General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Cross-bedded sandstone. Note the type of cross-bedding can rarely be determined in core.

Depositional Environment Represented:

    Foreshore environment where cross-bedding forms from migration of dunes and sandwaves.

Other environments where rock type is typically found:

    Any moderate to high energy environment in which migrating bed forms occur (channels, aeolian dunes, shallow marine).

General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Bioturbated sandstone. Burrows are similar to Paleophycus.

Depositional Environment Represented:

    Shoreface - moderate energy environment. The presence of alternating laminae of mud and sand indicate periods of low and high energy deposition.

Other environments where rock type is typically found:

    Not found in other environments

General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Horizontal bedded and bioturbated sandstone. Burrows are similar to Paleophycus

Depositional Environment Represented:

    Shoreface - moderate energy environment. Presence of laminae of mudstone indicate periods of low energy

Other environments where rock type is typically found:

    Any moderate energy environment but with burrows is typical of lower foreshore to shallow offshore facies.

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Parallel-to-burrowed sandstone. Burrow are horizontal forms similar to Paleophycus

Depositional Environment Represented:

    Shoreface. The alternation of parallel bedded sandstone in which burrows are rare to absent with densely burrowed zones suggests considerable variation in sedimentation rates, probably associated with storm/fairweather deposition.

Other environments where rock type is typically found:

    Not found in other environments

General Environmental Setting:

    Marine offshore to transitional zone

Rock Description:
    Fine grained sandstone and mudstone. Bioturbation and compaction. May locally contain gas-disrupted bedding.

Depositional Environment Represented:

    Shoreface to shallow offshore.

Other environments where rock type is typically found:

    Any moderate to low energy environment including lakes, lagoons and shallow marine environments.

General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Parallel bedded sandstone and mudstone (base). Because the mudstone and sandstone beds are parallel it is likely that the beds were close to horizontal at deposition. Thus the apparent dip of the beds in the core is a result of the beds not being drilled perpendicular

Depositional Environment Represented:

    Shallow offshore

Other environments where rock type is typically found:

    Not found in other environments

General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Convolute bedded and bioturbated sandstone and mudstone. Note the pyrite in the upper part of the core. The pyrite probably formed shortly after deposition (diagenetic) and indicates reducing (anoxic) conditions resulting from consumption of available oxygen by aerobic bacteria

Depositional Environment Represented:

    Lower shoreface to shallow offshore

Other environments where rock type is typically found:

    Not found in other environments

General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Alternating parallel bedded very fine grained sandstone and mudstone

Depositional Environment Represented:

    Lower most shoreface - offshore

Other environments where rock type is typically found:

    Any low energy environment such as a lake, lagoon, bay or offshore marine.

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Parallel bedded-rippled sandstone. Note horizontal burrow near bottom (probably Paleophycus)

Depositional Environment Represented:

    Upper shoreface/beach

Other environments where rock type is typically found:

    Paleophycus burrows only found in marine environments. Marine shoals, washovers, tidal deltas.

General Environmental Setting:

    Marine offshore transitional zone

Rock Description:
    Bioturbated very fine grained sandstone and mudstone Bioturbation has largely destroyed initial depositional environment

Depositional Environment Represented:

    Lower shoreface

Other environments where rock type is typically found:

    Predominance of fine sediment indicates low energy environment which together with burrows is characteristic of lagoonal, bay and offshore environments.

General Environmental Setting:

    Marine and transitional marine to tidal flat

Rock Description:
    Parallel bedded sandstone with large vertical to 'U' shaped burrows (probably Diplocrateron or Rhizocorallum). Parallel bedding defined by thin laminae of carbonaceous material and reddish brown siderite pellets

Depositional Environment Represented:

    Marine shoal/shoreface.

Other environments where rock type is typically found:

    Not found in other environments

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Cross-bedded sandstone

Depositional Environment Represented:

    Upper shoreface or distributary channel

Other environments where rock type is typically found:

    Moderate to high current velocity areas such as marine shoals, fluvial and tidal point bars, channel bottoms, distributary mouth bars, tidal inlets, tidal deltas and shelf sand ridges.

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Clean sandstone with distinct parallel bedding. Burrows absent.

Depositional Environment Represented:

    Shoreface/beach

Other environments where rock type is typically found:

    Clean sand areas subject to high-velocity currents such as exposed embayment shoals, upper portions of tidal deltas, washovers, fluvial and tidal point bars, channel bottoms and distributary mouth bars.

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Parallel and cross-bedded sandstone

Depositional Environment Represented:

    Upper shoreface/beach

Other environments where rock type is typically found:

    Areas with moderate to high velocity currents such as marine shoals, upper portion of tidal deltas, washovers, fluvial and tidal point bars, channel bottoms, distributary mouth bars.

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Granular, well sorted conglomerate. Note the absence of any fine sandy matrix and good granular porosity. This rock would make an excellent petroleum reservoir.

Depositional Environment Represented:

    Gravel beach-shoreface

Other environments where rock type is typically found:

    Areas of moderate to high current velocity such as braided streams, offshore bars.

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Sandstone with abundant burrow structures destroying all primary physical sedimentary structures. Type of fossil is uncertain, possibly Chondrites or Macaronichnus segregatus

Depositional Environment Represented:

    In the Gates Formation this trace fossil was found only in sandstones deposited in very shallow marine (intertidal) settings such as beaches and bars in distributary channels.

Other environments where rock type is typically found:

    Not found in other environments

General Environmental Setting:

    Marine shoreface - beach

Rock Description:
    Bioturbated sandstone. Original rock-interbedded clean sandstone and mudstone.

Depositional Environment Represented:

    Foreshore to offshore

Other environments where rock type is typically found:

    Interbedded clean sandstone and shale typical of lower foreshore to offshore environments or tidal areas where periodic high current velocities occur. Vertical burrows typical of transitional marine environments where filter feeders are dominant.


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