Granite Point, Tanjung Krasak, South Bangka Island

Tanjung Krasak or Krasak Point, situated at southern part of Bangka Island. The point composed of jointed granitic rocks. The granite is Triassic and associated with tin mineralization.



Figure 1 (above) and 2 (below). Tanjung Krasak or Krasak Point. Taken in August 2006.

Regards,
Wahyu

Geureutee Rockycoast, Aceh Westcoast

Geureutee Mountain is part of Sumatra Bukit Barisan which extending from Lampung to Aceh. The mountain is composed of reef limestone (sorry, I do not know age of the limestone). The photo shows a rockycoast where the mountain meet the Indian Ocean at westcoast of Aceh.



Photo 1. Geureutee Rockycoast, Aceh Westcoast. The white stripe at the foot of the mountain is the imprint of the 26 December 2004 tsunami. Taken in August 2006.

Regards,
Wahyu

Beach, Cliff, and Reef Flat at Tanjung Bira

Tanjung Bira situated at eastern part of southern coast of South Sulawesi. The area is composed of reef limestone. There are tourist resort at the point. Figure 1 show situation of the coastal area.


Figure 1. Beach, Cliff and Reef flat at Tanjung Bira. Taken in September 2002.


Regards,

Wahyu

Java Southern Coast, Pacitan, Watukarung

Kabupaten Pacitan (Pacitan District) is part of Central Java Province, and situated in the middle of southern part of Java island. Physiographically, Pacitan coastal zone is part of Southern Mountain (Pegunungan Seribu) region that composed of reef limestones. The coastal zone face to Indian Ocean and has rugged character plan shape. There are many alternation of headlands and bays or pocket beaches as shown in Photo 1.

Photo 1. The coast of Watukarung, Pacitan, Central Java that show stack and headland of reef limestones, and sandy beach of carbonate sand. The coast has coastal platform, and high of berm surface from mean sea level is about 2 meters. There are notch at the lower part of the stack and headland. Photo: from Author, Januari 2006.

Regards,

Wahyu

How often Tsunami in Indonesia?

Last updated: 19 July 2006.

In periods of 1990-2006, 10 tsunami have occured in Indonesia. The map (Figure 1) shows the distribution of the tsunamis.

Figure 1. Tsunamis distribution in Indonesia in periode of 1990-2006.

1. Alor, Nusa Tenggara, 1991; 2. Flores, Nusa Tenggara, 1992;

3. Banyuwangi, East Java, 1994; 4. Biak, Papua, 1996; 5. Obi, North Maluku, 1998;

6. Banggai, North Maluku, 2000; 7. Manokwari, Papua, 2002;

8. Aceh, Nangroe Aceh Darussalam, 2004; 9. Buru, Maluku, 2006; 10. Pangandaran, West Java, 2006.

(Compiled from Fauzi and Ibrahim, 2002, Fig.1, no. 1-6; Setyawan, 2002, no. 7; and author's data, no. 8-10).

Regards,

Wahyu

North Coast of Banten 1, Tanjung Pontang - Lontar: erosional coastline

Banten Province is situated at wetern part of Java Island. Formerly, the province was part of West Java Province. The following photographs took in 2003 at Lontar area (Figure 1). The Tanjung Lontar - Tanjung Pontang coast is erosional. Before 1925, the coast was depositional. Since 1925, Pamarayan Dam has effectively stoped sediment supply to the coastal water that turned the coast to be erosional (Photo 1-3).

Figure 1. Site map of Tanjung Pontang (west) - Tanjung Kait (east). Large black number indicates relative location the photos. Laut = sea, tanjung = cape, pulau = island.

Photo 1. Face to east toward Lontar village. Erosional coast with erosional platform of stiff mud.

Photo 2. Face to west. Eroded mangrove coast at Lontar.

Photo 3. "Net" of mangroves roots that have lost their substrate.

There are only uncontinuous narrow strip of mangrove along the coast. The villagers have developed ponds extensively at coastal plain and left only about 10 meters mangrove along the coast (Photo 4). At many parts of the coast, the mangroves was eroded away and the ponds as well (Photo 5).

Photo 4. Face to east. Narrow mangrove strip near Tanjung Pontang. Sea wave have eroded away some part of the mangrove and the ponds embankment as well.

Photo 5. Face to west. Eroded ponds that cause zigzagged coastline.

Regards,

Wahyu

Biak Island in Pictures 01

Biak is Pacific island of Indonesia. The island was very important during Second Worl War. In October 2003, I came to the island for the third time. I came to Bosnik where a capital of Bosnik Subdistrict situated before the Biak Tsunami in 1996. The tsunami devastated the town. The following in the pictutes of Bosnik coastal area. I stood at a point at Bosnik's coastline, turned my body around and took the pictures.

Figure 1. Image of eastern Biak island.

Photo 1. Face to west. The long boats are transportation fasility to Padaido islands.

Photo 2. Face to east. The foundation and floor of the swept away houses by the 1996 tsunami.

Photo 3. Face to south. Coastal platform/reef flat in foregroung and reef island at background. Depth of the blue water is more than eight hundred meters.

Photo 4. Face to north. Bosnik market where peoples from Padaido islands trade their goods, mainly fisheries products. Before the 1996 tsunami, Bosnik subdistrict capital was here.

Regards,

Wahyu