report of survey - maharashtrareport of survey. india ... 2.1 horizontal control was established in...

REPORT OF SURVEY

INDIA - WEST COAST

HYDROGRAPHIC SURVEY OF PAWAS BAY

SURVEYED BY B.ASHOK KUMAR, S/10447/IS

01 MAY TO 10 MAY 08

SCALE - 1: 10 000

BA/IOS/10447/IS AUGUST 2008

REPORT OF SURVEY

INDIA-WEST COAST

BATHYMETRIC AND GEOPHSICAL SURVEY AT SATPATI MMB PORT

SURVEYED BY

SKW SOIL AND SURVEY CO.

29 Apr to 19 May 2017

SKW/ROS/MMB/2017/01

23 May 2017

INDIA WEST COAST

BATHYMETRIC AND GEOPHYSICAL SURVEY AT SATPATI MMB PORT

SURVEYED BY

SKW SOIL AND SURVEY CO.

(29 Apr to 19 May 2017)

1: 1,000

REPORT OF SURVEY

SKW/ROS/MMB/2017/01

23 May 2017

CONTENTS

PART 1 – DESCRIPTIVE 1. Introduction 2. Geodetic Control 3. Digital Surveying System 4. Navaids 5. Bathymetry 6. Side Scan Sonar 7. Sub Bottom Profiler 8. Magnetometer 9. Tides and Sounding Datum

BATHYMETRIC AND GEOPHYSICAL SURVEY AT SATPATI MMB PORT

PART – I DESCRIPTIVE 1. INTRODUCTION 1.1 Aim. The Bathymetric and Geophysical Survey at Satpati MMB Port was carried out by SKW Soil and Survey Co. in compliance with Maharashtra Maritime Board Work Order ----------------dated -------- 2017. The Survey was carried out from 29 Apr to 19 May 2017. 1.2 Limits of Survey. The Survey was undertaken as per the Work Order issued by Maharashtra Maritime Board on the scale of 1:1,000. The bathymetric survey was carried out as per the proposed area drawing provided by the client. 1.3 Weather. The weather was conducive for bathymetric survey early in the day only. Visibility was good throughout the survey. 2. GEODETIC CONTROL 2.1 Horizontal control was established in WGS-84 datum and the area of the survey was plotted on Universal Transverse Mercator Grid (Zone 43) on a scale of 1: 1,000 with central meridian 75º E. 2.2 The DGPS corrections transmitted from SBAS satellite were received continuously and used for the sounding operations during the entire duration of survey. Geomax Zenith 25 Pro DGPS was used on the Survey Motor Boat for position fixing during sounding operations. 3. DIGITAL SURVEYING SYSTEM 3.1 The single beam data from Odom Echotrac MK II Dual Frequency echo sounder operating at 200 KHz along with the differential positions obtained from Geomax Zenith 25 Pro DGPS was logged on to the HYPACK digital data logging software. A fixed Sound Velocity of 1500 m/s was used to give input to the echo sounder as well as subsequent applications during the post processing stage. 3.2 Edgetech 4100 Full Spectrum Side Scan Sonar was used for side scanning in the survey area with range scale 50 m and maximum altitude of three metres. 3.3 Geo Acoustics Geo Pulse Sub Bottom Profiler along with Coda DA 2000 Digital data acquisition system was used to carry out sub bottom profiling along the navigational channel. 3.4 Data processing and Final Chart. The raw digital data from bathymetry was processed in HYPACK and exported to AutoCAD for creation of the final chart. 3.5 All significant depths detected by the echo sounder are represented on the digital records. This has been achieved by very close comparison of the digital data in HYPACK with the echo roll and selecting appropriate logging options during the data collection stage.

3.6 The details of Digital Surveying System are placed at Annexure ‘B’ to Part II of this report. 4. NAVAIDS 4.1 Geomax Zenith 25 Pro DGPS with SBAS corrections was used in the Survey Motor Boat for accurate position fixing throughout the conduct of survey. The DGPS corrections transmitted from satellite were received continuously and used for the sounding operations during the entire duration of survey. The receiver was configured to output data in GGA, VTG and ZDA data string at a rate of 1 second in WGS-84 Datum. Details of the Navaids are placed at Annexure ‘D’ to Part II of this report. 5. BATHYMETRY 5.1 General. Odom Echotrac MK III Dual Frequency Echo Sounder operating at 200 kHz was used for sounding operations. The data was logged directly into HYPACK software. 5.2 Sounding Operations. (a) The principal sounding lines using single beam Echo Sounder were run at a spacing of 10 m on ground. (b) The final drawing of the entire survey area has been plotted on a Scale of 1: 1,000 and the same is being forwarded as an accompanying document along with the Report of Survey. 5.3 Single Beam Sounding. Odom Echotrac MK III Dual Frequency Echo Sounder operating at 200 kHz was used for single beam sounding by the Survey Motor Boat. The speed of advance for sounding operations was restricted between 4 to 5 knots for the Survey Motor Boat. The data was logged directly onto the HYPACK software and the digital data display of the echo sounder was closely monitored. Bar Check was carried out on each day for calibrating Echo Sounder. The details are placed at Annexure ‘E’ to Part II of this report. Area which could not be covered by boat has been covered using Geomax Zenith 25 Pro RTK system. 6. SIDE SCAN SONAR 6.1 Edgetech 4100 Full Spectrum Side Scan Sonar was used for side scanning with range scale 50 m and average altitude of 1.5 m. Discover software was used to record the side scan data in native JSF format and later post processed for preparing mosaic and analysis of the side scan data. 6.2 No significant contacts were found throughout the survey area. 7. SUB BOTTOM PROFILER 7.1 Geo Acoustics Geo Pulse Sub Bottom Profiler along with Coda DA 2000 Digital data acquisition system was used to carry out sub bottom profiling along the navigational channel at 30 m interval.

8. MAGNETOMETER 8.1 Magnetometer survey was carried out using SeaSpy2 Marine Magnetometer. However, no magnetic anomalies were found in the survey area. 9. TIDES AND SOUNDING DATUM 9.1 Water level records were obtained from tide gauge set up near passenger jetty at Satpati Port. A record of same is placed at Annexure ‘F’ to Part II of this report. 6.2 The Bench Mark provided by MMB within the premises of Satpati MMB Port Office was used for reduction of soundings. The value of Bench Mark was found to be 6.896 m above CD. Virendra Patil Project Head

CONTENTS

PART II – TECHNICAL

ANNEXURE DESCRIPTION

A Accompanying Documents

B Digital Surveying System

C Geodetic Data

D Nav Aids

E Sound Velocity and Bar Check Observations

F Tidal Observations

G Side Scan Sonar

H Sub Bottom Profiler

I Magnetometer

J List of Personnel

K Views

Annexure ‘A’

ACCOMPANYING DOCUMENTS S No Document Qty (i) CD Containing All raw/ processed data and drawings 01 Nos. (ii) Echo Rolls 02 Nos.

Annexure ‘B’

DIGITAL SURVEYING SYSTEM B.1 Data Logging. The data was logged on HYPACK data acquisition system. The data was processed using HYPACK and final chart generated using AutoCAD. B.2 Data Processing. The digital bathymetric data collected using HYPACK was processed. The position processing was undertaken with respect to speed jump, distance jump and course made good. No filters were applied for depth processing in the Single Beam Editor for the data collected by Survey Motor Boat. The water levels observed by Dam authorities were applied to the processed data and was merged thereafter. The processed data was then exported to AutoCAD for preparation of final drawing. B.3 Creating a Final Chart. The final chart was prepared in AutoCAD with the following main parameters: -

(a) Scale - 1: 1,000

(b) Projection - Universal Transverse Mercator

(c) Grid Zone - 43 North

(d) Central Meridian - 75° E

(e) Ellipsoid - WGS 84

(f) False Easting - 500000

(g) False Northing - 0

B.4 Geomax Zenith 25 Pro DGPS receiver with Odom Echotrac MK III Dual Frequency echo sounder were interfaced with the boat data logging system. The system configuration used for data logging is as mentioned below:- (a) DGPS

(i) Offset - NIL

(ii) Record - Always

(iii) Record - Raw data

(iv) Record - Quality data

(b) Odom Echotrac MK III

(i) Offset - NIL

(ii) Record - Always

B.5 Depth Processing. No depth filters were defined to reject any soundings B.6 Contour. Contours were drawn using HYPACK and then exported to AutoCAD. B.7 Side Scan Sonar. Side scanning was carried out using Edgetech 4100 Full Spectrum Side scan sonar using Discover software. B.8 Sub Bottom Profiler. Sub Bottom Profiling was carried out using Geo Acoustics Geo Pulse Sub Bottom Profiler at 30 m interval along the channel. B.9 Equipment Brochures. Brochures of all equipment used for survey are placed at Enclosure I to this Annexure.

Enclosure I to Annexure ‘B’

EQUIPMENT BROCHURES

Annexure ‘C’

GEODETIC DATA C.1 Horizontal control was established in WGS-84 datum and the area of the survey was plotted on Universal Transverse Mercator projection on a scale of 1: 1,000 with Zone No. 43 North, central meridian 75º E. C.2 The DGPS corrections transmitted from SBAS satellite were received continuously and used for the sounding operations during the entire duration of survey. Geomax Zenith 25 Pro DGPS was used on the Survey Motor Boat for position fixing during sounding operations. The receiver was configured to output data in GGA, VTG and ZDA data string at a rate of 1 second in WGS-84 Datum.

Annexure ‘D’

NAV AIDS

D.1 Geomax Zenith 25 Pro DGPS was used in differential mode for position fixing by the Survey Motor Boat throughout the conduct of survey. The DGPS corrections were received directly from satellite using SBAS. The receiver was configured to output data in GGA, VTG and ZDA data string at a rate of 1 second in WGS-84 Datum.

Annexure ‘E’

SOUND VELOCITY AND BAR CHECK OBSERVATIONS E.1 A fixed sound velocity of 1500 m/s was set on echo sounder and used for data acquisition as well as processing. E.2 Bar Check was carried out to calibrate the echo sounder every day prior to start of sounding.

Annexure ‘F’

TIDAL OBSERVATIONS Tides and Sounding Datum. F.1 A flat tide gauge set up by MMB was used to observe water levels throughout the survey duration. F.2 The value of Bench Mark as provided by MMB is 6.896 m above CD. F.3 Observed tidal records are placed at Enclosure I to this Annexure.

Enclosure I to Annexure ‘F’

TIDAL RECORDS AT SATPATI

29-Apr-17 19-May-17 Time Tide Time Tide 12:30 3.45 12:08 2.39 12:45 3.80 12:23 2.46 13:00 4.20 12:38 2.53 13:15 4.45 12:53 2.60 13:30 4.75 13:08 2.67 13:45 4.85 13:23 2.74 14:00 5.15 13:38 2.81 14:15 5.25 13:53 2.88 14:30 5.40 14:08 2.95 14:45 5.50 14:23 3.02 15:00 5.60 14:38 3.09 15:15 5.60 14:53 3.16 15:30 5.60 15:08 3.23 15:45 5.57 15:23 3.30 16:00 5.50 15:38 3.37 16:15 5.36 15:53 3.44 16:30 5.22 16:08 3.51 16:45 5.07 16:23 3.58 17:00 4.92 16:38 3.65 17:15 4.72 16:53 3.72 17:30 4.55 17:08 3.79 17:45 4.35 17:23 3.86 18:00 4.20 17:38 3.93 18:15 4.05 17:53 4.00

18:08 4.07

18:23 4.14

18:38 4.07

18:53 4.00

Annexure ‘G’

SIDE SCAN SONAR

The side scanning was carried out using Edgetech 4100 Full Spectrum Side Scan Sonar operating at 100 kHz with 50 m range scale. The definitions of Seabed Features within the surveyed areas were primarily achieved through the examination of side scan sonar data acquired. Additionally, appropriate reference to corresponding the echo sounder, sub-bottom profiler data was also done wherever necessary. In interpreting and plotting seabed features from the side scan sonar records, a certain amount of distortion is manifest, which is influenced by various factors like boat manoeuvring, tow fish traverse, layback, bottom currents, sea state etc. Changes in current patterns and steering corrections make the tow fish roll, pitch and yaw and deviate from its expected straight-line path. All these limitations have a direct effect on the accuracy of position and dimensions of the sonar features plotted. Hence due to these limitations, the accuracy of all sonar features plotted is expected to be ±5 meters. Hence it should be noted that geophysical side scan sonar interpretation is a qualitative approach and not a quantitative one. No significant features or debris was observed in the present survey area. The Sonar records revealed that the area is composed of silty sand mainly.

Annexure ‘H’

SUB BOTTOM PROFILER

Geo Acoustics Geo Pulse Sub Bottom Profiler was used to carry out sub bottom profiling along the navigational channel at 30 m interval. Seismic reflection profiles are roughly analogous to geological cross sections of sub-bottom materials because acoustic characteristics are usually related to lithology. Reflections can appear on the seismic record as a result of subtle changes in acoustic impedance that are associated with minor lithological differences between under and overlying materials. Conversely, significant lithologic differences might not be recorded because of similar acoustic impedance values between bounding units, because of minimal thickness of stratigraphic units or because reflectors are masked by gas. Some of these complicating factors can mislead interpretation of the seismic record, seismic stratigraphy should always be considered tentative until supported or verified by direct lithologic evidence from core samples. The two most important parameters of sub-bottom seismic reflection systems are vertical resolution (i.e., the ability to differentiate closely spaced reflectors) and depth of penetration. Penetration of acoustics energy was achieved up to a few centimetres in depth of the bed rock in the present survey area. Acoustic energy penetrated through the interface consisting of fine silty sand underlain by another interface of compacted coarse to medium hard grain sand. The dissipation of acoustic energy was observed with a few centimetres into the bed rock. Correlation of sub-bottom profiler records along with adjacent lines also contributed to arriving at the distribution of the below mentioned stratigraphic units.

Annexure ‘I’

MAGNETOMETER

Magnetic Survey was carried out using SeaSpy2 Magnetometer. The survey area was found to be devoid of any ferrous material, obstructions and objects. No magnetic anomalies were detected.

Annexure ‘J’

LIST OF PERSONNEL

The following personnel participated in the survey:-

S No Name Designation

1 Virendra Patil Project Head

2 Jitendra Aher Project Coordinator

3 Bhanwar Singh Hydrographic Surveyor

4 Dharmendra Kumar Senior Surveyor

5 Pankaj Tiwari Survey Engineer

6 Sanjay Verma Surveyor

Annexure ‘K’

VIEWS