National Institute of Oceanography Dona Paula, Goa – 403 004 Cruise Report: MDV (Leg-1 to Leg-4) From 12/11/2013 to 12/12/2013 Bathymetry and Sub-seabed Survey off Malvan- Devgad-Vijaydurg, West Coast of India Project Coordinator Name: Dr. AK Chaubey
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National Institute of Oceanography Dona Paula, Goa – 403 004
Itinerary of the boat: Leg-1A: Embarkation MFB Phalguni at Malvan: 12/11/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Malvan: 14/11/2013 at 18:00 hrs.(IST) Leg-1B: Embarkation MFB Phalguni at Malvan: 16/11/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Malvan: 18/11/2013 at 18:00 hrs.(IST) (b) Leg-2A & 2B
S. No. Name of the participants Designation 1 Shri. V. Mahale Scientist 2 Shri. V. Khedekar Principal Tech. Officer. 3 Shri. G. M. Phadthe Sr. Tech. Officer (3) 4 Shri. S.S. Gaonker Sr. Tech. Officer (3) 5 Shri. S. Vaz Technical Officer 6 Shri. K.M. Dubey Junior Research Fellow
Itinerary of the boat: Leg-2A: Embarkation MFB Phalguni at Malvan: 20/11/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Malvan: 22/11/2013 at 18:00 hrs.(IST) Leg-2B: Embarkation MFB Phalguni at Malvan: 24/11/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Devgad: 26/11/2013 at 18:00 hrs.(IST)
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(c) Leg-3A & 3B
S. No. Name of the participants Designation 1 Dr. A.K. Chaubey Chief Scientist 2 Shri. P. Marathe Principal Tech. Officer. 3 Shri. S.S.Gaonker#/ Shri. G.A. Walker* Sr. Tech. Officer (3) 4 Shri. Areef Sardar Sr. Tech. Officer (2) 5 Shri. G.Tirodkar Technical Officer 6 Shri. D.Srinivas Project Assistant
Itinerary of the boat: Leg-3A: Embarkation MFB Phalguni at Devgad: 28/11/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Devgad: 30/11/2013 at 18:00 hrs. (IST) Leg-3B: Embarkation MFB Phalguni at Devgad: 02/12/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Vijaydurg: 04/12/2013 at 18:00 hrs. (IST) * Shri G.A. Walker arrived Devgad on 01.12.2013 for Leg 3B survey and continued thereafter. # Shri S.S. Gaonkar left from Devgad to Goa on 01.12.2013 after completion of Leg 3A. (d) Leg-4A & 4B
S. No. Name of the participants Designation 1 Shri. V. Mahale Scientist 2 Shri. D. Gracias Principal Tech. Officer. 3 Shri. G. M. Phadthe Sr. Tech. Officer (3) 4 Shri. G.A. Walker Sr. Tech. Officer (3) 5 Shri. S. Vaz Technical Officer 6 Shri. Rajeev Yadav Project Assistant
Itinerary of the boat: Leg-4A: Embarkation MFB Phalguni at Vijaydurg: 06/12/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Vijaydurg: 08/12/2013 at 18:00 hrs.(IST) Leg-4B: Embarkation MFB Phalguni at Vijaydurg: 10/12/2013 at 07:00 hrs. (IST) Disembarkation MFB Phalguni at Vijaydurg: 12/12/2013 at 18:00 hrs.(IST)
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Boat’s complement: Sr. No. Name of the crew Designation
##Vaidya Kunal Bhupendra participated during the survey till 22.11.2013 only. Objective of the survey: Seabed and sub-seabed investigations comprising bathymetry and high resolution
shallow seismic off Malvan-Devgad-Vijaydurg to study seismic stratigraphy and Paleo-
drainage pattern during the Quaternary period.
Project No: OLP1207 Data Acquisition: Bathymetry and sub-bottom profiling surveys between ~12 m and ~65 m water depth
were carried out to investigate the seabed and sub-seabed off Malvan-Devgad-
Vijaydurg along proposed survey tracks (Fig. 1) using echosounder and high-
resolution shallow seismic system. For conducting the survey, standard survey
procedures were followed using following equipment:
(i) Beacon ready Differential Global Positioning System for positioning and
navigation.
(ii) Dual frequency (33 and 210 kHz) echosounder for bathymetry.
(iii) High resolution shallow seismic digital sparker system for sub-bottom profiling.
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Fig. 1 Survey tracks off Malvan-Devgad-Vijaydurg (MDV) along which bathymetry and shallow seismic data were acquired.
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A fishing boat 'MFB Phalguni' from Mumbai was hired to carry out the survey. The
boat arrived from Mumbai at Old Goa Jetty on 08.11.2013. After installation of
equipment and trial survey, the boat sailed to Malvan on 10.11.2013 and arrived at
Malvan on 11.11.2013. The survey commenced from Malvan on 12.11.2013 and
continued till 12.12.2013. In the following sections, a brief description about the data
acquisition is presented.
Navigation data
Differential Global Positioning System (DGPS) manufactured by Trimble (Model 4000
SE) along with the differential beacons (operating in 283.5 to 325 kHz band) was used
for the positioning during the survey. The system, being differential, overcomes the
error caused by disturbances in ionosphere - troposphere and other errors. The
system comprised of two GPS receivers, Pro Beacon receiver [antenna and pre
amplifier, antenna cables and radio receiver]. The Pro Beacon receiver uses
advanced digital signal processing technique to track and demodulate the signals from
DGPS's radio beacon.
The navigation data was logged using windows based HYPACK® software during the
survey. The HYPACK® software provides tools to (i) design preplanned survey track
lines, (ii) navigate along the planned track lines, (iii) provide position data to other
geophysical systems (echosounder and high resolution sub-bottom profiler), (iv) log
raw position and depth data and (v) realize the quality control in real time navigation.
Continuous monitoring of navigation data quality was carried out online using display
system both at recording room and wheel house of the vessel.
All data were recorded on hard disk of the recording computer and later copied to the
portable hard disc. The time stamping to navigation, bathymetry and shallow seismic a
data was accomplished in Greenwich Mean Time (GMT) provided by the Global
Positioning System (GPS) receiver clock throughout the survey.
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Bathymetry data
Atlas Deso-30 single beam echosounder with frequency transducer of 33 kHz was
used to acquire depth data along track lines. The system was interfaced with
navigation system for digital depth logging and event generation. The data was
additionally logged as a hard copy on a built-in thermal recorder.
In hydrographic surveying, depth is determined from observation of 'two way travel
time' of reflected acoustic waves from seabed. An acoustic pulse transmitted by a
transducer, travels through the water column and is then reflected by the target
(seabed) back to the receiver transducer. Depth is calculated from the measured
travel time as given below:
Depth = C*(T/2)
where “C” is the sound speed in the water. Basic echosounder measures the two way
travel time (T) through water column.
Shallow seismic data
High resolution seismic system comprising of energy source CSP D700 & multi-tips
squid spark array, data acquisition unit Octopus 760 and 20 element hydrophone
array from M/s Applied Acoustics, UK was used to acquire sub-bottom information in
the survey area. The seismic data was acquired along the tracks (Fig. 1) using 300
joules energy at a recording frequency band of 250-2500 Hz at a boat speed of ~4.0
knots.
Chief Scientist Name: A.K. Chaubey Sign: ________________ MDV (Leg-1 to Leg-4)
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FORMAT FOR SUBMISSION OF INFORMATION FOR UNDERWAY DATA ACQUISITION DURING CRUISE
Name of Boat: MFB Phalguni Cruise No: Malvan-Devgad-Vijaydurg survey
Cruise Period: From 12/11/2013 to 12/12/2013 Name of Chief Scientist: Dr. A.K. Chaubey
Area of Operation: Offshore Malvan, Devgad & Vijaydurg, west coast of India
Line ID Beginning of Line End of line Type of data