsed Pifeng bridge over the fault has been rebuilt in the way that remained part and new part of bridge have been connected. But the bridge is not straight horizontally due to the fault displacement.
(Photograph by Dr. Weiren Lin)

Vol.45 No.5
A scenic photo along Tan-Lu fault zone in the east of Heifei city, Anhui prefecture, China.
Tan-Lu (Tancheng-Lujiang) fault is a major fault, which extends more than 2,400km from the north bank of downstream area of Chang Jiang river to the northwest China through Shandong peninsula with direction of north-northeast.
The location of this photo is a southern part of Tan-Lu fault, about 130km west-southwest from Nanjing city. Landslide scars are found sporadically in this region. Their occurrence coincides with outcrops of fracture zone of limestone (right in the photo, near view) and granite (middle in the photo, distant view). On the other hand, smoke rises up from the back side of rock-fill dam (left in the photo). This smoke results from rich clay mining in this fault fracture zone. The power lines (upper in the photo) run from here to coal thermal power plants in Heifei city.
(Photographed by Kazuo KOSAKA)

Vol.45 No.6
The cover of this issue was photographed during the field trip of the 2004 Fall Convention of the Japanese Association of Groundwater Hydrology held in Kumamoto November 2004. Groundwater in the Kumamoto region is recharged in the Kikuchi Plateau lying next to the foot of the Aso Caldera and the middle Shirakawa River Basin. The water-bearing stratum in the region consists of the deposit of Aso pyroclastic flow and Togawa lava. Togawa lava (lower left photo) is especially porous and cranny, and forms a major groundwater flow path to Lake Ezuko (upper photo) where 400,000 tons of water springs daily. The waterworks department of the local government takes the water from the stratum. The lower right photo shows a swimming pool utilizing the abundant supply of water in the area.
(Photographed by Isao SHIOZAKI)

Vol.46 No.1
A rock avalanche on the surface of the glacier at the foot of Mont Blanc. Mont Blanc is the highest mountain in western Europe. Its height is about 4,810 meters. This photograph was taken from a point near the entrance on the Italian side of the Mont Blanc Tunnel in the 12th overseas excursion to the Alps sponsored by JSEG on August 25, 2004. Brenva Glacier characterized by rugged clustered seracs, is situated between Black-Aiguille (2,922m) on the left hand side of the Mont Blanc glittering in a silver color and an arete of Brenva Aiguille on the right. This glacier is once interrupted by a steep slope of the glacial steps down below where massive jointed rocks crop out with a bumpy surface texture. A large amount of gray debris is distributed on the basal part of this slope without a landform characterized by glacial deposits. Crevasses on the surface of the debris indicate the presence of the concealed glacier flowing as a black glacier. This place is a terminal part of the trace of the rock avalanche on January 18, 1997, caused by a large-scale rock collapse occurred in the upstream area of the glacier.
(Photographed by Shuichi HASHIMOTO)

Vol.46 No.2
The District of Cappadocia located at the central portion of the Anatolia Peninsula, Republic of Turkey, is registered as the National Treasure because of its view of the unique erosion topography, and historic and cultural values of the ancient-city sites.The strange rocks with bamboo shape, are the column-shape remains resulted from the erosion of volcanic sediments. Some rocks have basaltic rocks on the top like hats. Now, we can enjoy this unique view on the air balloon ride. The Catholic had lived in this area form A.D. 4 C. They built the underground cities by boring the basement of tuff,in order to escape from persecution of the Rome Empire. At its peak, they built the underground cities including monastery, schools, depository of foods, graves, other than houses. Around 20,000 people are believed to live there. (Photographed by Hiroshi Oshima)

Vol.46 No.3
Terano landslide caused by 2004 Niigata-Chyuetsu earthquake.
The earthquake occurred around 5: 56 pm October 23, 2005. Within an hour after the main quake, many aftershocks followed, including two upper 6 quakes on the Japanese earthquake scale. These quakes caused more than 1,000 slope disasters in and around the former Yamakoshi-mura area. The cover photo of this issue, which was taken one week after the occurrence of the initial tremor, depicts a landslide damming back the Imo River. The geometry of the trees under the main scarp of the landslide, the sub-scarps in the moving blocks, severed asphalt roads, the alignment of tree stands, etc. shown in the picture suggest the pattern of the mass movement. It also shows the rise of the water level of the Imo River due to the damming effect. (Photograph by Tsuyoshi Haraguchi)

Vol.46 No.4
The north wall of the trench dug on the Chelungpu Fault at Chunshan, Taiwan.
In the left below map1), red broken line shows the trace of Chelungpu Fault which is the surface rupture occurred at the Chi-Chi Earthquake 1999, and solid circle shows the location of the trench.
The center below sketch2) shows the geological structure of the trench wall, and there are several faults which occurred at various age.
The vertical displacement of this point at the Chi-Chi earthquake is about 2m, and the horizontal displacement is about 3.5m.
These displacement are not only cased by faulting, but also mainly by folding in the hanging wall side.
(Photographed by LIN, Weiren and  YEH, En-Chao)
1) Ma et al. (2003) : Evidence for fault lubrication during the 1999 Chi-Chi, Taiwan earthquake (Mw 7.6), GRL, vol.30, 1244, doi : 10. 1029.;
2) http://ashan.gl.ntu.edu.tw/chinese/earthquake

Vol.46 No.5
Aerial photograph of the Sakurajima Island and Shinjima (Moejima) Island.
The Moejima Island was formed through the upheaval of the see floor caused by the magma intrusion that resulted in the Annei eruption(1779〜1780) of the Sakurajima Volcano. The Moejima shirasu is dominantly distributed on the island and the Moejima shell bed overlies it. Plenty of Neopycnodonte musashiana, which lives in deep water of a depth of about 100 meters, is contained in the Moejima shell bed. The beach erosion for 200 years after its formation has been so remarkable that the island’s area has been significantly
reduced and the island is now under the preservation by wave dissipating concrete blocks and revetments.Several volcanic active faults with a throw of over 20meters in east -west trend can be seen in the island.
(photograph by Tuyoshi Haraguchi 2004/12/30)

Vol.46 No.6
Outcrop of an active fault which is the east end part of Kidoyama-seihou fault of Ohara fault system.
A beautiful active fault had appeared in a cut slope in the construction works of proposed prefecture road Sakoda-Shinome line in Shinomenakago Area, Ato town, Yamaguchi prefecture. Fault gouge, which is ten centimeter thick, white to greyish white color and originated from the bed rock, clearly continues in a gravel layer. One meter height of fractured bed rock at the toe of the slope can be seen in the north side of the fault with fault gouge. This bed rock covered with firm gravel layer is rhyolitic tuff belongs to Shinome formation Abu group. In the south side of the fault, the bed rock can not be seen, and well grained and loose gravel layer contacts with the fault.
(Photographed by Takuya MORIOKA)
Vol.47 No.1

There are aiguilles named “Cuernos del Paine” which abraded by glacier in center part of Paine National Park located in Patagonia in place in which it entered from the south end Strait of Magallanes to inland a little in South America.
The white colored middle part of the aiguilles is composed of granitic batholith.
The black colored upper and lower part of the aiguilles are composed of hornfels have undergone thermal metamorphism of sedimentary rocks in the Mesozoic.

Vol.47 No.2

Limestone open-cut mining of Sumitomo Kogyo located at Matsudate district, HachinoheCity, Aomori prefecture. It is called Hachinohe Canyon alias. The height between ground surface and deepest part (-135m under sea level) is approximately 240m, and maximum diameter at north-south direction and east-west direction are about 1800m and 800m respectively. Big size bivalve fossil of Megadoron in 200 Ma was occurred in this area.

Vol.47 No.3

Imbricate structure formed within the compression ridge of the front of landslide movement mass.This imbricate structure of the compression ridge was confirmed in the drainage trench excavated at the front of landslide movement mass at Nakashibetsu-chyo, Hokkaido.The movement mass are composed of mainly tephra from Mashu volcano in the latter Pleistocene to Holocene.Left side of this photo will be head side of movement mass and right side will be front side.4 thrust faults are observed at center of this photo, it is assumed that each thrust block were piled in order from front side (right side of photo), by the observation result of displacement of each faults.
Moreover, it is assumed that this structure was continuously formed by one time activity of landslide, because of comparatively well reserved beds before deformation.

Vol.47 No.4
 Vol.47 No.5  
 
 
Vol.47 No.6   
 Because the Hakkouda Tunnel on the route of Tohoku Shinkansen was excavated near an old mining area, there was concern about the environmental impact to the surrounding area made by the acid water due to the decomposition of sulfide minerals such as pyrite and by the elution of heavy metal that were contained in the rock muck derived from the excavation work. In the Hakkouda Tunnel project, therefore the rock muck which could cause such water pollution was disposed into a controlled disposal site.
These photographs show the controlled disposal site under construction and after its completion. The upper left photograph shows the situation of the installing impermeable liner on the bottom base of disposal site, and upper right photograph shows the temporary capping executed before snowfall period. The middle left and lower left photographs show the fairing of the disposal and the execution of the permanent capping respectively. The photograph at the lower right shows the final shape of the whole disposal site including the controlled disposal site.
(Photographed by Takehiro OHTA ,Yoshihiro TERASHIMA)
 
Vol.48 No.1

The photograph shows a showcase to preserve an active fault exposed on a cut slope.
This showcase is to preserve a part of an outcrop of the active fault appeared during the prefectural road improvement work at Shinomenakagou, Ato-town,Yamaguchi prefecture.It was installed in December 2005 by the procurer of the work, Yamaguchi prefecture Ato civil engineering office.The showcase preserves the fault in the area of 3m×3m.The showcase is designed to have three tempered glass doors that can move from side to side.The white gouge can clearly be observed to show the bedrock and sediment layer are in fault contact.The photograph of the fault taken before the cut slope was covered by protection layer is shown on the front cover of Journal of JSEG,vol.46,No.6(Feb.2006).
(Photographed by Tatsuya MORIOKA)

 
 Vol.48 No.2  
 
 
 Vol.48 No.3  
 
Vol.48 No.4

Mt. Damavand (EL. 5,610 m), the highest peak of Iran in the Alborz Mountain Range as much as 3000 meters high, is an impressive stratovolcano during the Quaternary (Picture at the top of the page). Lar Dam, a fill type dam, was constructed in foot of Mt Damavand in 1981 for the purpose of water supply for Teheran, the capital of Iran. However, water level of the reservoir is still below the intake facility because of remarkable water seepage from the dam reservoir. Andesitic lava of Damavand volcano covers the left bank of the dam site. The Jurassic to Cretaceous limestone is distributed from the reservoir area to the downstream of the dam site. Linearly-aligned old and new limestone sinkholes, maximum hole 20 m- 30 m in diameter, are found along the coast of the dam reservoir (Picture on the bottom-left corner). A large travertine deposit crops out in the Lar valley at the downstream of the dam site (Picture on the bottom-right corner). These limestone sinkholes might be created by erosion due to hot water infiltration through faults, and possibly cause the said water seepage from the dam reservoir.

(Photographed by Shuichi Hasegawa)
Vol.48 No.5

The picture at the top of the page presents an unusual landscape of carbonate chimneys at Dragon valley approximately seven kilometers to the west of Buddhist monuments at Bamiyan. The carbonate chimney grows upward in the direction opposite to stalactite, and forms a semi-logarithmic-curved surface shape. A river course behind the chimneys in this picture was changed its direction by continuous blowout of carbonate minerals from these chimneys. This is one of the few cases in land-forming process except for erosion. The picture at the bottom of the page is an anaglyph-image of the carbonate chimneys, which provides a stereoscopic effect of views, when viewed with two different color (red and cyan) glasses. Thanks to advancement in computer image processing technique, color photo-editing tool for a stereo effect image has been developed in addition to monochrome streoscpic imaging familiar to us.

(Photographed by Kaoru Shima)

Vol.48 No.6

This photograph shows a toppling failure occurred on a cut slope with the alternation of strata of mudstone-dominant sand-and-mud-stone in the Shimanto Belt. The deformation of the cut slope occurred when the cut at a ridge-like convex part reached to the planned plane. The cut slope is 44 meters high, with a gradient of 1:10, and 130 meters long. Regarding its geometrical relation to the geologic structure, it lays parallel to the strike, inclining 75 to 85 degrees to the strata of a system of fissures dipping backward. The sandstone formation consists of a geologic stratum with 10 centimeters thick, showing a discontinuous lenticular form, and the bedding planes partially interlace one centimeter or less thick clay layers. Many drops facing toward the mountain are found in the study area, and they are approximately one meter high at maximum, occurring at the layered crushing.

 (Photographed by Masashi UENO)