SULU SEA BASIN PLUS SPRATLY ISLANDS MULTI-RING BASIN: DOUBLET CRATER RESULTING FROM A MIDDLE MIOCENE BINARY OBLIQUE IMPACT?
1) A global Middle Miocene impact layer/spherule bed has not been identified. Spherule layer should be tens of cm thick based on conventional rock vapor scaling [1,2].
2) The Middle Miocene Disruption should have been a severe (not minor) extinction event .
3) Impact basins of Sulu Sea Basin size are not expected in the Phanerozoic .
To confirm or rule out impact origin search for and identify:
1) global impact layer in continuous Middle Miocene sedimentary sequences.
2) Middle Miocene course ejecta layer proximal to these structures in oil and exploratory well cores from the South China and Celebes seas.
3) impactites in exploratory drill cores from the Spratlys.
4) high pressure and/or shocked mineral phases in Sulu Sea basin rim ophiolites: Can ophiolitic diamonds be found in chromitites from Palawan and Sabah ?
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