wjec a2 geology
DESCRIPTION
WJEC A2 Geology. BGS Mapwork. Recognising Geological Structures. I.G.Kenyon . Moreton-in-Marsh 1:50,000 Sheet 217. Horizontal beds Evidence + symbols Bed outcrops run parallel to contour lines Outcrop pattern controlled by relief/topography. +. Youngest bed. Oldest bed LLi. - PowerPoint PPT PresentationTRANSCRIPT
WJEC A2 GeologyBGS Mapwork
I.G.Kenyon
Recognising Geological Structures
Moreton-in-Marsh1:50,000 Sheet 217
+
+
Horizontal beds
Evidence + symbols
Bed outcrops run parallel to contour lines
Outcrop pattern controlled by relief/topography
Youngest bed
Oldest bed LLi
No strike and dip values can be given
Moreton-in-Marsh1:50,000 Sheet 217
Graben
Horst
Ticks on faults indicate downthrown side
Graben
Moreton-in-Marsh1:50,000 Sheet 217
Outliers-areas of younger rock completely surrounded by older rock
Cheddar 1:25,000 Sheet ST 45
Older Carboniferous
Limestone
Younger Triassic red mudstone
Inlier-an area of older rock completely surrounded by younger rocks
Unusually this inlier also forms a hill
Anticlinal Axis
N
South side dips more gently (dips 25-30°) Outcrops wider
North side dips more steeply (dips 42-60°) Outcrops narrower
Slight plunge to the east as core bed gets narrower in outcrop
Cheddar 1:25,000 Sheet ST 45
Asymmetrical Anticline
Oldest bed in the core of the fold
Repeated outcrop pattern, only core bed
is not repeated
Cheddar 1:25,000 Sheet ST 45
DCg is a basal conglomerate and is unconformable on the
older carboniferous rocks
DCg shows angular overstep here as it extends
over several older rocks
+
+
Upper younger series are horizontal
Lower older series dip North 60-80° and strike East-West
MMG overlaps DCg here
+
Monmouth 1:50,000 Sheet 233
C3 quartz conglomerate forms a parallel unconformity between the upper and lower old red sandstone
Beds above and below unconformity have parallel outcrop patterns and
the same dip and strike values
Angular overstep unconformity here
between the carboniferous limestone and the upper
coal measures
Craven Arms 1:25,000 Sheet SO48 Solid & Drift
Account for the V shaped pattern of outcrop of bed b7b here
Malmesbury One inch Sheet 251 Solid & Drift
Describe the strike and dip of the Carboniferous beds here
Identify the relationship between beds d5 and f6 here
Malmesbury One inch Sheet 251, Solid & Drift
Describe the main fold structure here, refer to strike and dip values, symmetry and plunge
Name this feature
Haverfordwest 1:50,000 Sheet 228
Describe the main fold structure here, refer to strike and
dip values, symmetry and plunge
Chepstow 1:50,000 Sheet 250
Describe the main fold structure here, refer to strike and dip
values, symmetry and plungeApproximate
position of fold axis
Chepstow 1:50,000 Sheet 250This fault dips east at 79°,
identify the fault type
Identify this deposit and account for its distribution
on this map extract
Haverfordwest 1:50,000 Sheet 228
Describe and identify the main fold structure in the map extract above. Refer to dip and strike values, symmetry and plunge where appropriate
Identify this feature
Haverfordwest 1:50,000 Sheet 228
Identify the relationship between beds (b4 and d4) and (d2 and d4) in this box
Describe and identify the main fold structure in the map extract above. Refer to dip and strike
values, symmetry and plunge where appropriate
Hawes 1:50,000 Solid & DriftDescribe the evidence
on the map for the Carboniferous beds GL
and DBL being horizontal
Describe the fold structures in the InG beds within this box
Chepstow 1:50,000 Sheet 250
Describe the strike and dip of the Carboniferous
beds BRL, BRD, GuO and CDLin this box
Identify an angular unconformity on the map extract and locate examples of overstep and overlap
Cockermouth 1:50,000 Sheet 23
Identify an area of Step-Faulting and a Horst Block on the map extract
If the Crummock and Waverbank Faults dip North East, what
type of faults are they?
Ayr 1:50,000 Sheet 14(W)
If this fault dips steeply to the SSW, what is the type of fault?
Ayr 1:50,000 Sheet 14(W)
Describe the main fault trends on the extract above. Identify 2 Grabens, 2 Horst Wedges and an area of Step Faulting
Carmarthen 1:50,000 Sheet 229 Solid
This fault plane dips steeply to the South East. Identify the type of fault
This fault plane dips steeply to the South East. Identify the type of fault
Carmarthen 1:50,000 Sheet 229 Solid
Name the types of faults F1 and F2 on the cross section above
F1 F2
Alloa 1:50,000 Sheet 13 Solid
Account for the repeated outcrop of bed dc2 on the map extract above
Alloa 1:50,000 Sheet 13 Solid
Describe and identify the major fold structure on the map extract above. Refer to dips and strikes, symmetry and plunge where appropriate.
Alloa 1:50,000 Sheet 13 Solid
The Ochil Fault dips at a high angle to the South. Which is the downthrown side? What type of fault is the Ochil Fault?
Account for the variation in width of the metamorphic aureole
Metamorphic Aureole
Brough-under-Stainmore 1:50,000 Sheet 31 Solid
Describe the outcrop of the quartz dolerite qD and outline the likely nature of this igneous intrusion
Chapel en le Frith 1:50,000 Sheet 99 Solid
Identify 2 major fold structures on the map extract above Refer to dip and strike, symmetry and plunge where appropriate
Chapel en le Frith 1:50,000 Sheet 99 Solid
Describe the relationship between geological structure and topography on the cross section above.
Comment on the areas highlighted by the boxes.
Winchester 1:50,000 Solid & Drift
Identify the major fold structure on the map extract above
Cross section shown on next slide
a
b
a b
Winchester 1:50,000 Solid & Drift
Describe and explain the relationship between topography and structure on the cross section above
Grampound Grit
Falmouth Series
Mylor Series
Portscatho Series
Falmouth 1:50,000 Sheet 352 Solid & Drift
Truro School
Inliers-outcrops of older rock completely surrounded by younger rocks
Quartz Porphyry Dykes
River Allen
River Kenwyn
Mica-rich dykes (Minette)
Sediments are Devonian 408-360 Ma
The End
Ash deposits of the Las Canadas Volcano, Tenerife, Canary Islands