Environment                                                          Rock Type                                                                              Structure or Texture

 

A.          Subduction Zone -                                                 peridotite                                                                               often in discontinuous pods

deep burial over                                                   serpentine                                                                               and associated with rocks of

12 km                                                                      blueschist (glaucophane)                                                     ophiolite complex

 

B.            Subduction Zone                                                  thin marine sediments                                                         melange (heterogenous

pillow basalts                                                                          mixture):  ophiolite

basalts                                                                                     complex is crushed into

gabbro                                                                                     chaotic mass in and near

  subduction zone

 

C.            Ocean Floor -                                                       turbidites    ─┐                                                                      sequence kilometers thick

 formed at oceanic                                                pillow basalts │  ophiolite                                                    with sheeted

  rise                                                                        basalts        │   complex                                                         (interconnected) dikes

gabbro        ─┘

 

D.            Island-Arc Volcanoes -                                       andesite                                                                                 strato (composite) volcanoes

 formed from partial                                              diorite

  melt of descending                                            welded tuff

  sea floor                                                               ash

rhyolite

graywacke ss

 

E.             Continental Shelf                                                limestone                                                                               mineralogically mature

 (shallow water)                                                    shale                                                                                       well-sorted clastics             

  a.  black                                                                                stagnant - oxygen poor

  b.  red, brown, yellow                                                          environment

circulating water -

  oxygen rich environment

 

F.             Shorelines                                                             sandstone                                                                             thin crossbeds - often fossiliferous

  containing shells

 

 

G.            Continental Slope                                                shale                                                                                       slump structures;

 and Abyss                                                             mudstones, siltstones                                                         graded beds (turbidites);

sandstones                                                                           chemically mature

texturally immature

 

H.            Continental Deposits                                          conglomerates                                                                      stream, alluvial fans

arkosic sandstone                                                                high relief, active coastal

  margins

 

I.              Fold Mountain Systems                                      granite                                                                                    ore deposits

metamorphic rock                                                                 thrust faulting

(slate, phyllite, schist                                                          deformed rock units;

 gneiss)                                                                                    overturned beds

anticlines and synclines

 

 

 

 

 

 

 

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