VANCOUVER, BC / ACCESS Newswire / March 11, 2026 / Marimaca Copper Corp. ("Marimaca Copper" or the "Company") (TSX:MARI)(ASX:MC2) reports results from the Pampa Medina deposit, located at low altitude approximately 28km east of the Company's Marimaca Oxide Deposit ("MOD") (Figure 1). Drilling intersected high-grade manto-type copper-silver mineralization in significant step-outs west from previous step-out drilling and demonstrates the western continuity of the favourable, mineralized sediment horizons. The Company has not yet completed initial metallurgical programs at Pampa Medina and is therefore not reporting copper equivalent grades at this time. Silver by-products are common in Chilean manto-type deposits, including the nearby Mantos Blancos (Capstone Copper) and Cachorro (Antofagasta Minerals) deposits.
Highlights
Following the success of the 30,000m Phase II program - Marimaca will expand to 10 drill rigs at Pampa Medina with target meterage of 100,000m in 2026, subject to results-based stage-gates
SWRD-02 drilled approximately 600m west of previous drilling (SMRD-24) intersected high-grade mineralization across a sandstone and tuff sequence
74m of 1.21% Cu and 7.9gpt Ag from 520m, including
12m of 2.07% Cu and 17.2gpt Ag from 532m
SMRD-34, drilled in between SWRD-02 and SMRD-24 on a 300m spacing, intersected mineralization in both the near-surface upper volcanics and the lower sediments
36m of 1.08% Cu and 13.8gpt Ag from 158m, including
6m of 3.01% Cu and 37.3gpt Ag from 166m
24m of 1.37% Cu and 12.2gpt Ag from 600m, including
10m of 2.58% Cu and 25.8gpt Ag from 606m
SWRD-01, drilled 300m north of SWRD-02, and 300m west of previously released SMRD-16, also intersected the high-grade lower manto in the interbedded siltstone, sandstone and tuff sequence
38m of 1.43% Cu and 11.8gpt Ag from 694m, including
8m of 2.11% Cu and 15.5gpt Ag from 694m, and
14m of 1.86% Cu and 19.3gpt Ag from 718m
SWRD-04 intersected the upper and lower manto, however mineralization was affected by both pre-and-post mineral dyking
16m at 1.00% Cu and 5.9gpt Ag from 332m, including
4m at 2.51% Cu and 14.5gpt Ag from 338m
8m of 1.17% Cu and 5.0gpt Ag from 368m
Broad lower manto significantly affected by pre-and post-mineral intrusions:
10m of 0.71% Cu and 6.4gpt Ag from 660m
4m of 1.06% Cu and 8.5gpt Ag from 706m
4m of 1.08% Cu and 17.0gpt Ag from 820m
6m of 0.85% Cu and 9.7gpt Ag from 836m
SWRD-03 was affected by splays of the north-south Ancla Fault System zone and intersected lower-grade deep mineralization
18m of 0.55% Cu from 736m
28m of 0.72% Cu and 5.9gpt Ag from 840m
Sergio Rivera, VP Exploration of Marimaca Copper, commented:
"Pampa Medina continues to demonstrate remarkable consistency of grade and thicknesses across the currently defined area of interest. The Phase II program was predominantly 300m-spaced grid-based drilling intended to define the extent of the mineralized system in which we are yet to define the limits. The 2026 program will focus on definition drilling of the identified high-grade corridors between sections N7,441,100 and N7,440,500, as well as Pampa Medina Norte (SMD/SMR-01) in both oxides and sulphides, as well as continued large-scale step-outs to test regional continuity of the favourable host rocks. Our exploration model is strengthening at Pampa and we look forward to updating the market with our evolving interpretations of the manto-system ahead of the Phase III program in 2026.
Hayden Locke, CEO of Marimaca Copper, commented:
"Pampa Medina continues to extend significantly. Our area of interest, defined by drilling, now extends 3km by 2km, but geophysics suggests ongoing potential for extensions. The continuity of mineralization and exceptional grades we are encountering are not unusual for sediment hosted copper deposits, which are known to have a larger footprint compared to the more confined, but vertically extensive, porphyry deposits typical of this region."
"What is incredibly unusual, is the average true thickness of the mineralized sediments. Drilling shows the high-grade mineralization is generally present over a minimum true thickness of 20m to 30m and, in many cases, is well over 100m in true thickness. When compared to one of the most prolific copper belts on the planet - the Kupferschiefer in Poland and Germany - it is extraordinarily thick. The estimated mining horizon true thickness across Section N7440 800 at Pampa Medina is, on average, more than 10x thicker and, in some cases, more than 50x thicker than the Kupferschiefer deposits currently mined by KGHM. Pampa Medina exhibits similar copper grades and slightly lower average silver grades when compared to those Tier 1 operations, but over significantly larger mineable widths, which indicates efficient, bulk tonnage, mining methods may drive lower unit costs in an eventual operation."
"The silver content provides a valuable addition to the deposit and enhances our view of its potential. We note the highly accretive financings being undertaken around streaming silver and we expect, give the consistency of silver mineralization encountered in this batch of drilling, that it will provide an opportunity for the Company to monetize for the benefit of its shareholders in the future. We are assaying the rest of the drilling completed at Pampa Medina and will release the results to the market when received."
Overview of Pampa Medina
Pampa Medina is a manto-style copper deposit dominantly hosted in Jurassic-Triassic sedimentary units (sandstones, conglomerates, tuffs and black shales) overlain by andesitic volcanics and underlain by an Upper Paleozoic complex of metamorphosed sediments, volcanics and intrusions. Key lithological units are intruded by a dyke swarm and affected by post mineral normal faulting. Copper was originally identified in near-surface oxide mineralization dominated by atacamite, chrysocolla and both secondary chalcocite, and has now been identified in high-grade zones of bornite, chalcopyrite, covellite and chalcocite which extend at depth beyond the oxide-primary transition. Elevated silver grades are present in in both oxide and sulphide copper-mineralized zones and are generally correlated with copper grade.
Following Marimaca's consolidation of the project area and surrounding land packages in 2024, the Company reinterpreted all available geological information and developed an updated geological model for Pampa Medina, which identified the lower sedimentary units of interbedded sandstones, shales, tuffs and conglomerates as the priority target horizons for future drilling. Marimaca's 2026 drilling campaign will focus on three priority goals: definition of the high-grade sulphide-dominant central corridor, infill of the identified oxide extensions, and further step-out drilling to test potential extensions of the broader system identified in geophysical work completed to date.

Figure 1: Regional Map - Marimaca, Pampa Medina and Regional Infrastructure

Figure 2 - Pampa Medina Deposit and Step-out Drilling Locations

Figure 3 - Cross Section Looking North - Pampa Medina 7,440,800 N

Figure 4 - Cross Section Looking North - Pampa Medina 7,440,500 N
Hole | Total Depth (m) |
| From (m) | To (m) | Intersection | % CuT | gpt Ag |
SWRD-01 | 956 |
| 694 | 732 | 38 | 1.43 | 11.8 |
Including | 694 | 702 | 8 | 2.11 | 15.5 | ||
And | 718 | 732 | 14 | 1.86 | 19.3 | ||
| 848 | 868 | 20 | 0.84 | 3.0 | ||
SWRD-02 | 944 |
| 520 | 594 | 74 | 1.21 | 7.9 |
Including | 520 | 568 | 48 | 1.62 | 11.5 | ||
Including | 532 | 544 | 12 | 2.07 | 17.2 | ||
| 814 | 842 | 28 | 0.52 | - | ||
SWRD-03 | 956 |
| 736 | 754 | 18 | 0.55 | - |
| 822 | 880 | 58 | 0.49 | 3.3 | ||
Including | 840 | 868 | 28 | 0.72 | 5.9 | ||
SWRD-04 | 898 |
| 322 | 380 | 58 | 0.49 | - |
Including | 332 | 348 | 16 | 1.00 | 5.9 | ||
Including | 338 | 342 | 4 | 2.51 | 14.5 | ||
And | 368 | 376 | 8 | 1.17 | 5.0 | ||
| 660 | 670 | 10 | 0.71 | 6.4 | ||
| 706 | 710 | 4 | 1.06 | 8.5 | ||
| 820 | 824 | 4 | 1.08 | 17.0 | ||
| 836 | 842 | 6 | 0.85 | 9.7 | ||
SMRD-34 | 950 |
| 148 | 194 | 46 | 0.90 | 10.8 |
Including | 158 | 194 | 36 | 1.08 | 13.8 | ||
Including | 166 | 172 | 6 | 3.01 | 37.3 | ||
| 600 | 710 | 110 | 0.57 | 3.9 | ||
Including | 600 | 624 | 24 | 1.37 | 12.2 | ||
Including | 606 | 616 | 10 | 2.58 | 25.8 | ||
And | 684 | 694 | 10 | 0.92 | 5.8 |
Table 1: Table of Intersections
Hole ID | Type | Easting | Northing | Elevation | Azimuth | Dip | Depth |
SWRD-01 | RCD | 406194.26 | 7440803.69 | 1288.92 | 270 | -55 | 955.6 |
SWRD-02 | RCD | 406198.93 | 7440504.24 | 1287 | 270 | -55 | 944 |
SWRD-03 | RCD | 405899.9 | 7440801.41 | 1296.05 | 270 | -55 | 956 |
SWRD-04 | RCD | 405900.19 | 7440502.19 | 1293.18 | 270 | -55 | 898 |
SMRD-34 | RCD | 406399.17 | 7440496.46 | 1282.63 | 270 | -55 | 950 |
Table 2: Drill Collars
Sampling and Assay Protocols
True widths are estimated as 80-90% of reported intervals, based on down-hole bedding and structural measurements. DDH holes were sampled on a 2m continuous basis, halved by a conventional core splitter on site with one half sent to the Andes Analytical Assay preparation laboratory in Copiapó and the pulps then sent to the same company laboratory in Santiago for assaying. Samples were prepared using the following standard protocol: drying; crushing all sample to -1/4" and passing through a secondary crusher to better than 80% passing -10#; homogenizing; splitting; pulverizing a 400-600g subsample to 95% passing -150#; and a 125g split of this sent for assaying. All samples were assayed for sequential copper %CuT (total copper); %CuS (acid soluble copper), %CuCN (cyanide soluble copper) and CuRes (residual copper), In addition to copper analyses, multi-element analysis including silver (Ag) was undertaken using ICP (multi-element Optical Inductively Coupled Plasma). A full QA/QC program, involving insertion of appropriate blanks, standards and duplicates was employed with acceptable results. Pulps and sample rejects are stored by Marimaca Copper for future reference.
Qualified Person / Competent Person
The technical information in this news release, including the information that relates to geology, drilling and mineralization was prepared under the supervision of, or has been reviewed by Sergio Rivera, Vice President of Exploration, Marimaca Copper Corp, a geologist with more than 40 years of experience and a member of the Colegio de Geólogos de Chile and of the Institute of Mining Engineers of Chile, and who is the Qualified Person for the purposes of NI 43-101 responsible for the design and execution of the drilling program.
The information in this announcement which relates to exploration results for the Pampa Medina Project is based on, and fairly reflects, information and supporting documentation prepared by Sergio Rivera, VP Exploration of Marimaca, a Competent Person who is a member of the Comision Minera (Chilean Mining Commission), Colegio de Geólogos de Chile and of the Institute of Mining Engineers of Chile. Mr. Rivera has sufficient experience that is relevant to the style of mineralisation and types of deposit under consideration and to the activity being undertaken to qualify as a Competent Person as defined in the 2012 Edition of the Joint Ore Reserves Committee Australasian Code for Reporting of Exploration Results, Mineral Resources and Ore Reserves. Mr. Rivera consents to the inclusion in this announcement of the matters based on his information in the form and context in which it appears.
Contact Information
For further information please visit www.marimaca.com or contact:
Tavistock
+44 (0) 207 920 3150
Emily Moss
marimaca@tavistock.co.uk
Forward Looking Statements
This news release includes certain "forward-looking statements" under (without limitation) applicable Canadian securities legislation, including, without limitation, statements regarding the development of activities at Pampa Medina, the potential growth of Pampa Medina, and the discovery's potential to complement the MOD. There can be no assurance that such statements will prove to be accurate, and actual results and future events could differ materially from those anticipated in such statements. Forward-looking statements reflect the beliefs, opinions and projections on the date the statements are made and are based upon a number of assumptions and estimates that, while considered reasonable by Marimaca Copper, are inherently subject to significant business, economic, competitive, political and social uncertainties and contingencies. Many factors, both known and unknown, could cause actual results, performance or achievements to be materially different from the results, performance or achievements that are or may be expressed or implied by such forward-looking statements and the parties have made assumptions and estimates based on or related to many of these factors. Such factors include, without limitation: risks that the development activities at Pampa Medina will not progress as anticipated, or at all, risks related to share price and market conditions, the inherent risks involved in the mining, exploration and development of mineral properties, the uncertainties involved in interpreting drilling results and other geological data, fluctuating metal prices, the possibility of project delays or cost overruns or unanticipated excessive operating costs and expenses, uncertainties related to the necessity of financing, uncertainties relating to regulatory procedure and timing for permitting submissions and reviews, the availability of and costs of financing needed in the future as well as those factors disclosed in the annual information form of the Company dated March 27, 2025 and other filings made by the Company with the Canadian securities regulatory authorities (which may be viewed at www.sedar.com). Readers should not place undue reliance on forward-looking statements. Marimaca Copper undertakes no obligation to update publicly or otherwise revise any forward-looking statements contained herein whether as a result of new information or future events or otherwise, except as may be required by law.
None of the TSX, ASX or the Canadian Investment Regulatory Organization accepts responsibility for the adequacy or accuracy of this release.
This announcement was authorised for release to the ASX by the Board of Directors of the Company.
Appendix 1 - JORC Code 2012 Table 1 (ASX Listing Rule 5.7.1)
Section 1 Sampling Techniques and Data
Criteria | JORC Code explanation | Commentary |
|---|---|---|
Sampling techniques |
| All current drilling conducted at Sierra Medina, which includes the Pampa Medina deposit, was completed under the supervision of a registered professional geologist as a Competent Person/Qualified Person (QP) who is responsible and accountable for the planning, execution, and supervision of all exploration activity as well as the implementation of quality assurance programs and reporting.
|
Drilling techniques |
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Drill sample recovery |
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Logging |
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Sub-sampling techniques and sample preparation |
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Quality of assay data and laboratory tests |
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Verification of sampling and assaying |
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Location of data points |
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Data spacing and distribution |
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Orientation of data in relation to geological structure |
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Sample security |
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Audits or reviews |
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Section 2: Reporting of Exploration Results
Criteria | JORC Code explanation | Commentary |
|---|---|---|
Mineral tenement and land tenure status |
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Exploration done by other parties |
| 1. Pampa Medina Concessions
2. Madrugador Concessions
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Geology |
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Drill hole Information |
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Data aggregation methods |
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Relationship between mineralisation widths and intercept lengths |
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Diagrams |
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Balanced reporting |
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Other substantive exploration data |
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Further work |
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SOURCE: Marimaca Copper Corp.
View the original press release on ACCESS Newswire:
https://www.accessnewswire.com/newsroom/en/metals-and-mining/marimaca-reports-further-high-grade-copper-and-silver-intersections-more-than-600-1146219



