BRISBANE, Australia, March 6, 2018 /PRNewswire/ -- Orocobre Limited (ASX: ORE, TSX: ORL) ("Orocobre" or "the Company") is pleased to provide an update on the results of the pumping test conducted on CAU07 in the NW Sector of the Cauchari JV properties located in Jujuy Province, Argentina.
The exploration program is being managed by JV partner Advantage Lithium Corp. ("Advantage Lithium") (TSX Venture: AAL) (AVLIF) who hold 75% of Cauchari. Orocobre owns 33% of Advantage Lithium's issued capital.
- Positive results from CAU07 four-step pumping test suggest rates as high as 36 l/s are achievable
- CAU07 constant rate pumping test conducted at 17 l/s over 48 hours with flow limited by the pump capacity
- Good brine chemistry with 19 samples taken over the pumping test averaging 601 mg/l Lithium and 4,853 mg/l Potassium with a Mg/Li ratio of 2.6:1
- Hole CAU13 in the SE Sector of Cauchari successfully intersected a sequence of sandy sediments below 400 m; adding additional brine volume in this area for the upcoming resource estimate
Cauchari NW Sector – CAU07 pumping test results
CAU07 was drilled to a depth of 343 m in the north of the NW Sector of the property. This drill hole intersected some clay units and material thicknesses of sand and gravel dominated units with favourable porosity and permeability characteristics. The hole has screened intervals between 135 m and 325 m depth.
A variable flow rate pumping test (step test) was conducted on the well at flow rates from 3.5 to 17 l/s, limited by the capacity of the pump used in the pumping test. The well has a high specific capacity and the test suggests that a flow rate of approximately 36 l/s may be feasible. The pumping test results confirm the excellent hydraulic characteristics in the NW Sector which are favourable for future brine extraction. The constant rate pumping test was conducted at a flow rate of 17 l/s -20 l/s over a period of 48 hours. 19 brine samples were taken during the pumping test with the average concentration of 601 mg/l Lithium and 4,853 mg/l Potassium and a low Mg/Li ratio of 2.6:1. The Mg/Li ratio is very similar to that in the producing Olaroz lithium project.
All brine analyses were completed in a commercially accredited laboratory in Argentina, accompanied by QA/QC samples, comprising brine standards and duplicates1. This information confirms the importance of the sand dominated units that Advantage Lithium has been exploring for.
Orocobre Managing Director Mr. Richard Seville commented, "The exploration programme being managed by our partner Advantage Lithium is moving ahead with strong results. This latest pump test shows high grades, high flow rates and confirms the potential of the north west sector. Hole CAU07 is the first pump test in this area and the results reflect the quality of the sandy aquifers present there. Drilling continues in both the NW and SE Sectors and we look forward to producing an upgraded resource for the NW and SE Sectors once the drilling is completed."
Cauchari SE Sector - CAU013 drilling
CAU13 was drilled to a depth of 449 m in the west of the SE Sector of the project. CAU13 intersected a sequence of clay, silt and some sand and halite to 400 m depth and a more sandy interval from 400 m to the end of the hole. It is not clear to what depth the deeper sand unit extends at this drilling location. The drill rig has now moved to deepen hole CAU12, which is located 2 km to the SW. Brine analyses are awaited from drilling of CAU13 and will be released when they become available.
Additional Cauchari drilling
Upon completion of diamond hole CAU18 in the NW Sector the rig will drill hole CAU17 2.5 km further to the west. In the SE Sector the second diamond drill rig will deepen CAU12 to explore for the deep sand and gravel unit and then commence drilling CAU14 located some 5 km further to the northeast.
For more information please contact:
Investor Relations Manager
T: +61 7 3871 3985
M: +61 418 783 701
Competent Persons Statement
The information in this report that relates to exploration reporting at the Cauchari JV project has been prepared by Mr. Murray Brooker. Murray Brooker is a geologist and hydrogeologist and is a Member of the Australian Institute of Geoscientists. Mr. Brooker is an employee of Hydrominex Geoscience Pty Ltd and is independent of Orocobre. Murray has sufficient relevant experience to qualify as a competent person as defined in the 2012 edition of the Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. He is also a "Qualified Person" as defined in NI 43-101. Murray Brooker consents to the inclusion in this announcement of this information in the form and context in which it appears.
About Orocobre Limited
Orocobre Limited (Orocobre) is a dynamic global lithium carbonate supplier and an established producer of boron. Orocobre is dual listed on the Australia and Toronto Stock Exchanges (ORE.AX), (ORL.TO). Orocobre's operations include its Olaroz Lithium Facility in Northern Argentina, Borax Argentina, an established Argentine boron minerals and refined chemicals producer and a 35% interest in Advantage Lithium.
For further information, please visit www.orocobre.com
1 Assaying completed at Alex Stewart Laboratories in Jujuy city, Argentina under strict QA/QC protocols.
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