- Mbelele sample calculated free-air composition of 2% to 3% helium
- Mbelele-2 wireline logging and sampling program successfully completed
- Excellent reservoir parameters and flow potential
- Total net reservoir thickness of 163m, a 243% increase over pre-drill estimates
- High mobility, representing very high flow potential similar to Mbelele-1
- Mbelele-2 cased and suspended for future flow testing
- Focus to now shift to appraisal and early monetisation
Noble Helium has successfully completed wireline logging and sampling at the Mbelele-2 well, at the Company’s 100% owned North Rukwa Helium Project in Tanzania.
CEO Justyn Wood, commented:
'Our maiden drilling program has been an incredible success, both operationally and in confirming the potential for a significant helium resource at Mbelele. Multiple data points throughout the drilling campaign point to a prolific helium system: a probable 10-15 metre column of nitrogen and helium at the crest, helium-rich downhole samples calculated at 2-3% helium in exsolved gas and helium-rich gas bubbles in the drilling mud at multiple depths in both wells.
These results also significantly de-risk the balance of the Company’s North Rukwa acreage, with clear evidence we are in a globally unique and prolific helium producing system, supporting the Company’s well-researched thesis that the North Rukwa rift basin has the potential to emerge as a globally significant primary helium province.
The new reservoir thicknesses and other acquired data will now be applied to updating the reservoir models and other technical work with a view to satisfying the SPE-PRMS requirements for declaration of a discovery.
On behalf of the Board, we are extremely delighted with these initial results and look forward to providing further updates after integrated analysis of the information gathered from Mbelele-1 and Mbelele-2.'
Mbelele-2 was spudded on 16 November at 0100hrs local time and similar to Mbelele-1 soon encountered helium-enriched gas bubbling in the mud system, initially at 140mMD, which may correlate laterally to the formation at Mbelele-1 that contained the probable nitrogen-helium gas cap at 85mMD. This bubbling with helium shows repeated at multiple intervals throughout the entire drilled section to immediately above Total Depth of 763.5mMD.
These results provide a clear indication of high levels of gas saturation and availability of helium at Mbelele, in line with the Company’s growing body of evidence and conviction that the North Rukwa Basin hosts a prolific helium system.
Preliminary interpretation of the Mbelele-2 open-hole section, drilled from casing point at 250mMD to top basement at 722mMD, shows the well encountered approximately 163m of stacked net reservoir in the Middle and Lower Lake Beds (Table 1).
This total net reservoir thickness of 163m compares very favourably to the 47.5m net reservoir encountered at Mbelele-1 in the Upper and Middle Lake Beds and is significantly greater than the pre-drill estimates (~20m in this interval).
These reservoirs are again of excellent quality. Petrophysical evaluation of SLB’s wireline logs demonstrate good to very good porosities and permeabilities, which are slightly lower than Mbelele-1 but significantly thicker. High mobilities, similar to Mbelele-1 and consistently >100mD/cP and up to 780 mD/cP, provide very high flow potential.
The initial Mbelele-2 sample results are extremely encouraging and appear consistent with the Mbelele-1 results below. Limitations with the onsite facilities require that the helium concentrations from the samples recovered to surface be verified in the laboratory.
Since gathering the original air-contaminated Mbelele-1 samples, the Company has undertaken work with the University of Queensland to assist in calculating the air-free helium concentrations and can advise a Company-estimated air-free helium percentage of the exsolved gas of between 2% and 3% across all samples at Mbelele-1. The balance of the gas is Nitrogen with no evidence of CO2 or hydrocarbons. This is of course subject to ultimate confirmation from the full laboratory analysis and the Mbelele-1 samples are currently enroute to labs in the US and Australia for independent analysis, with the Mbelele-2 samples now in close pursuit.
The Company has been in discussion with NSAI in relation to SPE-PRMS requirements for declaring a discovery and also the data required for our early monetisation opportunity. The next steps in order to be in a position to be able to declare a discovery are within reach - results of the lab analysis, updating the Company’s Petrel TM model with all of the upgraded data acquired from Mbelele-1 and Mbelele-2, completion of the reservoir flow modelling in partnership with University of Queensland with the potential addition of in-field flow testing.
Collectively, these results point to a potentially very significant helium resource resident and producible from within the Mbelele structure’s reservoirs. Planning is now underway to move as quickly as possible to flow testing Mbelele-2 in the Lake Beds and test the potential shallow gas column identified at Mbelele-1. This information will be critical in executing our early monetization strategy.
With Wireline logging and testing now completed at the current well, Mbelele-2 has now been cased and suspended for future flow testing and as a potential future producer well. The Marriott rig #16 is being stacked onsite at Mbelele-2 to enable rapid return to Operation as required.
Mbelele is contains Neogene-aged Lake Beds and is located on the western side of the North Rukwa Basin, some 190 km northwest of Mbeya and 825km inland from Tanzania’s main port city of Dar es Salaam.
See also, ASX release December 6 2023: Mbelele results clarification
Background
The North Rukwa Project is the Company’s flagship project located in the Rukwa Basin in southwest Tanzania, which comprises twelve granted Prospecting Licences (PL) covering a combined area of approximately 1,467km2.
The Rukwa Basin occupies a 300km-long rift segment of the East African Rift System, located between Lake Tanganyika and Lake Nyasa (Malawi) in southwest Tanzania. With the benefit of legacy oil and gas exploration data that has accelerated the Project, Netherland Sewell and Associates Inc (NSAI) of Houston has independently certified a summed un-risked mean Prospective Helium Resource of 176 billion cubic feet (equivalent to approximately 30 years’ supply) across 10 leads in the North Rukwa.
With helium measured in rift-related hot springs at up to 10.6% (versus 0.3% commercial cutoff in onshore gasfields in the USA), the Rukwa Basin alone has the potential to be the world’s third largest helium reserve behind USA and Qatar.
Click here for further info., including a map showing North Rukwa Helium PLs and Leads to date
Source: Noble Helium
