Table 1 List of samples collected in the PSP providing evidence for a pre-Eocene proto-PSP
Region (see n° in Fig. 3) | Sample location | Sample nature and dated material | Estimated age | Source |
|---|---|---|---|---|
Izu-Bonin fore-arc | ||||
1 | Dive samples (YK11-07) 32° 14' N–141° 39' E | Andesite, diorite | Cretaceous ~100 Ma (U-Pb) + Paleozoic and Proterozoic detrital zircons | Tani et al. 2012 |
Tani and Myojinsho 2011 | ||||
2 | Sample 6 K1152 27° 19' N– 143° 00' E | Two pillow basalt lavas beneath gabbro | Middle Jurassic 159.4 ± 0.9 Ma (40Ar/39Ar) | Ishizuka et al. 2011b |
Ishizuka et al. 2012 | ||||
Mariana fore-arc | ||||
3 | Site 460, DSDP 60 17° 40' N–147° 35' E | Pebble conglomerate with Calpionella alpina | Late Jurassic to Early Cretaceous (~130–140 Ma) | Azéma and Blanchet 1981 |
3 | Site 460 17° 40' N–147° 35' E | Reworked radiolarians | Upper Cretaceous (Campanian, ~72–83 Ma) | Hussong and Uyeda 1981 |
3 | Site 461 17° 46' N–147° 41' E | Reworked radiolarians | “Cretaceous” (~65–135 Ma) | Hussong and Uyeda 1981 |
4 | Dredges 19° 37' N–147° 04' E | Radiolarian cherts | Lower Cretaceous Valanginian ~97–112 Ma and Albian 131–138 Ma | Johnson et al. 1991 |
4 | Dredges 19° 37' N–147° 04' E | Foraminifers in cherts | Lower Cretaceous (Aptian to Albian ~96–113 Ma) | Johnson et al. 1991 |
4 | Dredges 19° 37' N–147° 04' E | MORB metabasalt | Upper Cretaceous 85 Ma (K-Ar) | Johnson et al. 1991 |
4 | Dredges 19° 37' N–147° 04' E | Highly metamorphosed alkali basalt | Upper Cretaceous 71 Ma (K-Ar) | Johnson et al. 1991 |
WPB | ||||
5 | Site 290 east of KPR 17° 44' N–133° 28' E | Reworked foraminifers in a volcaniclastic apron | Cretaceous | Ingle et al. 1975 |
KPR | ||||
6 | Dredge in southernmost part of KPR on a ridge between Palau Trench and KPR | Mafic schists of amphibolite to greenschists facies | May have similar age and origin to Cretaceous Daito Ridge | Ishizuka et al. 2012 |
ADO region | ||||
7 | Dive samples (YK10-04) | Gabbroic, granitic and metamorphic rocks | Jurassic to Cretaceous magmatic zircons | Tani et al. 2012 |
Tani 2010 | ||||
25° 54' N–133° 54' E | ||||
27° 53' N–131° 51' E | ||||
27° 56' N–132° 02' E | ||||
Amami Plateau | ||||
7 | Dredge 11-17-1 28.07° N–131.63° E | Hornblende tonalite | Lower Cretaceous 69.5 Ma (K/Ar)–117.0 ± 1.1 Ma (40Ar/39Ar) | Matsuda et al. 1975 |
Tokuyama 1985 | ||||
Hickey-Vargas 2005 | ||||
7 | Dredge 11-17-5 28.08° N–132.02° E | Hornblende tonalite | Lower Cretaceous 75.1 Ma (K/Ar)–115.8 ± 0.5 Ma (40Ar/39Ar) | Matsuda et al. 1975 |
Tokuyama 1985 | ||||
Hickey-Vargas 2005 | ||||
7 | Dredge 11-9-33 | Basalt | Upper Cretaceous 82.4 and 85.1 Ma (K/Ar) | Matsuda et al. 1975 |
Tokuyama 1985 | ||||
Daito Ridge | ||||
8 | Short core or dredge ~25.9° N–135.2° E | Andesite | Lower Cretaceous 116.9 ± 0.9 Ma (40Ar/39Ar) | Ishizuka et al. 2011a |
9 | Short core or dredge ~26.0° N–133.1° E | Andesite | Lower Cretaceous | Ishizuka et al. 2011a |
118.9 ± 0.4 Ma (40Ar/39Ar) | ||||
Oki-Daito Ridge | ||||
10 | Dredge (unknown exact location) | Alkali basalt | Limit Upper Cretaceous-Paleocene 65 Ma | Okino and Kato 1992 |
Huatung Basin | ||||
11 | Dredged sample RD19 20.40° N–121.47° E | Gabbro | Lower Cretaceous | Deschamps et al. 2000 |
121.2 ± 4.6 Ma (40Ar/39Ar) | ||||
12 | Dredged sample RD20 21.49° N–122.69° E | Gabbro | Lower Cretaceous | Deschamps et al. 2000 |
123.2 ± 7.8 Ma (40Ar/39Ar) | ||||
13 | YehYu Creek sample on Lanyu Island 22° N–121.55° E | Red chert float radiolarian | Lower Cretaceous (Barremian ~113–117 Ma) | Deschamps et al. 2000 |
Philippine archipelago | ||||
14 | Outcrops | Ophiolitic suites | Cretaceous | Yumul 2007 |