The ore zone is strongly recrystallised and massive, comprising phlogopite-chlorite-tremolite-talc schist, amphibolite
with lenticular quartzo-feldspathic layering and quartz-muscovite-biotite-sillimanite schist.
These rock units from north to south include the mafic-ultramafic Jijal complex, the Kamila amphibolite
, the gabbronorite-dominated Chilas complex, the predominantly granitic Kohistan batholith, Chalt and associated volcanics and Yasin group metasediments (Fig.
The Luusika Bouguer anomaly source is placed within the Alutaguse domain, which is characterized by amphibolite
facies rocks that pass towards granulite facies rocks (Bogdanova et al.
Three main geological units lie in the area of El Vapor district, (Fig 1): (i) San Lucas quartz-feldspathic gneisses (Gonzalez, 2001), which contains lenses of amphibolite
and marble and are Proterozoic (Feininger et al., 1972); (ii) Segovia batholith of Jurassic age (160 [+ or -] 7 M.a., K/Ar in hornblende, Feininger et al., 1972), consists of a diorite with textural and compositional variations of quartz diorite and locally hornblende gabbro; and finally, (iii) Segovia sedimentary rocks in the west of Segovia mainly composed of black shales interbedded with siltstones, sandstones and intraformational conglomerates, which in the north of the area have been dated between the upper Aptian and the lower Albian (Feininger et al., 1972) based on macro-fauna dating.
PHYSICAL PROPERTIES OF GNEISS, SCHIST AND AMPHIBOLITE
Weight Modulus of Shear modulus Names of rocks (kg/[m.sup.3]) volume (MPa) (MPa) Chlorite 2560 70 41 amphibolite
Friction Cohesion angle Tensile Names of rocks (Pa) ([degrees]) strength (Pa) Chlorite 900 21 0 amphibolite
Bai, "Research on dynamic mechanical performance of amphibolite
under cyclical impact loading at different confining pressures," Journal of Vibration and Shock, vol.
7), presence of all the polished stone tools found in the rock-shelter --two amphibolite
flakes from arbitrary spit 1, square d6, resulting from the reshaping of axes or adzes--, and an ochre nodule found in spit 2 in square c6, related to indeterminate uses --personal ornamentation?
ROCKS OF SPITSBERGEN Carbonate rock 5 536,36 [km.sup.3] Sandstone & Psammite 4 211,46 [km.sup.3] Mudstone & Shale 1 945,44 [km.sup.3] Siltstone 1 232,27 [km.sup.3] Conglomerate & Breccia 660,73 [km.sup.3] Evaporite 134,45 [km.sup.3] Metaigneous rock 727,31 [km.sup.3] Quartzite 699,39 [km.sup.3] Metasediment 593,22 [km.sup.3] Schist 584,03 [km.sup.3] Marble 413,18 [km.sup.3] Amphibolite
346,41 [km.sup.3] Gneiss 270,03 [km.sup.3] Granite 521,18 [km.sup.3] Plutonite 117,06 [km.sup.3] Vulcanite 25,19 [km.sup.3] Unknown 534,65 [km.sup.3] Total 18 552,36 [km.sup.3]
However, the remaining rocks in the formation in that area could not be readily assigned to any of the other members of White and Boehner (2008) and hence two additional members were identified: member ps, mainly pelitic schist interbedded with subordinate metacarbonate rocks, amphibolite
, and quartzite and member qf, quartzofeldspathic schist with quartzite, metaconglomerate, and minor amphibolite