May 2013, we completed diamond drilling of ~450m of sedimentary rocks from the 2.45 to 2.2 Ga old Turee Creek Group, Hamersley Basin, Western Australia. The objective was to intercept key sedimentary successions  associated with the rise of atmospheric oxygen between the 2.45 to 2.32 Ga (Great Oxidation Event, GOE).

Figure 1 : Geological Map of Western Australia showing the drilling core site of Turee Creek

REASONS FOR DRILLING

The Turee Creek Group was choosen because it represents the only continuous stratigraphic sedimentary section worldwide hosting the Great Oxydation Event and the first global glaciation (Huronian glaciation), thus providing a unique opportunity to examine the nature, rate, and duration of the rise of atmospheric oxygen on Earth. The Turee Creek Group represents the uppermost section of the Hamersley Basin. It has a total thickness of about 4 km, shallowing upwards from banded iron formation (BIF) of the underlying Boolgeeda Iron Fm. forming the top of the Hamersley Group, to clastic sedimentary rocks, glacial diamictites of the Meteorite Bore Member and stromatolitic carbonates of the Kazput Formation.

Figure 2: Stratigraphic section of the Turee Creek Group.

DRILLING SITES

The TCDP was performed during April and May 2013.  Three drilling sites were chosen in three different stratigraphic intervals of the Turee Creek Group.

- TCDP1 (- 22°48’31.00″S – 116°47’15.90″E) intercepts the contact between the underlying banded iron formation of the Boolgeeda Formation (Hamersley Group), and the overlying Kungara formation of the Turee Creek Gp.

- TCDP2 (22°50’49.70″S – 116°52’27.70″E) intercepts the base of diamictites of the Meteorite Bore Member and part of the underlying mudstone, siltstone and carbonate-bearing stromatolite of the Kungara Formation.

- TCDP3 (22°52’15.90″S – 116°56’46.40″E) intercepts  the base of the Kazput Formation and underlying Koolbye quartzites.

Total depth of drilling is 746 m, with 292 m RC collar and 454 m NQ diamond drilling.

DRILLING TEAM

The drilling team consisted of Pascal Philippot and Elodie Muller (IPGP) and  Martin Van Kranendonk (University of New South Wales). Paul Van Loenhout of “Mount Magnet” and his crew are thanked for their professional work and enthusiasm in obtaining the drillcore. Drilling was performed as part of a joint scientific research project between IPGP and the Geological Survey of Western Australia

FUNDING

Funding for drilling was provided by the Labex UnivEarthS of the PRES Sorbonne Paris Cité Consortium as part of the Frontier Project “Earth as a living Planet: from Early ages to present day dynamics”