Vertical build up of a sedimentary sequence. Usually occurs when there is a relative rise in sea level produced by subsidence and/or eustatic sea-level rise, and the rate of sediment influx is sufficient to maintain the depositional surface at or near sea level (i.e. carbonate keep-up in a HST [highstand systems tract] or clastic HST). Occurs when sediment flux = rate of sea-level rise. Produces Aggradational stacking patterns in parasequences when the patterns of facies at the top of each parasequence are essentially the same (modified from Posamentier, 1999, Wilgus et al., 1988, Emery, 1996).

A parasequence set in which successively younger parasequences are deposited above one another with no significant lateral sifts. The rate of accommodation approximates the rate of deposition.

Lateral outbuilding, or progradation, of strata in a sea-ward direction. Progradation can occur as a result of a sea-level rise accompanied by a high sediment flux (causing a regression). This latter usually occurs during the late stages of the development of a highstand systems tract and/or an early lowstand systems tract. A Progradational stacking pattern of parasequences refers to the pattern in which facies at the top of each parasequence becomes progressively more proximal (Posamantier, 1999, Wilgus, 1988, Emery, 1986).

A parasequence set in which successively younger parasequences are deposited farther basinward; overall the rate of deposition is greater than the rate of accommodation.

The movement of coastline land-ward in response to a transgression. This can occur during a sea-level rise with low sediment flux. Retrogradational stacking patterns of parasequences refer to patterns in which facies become progressively more distal when traced upward vertically (Posamantier, 1999, Wilgus, 1988, Emery, 1996).

A parasequence set in which successively younger parasequences are deposited farther landward in a backstepping pattern. Overall, the rate of deposition is less that the rate of accommodation.

A landward movement of the shoreline indicated by a landward migration of the littoral facies in a given stratigraphic unit. (Mitchum, AAPG Memoir 26)

Layers of the Earth

The Crust: This region is thin compared to the other layers in the Earth. It varies in thickness from 10km deep to 65km deep. The crust is made up of lighter rocks that "float" on top of the mantle. This layer includes the continents as well as the rock under the oceans. The thickness of the crust might be a little deceiving... to put it into perspective, we have built many deep mines but NONE have yet reached the mantle! The Mantle: This region lies under the crust and is approximately 2900km thick. The mantle is much denser than the crust (which is why the crust floats on top) and has a texture much like tar. The rock in this region is rich in compounds made from iron, magnesium, and silicon which accounts for why it is denser than the crust. The Core:This region is divided into two parts. The outer part is called the Outer Core. It is about 2100km thick and made of liquid nickel and iron. The inner part is called the Inner Core and it is the real centre of the Earth. This part is about 2800km in diameter and is made of solid iron and nickel.

A base-disconrdant relation in which initially horizontal strata terminate progressively against an initial inclined surface, or in which initially inclined strata terminate progressively updip against a surface of greater initial inclination

A base-discordant relation in which initially inclined strata terminate downdip against an initially horizontal or inclined surface. (Mitchum, AAPG Memoir 26)

Horizontal deltaic deposit composed of coarse alluvial sediment. Represents current or past surface of the delta Termination of strata against an overlying surface mainly as a result of non deposition (sedimentary bypassing) with perhaps only minor erosion. (Mitchum, AAPG Memoir 26)

A term describing termination of strata along the lower boundary of a depositional sequence, used only where discrimination between onlap and downlap is difficult or impossible (Mitchum, AAPG Memoir 26).

Termination of strata or seismic reflections interpreted as strata along an unconformity surface due to post-depositional erosional or structural effects. (Mitchum, AAPG Memoir 26)

A surface of erosion or non-deposition separating younger strata from older rocks, along which there is evidence of subaerial erosional truncation (and, in some areas, correlative submarine erosion) or subaerial exposure, with a significant hiatus indicated. Exxon group modified this definition to "a surface separating younger from older strata, along which there is evidence of subaerial erosional truncation (and, in some areas, correlative submarine erosion) or subaerial exposure, with a significant hiatus indicated" (Seismic Stratigraphy, AAPG Memoir 26) .

Angular conformity: younger sediments rest upon the eroded surface of tilted or folded older rocks. Disconformity: contact between younger and older beds is marked by a visible, irregular or uneven erosional surface. Paraconformity: beds above and below the unconformity are parallel and no erosional surface is evident; but can be recognized based on the gap in the rock record. Nonconformity: develops between sedimentary rock and older igneous or metamorphic rock that has been exposed to erosion.

Angular unconformity at Siccar Point in Scotland led James Hutton to utter (ca. 1786), on the enormity of geological time, " ...that we find no vestige of a beginning, no prospect of an

Disconformity by San Juan River, Paradox Basin, Southeastern Utah.

Types of Stress

This is an example of the effect of Compression Stress: This is an example of the effect of Tension:

This is an example of a Lateral Fault.

Tension pulls the rocks, causing them to stretch over a larger area

Compression squeezes the rocks of the crust. This causes the rocks to take up less space and become denser (they have more matter in a smaller volume).

Shearing is when rock of the crust pushes in two opposite directions and usually results in a simple bend or break.

AA break or planar surface in brittle rock across which there is observable displacement.

Fault plane A fault plane is a plane used to represent an actual fault, or a particular segment of a fault. Faults are generally not perfectly flat, smooth planes, so this may not be a true representation of the fault. However, since faults do typically act as planes (even though some, in fact, are so physically complex that trying to draw their structure would be cumbersome and confusing), defining a fault plane is the most convenient way to represent and model a fault.Horizontal plane It is useful to have a reference plane when measuring the characteristics of faults. The standard reference plane is the horizontal. It usually approximates the Earth's surface, but does not vary. Here, the horizontal plane shown is that of sea level, but a horizontal plane of any altitude or depth can be used for reference.Surface trace (or Fault line) The intersection of a fault plane with the Earth's surface produces what is known as the surface trace of the fault. This intersection is also known as a fault trace, or a fault line, since this is the line drawn to represent a fault on a standard map. The traces of faults are not always obvious at the surface. Some, however, display themselves quite plainly, particularly when the observer knows what to look for.

Trend The trend of a fault trace is the general direction it takes across the Earth's surface. Trend may be used to average out the small, localized bends of a long fault and talk about its overall directionality. This direction is often similar to the strike of a fault (see next page), but the two are fundamentally different, and should not be interchanged. Hanging wall For a non-vertical fault, this is the part of the Earth's crust above the plane of the fault. Its name originates from mining activities along large, ancient faults which had since been "filled in" with mineral deposits. Miners could hang their lamps from the wall above them, coining the term "hanging wall" for this side of a fault.Footwall The counterpart of the hanging wall, the footwall is the part of the Earth's crust below a fault. As with the hanging wall, the "footwall" was so named by miners, since they would walk on the lower side of a mined-out fault.

A type of fault in which the hanging wall moves down relative to the footwall, and the fault surface dip is steep, commonly from 45o to 90o. Groups of normal faults can produce horst and graben topography, or a series of relatively high- and low-standing fault blocks, as seen in areas where the crust is rifting or being pulled apart by plate tectonic activity. A growth fault is a type of normal fault that forms during sedimentation and typically has thicker strata on the downthrown hanging wall than the footwall.

This is a Normal Fault

Reverse Fault is a type of fault formed when the hanging wall of fault block moves up along a fault surface relative to the footwall. Such movement can occur in areas where the Earth's crust is compressed. A thrust fault, sometimes called an over thrust if the displacement is particularly great, is a reverse fault in which the fault plane has a shallow dip, typically much less than 45o.

This is a Thrust Fault

This is a Reverse Fault

A type of fault whose surface is typically vertical or nearly so. The motion along a strike-slip fault is parallel to the strike of the fault surface, and the fault blocks move sideways past each other. A strike-slip fault in which the block across the fault moves to the right is described as a dextral strike-slip fault. If it moves left, the relative motion is described as sinistal. Local deformation near bends in strike-slip faults can produce pull-apart basins and grabens. Flower structures are another by-product of strike-slip faults. A wrench fault is a type of strike-slip fault in which the faultA surface is nearly vertical

OBLIQUE-SLIP FAULT Oblique-slip faulting suggests both dip-slip faulting and strike-slip faulting. It is caused by a combination of shearing and tension of compressional forces.

Parts of a fold: fold axis axial plane limb

symmetrical asymmetrical overturned - tipped in one direction so that one of the limbs is overturned recumbent - lying on its side dome basin

Thrust development in mountain belts

Anticline - Syncline Animation

Overturned folds in the Baltimore Gneiss Baltimore County, Maryland Ensor Mill Road, along stream, off I-83.

The Divisions of Precambrian Time

Paleozoic Era

The chart at left shows the several subdivisions of the Cenozoic Era. After the column labelled "Cenozoic", the next column shows the two periods, the Tertiary and the Quaternary.

The right-hand column lists the six major epochs into which the periods are divided.

http://www.greatgeophysics.com/logginginfo.html#G. LOGGING OF LIMESTONE AND DOLOMITEhttp://www.connect.slb.comhttp://www.kgs.ukans.edu/Dakota/vol1/petro/petro05.htmhttp://google.yahoo.com/bin/query?p=the+spontaneous+potential+well+log&hc=0&hs=0http://www.psigate.ac.uk/ROADS/subject-listing/earth/num-earth.html