71
continental glaciers, and which are thought to be relatively tectonically stable, show
similar Holocene sea-level records as a result of this process.
Another substantial influence on the physiography of much of Malaysia’s coastal
zone is its situation on relatively tectonically stable continental crust. Peninsular
Malaysia (Fig. 5.2) has been widely considered to be a tectonically stable far-field
(far from polar ice sheets) region. This relatively tectonically stable area, known as
the Sundaland (it is centered on the Sunda Shelf), contrasts markedly with the zones
of intense tectonic activity that surround it, for example, along the west coast of
Sumatra (Fig. 5.1) where the 2004 earthquake caused horrific tsunami-related damage and loss of life (see the chapter by Hawkes).
A tectonically stable far-field region is an advantageous place to study sea level
because the coastal zone is considered to be neither going up nor down, except in
response to continental levering. This makes global changes in sea level easier to
decipher, while in tectonically active areas, vertical movement of the land can substantially complicate our ability to unravel the global sea-level record. The Malaysian
Borneo states of Sarawak and Sabah, particularly Sabah (Fig. 5.3), are tectonically
active, resulting in a very different sea-level story from that of the peninsula.
Fig. 5.1 Map of the Southeast Asia region shows the locations of Peninsular Malaysia, Malaysian
Borneo, Sunda Shelf and areas of major tectonic activity adjacent to the relatively tectonically
stable southern extension of Asian continental crust called Sundaland (outlined with white dashed
line). (Basemap from https://www.maps.ngdc.noaa.gov; modified and labelled by the author)
5 A Different Kind of Sea-Level Story from Malaysia
continental glaciers, and which are thought to be relatively tectonically stable, show
similar Holocene sea-level records as a result of this process.
Another substantial influence on the physiography of much of Malaysia’s coastal
zone is its situation on relatively tectonically stable continental crust. Peninsular
Malaysia (Fig. 5.2) has been widely considered to be a tectonically stable far-field
(far from polar ice sheets) region. This relatively tectonically stable area, known as
the Sundaland (it is centered on the Sunda Shelf), contrasts markedly with the zones
of intense tectonic activity that surround it, for example, along the west coast of
Sumatra (Fig. 5.1) where the 2004 earthquake caused horrific tsunami-related damage and loss of life (see the chapter by Hawkes).
A tectonically stable far-field region is an advantageous place to study sea level
because the coastal zone is considered to be neither going up nor down, except in
response to continental levering. This makes global changes in sea level easier to
decipher, while in tectonically active areas, vertical movement of the land can substantially complicate our ability to unravel the global sea-level record. The Malaysian
Borneo states of Sarawak and Sabah, particularly Sabah (Fig. 5.3), are tectonically
active, resulting in a very different sea-level story from that of the peninsula.
Fig. 5.1 Map of the Southeast Asia region shows the locations of Peninsular Malaysia, Malaysian
Borneo, Sunda Shelf and areas of major tectonic activity adjacent to the relatively tectonically
stable southern extension of Asian continental crust called Sundaland (outlined with white dashed
line). (Basemap from https://www.maps.ngdc.noaa.gov; modified and labelled by the author)
5 A Different Kind of Sea-Level Story from Malaysia