οἱ λίθοι κράξουσιν (Luke 19:40)
Flood Geology Challenge #8:
Image from Google Earth. Geological interpretation of author.
The geologic history of this area is an extremely complex one. Indonesia lies at a triple junction of plates. The Indian Ocean and Australia are moving north and colliding and subducting under Indonesia’s southern boundary, the Pacific Plate is sweeping westward at its northern boundary, and this central part of Indonesia marks the southeastern edge of the Asian Plate. All of this tectonism, as the inhabitants will assure you, is very much active today. The island of Sulawesi has one of the most unique shapes on the planet (shaped somewhat like the letter “K”) which is directly attributed to its very complicated geologic history. Below, I will highlight the geologic observations in this area to show the impossibility that central Indonesia is the product of a year-long global Flood.
The geologic history of the Makassar Strait area begins in the Mesozoic. There is field evidence that there have been several collisions of microplates into SE Asia during the Mesozoic. The evidence comes in the form of differences in the sediments between SE Asia and the “exotic terranes” that are now in eastern Borneo and western Sulawesi. Additionally there are ophiolite belts in between that are evidence of the oceanic crust that was obducted (or scooped up) during the plate collisions. These ophiolites are seen in the Meratus Mountains of SE Borneo (the green line and green circles on Borneo on the picture above).
Some time later in the Eocene the North Makassar, South Makassar and East Java Seas began rifting, or spreading apart. Field work has shown the similarities between the sediments of eastern Borneo and western Sulawesi. There are Eocene coals and other terrestrial sediments in both areas attesting to the fact they were joined and that they were exposed above sea level. As the rifting continued the Makassar Strait was born and marine sedimentation commenced. There are fossil reefs that grew on the tilted normal faults of the rift (the green stars on the picture). At this time, the only part of present-day Sulawesi that existed was the central part and the south arm (anything west of the main red north-south strike-slip fault in the heart of the island on the map). It is this section that was rifting away of the Asian plate.
In the Oligocene, as the rifting continued, the small Sulawesi block began to be hit from the east by micro-continental fragments of Australian affinity that were being swept in by the westward moving Pacific Plate. This affinity is suggested by the similarities between the crustal makeup of eastern Sulawesi and Australia and the islands in between. Beginning in the Oligocene and into the Miocene these fragments would collide and attach on to the Sulawesi block. The compression felt from the east inverted some of the normal faults of the rift near the Mangkalihat peninsula of Kalimantan, the western edge of the South Makassar basin, and the East Java Sea. In central and eastern Sulawesi we find the ophiolites (obducted oceanic crust) that we would expect to see as the islands collided and accreted (green circles in Sulawesi on the map). Additionally, as these islands collided with Sulawesi, much of the oceanic crust that was not obducted was subducted and turned Sulawesi into a volcanic arc. The Miocene volcanic sediments span the entire length of Sulawesi from north to south.
As the continental fragments continued to collide, the central Sulawesi highlands were uplifted and a fold belt started to form in western Sulawesi which propagated to the present-day Makassar Strait (blue stars on the map). The collisions also started strike-slip movement along the Palu fault system (red north-south fault in central Sulawesi). This left-lateral fault pushed the eastern part of the island west and then north towards the Celebes Sea. The denser oceanic crust of the Celebes Sea then began to subduct under Sulawesi creating the oddly-shaped north arm of the island. This north arm is a volcanic arc that is now largely extinct except for the eastern tip which is being fed by the westward subduction of the Molucca Sea.
With the collision of the Banggai-Sula block, the major left-lateral strike-slip fault complex on Sulawesi really took off. In the center of the island, the pluton that fed the volcanic arc in the Middle Miocene was uplifted and cooled in the latest Miocene. With the extreme uplift, the cooled granitic pluton was exhumed by the rapid erosion of the mountains. This is evidenced by the abrupt change in the provenance of sediments being deposited in the Makassar Strait. Miocene sediments are mostly volcanoclastics, whereas Pliocene to recent sediments are rich in quartz and are coarser-grained.
Along with the uplift came areas of extreme trans-tension. The Makassar Strait, which was largely a relatively shallow failed rift basin until the Pliocene, rapidly became a pull-apart basin and subsided to water depths of over 2,000 meters. The timing of the subsidence is well documented by good correlations between outcrop data and high-resolution 2d seismic data. The seismic also show that as the Makassar Strait pulled apart and subsided, a gravity induced fold belt continued where the previous Miocene fold belt left off. Huge piles of Pliocene-Pleistocene sediments appear to have extended and formed the spectacular fold belts of the eastern North Makassar Basin. Many of these folds are still sub-seismically active today and can be seen on the bathymetry map (blue stars on the picture above).
I hope it is apparent that, even if we remove the relative age names given in the synopsis above, there is simply too much geologic complexity in the area’s history to be the result of Noah’s Flood. Multiple ocean basins had formed only to be subducted as volcanic arcs and obducted as ophiolites. Even if the fossiliferous Mesozoic sediments were the result of a catastrophic Flood, there is no way to then close the ocean basin and obduct the ophiolites of the Meratus Mountains in southeast Borneo. Then you must completely level off the tops of some of the folds and thrusts to form the spectacular angular unconformities seen on 2d seismic data in the East Java Sea. This must have occurred prior to the rifting of the Makassar Strait. The terrestrial and coal beds and reefs seen onshore and just offshore in the area must be the product of sub-areal exposure and shallow calm seas respectively, not the torrential cataclysm so often claimed by Global Flood advocates. After the extension of the Strait came the compression events as the micro-continental blocks began to slam into eastern Sulawesi. Subsequent to that compression was the exhumation of the earlier volcanic pluton which clearly sourced the sediments of the magnificent fold belts of the eastern Makassar Strait.
As if the geologic history was not too difficult to explain with a global Deluge, the biological history would deal a fatal blow to the theory. The Makassar Strait presently serves as a flora and fauna boundary between the Asian type to the west and the Australian type to the east. Only the deep water of the Strait could account for this boundary. If the Makassar Strait were the product of the Flood, there would simply be no way that the Australian animals could have migrated from the ark to the Australian continent where they live today. There can be only one explanation: the animals migrated there before the Strait formed, and they were unaffected by the Flood. If they were unaffected by the Flood, then the Flood MUST have been local in extent.
Copyright 2009 The Stones Cry Out. All rights reserved.