بررسي وضعيت ساختاري ناحيه معدني هيرد (جنوب بيرجند) با استفاده از تفسير داده هاي مغناطيس هوايي، ماهواره اي و مشاهدات صحرايي و ارتباط آن با كانه زايي طلا

Structural Analysis of Hired Mining Area and its Relation with Gold Mineralization using Aeromagnetic Data, Satellite Images and Field Studies, South of Birjand, Iran

Hired area is located in the northeastern border of Lut zone and western vicinity of Sistan suture zone. Northern part of Sistan suture zone trending NW-SE with complicated structure is the locality of several considerable ore deposits. We have employed aeromagnetic data, satellite images and field observations to consider the relation of surface and subsurface structures to the significant superficial structural features of Hired mining area. Aeromagnetic data were processed by applying appropriate filters including Reduction to pole and First vertical derivative for proper distinguishing the magnetic features. In addition, high pass filters were used for edge sharpening of the ASTER images. Aeromagnetic data have shown two main N-S and NW-SE structural directions which follow the northern Sistan suture zone. Presence of mineralized and altered veins and brittle shear zones with the same trend around the fractures is noticeable. Moreover, fractures intersections and conjuncture places are dramatically compatible with mineralization areas. Another result from aeromagnetic data is identification of a circular structure in the east of study area. The gold mineralization has occurred in the west part of mentioned structure which is strongly affected by NNW striking features. Satellite images in addition to confirmation of aforesaid structural trends imply a third structural NE-SW strike. This structure is not vivid on the aeromagnetic map and has only an ambiguous trace on it. Our field measurements verify this new structural trend as well.