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| 855286777 | Geochonological Time Units | References Actual Time Eons > Eras > Periods > Epochs > Ages ex: Permian Late, Middle, Early Global | 1 | |
| 855286778 | Chronostratigraphy | Lithological Units, the actual rocks May or may not correlate to GeoChrono Eonothem> Erathem> Systems > Series > Stages Upper, Middle, Lower Local | 2 | |
| 855286779 | GSSP | Global Boundary Stratotype Section and Point (Golden Spike) A point that defines the end of one time unit and the beginning of another It has a definite, facies independent, often a fossil, but can be any global change Has to be continuous, protected, easily accessible, lots of correctable info (bio, magno, isotopes, ect) | 3 | |
| 855286780 | Lithostratigraphic unit | Defined by sediment characteristic and stratigraphic position | 4 | |
| 855286781 | Allostratigraphic Unit | Defined by position relative to unconformities or correlateable events (Event Stratigraphy) | 5 | |
| 855286782 | Chronostratigraphy Unit | Has upper and lower isochoronous layer | 6 | |
| 855286783 | Isochronous layer | A surface formed at one time | 7 | |
| 855286784 | Unconformity | Break is sedimentation with deformation and erosion | 8 | |
| 855286785 | Disconformity | A break in sedimentation with erosion but no deformation | 9 | |
| 855286786 | Formation | A body defined by its lithologic characteristics Laterally traceable Some degree of homogeniy Min. comp, texture, primary sed. struct., and fossil content can all be defining along with lithology Not age or fossil defined Often diachoronous Named after nearby geography | 10 | |
| 855286787 | Diachronous | deposited in a different time and place but lithologically the same | 11 | |
| 855286788 | Member | rock unit with limited extent within a formation | 12 | |
| 855286789 | Beds | V. distinct part of a formation due to lithology or fossil content | 13 | |
| 855286790 | Group | 2 or more assc. formations often defined by unconformities | 14 | |
| 855286791 | supergroups | 2 or more groups | 15 | |
| 855286792 | Type section | where the lithologic characteristics of a form., and hopefully the top and bottom are visible | 16 | |
| 855286793 | Way up markers (fossils) | Tree Stumps Tracks, Trails Burrows Geopetal Stable orientation of convex shells | 17 | |
| 855286794 | Way up markers (sed structures) | Cross stratification (beds) scours ripped up clasts weathered surfaces wave ripple crests mudcracks normally graded beds | 18 | |
| 855286795 | Lithodermic Unit | Non sed. rock equivalent of a formation Group = Suite Complex = group for deformed rx | 19 | |
| 855286796 | Timelines | Imaginary lines drawn across and between rx that represent a moment in time Dating, Fossils, Magneto- can all be used | 20 | |
| 855286797 | Temporal framework | Correlated timelines | 21 | |
| 855286798 | Lacuna(e) | Hiatus in sed. represented by a bedding plane | 22 | |
| 855332553 | Holotype | The fossil the sets the standard for the species | 23 | |
| 855332554 | Morphometrics | Size and shape statistics help define a species | 24 | |
| 855332555 | Zone Fossils | Define a biozone The best : Live for a short time Wide range Very common Fast Evolution | 25 | |
| 855332556 | Biozone | A strat unit defined by zone fossils theoretically independent of lithology, but continuous fossils often means continuous environments | 26 | |
| 855332557 | Interval BZ's | Taxon-range Concurrent-range Partial Range Lineage of consecutive | 27 | |
| 855332558 | Assemblage BZs | 3 Taxa that may or may not be related define an interval | 28 | |
| 855332559 | Acme BZs | Uses abundance to define an interval Unreliable as local factors can affect abundance | 29 | |
| 855332560 | Useful Microfossils | Formanifera Radiolaria Calcreous Nanoplankton Diatoms | 30 | |
| 855332561 | Geological Events | Storm Floods Tsumanis Volcanoes Meterorite Imacts Sea Level Changes | 31 | |
| 855332562 | Biological Evets | Biohorizons Oxygen Levels (lack of oxygen) | 32 | |
| 855332563 | Climate events | warm, cold periods | 33 | |
| 855332564 | Cause of Sea Level change (Eustatic) | Thermal Expansion Volume Change (midocean ridges, super-continents) Mass Ice Caps Water exchange with continents | 34 | |
| 855332565 | Regional Sea level Change causes | Wind (Ekman Effect) Tectonics | 35 | |
| 855332566 | Ekman Effect | Uneven storm pressures on sides opposite sides of the ocean cause up welling on the side with storms (warmer) due to wind mvmt | 36 | |
| 855332567 | Highstand | Progradation of sediments due to accumulation | 37 | |
| 855332568 | Falling Stage | Erosion due to lower sea level | 38 | |
| 855332569 | Lowstand | Progradation due to stable sea level | 39 | |
| 855332570 | Transgressive System Tract | Retrogradation due to higher sea level rise | 40 | |
| 855332571 | Retrogradation | Landward change of river delta sediments due to higher sea level | 41 | |
| 855360075 | Chem. Strat: Bulk analysis | Easy to do, difficult to interpret there can be many reasons for chemical shifts, not sure provenance change, such as change in grain size Regional | 42 | |
| 855360076 | Chem. Strat: Heavy Mineral Assemleages, Isotopes | Takes more time, but is more accurate representing provenance changes Global | 43 | |
| 855360077 | Chem Strat | Formation dependent, thus similar to lithostratigraphy | 44 | |
| 855360078 | Stronium Isotope dating | Sr is found less often the Ca in limestones Sr has two isotopes, 86 and 87 due to weatering and oceanic crust production. The ratios have changed over time (86 constant), giving a known curve, giving several possibilities Only possible with unaltered calcite producing fossils, aragonite alters over time to calcite | 45 | |
| 855360079 | Oxygen Isotope Stratigraphy | 2 Oxy isotopes O16, O18, which fractionate based on temp, higher temps, more O18 in atmosphere, thus less in ocean water In ocean sediments with high O18, the earth was colder, reverse with ice cores Globally Syncronized | 46 | |
| 855360080 | SMOW | Standard Mean Ocean Water Ratios of Oxy isotopes today | 47 | |
| 855360081 | PDB | Pee Dee belemnite, the standard for O18 levels | 48 | |
| 855360082 | Carbon 13 | A stable C isotope, the ratio varies with amount of photosynthesis, with organics having low C13 levels Higher Photosyn, higher C13 levels Again matched against a known curve, and PBD Deep water has less C13 due to more C12 sinking | 49 | |
| 855379510 | PETM | Paleocene/Eocene Thermal Maximum Characteristic warming of Deep ocean by 5C | 50 | |
| 855379511 | Marine Isotope Stage | A set of known peaks of O18 values in the record, alternating cold and warm, starting with 1 as the modern day | 51 | |
| 855379512 | Eccentricity Cycle | 100ky how eccentric orbit is | 52 | |
| 855379513 | Obliquity Cycle | 41ky Change of tilt of the earth | 53 | |
| 855379514 | Precession Cycle | changes between 19 and 23ky Which direction points towards the sun at aphelion | 54 | |
| 855379515 | aphelion | point in the orbit, where an object is farthest from the object which it is orbiting | 55 | |
| 855379516 | Effect of Orbital Cycles | Affect Insolation, more insolation, more heat With changes in heat, deep sea sediments change too, more heat, higher CCD | 56 | |
| 855379517 | Sadler Effect | Sedimentation rate is discontinuous, spans 11 orders of magnitude. | 57 | |
| 855455989 | Sedimentation Rate | SR = SD/ST SR =/= Accumulation Rate | 58 | |
| 855455990 | Dansgaar-Oeschker (D-O) | A series of rapid climate changes within the last glacial period thought to happen every 1450yrs (debated) | 59 | |
| 855455991 | Production/Accumulation Cycles | Cycles can influence what seds are deposited, or how much, or how diluted they are | 60 | |
| 855455992 | Redox Cycles | Changing amount of oxygen in ocean waters can affect the coloration of rocks, from red (abundance of oxygen), to drab or white (normal conditions) to black (lack of oxygen). The variation of the amount of oxygen can be absolute (a changing ocean circulation) or simply brought on by a changing water depth caused by a sea-level variation. This would simply move the minimum oxygen depth from one location to another. | 61 | |
| 855455993 | Algorithms | Convert depth into a numerical age Can be linear or nonlinear Requires continuous sedimentation to work | 62 | |
| 855455994 | Control Point | A point with a known age through dating or correlation | 63 | |
| 855455995 | Useful Environs: Biostratigraphy | Fossils Reefs Terrestrial Sediments Soils | 64 | |
| 855455996 | Useful Environs: Varvechronology | Terrestrial Sediments | 65 | |
| 855455997 | Useful Environs: Astrochronology | Terrestrial and Marine Seds | 66 | |
| 855455998 | Useful Environs: Dendrochronology | Bogs, Trees | 67 | |
| 855455999 | Useful Environs: Tephrochronology | Terrestrial and Marine Sediments | 68 | |
| 855456000 | Useful Environs: Radiometric | Everything | 69 | |
| 855456001 | Useful Environs: Oxy isotopes | Terrestrial, Marine Sediments Soils Fossils Reefs Evaporites | 70 | |
| 855456002 | Useful Environs: Magnetostrat | Ter. Marine Sed. Soils | 71 | |
| 855456003 | Useful Environs: Luminecense | Ter. sed Soils | 72 | |
| 855456004 | Cosmogenic Nucleides | Cosmic bombardment leads to creation of isotopes, and at a more or less constant rate. This allows us to learn how long something has been exposed for 3 isotopes are created 10Be, 26Al, 21Ne, 36Cl | 73 | |
| 855456005 | Radiocarbon Dating | Actual Halflife: 5730+- 40 Libby Halflife: 5568+-30 C14 is taken up by organic matter. When it dies, uptake stops. The ratio of C14 estimated, or taken from dendchronology, and with a known halflife, we can determine the age | 74 | |
| 855456006 | C14/C12 Ratio | Affected by geomagnetic field solar variability global carbon budget (nuclear testing) | 75 | |
| 855456007 | 40K/40Ar Dating | Most widely used in sed.rx due to glauconite, and Feld. and Mica being K rich (volcanics) 11% of 40K decays to 40Ar, the rest to 40Ca. As Ar is a gas, some escapes, leading to underestimates of the age | 76 | |
| 855456008 | 39Ar-40Ar Dating | The ratio between the two is constant 39K is converted to 39Ar by neutron bombardment, the sample along with a standard, providing how much 39K was converted to 39Ar. This provides an indirect measure of 40Ar | 77 | |
| 855456009 | Rb-Sr Dating | Igneous rx 87Sr and 86Sr ratios are constant within magma bodies, different between them ???!!!???? | 78 | |
| 855887799 | Uranium-Lead Dating | Uranium decays to thorium, radon, and lead Two most important: 238U > 206Pb 235 >207Pb Naturally occurring ratios of isotopes constant | 79 | |
| 855887800 | Luminescence dating | Sed rx are exposed to ionising radiation from naturally occuring radioactive elements. Within mineral crystals, some energy is trapped in the lattice, and can be released as light with application of heat. At the surface this energy is bleached out. Useful for dating when something was buried up to 150ka | 80 | |
| 855887801 | Half-lives and Dating ranges: 40K > 40Ar | HL: 1.25*10^3 1 to >4500Ma | 81 | |
| 855887802 | Half-lives and Dating ranges: 87Rb > 87Sr | 48.8*10^3 10 to >4500Ma | 82 | |
| 855887803 | Half-lives and Dating ranges: C14 | Actual: 5730yrs +-40 Libby: 5568yrs +-30 <.07Ma (70,000yrs) | 83 | |
| 855887804 | Half-lives and Dating ranges: U235 > 207Pb | .704*10^3 10 to >4500Ma | 84 | |
| 855887805 | Half-lives and Dating ranges: U238 > Pb206Pb | 4.468*10^3 10 to >4500Ma | 85 | |
| 855887806 | Half-lives and Dating ranges: Luminescence | up to 150ka | 86 | |
| 855887807 | Half-lives and Dating ranges: Oxy Isotope | End of Quaternary (~2.6Ma) | 87 | |
| 855887808 | Half-lives and Dating ranges: Cosmogenic Isotopes | Tens of thousands | 88 | |
| 855887809 | Half-lives and Dating ranges: Amino-acid Racemisation | Temp and material dependent thousands to hundreds of thousands | 89 |
