Figure 1. Location map of La Morena project, northern Coahuila State, approximately 250km east of Chihuahua, and 40km northeast of the Hercules Mine (iron skarn). Although not shown at this scale, several large electrical transmission lines cross the property. Click map to enlarge.
Figure 2. Concession map of La Morena project. Click map to enlarge.
Figure 3. Schematic model showing the mineralization style and targets at the La Morena Property.
Figure 4. Colour satellite image showing altered limestone zone and major NW trending structure at La Morena. Click map to enlarge.
Figure 5. La Morena stratigraphic column and mineralization. Mineralization is hosted in a series of Lower Cretaceous limestones, with best targets being the Cupido and La Pena, which host many CRD deposits in Northern Mexico. Click map to enlarge.
Figure 6. Compilation of previous drilling in the central area of the Diana Grid, near Mina Campo. Click map to enlarge.
Figure 7. Compilation of previous drilling in the northeast area of the Diana Grid, near Mina La Diana. Click map to enlarge.
Figure 8. Compilation of the Refugio grid on Cu in soils, showing various structural elements, old mine workings, and IP target (preliminary). Note that both the antiform axes trend toward the area of chargeability, and toward the area of highest Zn-Pb-Ag in soils. Click map to enlarge.
Figure 9. Compilation of the Diana grid on Cu in soils, showing various structural elements, old mine workings, and IP target. Note that none of the previous holes tested the target. Click map to enlarge.
Figure 10. Inverted pseudosection model of the Diana grid IP target (chargeability and resistivity) on L1700N, where the target is closest to surface. Note that LM-4 returned a significant Ag-rich zone just above the target, but bottomed in La Pena shales, indicating the chargeability likely originates in the older Cupido Formation, host to several CRDs in northern Mexico. Click map to enlarge.
Figure 11. Plan of inverted chargeability at 350m depth below surface. L1700N is highlighted in purple. Note possible satellite targets on the west edge of the grid. Click map to enlarge.
- Early stage copper, silver, gold property
- Over 2700 hectares
- 100% Stockport Exploration ownership
- Silver intercepts up to 1245 g/t
- Surface grab samples up to 1750 g/t
Location, Description & Tenure
The La Morena Property is a Carbonate Replacement Deposit (CRD) and Skarn prospect located in the State of Coahuila, 150 kilometres south of the Texas border. The La Morena Property is accessible by gravel road from the towns of El Alicante or Lopez Mateos and consists of one exploitation concession, and two exploration concessions:
|La Morena Dos
In May 2004, Linear Gold Mexico purchased the La Morena concession outright from the previous owner for a one-time cash payment of US$120,000 with no retained royalty. The El Refugio concession was staked during 2005 by Linear Gold Mexico, after work in the area suggested additional mineralization on adjacent open lands. In 2010, the La Morena Dos concession was staked by Stockport Exploration (formerly Linear Metals) to augment the Company's land position over this prospective area.
Stockport Exploration Mexico acquired a 100% interest in the La Morena Property from Linear Gold Mexico in March 2006 for US$555,000. The property is not subject to any royalties.
Geology and Mineralizaton
The property is located in the central portion of the Sierra La Morena mountain range and encloses the La Morena mineral prospects, located in a pronounced, near-circular topographic depression about 8.5 square kilometres in area.
The topographic low is coincident with hydrothermally altered, recrystallized limestones and a 1X2 kilometre zone of NE trending veins, mantos and moderate to strong stockwork quartz-carbonate veining and brecciation. The principle alteration mineral assemblage is silica + carbonate + sericite + pyrite. Mineralization is dominated by oxides above 100 metres depth, below which primary sulfide mineralization occurs as pyrite, pyrrhotite, chalcopyrite, tetrahedrite, and polybasite.
The topographic low and coincident alteration zone is believed to be associated with a buried intrusion. The intrusion is estimated to be 600-700 metres below the surface and represents a potential Copper-Gold porphyry target. This porphyry system is believed to be the driving mechanism for the observed mineralization at surface and in drill intersections. Mantos and chimney style mineralization are the targets for near surface exploration.
Previous Drill Programs - Diana Area
In the late 1970's a CRM/MMAJ co-operative completed 16 diamond drillholes (includes 6 shallow Winkie holes). In 2005 and 2006 Stockport completed an additional 10 diamond drill holes. All holes (1970's and 2000's) were generally targeting known surface mineralization and its presumed subsurface extension in the area of what is now the Diana Grid (circular topographic depression with strongly altered limestones). Most of this drilling is clusterd in the central part of the grid around Mina Campo, or in the NE part of the grid around Mina La Diana.
Both drill programs were successful in identifying silver-bearing copper mineralization (see drill highlights table), with the most significant intersection observed in hole LM-04 wherein a 3 metre interval returned 1245 g/tonne silver. Also, hole LM-10 provided a very significant result intersecting 26.7 metres of 114.5 grams per tonne silver and 0.9% copper (unfortunately only 20% of the core was recovered). At the time, Stockport was focussed on its Cobre Grande project, and additional work at La Morena was put on hold.
Table 1: La Morena Drill Highlights
New Surface Discoveries - Refugio Area
In 2006, Stockport geologists also confirmed the presence of significant zones of alteration and mineralization approximately 2 km metres north of the centre of the topographic depression, associated with several artisanal workings, both known and unknown. Nine out of 25 grab samples returned over 1000 g/tonne silver with a high of 1,750 g/tonne (56 troy ounces). Four samples returned greater than 10% lead, greater than 3% zinc (high of 30%), and greater than 0.1% copper. The discovery of this area, well north of the drilled area, confirmed the significant exploration potential of this property.
see press release of October 26th, 2010). The large number of workings and showings (now more than 20) in the Refugio grid area suggest a strong and possibly extensive near-surface manto system that is largely covered by colluvium and talus deposits. Mineralization is controlled by faults and antiform fold hinges.
To guide further subsurface exploration of the large alteration system (approximately 2 km x 4 km), Stockport contracted SJ Geophysics (Vancouver) to complete a large, moderately deeply penetrating IP survey over most of the altered area, on both the Diana and Refugio grids, in the late summer of 2010. The grids are separated by a rugged, NW-trending, relatively inaccessible fault scarp that appears to be one of the major controlling structures on the mineralizing system. Several anomalous zones of chargeability and resistivity were delineated on both grids at various depths.
The technical information on this website was prepared under the supervision of Stockport Exploration's Vice President of Exploration, Matthew Rees, M.Sc., P. Geo., a qualified person as defined by National Instrument 43-101.