06.struktur sedimen
Post on 25-Feb-2018
304 Views
Preview:
TRANSCRIPT
-
7/25/2019 06.Struktur Sedimen
1/41
06 Struktur Sedimen
Petrologi Batuan Karbonat
-
7/25/2019 06.Struktur Sedimen
2/41
Kerangka Materi
Pendahuluan: Struktur Sedimen Primer
Definisi
Burrows
Borings
Geopetal fabrics
Fenestral fabrics
Stromatactics
Lamination
-
7/25/2019 06.Struktur Sedimen
3/41
Pendahuluan:
Struktur Sedimen Primer
-
7/25/2019 06.Struktur Sedimen
4/41
PRIMARY SEDIMENTARY STRUCTURES
Primary sedimentary structures are physical and/or biological
features formed during the process of sediment deposition.Generally such structures are best seen in outcrop, core, orpolished hand sample, but smaller features such as borings orfenestral fabrics are both readily apparent in thin section andimportant to recognize. Their identification can improve
interpretations of depositional environments and can alsohelp to decipher patterns and timing of diagenesis.
The characteristic features for the recognition andinterpretation of primary sedimentary structures are providedin the figure captions. Diagenetic sedimentary structures, such
as hardgrounds, soil crusts, or stylolites, are covered in theappropriate diagenetic chapters.
-
7/25/2019 06.Struktur Sedimen
5/41
Definitions
Borings - Openings created in relatively rigid rock, shell, or other material by boring organisms.The rigid host substrate is the feature that distinguishes borings from soft-sediment burrows.
Burrow porosity - Feature created by organic burrowing in relatively unconsolidated sediment,in contrast to borings. Most burrows collapse, become filled with sediment, or are back-filled bythe burrow-forming organism itself.
Fenestrae (fenestral fabric) - Primary or penecontemporaneous gaps in rock framework largerthan grainsupported interstices. Such features may be open pores or may have been partially orcompletely filled with internal sediment and/or sparry cement. Fenestrae occur as somewhatrounded features of spherical, lenticular, or more irregular shapes; their large size in comparisonto normal interparticle openings and their multigranular roofs, floors, and other margins are keycharacteristics. Fenestrae are commonly somewhat flattened parallel with the laminae. They
may, however, be round or very irregular, and some are elongate in a vertical dimension.Although isolated fenestrae occur in sedimentary carbonates, it is more common to find many inclose association. Fenestrae are generally associated with microbial mats and result fromshrinkage, gas formation, organic decay, trapping of air through swash-zone wave action, orother synsedimentary processes (Choquette & Pray, 1970).
Geopetal structure - Any internal structure or organization of a rock indicating originalorientation such as top and bottom of strata. Common examples are internal sedimentaccumulating on the floor of a cavity which it partly fills, or solution-collapse residue that hasfallen to the bottom of a vug or cave.
Stromatactis - A cavity structure common in muddy carbonate sediments, typically 3 to 10 cm indiameter, characterized by a flat floor and an irregular roof. The floor of this former cavitytypically is overlain by peloidal internal sediment; the remaining void is filled with marinecement or later sparry cement. These poorly understood vugs have been attributed to the decayof unknown soft-bodied organisms, to gas formation in impermeable sediments, to gravitysliding and shear, to the alteration of sponges and sponge holdfasts, and to several other causes.
-
7/25/2019 06.Struktur Sedimen
6/41
Burrows
-
7/25/2019 06.Struktur Sedimen
7/41
Burrow
-
7/25/2019 06.Struktur Sedimen
8/41
Burrow
-
7/25/2019 06.Struktur Sedimen
9/41
Burrow
-
7/25/2019 06.Struktur Sedimen
10/41
Burrow
-
7/25/2019 06.Struktur Sedimen
11/41
Borings
-
7/25/2019 06.Struktur Sedimen
12/41
Boring
-
7/25/2019 06.Struktur Sedimen
13/41
Boring
-
7/25/2019 06.Struktur Sedimen
14/41
Boring
-
7/25/2019 06.Struktur Sedimen
15/41
Boring
-
7/25/2019 06.Struktur Sedimen
16/41
Boring
-
7/25/2019 06.Struktur Sedimen
17/41
Boring
-
7/25/2019 06.Struktur Sedimen
18/41
Boring
-
7/25/2019 06.Struktur Sedimen
19/41
Geopetal Fabrics
-
7/25/2019 06.Struktur Sedimen
20/41
Geopetal
-
7/25/2019 06.Struktur Sedimen
21/41
Geopetal
-
7/25/2019 06.Struktur Sedimen
22/41
Geopetal
-
7/25/2019 06.Struktur Sedimen
23/41
Fenestral Fabrics
-
7/25/2019 06.Struktur Sedimen
24/41
Fenestral fabrics
-
7/25/2019 06.Struktur Sedimen
25/41
Fenestral fabrics
-
7/25/2019 06.Struktur Sedimen
26/41
Fenestral fabrics
-
7/25/2019 06.Struktur Sedimen
27/41
Fenestral fabrics
-
7/25/2019 06.Struktur Sedimen
28/41
Stromatactics
-
7/25/2019 06.Struktur Sedimen
29/41
Stromatactics
-
7/25/2019 06.Struktur Sedimen
30/41
Stromatactics
-
7/25/2019 06.Struktur Sedimen
31/41
Laminations
-
7/25/2019 06.Struktur Sedimen
32/41
Lamination
-
7/25/2019 06.Struktur Sedimen
33/41
Lamination
-
7/25/2019 06.Struktur Sedimen
34/41
Eroded Surface Contact
-
7/25/2019 06.Struktur Sedimen
35/41
Terima Kasih
Ada Pertanyaan?Minggu Depan:
Semen
-
7/25/2019 06.Struktur Sedimen
36/41
-
7/25/2019 06.Struktur Sedimen
37/41
-
7/25/2019 06.Struktur Sedimen
38/41
-
7/25/2019 06.Struktur Sedimen
39/41
Geopetal
Geopetal structure in bivalve boring in coral; bivalve shell
visible; Matmor Formation (Middle Jurassic), southern Israel.
-
7/25/2019 06.Struktur Sedimen
40/41
-
7/25/2019 06.Struktur Sedimen
41/41
top related