geological section maps

TOPOGRAPY OF MAP:On West direction there is a hill and on east there is a high ground. There are two valleys running in

opposite direction so there is a saddle between them. One valley runs in NE direction and other valley

runs in SE direction.

ATTITUDE OF MAP:

Strike Direction: North – South

Dip Direction: East – West

Amount of Dip: 1: 5

ORDER OF SUPERPOSITION:

B – Youngest

L – 60m

P–30m

Y – 60m

T – 120 m

D– Oldest

GEOLOGICAL HISTORY:In the area of deposition of bed ‘D’ was deposited

first and successively overlained by T, Y, P, L and B beingthe youngest of all. The area was then uplifted and

eroded to give rise to the present topographic position.

SECTIONAL VIEW OF MAP NO. 1

TOPOGRAPY OF MAP:1. There is a valley in the South – West Direction.2. There are two high grounds:

1st Ground in the Direction of North – West.2nd Ground in the Direction of East – South.

ATTITUDE OF MAP:Strike Direction: North West – South EastDip Direction: South – WestAmount of Dip: 1: 5ORDER OF SUPERPOSITION:T – YoungestA – 60 mP – 45 mL – Oldest-------------------- Unconfirmity.G – YoungestO – 60 mN – 30 mY – Oldest.GEOLOGY:Series 1: TAPL

There are no strike lines or dip in the series.Series 2: GONY

Strike lines are in NW to SE and dip direction towards SW.

GEOLOGICAL HISTORY:There are two series:

SERIES 1:This series is Horizontal series TAPL. L bed being oldest and T bed is the Youngest.

SERIES 2:‘Y’ being the Oldest bed and ‘G’ being the Youngest bed. Series 2 was deposited first

in the geological time scale. The there was a gap of interval for depositing the bedseries. i.e. Unconformity. The there was a upliftment of beds. i.e. the beds werecompletely over turned hence the oldest bed Y is near to the second series and the

Youngest bed is at the last.

SECTIONAL VIEW OF MAP NO. 2

TOPOGRAPY OF MAP:There is an elongated hill located in central part of the Map with the height elevation of 450 m contour.

ATTITUDE OF OLDER SERIES (P,D,C,L,V):

Strike Direction: North West – South East

Dip Direction: North – East.

Amount of Dip: 1: 5.

ATTITUDE OF YOUNGER SERIES (K,M,B):

Strike Direction: East– West

Dip Direction: North.


INTRUSIONS:

There are three intrusions i.e.

1. Dolerite. 2. Pegmatite. 3. Aplite

ATTITUDE OF DOLERITE:

It is a vertical dyke, with thickness: 40 m

ATTITUDE OF PEGMATITE:

Strike Direction: South East– North West

Dip Direction: South East.


Thickness of Dyke: 30 m.ATTITUDE OF APLITE:

It is a vertical dyke with thickness: 40 m

ORDER OF SUPERPOSITION:

B – Youngest

M – 60 m

K – Oldest.

-------------------- Unconformity.

V – Youngest

L – 60 m

C – 60 m

D – 60 m

P – OldestGEOLOGICAL HISTORY:In this basin of deposition bed P was deposited firstly and successively overlained by the beds P, D, C, L and V. Theseries was intruded by the vertical dyke of Dolerite. The area was then uplifted and eroded, this period of depositionof beds and erosion is marked by the unconformity. After unconformity the deposition of younger series took place inwhich K deposited firstly followed by M and B bed. Then there was a intrusion of Aplite followed by the Pegmatite

dyke. Pegmatite dyke is inclined dyke while Aplite dyke is the vertical dyke.

TOPOGRAPY OF MAP:There is circulated hill situated at the centre of the map.ATTITUDE OF MAP:

Strike Direction: East – WestDip Direction: SouthAmount of Dip: 1: 3

ORDER OF SUPERPOSITION:P - YoungestM - 20 mT - 20 mB - 20 mL - Oldest

GEOLOGICAL HISTORY:There is only one series. The order of deposition of beds is P, M, T, B, and L. There are two different

faults i.e. Vertical Fault parallel to each other.ATTITUDE OF FAULTS:

There are two vertical faults. The down throw amount forFault 1: 10 mFault 2: 10 mSOLUTION OF ENGINEERING PROBLEM:Alternative 1:

A road along 65 m contour on the northern slope, along 65 m contour on the southern slope, the dipof the beds and slope of the strata are in the same direction. Hence risk of slide (Land) is more. However onthe northern slope dip is towards South and the strata slope is in opposite direction. Hence constructing aroad along 65 m contour on the northern slope is more feasible.Alternative 2:

Constructing a tunnel with the invert of 65 m and crown of 71 m has a problem. There are twovertical faults, F1 and F2, if the tunnel is constructed as give above due to the faults there is a possibility ofdislocation of the beds, due to faulting the chances of seepage of water through the fault plane is more. Hence

the given site location for constructing a tunnel is rejected.

TOPOGRAPY OF MAP:There is a position of high ground in North Western portion of the map as well as in the

South Western part too with contour value of 350 m. there is a valley flowing east andextends towards west.

GEOLOGY OF AREA:There is a confirmable series of beds Y, O, L and D. The series is affected by a vertical dip

fault.ATTITUDE OF MAP:Strike Direction: North – SouthDip Direction: Towards WestAmount of Dip: 1: 10ORDER OF SUPERPOSITION:Y – YoungestO – 60 mL – 30 mD – Oldest

GEOLOGICAL HISTORY:In the basin of deposition bed D was deposited first and successivelyoverlained by L, O and Y bed. The area was then uplifted and eroded. The serieswas uplifted by a vertical dip fault with displacement amount of about 150 m.

finally erosion of the surface takes place giving rise to present topography.

TOPOGRAPY OF MAP: There are 6 high grounds with one valley, also there is 1 saddle.

Valley V1 running towards North direction.Valley V2 running towards South direction.ATTITUDE OF MAP:Strike Direction: East – West Dip Direction: South Amount of Dip: 1: 5ORDER OF SUPERPOSITION:T- YoungestA - 10 mP - 10 mL - 10 m

S – Oldest

GEOLOGICAL HISTORY:In the basin of deposition ‘S’ was deposited first successively overlained by beds L, P,

A and T forming the youngest bed. The area was then uplifted and tilted and finallyeroded to give the present topography.

SOLUTION OF ENGINEERING PROBLEM:Alternative 1:

A ground is constructed along 85 m contour from A to C with bridge at C to D. Inthis case the geological and topographical slope is in the same direction and possibilityof landslide is more. If the road is constructed along 85 contour from B to D with bridgeat A to B then that will the best alternative.

Alternative 2:Constructing of CD dam, as the beds dip towards south if the wall of dam is at C. it

could be subjected to high pressure of the reservoir. As the given lithology consist of ajointed limestone which does not have high bearing capacity and presence of joints doesnot favor the construction of the dam.

Quartzite though is a rock with high compressive strength, it is also jointed. Alsothe Shells occurring at the site can swell due to absorption of water.

Due to above reasons construction of the dam at CD location is rejected.

TOPOGRAPY OF MAP:One elongated hill situated at the corner and the single valley in the given geological

map.ATTITUDE OF MAP:Strike Direction: East - WestDip Direction: NorthAmount of Dip: 1: 3ORDER OF SUPERPOSITION:D - YoungestN - 10 mK - 20 mC - 10 mB - 20 mG - 30 mV - 20 m

L - Oldest

GEOLOGICAL HISTORY:

The bed ‘L’ was deposited firstly in the basin of the deposition successively followed bythe beds V, G, B, C, K, N and D. The area was then uplifted due to tectonic activity and due toerosion the present topography exists.

SOLUTION OF ENGINEERING PROBLEM:

The 3 sites given for construction of dam are O – P, Q – R and S – TIn case of O – P, the catchments area is more than the other two sites. Though there is

a possibility of seepage in some parts it can only be resulted in reduction of storage capacityof the reservoir.

In case of Q – R, the dam will be constructed in comparatively younger beds with lesscatchments area, hence rejected for constructing a dam.

In case of S – T, the slope occurs along the dip direction and hence the pressure whichis created will affect the dam. Hence from the 3 sites, Site O – P is the most suitable site forthe construction of the dam and the capacity of the reservoir catchments will be more

compared to other two.

TOPOGRAPY OF MAP:There is a valley running towards West and East side of the given

geological Map.ATTITUDE OF MAP:Strike Direction: North – SouthDip Direction: In West part of Map dip is towards West direction

In East part of Map dip is towards East direction.Amount of Dip: 1: 4ORDER OF SUPERPOSITION:S – YoungestD – 60 mO – 30 mJ – 60 mC –Oldest

GEOLOGICAL HISTORY:There is a Fold present with anticline and syncline type as indicated

by the dip direction.

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