Adam Vonk explains that we are more likely to find natural gas in the Taranaki basin. This is because the source rock is mostly coal, which is generally considered to be a gas-producing source rock. There is a small amount of oil in the Taranaki region, but oil fields such as Tui oil field are often smaller than gas fields such as Maui.
Points of interest:
A source rock is also called a source bed and refers to an organic sediment or rock that contains and can release oil or gas when it is heated during burial. Note that sedimentary rocks are formed when sediments are deposited and then compacted under pressure.
Taranaki basin is generally considered to be a gas-prone basin, but having said that, there is oil also found in Taranaki. It all comes down to the type of source rock we have in Taranaki.
So generally, the source rocks in Taranaki are coals, and they’re generally considered to be gas-producing type source rocks. But having said that, there are some instances where they have produced oil, which has later been trapped in reservoirs.
So some of our biggest hydrocarbon fields like the Maui field and the Kapuni field are gas fields. There are several other oil fields being developed at the moment, like the Tui area oil field, and there’s one called Maari, which actually sits towards, closer to the South Island.
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