Chapter 2 Primary Sedimentary Structures ● Main types of bedding O Determination of younger direction of beds from primary structures Types of stratigraphic break Angular unconformity O Soft sedimentary structures
Chapter 2 Primary Sedimentary Structures ● Main types of bedding ● Determination of younger direction of beds from primary structures ● Types of stratigraphic break ● Angular unconformity ● Soft sedimentary structures
Tt Main Bedding Types. Bedding Shape level bedding ripple bedding 2 ain Iypes o f plate [3 amina Bedding wedge trough graded bedding
Main Types of Bedding level bedding ripple bedding cross -bedding graded bedding plate laminae wedge trough Main Bedding Types Bedding Shape
;∵∵·∴·∴ “··; Graded Bedding Fine grains distribute in the whole bed. coarse grains decrease from the :· bottom to the top
Graded Bedding Fine grains distribute in the whole bed, coarse grains decrease from the bottom to the top
甲· a8。嚣"● ●:∵ 88 B C D 图2-4根据粒级层理确定岩层顶、底面 (据M. P. Billings,) 一水乎岩层,每层自底到顶由粗变细B~正常倾斜岩层,顶面在左上方C一顶面在 右边的直立岩层D-顶面在左下方的倒转岩层 Determination of the top and bottom surfaces from graded bedding AB-normal beds.C- vertical beds. Overturned beds
Determination of the top and bottom surfaces from graded bedding A, B– normal beds; C– vertical beds; D– overturned beds
A B C 图2-4根据交错层理确定岩层顶、底面 A.顶面在左边,正常层序;B.岩层直立,顶面在右边;C.顶面在右边,岩层倒转 Determination of the top and bottom surfaces from cross-bedding, the oblique laminae converge to the bottom of the bed A-normal beds, top to the top left; B-vertical beds, top to right; C-overturned beds, top to the bottom right
Determination of the top and bottom surfaces from cross-bedding, the oblique laminae converge to the bottom of the bed A– normal beds, top to the top left; B– vertical beds, top to right; C– overturned beds, top to the bottom right
CROSS-BEDDING, Silurian system, Jiangxi province
CROSS-BEDDING, Silurian system, Jiangxi province
Large cross Bedding
Large CrossBedding
顶 印模 波峰 波谷 图2-5波痕及其印模 图2-6泥裂的立体示意图 (据R.R. Shrock,1948) (据R.R. Shrock,1948) Ripple mark and its Mud cracks Mold The sharp ends of the Wave crest points to the top wedge points to the and wave trough points to bottom of the bed the bottom of the bed
Ripple Mark and its Mold Wave crest points to the top and wave trough points to the bottom of the bed Mud Cracks The sharp ends of the wedge points to the bottom of the bed
会 图2-8不同形态的叠层石 纹层凸向顶面 Stromatolite in Different Shapes The laminae protrude to the top surface
Stromatolite in Different Shapes The laminae protrude to the top surface
■國。 砂岩.硅质岩灰岩交错层硅质岩砾石 Scour surface And Its Relation To The Sequence Of The Beds The sandstone beds are over the silicalite beds note the gravels in the bottom bed of the sandstones
Scour surface And Its Relation To The Sequence Of The Beds The sandstone beds are over the silicalite beds, note the gravels in the bottom bed of the sandstones
