Erika Epithermal Au-Ag Project, Guerrero, Mexico
Available for option
 Location & Access
The Erika property consists of two contiguous claims covering approximately 16,000 hectares, located in Guerrero State, Mexico.
The property is accessed by road via Federal Highway 95, which crosses the eastern boundary of the claims. Acapulco is 150 km south and Iguala is 47 km north of Erika.
The claims are centred on the village of Coacoyula de Alvarez (pop. 3,100) and numerous small roads and trails provide access throughout the property.
The Mezcala gold skarn district is located approximately 15 km to the south of Coacoyula and hosts more than 10 million ounces of gold in eight major camps. The principal gold skarn deposits are: El Limon/Guajes, Bermejal, Los Filos and Nukay.
The Taxco epithermal Ag-Au deposit located approximately 45 km to the north produced over 30 million tonnes of ore.
Geology
The Erika Property lies on the Guerrero-Morelos Platform, which consists of over 2,000 m of Mesozoic carbonate rocks unconformably overlaying Early Cretaceous to Late Jurassic island arc sequences of Guerrero Terrane. The Guerrero-Morelos Platform is bounded to the south by the Xolapa metamorphic core complex, and to the north it is covered by Trans-Mexican Volcanic Belt magmatic rocks.
On the property, Massive and fossiliferous, to locally silty banded limestone of the Cretaceous Morelos Formation are overlain by interbedded sandstones, siltstones, and mudstones of the Mezcala Formation.
The Mesozoic sedimentary sequence strikes generally to the north, and is overlain by a thin package of Tertiary felsic volcanic rocks. The felsic volcanic unit consists of brecciated volcaniclastics containing fine-grained, angular to sub-rounded lithic fragments, quartz phenocrysts, with rare pumice fragments. 
Silicification, argillic alteration, and dolomitization are the main styles of hydrothermal alteration on the Erika Property and is interpreted to be representative of steam heated alteration and replacement silicification typical of a paleo water table environment representing the top or old surface of the once active hydrothermal system.
The property includes several areas of intense clay-sulphate alteration, from which clay has been mined for industrial applications, including ceramics. Small-scale mining for mercury is recorded to have taken place in the 1940’s at Erika with up to 20 kg per week being produced from the richest mine.
Past Work
Subsequent to identifying the property, Almaden carried out induced polarization (IP) and Natural Source Audio-Frequency Magneto-Teluric (NSAMT) geophysical surveys over areas where prospecting, alteration mapping and soil geochemical surveys outlined mineralisation and alteration.
A limited 7 hole drill program was conducted in 1997 but targeted IP geophysical anomalies. Up to 1 g/t gold was returned from this drill program however later interpretation suggests that the subsequent NSAMT survey and more comprehensive soil surveys (conducted in 2006) were more successful in identifying the targets of interest than the earlier IP work. These targets have not yet been drilled.
NSAMT surveys, which have identified possible feeder structures on the project characterised by resistivity and conductivity highs, was a key methodology, successfully identified mineralised structures that were subsequently drilled beneath a similar zone of alteration at the Juanicipio deposit (MAG Silver Corp.).
More than $250,000 was spent on geochemical soil surveys at Erika in 2006, with sample spacings of 200 m x 50 m over the western portion of the claims. While a small number of strongly anomalous gold and silver assays were noted, the mercury, arsenic and antimony signature is the primary feature of interest on this property and is thought representative of the surface expression of the deep feeder structures targeted.
Summary and Recommendations
The 100% owned Erika project covers a shallowly eroded epithermal gold-silver system in southern Mexico. Management believes that the alteration and mineralisation, including steam heated acid sulphate alteration, mercury mineralisation and replacement silicification developed in volcanic rocks overlying carbonate rocks, are all indicative of what can be expected to occur over high grade silver-gold vein systems such as the nearby Taxco vein system which has produced over 1 billion ounces of silver.
Almaden Minerals Ltd. (which vended the project to Tarsis in 2007) completed geochemical rock and soil sampling and NSAMT geophysics which have defined several drill targets interpreted to reflect structural feeder zones beneath the high level alteration exposed with the potential to host high grade silver-gold mineralisation. A drill program to test these exciting targets has been recommended. 
Downloads
Erika Technical Brochure
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