Gas and condensate field
Bonaparte Basin, Timor Sea, Australia
Between 130m and 350m
ConocoPhillips Australia Exploration (37.5%), SK E&S Australia (37.5%) and Santos Offshore (25%)
ConocoPhillips Australia Exploration
Barossa project is a gas and condensate field located in the Bonaparte Basin of the Timor Sea offshore Australia, in a water depth between 130m and 350m.
The field is being developed along with the nearby Caldita field under the Barossa offshore development project. The project is owned by the Barossa-Caldita joint venture, which comprises ConocoPhillips Australia Exploration (37.5%), SK E&S Australia (37.5%) and Santos Offshore (25%).
ConocoPhillips is serving as the operator and submitted a development proposal to the National Offshore Petroleum Safety and Environmental Management Authority (NOPSEMA).
The proposal was accepted by the NOPSEMA in March 2018.
First gas from the offshore project is expected to be achieved in 2023 with an estimated annual production rate of 3.7 million tonnes (Mt) of liquefied natural gas and 1.5 million barrels of gas.
The project is expected to have a life of approximately 25 years from its first gas.
The final investment decision on the project is expected by the end of 2019.
Barossa and Caldita discovery
Barossa was discovered in 2006 with the drilling of the Barossa-1 exploration well to a depth of 4,310m.
Two drill stem tests were conducted on the well, which confirmed the presence of gas. One test flowed at the rate of 30.1 cubic feet a day, while the second flowed at a rate of 0.8 million cubic feet a day.
The Caldita field was discovered in 2005 by the Caldita-1 well and subsequently appraised by the Caldita-2 well in 2007.
Appraisal on Caldita-Barossa
The Barossa field has been appraised by a total of five wells. The first three wells, Barossa-2, Barossa-3 and Barossa-4, were part of a three-well appraisal programme that was completed in 2015.
Barossa-2 struck 88m of net pay in the Upper Elang, Lower Elang and Plover reservoirs, while Barossa-3 encountered 104m of net pay and Barossa-4 further confirmed the potential of the field.
A second appraisal programme consisting of two wells, Barossa-5 and Barossa-6, was completed in June 2017. The two wells confirmed reservoir productivity and provided critical data for field development planning.
Barossa-6 struck gas and condensate in the Elang reservoir located between depths of 4,103m and 4,144m. Tests conducted on the well resulted in a flow rate of 65 million standard cubic feet (Mmscf) a day.
Barossa project development details
The Barossa-Caldita project is planned for development via a permanently moored floating, production, storage and offloading (FPSO) facility.
A total of 10-25 subsea production wells are planned to be drilled across the two fields and a production gathering system will transfer the produced hydrocarbons to the FPSO through in-field flowlines.
The Barossa field will be developed first, while the Caldita Field will be developed as a subsea tie-back to the FPSO at a later date.
A fibre-optic cable is scheduled to be laid between the FPSO and Darwin to allow the remote operation of the facility.
Hydrocarbons export and processing
Natural gas and condensate produced from the field will be separated by the FPSO, and the condensate will then be offloaded directly into tankers.
The dry gas will be transported onshore to the Darwin Liquefied Natural Gas (LNG) facility via a 260km-to-290km-long subsea gas export pipeline, featuring a diameter ranging between 24in and 28in, for further processing.
The exact route of the pipeline is yet to be identified, though it is proposed to tie-in with the Bayu-Undan to Darwin gas export pipeline.
Barossa project is intended to replace production from the Bayu-Undan field following its expected depletion in 2022.
Contractors involved in the Barossa project
A consortium of TechnipFMC and Samsung Heavy Industries (SHI) was awarded a front-end engineering and design (FEED) contract for the project’s floating, production, storage and offloading (FPSO) vessel in June 2018.
MODEC International was awarded a FEED contract by ConocoPhillips Australia for the FPSO vessel in July 2018.
The final FEED contractor will be selected after a design competition between the two groups.
INTECSEA, a subsidiary of Worley Parsons Group, was awarded a FEED contract by ConocoPhillips for the subsea infrastructure of the Barossa project in June 2018. The scope of the contract includes the supply of engineering services for the umbilicals, risers, infield rigid flowlines, and a gas export pipeline from Bayu-Undan to Barossa.