• F: sloping layer in x-stratification
• B: bedding plane (flat).

• isotropic (flow in all directions) b/c weak unidirectional flow and strong oscillator flow
• curved laminations
• low angle lamina intersections
• sharp lower bounding surface
• wavlengths 0.5-2m
• just above storm weather wave base (SWWB)
• concave-up x-sets grade into convex-up x-sets and vice versa
• mid continental shelf

• coarser than HCS (f-mgrS instead of silt-fgrS)
• concave-up shallow scours (swales not hummocks)
• lower angle than HCS
• shallower depth, between SWWB and Fair Weather Wave Base (FWWB) in shallowing-up sequences

   

• channels (fluvial and tidal envrs)
• scour + fill structures (SS)

• tool marks (cast of an imprint made by object impacting a muddy bed, strike of flow direction)
• groove casts (tool marks in groups, laminar flow)
• flute casts (aka: scour marks. long-aspect-ratio scours dug into soft-seds that tell flow direction absolutely, turbulent flow)
• current crescents
• parting lineation (sand grains line up parallel to current)

Soft-sed Structures:

Gravitational / Seismic Instability

Soft-Sed Strucs:

OTHER

• rain imprints (controversial, subaerial, raindrops)
• halite casts (dissolutions of salt crystals leaves cubic cast, subaerial/very shallow)
• mud cracks (subaerial, mud drying/wetting, hexagonal in plan view, mud chip breccias can form)
• syneresis cracks (subaqueous, conventional description is they are clays that suddenly see fresh water and chemical change makes them crack)
• adhesion ripples (sticky consolidated muds have S/Si blown over, ripples too small to be marine)

Secondary Structures:

Early Burial and Diagenesis

• Neptunian Dykes/Sills (overpressured sand)
• concretions (cement earlier than whole-rock cement, very resistant, Dol/Sid/Ank/FeOx)
• sand crystals
• styolites

Secondary Structures:

Exposure

• tepees
• palaeokarst
• grike (exposed horizontally-bedded limestone begins erosion as water moves along joints which turn into grikes as the joints get deeper)

indicate activity of organisms without being a true body fossil. biogenic structures in 3 categories:

1. bioturbation structures
2. bioerosion structures
3. peupty poops (coprolites)

sets of trace fossils grouped together for specific enviros, moving from coast to abyss:

1. trypanites (rocky coasts and hardgrounds)
2. glossifungites (burrows in semi-consol seds: coast)
3. skolithos (soft-beach sands with vertical burrows, U-shaped or cylindrical, btwn coast and sublittoral)
4. cruziana (sublittoral zone [just below low tide, soft sands/muds], mixed horiz/vert/inclined burrows + diverse tracks)
5. zoophycos (offshore-slope envr, horiz to slightly inclined tunnels)
6. nereites (complex horiz tunnels in slope-abyssal muds)

• facies: suite of sed features (texture, composition, type of strat, structures, etc) that characterize a sed enviro in time and space.
• facies association: lump facies together into one depositional environment, like 'beach' or 'tidal'

1. High Magnesian Calcite (>4% Mg in place of Ca, unstable, converts to lo-Mg after burial)
2. Aragonite (metastable polymorph converts to lo-Mg in burial, precipitated by many organisms, preferred CaCO3 precipitate in modern ocean, orthorhombic)
3. Low Mg Calcite

1. calcite CaCO3
2. aragonite CaCO3
3. dolomite CaMg(CaCO3)2
4. siderite FeCO3
5. ankerite CaFe(CaCO3)2
6. magnesite MgCaCO3
7. rhodocrosite MnCO3

Sr and Mn, have similar ionic radii and valence

measure isotopes and reconstruct palaeo pH, date rocks, determine if Mg content of ocean is result of weathering or hydrothermal input.

mainly pH which is controlled by CO2. 

Ca + 2HCO3 <-> CaCO3 + CO2 + H2O

calcite and CO2 produced mole for mole. so remove CO2 and rxn proceeds left to right, increasing CaCO3.  

1. increasing T drives CO2 out of water (decrease solubility)
2. decreasing P (from wave agitation or upwelling) decreases solubility too.

abundance of Mg interferes with calcite precip.

aragonite is not affected, which is why it is preferred in modern ocean.

modern ocean is 6x supersaturated in calcite.

1. whitings (spontaneous precipitation of fgr calcite in surface ocean)
2. ooids (highly agitated, supersaturated seawater)
3. aragonite bushes (during extreme supersaturation like after snowball earth, Fe inhibits nucleation so they grow spiky bushes)

1. direct precipitation to form hard parts of body
2. photosynthetic uptake (equals calcite precip)
3. bacterial mediation (important source of carbo cement, forms crust of calcite as Ca leaving cell reacts with CO2 entering)
4. bacterial decay of org matter can trigger calcite precip.

calcite solubility decreases with depth. lysocline is where it starts to decrease most rapidly. carbonate compensation depth CCD is where it is gone. 

Affected by: P (as P ^ calc-conc decreases), T (as T decreases calc-conc ^), and remineralization (CO2 goes back in, acidity increases).

approx 5-6000m. deeper in mid-latitudes and in younger oceans (more CO2 in older oceans).

1. carbonate grains (Si size or larger)
2. microcrystallien calcite (micrite, carbo mud)
3. sparry calcite (cgr recrystallized calcite from burial episode)
4. microbial laminations

1. carbonate clasts (extra and intraclasts)
2. skeletal particles
3. ooids (high E enviro, radial aragonite needle layers and tangentially picked-up mud layers. sphere ones are pisoids. need super-saturation)
4. other coated grains (= oncoids. still need super-sat)
5. peloids (micrite-bearing grains w/o internal structure: poops, round muds..)
6. aggregate grains (grains cemented)

micrite is vfgr carbo mud, aragonite needles or matrix, quiet depositional enviros.

sparry is less opaque, cement, replaces micrite or grains.

1. coquina (mechanically sorted, abraded, grain-support, poorly-cemented, fossil debris)
2. chalk (soft, fine limestone made of shells)
3. marl (siliciclastic clay and calcium carbonate)

1. floatstone: matrix-support
2. rudstone: supported by >2mm portion

1. bafflestone: organisms act as baffles
2. bindstone: organisms encrust and bind
3. framestone: organisms build a rigid framework

1. trapping/binding of seds onto sticky microbial mats [high E]
2. direct carbo precipitation within mat [during growth, during chemical change of seawater, or during decay]

biostrome: laterally continuous bed of stromatolite.

bioherm: isolated mound

• tepee structure
• molar tooth structure (crumpled, vertically oriented, sparry cement, synsedimentary)
• karst
• grikes
• styolites

1. chlorides: halite (NaCl)
2. sulfates: gypsum and anhydrite (CaSO4 + 2H2O for gypsum)
3. carbonates: dolomite and calcite

15m of evaporite for 1000m sea water.

• at 50% evaporation CaCO3 forms = 0.4% by volume
• after another 20% gypsum forms = 3.6% volume
• dolomite may form after gypsum, as a veneer on top of it
• after 10% more halite forms = 78%
• Mg and K salts form after that = 18%

• more bicarbonate and Mg
• less sulfs and chlorides
• contain hydrated Na-carbos, Na-sulfs, and hydrated Mg-sulfates

• at >45C gypsum goes to anyhdrite, 38% volume loss
• DEEP: laminated gypsum
• SHALLOW: palmate gypsum crystals
• TIDAL: ovoid gypsum nodules/casts
• SABKHA: [ocean flat subject to periodic flooding] chickenwire texture. grows displacively. 

1. saline pan (salina): dip in land separated from ocean by a bank. layers of salt and gypsum casts.
2. sabkha: seepage from ocean creates nodular anhy/gyp, affected by evaporation
3. lagoon: deeper version of salina, contains interbedded dolomite and org-rich muds, with floating xtals and palmate crystals on bottom
4. dessicated/silled basin: deep ocean basin is cut off from larger ocean like mediterranean was 5.5Ma.

1. bulls eye: limestone around edge, gypsum, halite in middle.
2. tear drop: halite at far edge (bottom of tear shape), gypsum in same shape but covering more area (up farther in tear) because concentration increases away from input.

1. iron formations (>15% Fe)
2. BIF 
3. pyrite shales
4. Fe-Mn sea-floor nodules

1. Algoma: narrow lens-like bodies, associated with volcanics and greenstone belts
2. Superior: thick, extensive, continental shelf, paleoproterozoic

• microxtalline qtz: chert
• coarse qtz
• chalcedony (agate)
• opal

sharp shift to deeper water from a transgressive event. max flood is finest grain seds marking the peak of the transgressive event.

apatite: Ca5(PO4) + fluorapatite, etc. generally called collophane

relative anoxia and high organic productivity.

upwelling supplies phosphorus to organic matter which is at surface. it dies and is eventually consolidated as phosphate nodules which form phosphates during decay and diagenesis. 

crust floats on asthenosphere like ice cube in drink.

archimedes principle: mass of fluid floating in equilibrium is equal to mass of fluid it displaces.

to compare to spots in crust, make a column of same dimensions. mass of each column must be equal. 

1. crustal thinning (Extensional stretching)
2. mantle-lithospheric cooling (contraction)
3. tectonic loading (orogeny)
4. sed/volcanic loading
5. kithospheric underplating (weight from below causes sinking)
6. geodynamic flow (asthenospheric downflow pulls crust with it)

tectonics

eustatic sea level change

tectonics (uplift = seds)

climate.

depth below which density is same, laterally.

mantle upwelling occurs above comp depth, up to base of thinned crust. (isotherm deflects upward)

depth = square root of age.

-heat flow = thermal diffusivity x thermal gradient

1. small load, no flexure.
2. load increases. flexure begins and peripheral bulge forms, with slight trench between load and bulge.
3. load at max size. bulge at max size, migrating away from load. max trench.
4. erosional stage at which both mountain and bulge are eroded away. release of load causes trench to decrease too.

amount of subsidence, uplift of bulge, and location of bulge all depend on flexural rigidity of plate.

1. divergent
2. convergent
3. transform
4. intraplate

1. hanging wall flanks footwall (sits low on, creating high relief and therefore high sed accumulation rates)
2. long/narrow basins
3. bimodal volcanism
4. abrupt facies changes (steep slopes and rapid topo changes)
5. abundant cgr seds (alluvial fans)
6. wedge-shaped sed packages (asymmetrical from onlapping of seds onto footwall)
7. rotation and erosion of units
8. may form intersecting sub-basin network.

Describe internal drainage basin and differentiate it from axial-trough system. What are these examples of?

• alluvial fans come off hanging and foot walls.
• playa or lakes at edges of alluvial fans (in between HW and FW).

EX: death valley and east african rift.

Axial trough interacts with meandering rivers.

These are the two types of continental rifts.

contain interbedded basalts

dissected by mafic dykes

commonly link up to failed rifts (aulacogens)

lead to passive margins

• normal faulting stops
• rift-associated basins fill
• "structures drape" (what?)
• broad coastal plain builds out from margin (into sea?)
• sigmoidal shape of sequence as it builds
• flexural bulge in hinterland
• wedge expanding seaward

Mantle upwelling: causes uplift - erosion - and some extension. When mantle below thinned basin cools it causes sinking, creating a deep basin without necessarily forming faults.

Subduction-related: pull from a downgoing slab (like in west-central US) can pull down crust above it. 

• symmetric sag in x-section
• hundreds of kms wide
• sedimentation lasts for 100's of Ma.
• common on NA continent
• should be circular in map/plan view if fully developed

1. trench (at front of subduction, from loading of oceanic crust, filled by marine seds)
2. forearc basin (btwn trench and arc/mountains on transitional basement, caused by loading of overriding plate, high sed rates, filled w/ lithic wackestones)
3. retroarc foreland basin (other side of arc/mountains from subduction on overriding plate, associated with fold-and-thrust, assymetric. in cont-cont collision the peripheral foreland basin is on the downgoing continental plate.)
4. back-arc basin (crust on other side of arc/mountains undergoes extension that is frequently enough to form oceanic crust, great thickness of immature volcaniclastics)

small rift basins

steep fault-bound margins with closeby cgr seds

1. fluvial
2. aeolian
3. lacustrine

• at areas of steep change in slope (mountains to plane..)
• often downward of major fault scarps
• anywhere (subaerial) that you get intense rainfall can have fans
• convex up
• gravel-boulder deposits
• lobes and distributory channels fan out downslope
• downfan decrease in grain size, increase in sorting and decrease in bed-thickness
• wedge-shape geometry from mapping
• discontinuous units
• includes debris flow deposits

define:

1. bajadas
2. fan deltas
3. sheetflood flow
4. incised-channel flow

1. coalesced alluvial fans
2. alluvial fans that build into standing water body
3. rapid, broad, unconfined, shallow, sed-laden flow
4. channels incised into upper fan

high E = braided. cgr. higher relief.

lower E = meandering. f-mgr. little slope. 

• erosion on outside of bend (higher E zone)
• lateral sed accumulation
• sed transport occurs on inside of bend (lower E zone)
• point bars are at bank

1. point bar: at bank. lateral accretion surfaces. x-beds. overall fining up.
2. braid bars: mid-channel, in braided rivers, lateral accretion, downstream migration

lowland around river that are periodically covered in water/seds (usually muds).

1. natural levees occur when seds slosh over bank and deposit material at edge.
2. crevasse-splay when floods breach natural levees to make fining-up sequences
3. avulsion is abandonning of channels (like in creation of oxbows)

• mainly sands/gravels (bars) and muds (floodplain)
• mod-poor sorting
• compositionally immature
• fining upwards
• channel lag deposits (coarse residual material)
• trough x-beds, ripple marks
• dispersed unimodal paleocurrents
• staacked channel/bar deposits separated by mud
• sharp facies changes

1. alluvial fans 
2. ephemeral streams
3. ephemeral saline (playa) lakes [temporally variable]
4. deflation surfaces (seds blown away)
5. sand dune field
6. sand seas (ergs)

light veg combined w/ sporadic and intense rainfall leads to high erosion rates

flash floods

evaporite deposits in playas

only processes are saltation, traction, and suspension which sorts finer (suspended) particles from coarser (cannot be moved, up to saltation)

1. Loess (accumulation of dust)
2. deflation pavement (makes ventifacts, or rocks that show scars of sand-grain impacts from wind)
3. moderate-well sorted dunes and ripples. (ripples have wavelength under 2m, height under 10cm, no internal cross lams due to saltation, pin-stripe lam from cgr on crest and fgr in trough)(dunes form from stoss-accretion + lee-falls + lee-backflow, stacks of large-scale cross beds w/ reactivation surfaces from changing wind direction and interdune surfaces)

wind (dust, waves, currents)

rivers (plume, debris underflow, lake margin currents)

atmospheric heating (density differences  = stratification + overturn, freeze/melt)

rhythmic

alternating light and dark

seds of cold lake envrs

1. no tidal currents
2. sequence of evaporites, or lack thereof
3. association with continental environments

• precipitated sed types (evaporites that may differ from marine, phosphates, cherts, carbonates)
• chem affected by precip/evap (changing concentration)
• often anoxic bottom waters
• biological processes important

• deltas (dump seds onto passive margin, wide grain size, fluvial- tide- or wave-dominated)
• estuaries (drowned valleys that see fluvial and marine mixing)
• beaches (sensitive to sea level, economic importance, 
• strand plains (attached to shore, sand that has parallel or semiparallel [to shore] ridges. wave-dom envr)
• barrier islands (separated from main land by estuaries, marshes or lagoons. channels allow ocean water to move in)
• lagoons (low E, semirestricted from ocean
• tidal flats (low-relief coasts with large tidal range, plains with network of channels)

fluvial: sed discharge controls sed deposition.

distributary channels, interdistributary bays, jets of river water + seds into ocean

tide: large tidal range, funnel-shaped distributary channels, channel sand ridges perpendic to shore, distributary movement, tidal flats)

wave: redistributes seds parallel to shore. constricted/deflected mouth, distributary deposits reworked into bars/spits/beaches, delta front becomes series of shore-parallel ridges called strandlines)

• homopycnal: density = that of water.
  cgr, abrupt deposition, makes Y-shaped bifurcations, gilbert-type w/ steep foreset and sigmoidal topset.
• hyperpycnal: greater density than water. jet moves along seafloor, density currents, turbidites common.
• hypopycnal: less dense than water. buoyant plume, rapid deposition of cgr at mouth, fgr seds may flocculate later, large shallow delta-fronts 

subaerial

upper delta plain: above high tide, rivers, floodplane, fresh lakes

lower delta plain: intertidal, distributary system, tidal channels

subaqueous

delta front: up to 10m, cgr

prodelta slope: fgr

either fining-up (distributary channel to interdistrib bay) or coarsening up (vice versa)

• backshore high tide and up
• foreshore high tide to low tide
• shoreface low tide to FairWeatheWaveBase
• Shoaling Zone (waves affected by shallowing water, height increases and wavelength decreases), Breaking Zone (waves curl/break from height), Surf Zone (foamy stuff btwn break and shore)
• swash (waves that have broken run up shore) and backswash (they run back)
• longshore drift/transport (wind pushes waves at angle to shore and swash/backswash moves them downshore in that direction)
• rip currents oncoming waves drive water lateral to shore, eventually two opposing senses of this motion meet and flow back out to see along surface of water (usually toward sand bar channels)

1. building of longshore bar
2. progradation of beaches around offshore promontory
3. segmentation of spit parallel to coast
4. takeover of pre-holocene beach systems

• backshore: aeolian, dunes, washover deposits (ex: hurricane)
• foreshore: gently dipping parallel laminae, heavy mineral laminae, ripple/dunes migrate parallel to shore
• shoreface: muti-direction trough xbeds, trace fossils, planar lamination, oscillation ripples
• tide-related: trough/planar/bidirection/ripple/herrigbone cross-stratification, reactivation surfaces, tidal rhythmites

1. fjord (drowned glacial valley)
2. ria (drowned river valley)
3. bar-built (spit)
4. coastal plain (funnel-shape)
5. delta-front
6. tectonic (ria + lagoon)
7. blind (ephemeral bar)

wave:

barrier islands

sand only in outer estuary

low-E middle zone

mud depo and clay flocculation

stratified

tidal:

open to ocean

long sand bars w/ tidal channels

tidal flats and salt marshes

well-mixed

• tidal process affects hydrology and sed flow
• wind + evaporation
• tidal strength controls restriction
• anoxia/dysoxia
• seds from tidal channels and ocean spill-over

1. subtidal (sands) cut by channels w/ bidirectional flow, lateral accretion and tidal rhythmites
2. intertidal (sand + mud w/ lenticular bed, wavy bed, or flaser bed)
3. supratidal (flooded marshes and mud, periodically inundated, cracked mud, tepee structures in carbonates)
4. sabkha (arid supratidal zone containing evaporites)

between low tide and continental shelf, includes intracontinental shallow seas (epeiric).

• shallow (avg 130m)
• width 2-1500km
• sed deposition and bypass

1.Shelf (continental margin)

2.Shelf break (shelf margin)

3.Slope

4.Deep basin 

5.Continental rise

6.Abyssal plain

7.Deep-sea trenches

1. tidal currents (structures perpendic to shore)
2. wave action/swells + storms (increased depth affected, beach erosion, seaward transport)
3. wind
4. oceanic currents
5. density currents
6. wind-generated currents
7. nepheloid flow (storms re-pick-up fgr/suspended debris and move them off shore)
8. geostrophic currents (boundary currents) 

• major relict fault from rifting
• edge of a major delta
• seds draped over basement high
• carbonate bank or reef
• slope average of 4degrees
• incised by submarine canyons

1. slumps: direction of slump is with vergence of folds/faults, breccias, contain fold/detachment surfaces, mass-wasting, gravitational cgr
2. debris flows: intraclastic diamictites, gravitational cgr
3. turbidity currents: graded beds, cgr make bulbous and fgr make sheet-like lobes, rhythmites, channeled through canyons
4. grain flows
5. contour currents (flows along the side of slopes, rather than down.)

1. abyssal plain
2. deep sea trench
3. mid-ocean ridge

1. pelagic mud/ooze (from wind-blown dust, distal turbidity and sed plumes, planktonic tests of CaCO3 and SiO2 raining down from foraminifera/diatoms/coccoliths/radiolaria)
2. turbidity currents
3. tephra (volcanism, bentonite)
4. glacial-marine rain-out (dropstones, etc)
5. manganese nodules-crust (chemogenic)

tropical marine!

• warm water = carbonate saturated
• clear water (terrigenous seds block sunlight and inhibit nucleation of carbonate seds)

1. mostly produced biocchemically
2. grain-size doesnt reflect hydrology
3. production is in-situ
4. self-sustaining (carboante factory)
5. style of accumulation depends on origin of seds

protects from storms and waves by absorbing energy, creates a calm back-reef which may become depleted in oxygen.

rims are frequently reefs b/c corals like to grow at edge of shelf in warm areas.

1. rimmed
2. unrimmed
3. ramp
4. isolated platform
5. epeiric (shallow sea)

1. tidal flat (mud and sands, flaser/wavy/lenticular bedding, microbial laminates)
2. lagoon facies (marshes, fossils, low E)
3. shoal facies (cross-bedding, lime sand, fossils)
4. reef facies (boundstone)
5. slope facies (steep slope being broken by waves, huge talus, slumps)
6. basinal series (abyssal plain, thin laminations, fgr)

high E envrs (breaking waves)

shallow

rigid carbonate build-ups from: blue-green algae, foraminifera, bryozoa, sponges, molluscs, stromatolites, archaeocyathids, stromatoporoids

1. barrier (rim of platform)
2. fringing (hug coast line)
3. atolls
4. patch reefs (isolated systems on ramps)
5. pinnacle reefs (super tall column sticking out of water, formed during transgressions. talus around base.)

• frame-builders (coral, stromatolites..)
• sediment contributors (crinoids/algae)
• bafflers (sea grass)
• binders (cyanobacteria)
• precipitators (cyanobacteria)

1. valley
2. piedmont (alpine)
3. ice sheets (on land, huge,antarctica/greenland)
4. ice domes (ice sheet with a dome)
5. ice stream (very fast-moving piece of ice in an ice sheet)

define:

1. subglacial
2. supraglacial
3. ice-contact zone
4. englacial
5. proglacial
6. periglacial

1. plucking zone btwn glacier and ground, leaves flour.
2. upper surface of glacier
3. margin of glacier - morraines and ice-damned lakes
4. inside the glacier
5. downstream from glacier
6. influenced by same climate as glacier but not connected

• lateral (on the sides, along valley slope), terminal (at the end), medial (two glaciers meet and their lateral morraines form morraine in middle)
• morraines are poorly sorted, varied clasts, usually unstratified.

define:

1. lodgement tills
2. esker
3. kame
4. drumlin
5. ribbed moraine
6. rouche moutennee

1. debris from melting of basal ice, have fabric
2. subglacial stream deposit
3. mounds of sand/gravel from in crevasses
4. whale-shaped subglacially formed, parallel to flow
5. drumlin formed transverse to flow
6. erosional tear drop feature pointing downflow

• unstratified diamictites go to stratified diamictites
• fans and lobes from meltwater
• melting iceberg seds
• meltwater plumes
• density currents
• gravity deposits

• rain-out debris
• ice-rafted debris (dropstones, lonestones, dump structures)
• sed plumes
• gravity flows
• plowing of seafloor by icebergs