Central Java city and its surrounding regencies have formed a separate special region (equivalent to a province) since Indonesian independence, administrated separately. Located in the middle of the island of Java, the Central Java province is bordered by West Java and East Java provinces. A small portion of its south region is the Yogyakarta Special Region province, fully enclosed on the landward side by the Central Java province. To the north and the south, the Central Java province faces the Java Sea and the Indian Ocean. Central Java includes offshore islands such as Karimun Jawa Islands in the north, and Nusakambangan in
Kermadec Trench is 72–80 Ma near the Louisville seamounts at the northern end and more than 100 Ma near Hikurangi Plateau at the southern end. There are no seamounts on the sea-floor near the Kermadec Trench except one sitting on the trench slope at which has been dated to 54.8±1.9 Ma. The Hikurangi Plateau formed part of the Ontong-Java-Manihiki-Hikurangi large igneous province (LIP) during the so-called Greater Ontong Java Event 120 . The Manihiki Plateau is currently subducting under the southern part of the Kermadec Arc but most of it has already been subducted. The LIP-arc collision occurred north of its present