Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
49 Cards in this Set
- Front
- Back
Cemented beach sands are common in which diagenetic environment?
|
Marine Vadose (Intratidal - Supratidal)
|
|
Cements in modern beach rocks typically consist of which carbonate mineral?
|
Aragonite
|
|
The formation of cemented beach sands typically occurs how far below the surface
|
10's of cm
|
|
Microbial micritisation is common in which diagenetic environment?
|
Marine Phreatic (Shallow Subtidal Marine)
|
|
Formation of grapestones and aggregates is common in which diagenetic environment?
|
Marine Phreatic (Shallow Subtidal Marine)
|
|
Carbonate dissolution commonly occurs in which diagenetic environment?
|
Meteroic Vadose
|
|
What is the defining feature of isopachous cements?
|
It forms an equal rim of cement around a grain
|
|
As rainwater is undersaturated with respect to CaCO3, this leads to which process?
|
Dissolution
|
|
As water moves downwards through the meteoric vadose zone via diffuse or conduitflow it become saturated in CaCO3 so that cementation occurs. These cements aretypically what type of carbonate?
|
Low-Mg Calcite
|
|
Name a carbonate mineral that is highly susceptible to dissolution?
|
Aragonite
|
|
In arid settings what is the typical rate of alteration?
|
Slow.
|
|
Ferroan cements contains elevated concentrations of which element?
|
Iron
|
|
Name an environment in which cementation takes place where CaCO3 enriched watersresult from evaporation?
|
Cave systems.
|
|
With respect to carbonate diagenesis principle cements types include aragonite; highMgcalcite; low-Mg calcite and dolomite. Name a less common cement type associatedwith carbonate diagenesis?
|
Ankerite.
Siderite. Quartz. |
|
Slow and continuous cementation processes in the meteoric phreatic diageneticenvironment lead to what type of cement morphologies?
|
Large blocky Calcite spars
|
|
Increasing ambient Mg/Ca supply combined with increasing carbonate ion supplytypically leads to which cement morphology?
|
Acicular
|
|
In which latitudes is seawater supersaturated with respect to CaCO3 today?
|
The Tropical Latitudes (~25o N/S)
|
|
What is the surname of the geologist who devised the Facies code system for fluvialdeposits?
|
Miall
|
|
What does a sedimentary facies allow the interpretation of?
|
Sedimentary processes
|
|
What does a facies association allow the interpretation of?
|
The environment of deposition
|
|
Name a sedimentary process that is typical of alluvial fan environments?
|
Sheetflood.
Debris flow. |
|
In stratigraphy, what is the name of the law that describes the arrangement ofsedimentary facies in space and time?
|
Walther's Law
|
|
Name an environmental controlling factor that can result in the development of acoarsening or fining upwards facies sequence?
|
Climate
|
|
An alluvial fan with a low surface slope and a large catchment area will be dominated bywhat kind of sedimentary process?
|
Sheetflood
|
|
An alluvial fan with a steep surface slope and a small catchment area will be dominatedby what kind of sedimentary process?
|
debris flow
|
|
Name a facies model for an alluvial fan setting?
|
Miall, 1977.
Scott, 1967. |
|
Meandering river channels can often undergo avulsion. Name a cut off process thatresults in avulsion?
|
Neck Cut-off.
Shute cut-off. |
|
Palaeosols in floodplain deposits that show grey mottling indicate what kind of climaticsetting?
|
Humid climate
|
|
What is a lake setting characterised by evaportic sediments called?
|
Playa lake
|
|
The development of evaporitic minerals on a lake floor will result in the formation ofwhat kind of surface cracks?
|
Desiccation cracks
|
|
What kind of basin fill geometry is formed within a symmetrical rift basin?
|
Graben
|
|
What kind of sedimentary environment characterises the footwall setting of a terrestrialrift basin?
|
Alluvial fan
|
|
The axis of an externally drained rift basin is dominated by what kind of sedimentaryenvironment?
|
Axial drainage channel
|
|
What is the collective name of the sedimentary facies that develops within theunderfilled stage of foreland basin development?
|
Flysch sediments
|
|
What is the collective name of the sedimentary facies that develops within the overfilledstage of foreland basin development?
|
Mollasse sediments
|
|
What are the main deltaic-sub environments?
|
Pro-delta.
Delta front. Delta Plain. |
|
What are the main sub-environments in a delta plain?
|
Distributary channels.
Interdistributary Bays |
|
What are names of the two processes which deliver sediment from distributary channelsto inter-distributary areas?
|
Crevassing.
Overbank-flooding. |
|
What kind of facies successions typify minor mouth bar progradation?
|
Coarsening up cycles, found in delta plain successions
|
|
What kind of dense flows deliver coarse sediment to the distal delta front and prodelta?
|
Hyperpycnal
|
|
Hypopycnal conditions are occur when?
|
Low density flowing water, meets higher density standing water
|
|
What is the key difference between failure-induced turbidites and hyperpycnalturbidites on delta fronts? |
Hyperpycnites differ from other turbidites because of their well-developed inversely graded facies andintrasequence erosional contacts - Mulder, et al 2003. |
|
Normal regression in deltas generates what kind of facies succession?
|
Coarsening up, shallowing up succession
|
|
What sedimentary features are typical of delta front successions which are not found inoffshore shelf deposits?
|
Heterolithic clinoforms
|
|
Which type of sedimentary structure is unique to the offshore transition zone?
|
Hummocky Cross Stratification
|
|
Palaeocurrent distributions from trough cross bedding deposited in the upper shorefaceare likely to show what kind of distribution?
|
Parallel to the palaeo-shoreline
|
|
The thicknest successions in nearshore facies are likely to be deposited during what kindof genetic behaviour?
|
Progradation associated with Normal Regression
|
|
What flow regime does parting lineation develop in?
|
Upper Flow regime
|
|
What kind of genetic behaviour occurs when sediment supply rate in the nearshore zoneis greater than the rate of relative sea-level rise?
|
Normal regression
|