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What is System tract in sequence stratigraphy?

What is System tract in sequence stratigraphy?

(A ‘systems tract’ is the term used in sequence stratigraphy for strata deposited during a stage of a depositional sequence.) The beds show either an aggradational or a progradational pattern as the shoreline shifts seawards across the shelf.

What are systems tracts?

systems tract Genetically associated stratigraphic units that were deposited during specific phases of the relative sea-level cycle (Posamentier, et al, 1988). These units are represented in the rock record as three-dimensional facies assemblages.

What is a systems tract geology?

1. n. [Geology] Subdivisions of sequences that consist of discrete depositional units that differ in geometry from other systems tracts and have distinct boundaries on seismic data. Different systems tracts are considered to represent different phases of eustatic changes.

What is transgressive systems tract?

The transgressive systems tract (TST) comprises the deposits accumulated from the onset of coastal transgression until the time of maximum transgression of the coast, just prior to renewed regression.

What is LST in sequence stratigraphy?

A lowstand systems tract (LST) forms when the rate of sedimentation outpaces the rate of sea level rise during the early stage of the sea level curve. It is bounded by a subaerial unconformity or its correlative conformity at the base and maximum regressive surface at the top.

What is type 1 sequence boundary?

A type 1 sequence boundary is defined to be a sequence boundary “characterized by subaerial exposure and concurrent subaerial erosion associated with stream rejuvenation, a basinward shift of facies, a downward shift in coastal onlap, and onlap of overlying strata”.

What is correlative conformity?

A correlative conformity is a depositional surface that correlates to a subaerial unconformity. Moreover, a depositional sequence is the record of one cycle of relative sea level, that is, a fall and rise in relative sea level.

What is depositional sequence in geology?

A depositional sequence is defined as a relatively conformable succession of genetically related strata bounded by subaerial unconformities or their correlative conformities.