engleski

Pillow lavas of Hruškovec, North Croatia, Rifting Magmatism or dismembered ophiolitic sequence

The presented research deals with variety of volcanic facies of the large extrusive igneous body, long a few km, thick several hundred meter. Although tectonically dismembered and implaced into Cretaceous melange formation, it consists of several facial units: 1. Facies of coherrent pillow lavas. Pillows from several meter to dm size, with radial columnar joints. Concentric joints occur in the pillows approximately parallel to the flow direction. Tortoise shell joints and centrally placed cavities filled with secondary minerals are common within 2. Facies of "Closely packed pillows". They vary in size from dm to half-meter, usually showing sign of implacement accomodation, with clear younging direction. The sideromelane shards and spalls are cemented by secondary minerals (calcite, quartz, epidote, chlorite and pumpellyite). 3. Facies of "in situ hyaloclastite" can be subdevided into subfacies of 3.1."Isolated pillow breccia" 3.2. "Pillow fragment breccia" and 3.3. "Peperitic hyaloclastites".

Pillow lava; rifting; ophiolites; North Croatia

nije evidentirano