INPEX has drilled seven deepwater wells in offshore remote area in the Southeast Asia. We have experienced a lot of lessons learnt from the perspective of the remote area and the deepwater operation. In this paper, four main topics are described which are utilization of material warehouse vessel to support the remote drilling operation, difficulties to utilize the semi-submersible drilling rig with marginal specification for water depth, operational difficulty at 13-3/8″casing stuck, and successful operations to tie back 9-5/8″liner with casing.
In 2004, Japan Petroleum Exploration (JAPEX) entered into a service contract (SC) No.46 with the Department of Energy (DOE) and agreed to drill an exploratory well in a block located in Tanon Strait between Cebu and Negros Islands in Philippines. After seismic data acquisition was completed, it turned out that Tanon strait was designated as a protected seascape by National Integrated Protected Area Act and JAPEX had to go through environmental impact assessment process to obtain Environmental Compliance Certificate (ECC) to drill a well. Environmental study was conducted following EIA guideline and extensive Information, Education and Communication (IEC) campaign was carried out under co-operation with DOE. ECC was issued in March 2007 and the drilling operation was conducted through November 2007 to February 2008. This paper outlines the process to obtain ECC for drilling a well in protected area in Philippines and also introduces severe borehole instability (pack-off) problems encountered during actual operation.
Integrating knowledge and data gained from operational experience of Japan Drilling Co., ltd. in Iranian waters, offshore drilling data service, internet with general analysis on middle east energy trends, offshore drilling market and rig utilization and other industry statistics, this paper addresses Oversea Project's Environments and Problems, which is the theme of this symposium.
The Ishikari-Hidaka sedimentary basin which ranges from Iwamizawa to the coastal area of Hidaka District, Hokkaido, is occupied by thick Neogene sedimentary rocks. These include Miocene rocks that consist mainly of sandstone, mudstone, interbedded sandstone and conglomerate (gravity flow deposits), siliceous hard mudstone, and diatomaceous mudstone, showing various vertical and lateral changes in lithofacies. We have surveyed the Miocene Takinoue, Kawabata, Iwamizawa and Oiwake Formations exposed in the southern part of Iwamizawa City and have examined radiolarian assemblages of these formations to discuss the temporal sedimentary history of the basin. Radiolarian fossils from the examined geologic section are indicative of the Dendrospyris? sakaii Zone to Lychnocanoma magnacornuta Zone, suggesting that the Kawabata, Iwamizawa, and Oiwake Formations were deposited during the Middle Miocene (∼15 to ∼12.2 Ma), the late Middle Miocene (∼12.2 to 11.7 Ma), and the Late Miocene (after 11.7 Ma), respectively. Correlation between the study area, Yubari area and Hobetsu area revealed diachronous nature in change from domination of coarse gravity flow deposition of the Kawabata Formation to biosiliceous fine-grained facies of the Iwamizawa Formation.