OVERVIEW

Representing the most comprehensive palynological dataset currently available for the Triassic of the Bedout Sub-basin, this study enables the identification of over 50 correlative events through the key Early-Middle Triassic T. playfordii interval.

This multi-client study provides far greater resolution than the existing 3 zonal subdivisions available in all other open-file datasets, and greatly refines the palaeoenvironmental understanding of one of the North West Shelf’s most promising oil plays, enabling better exploration targeting and reservoir prediction.

BACKGROUND

The Bedout Sub-basin, located offshore Western Australia, has emerged as a significant focus for hydrocarbon exploration following notable discoveries in recent years. The 2018 discovery of the Dorado oil field marked the largest oil find on the North West Shelf in three decades, estimated to contain approximately 162 million barrels of light oil and condensate, along with significant gas resources.

Subsequent discoveries, such as the Pavo-1 well in 2022, have further demonstrated the region’s potential, revealing a net oil pay of 46 meters with excellent reservoir characteristics. These findings have positioned the Bedout Sub-basin as a promising area for future exploration and development.

However, it was quickly apparent that the palynology of the TR10 interval in the Bedout Sub-basin (and likely across the North West Shelf) needed a detailed review. Many of the biostratigraphic markers applied to this interval were inherited from eastern Australian palynological schemes and were often unreliable or of low confidence. Much of the data also related to quick look analyses and needed full quantitative re-study.

DETAILS

Given the substantial resource potential, a comprehensive palynological study was undertaken to enhance the biostratigraphic resolution and paleoenvironmental understanding of the Triassic formations within the Bedout Sub-basin.

For this multi-client study, quantitative palynological analysis of the Triassic of fifteen wells from the Bedout Sub-basin, Roebuck Basin, has been carried out, incorporating the analysis of more than 800 new and existing palynological samples over previously identified Triassic intervals

The datasets collected over the last 8 years represent, by far, the most comprehensive palynological review of the TR10 play interval, with particular emphasis on the T. playfordii Zone. However, where present, all of the Triassic has been re-studied or new slides prepared. This has resulted in a high-definition regional event biostratigraphy (with up to 29 subzones/events recognised across the T. playfordii Zone alone).

Furthermore, a new interpretation of the Jurassic/Triassic boundary was noted in several wells (samples previously assigned to the Triassic are now considered to represent Triassic reworking into an Early Jurassic succession).

This study aims to provide critical insights that will support ongoing and future exploration activities, ensuring more accurate stratigraphic correlations and reservoir characterizations in this promising hydrocarbon province.

Well list:

  • Dorado 1
  • Dorado 2
  • Dorado 3
  • Roc 2
  • Roc 1
  • Roc South 1
  • Phoenix South 1
  • Phoenix South 2
  • Phoenix 1
  • Phoenix 2
  • Lagrange 1
  • Bruce 1
  • Poissonnier 1
  • Keraudren 1
  • Bedout 1

Figure 1: Well locations within the Bedout Sub-basin.

The Triassic of the Bedout Sub-basin MGPalaeo

DELIVERABLES

  • New local high-resolution palynological event stratigraphy
  • Fully quantitative Triassic palynological datasets
  • One consistent palynological zonation scheme applied to all wells
  • Tabulated palynological sample summaries
  • Stratigraphic summary chart for each well, including age, palynological zones and events, lithostratigraphy and sample data points, all set against wireline log data
  • Multi-well correlation panels.

For more information on this detailed study, including pricing, please contact us.

MGPalaeo has also carried out a comprehensive core study to provide greater insight into the depositional models of this emerging petroleum system.