THE STRUCTURAL AND TEXTURAL CHARACTERISTICS OF ROCKS

Code: sample name - rock type - attributes: origin
    Sedimentary rocks
851, 852 - conglomerate - facetted, smooth, polished and varnished pebbles; red oxidised clay matrix: perhaps a desert wadi deposit, clay of loess origin. Photo descong.jpg  Photo descong3.jpg
153 - conglomerate -  rounded, spherical, polymictic clasts; perhaps a beach lag deposit. Photo conglom.jpg
DL/71/13 - sandstone - clastic, red, rippled; slickensided fault surface: fluvial/lacustrine. Photo redsand.jpg
1-6a2 - biogenic limestone - Halycites chain coral; Favosites hexagonal honeycomb coral; stromatoporoids; crinoid allochems; bioturbated; framestone: coral reef. Photo chaincoral.jpg
1-1f1 - siltstone - varves, dropstone: glacial marine. Photo dropstone1.jpg   Photo dropstone2.jpg
GP23 - limestone - finely laminated and bedded, slump folding, bedding truncates the folds: neritic or distal turbidite.
Photo slump.jpg

    Igneous rocks
2-4-1-b - chromitite - graded bedding, crystals of chromite in a serpentine matrix: ultramafic cumulate.
 Photo chromite.jpg
2-8a - diabase - chilled margin of diabase against diabase: hyperbyssal intrusive. Photo diabase2.jpg
2-9b - pillow lava - variolitic texture: extrusive mafic volcanic rock. Photo pillow.jpg
3-4b - obsidian - glassy looking, conchoidal fractures: extrusive felsic volcanic rock. Photo obsidian1.jpg  Photo obsidian2.jpg  Photo obsidian3.jpg
1-2-2a - basalt - ‘daisy stone’, glomeroporphyritic, zoned feldspar, green pumpellyite; brown oxidised matrix: extrusive mafic. Photo daisystone.jpg
6-13 - alkali granite - megacrystic, rapakivi texture of oligoclase rims around K-feldspar megacrysts; biotitic matrix: intrusive granitoid. Photo rapakivi.jpg
A - granite - grain size variation of granite to pegmatite: intrusive. Photo granite.jpg
B - basalt - plagioclase megacrysts: intrusive dike. Photo plag-phyric diabase.jpg

    Metamorphic rocks
4-11 - psammite (meta-arenite) - coarse grained, bedding, folding; bright green specks of fuchsite after detrital chromite: tectonite. Photo cr-sstne.jpg
5-4a - pelite (metasiltstone/argillite) - bedded, meta-siltstone, meta-clay/mudstone; folding, cleavage, lineation: s-tectonite. Photo cleaved argillite.jpg
5-2-1 - laminated argillite - bedding, cleavage lineation; high angle bedding\cleavage relationship: s-tectonite.
Photo bedding on cleavage surface.jpg  Photo bedding and cleavage surfaces.jpg   Photo lineated bedding surface, argillite.jpg
5-12a - mylonitic gneiss - lineated, polygonized; porphyroclasts: l-tectonite Photo lineated gneiss surface 1.jpg   Photo lineated gneiss surface 2.jpg    Photo lineated gneiss surface 3.jpg
5-2-a - schist - foliated; bedding, albite porphyroblasts, high angle between foliation and bedding: s-tectonite. Photo schist.jpg
C1, C2 - amphibolite - acicular amphibole and porphyroblasts of orthopyroxene (bronzite). Photo opx amphibolite.jpg
D - migmatite - granoblastic, relect pyroxenite, amphibole, magnetite, sulphides: mafic migmatite. Photo migmatite.jpg
C25 - sandstone - shatter cones: impact. Photo shattercones.jpg
E1, E2 - breccia - fluidal, embayed, sutured contacts of some clasts; rims; carbon: impactite. Photo Onaping fall fall material.jpg   Photo Onaping fall fall material.jpg