Field Trip to Palolem, Goa

On our geological field trip on April 8 2021, through the western coast of Goa in India under the guidance of Prof. Malcolm Afonoso and Prof. Swati Ghadi, we visited impressive rock formations, volcanic intrusions, geomorphic characteristics as well as windy climate zone of Palolem Beach facing the Arabian Sea. Elevation of Palolem village is only 5 meters above sea level. The formations that we visited were right on the coast of the village. Consequently, the local summer weather remained unwavering throughout the time of our surveying, and the cloudless blue sky brought up the hot temperatures under the scorching sun.

 In the course of our visit to the study area, Prof. Malcolm explained us the objectives of the field work and briefed us about the area.He spoke about the geological and topographical setting of the beach in Palolem, and also about the clinometer compass that we used to find the dip and trends of the rock structures. 

 Our field trip started at around 8.30 AM in the morning of 8 April 2021, in Fatorda which is a suburb of the City of Margoa and ended at the sunset, around 5.30 PM when we reached back to the college, reviewing everything that we studied that day during the return travel time in the bus. 

 On the first site that we visited, we got to examine a granite outcrop which showed strong signs of weathering such as exfoliation possibly due to the scorching heat of the summer and cycles of rain. Root wedging was also identified on one side of the formation where roots of the growing plants were penetrating the fractures of the rock and thereby adding to the physical weathering of rock. The rock was rounded and rough on one side with smaller grains from the rock’s surface eroded away and the larger grains still intact indicating occurrence of erosion from that direction. The reddish tint in the small portion of the rock facing the beach indicates oxidation which is a type of chemical weathering.
 

The second site which was separated from the first site by a small hill, it showed a quartz vein within the TTG outcrop from the hill. However, the rock formation changed at the foot of the hill; an amphibole schist with a green colored dolerite dyke within it,  trending from East-West laid exposed from the ground. Initially, the rock showed indications of  ductile deformation due to stress such as folding. As it got extended towards the sea, a new rock chemistry was observed. The new rock formation that we came across in the sea water showed highly schistose texture along with granitic intrusion throughout its structure. Furthermore, this rock mass showed signs of weathering such as salt wedging and chemical weathering caused by growing algae. 

 The third study site brought us to an area which exposed schistose rock formation, which, got intruded with pegmatite intrusion trending towards N105°. Since most of the part was hidden within the hill and under the sea, we couldn’t study the formation further. The focus on the fourth site and our last study area was on testing our identification skills and finding the dip direction and trending of the intrusions within the TTG formations using the clinometer compass. There were dark mafic intrusions trending towards N45°. The participating students also got to learn about the application of clinometer compass to find bearings of the distant objects. 

 Our field to Palolem was accompanied by many positive experiences. We learned how to communicate with the native people and our colleagues while on the field for the benefit of an effective field survey. But the most important thing is that we learned a lot about our beautiful country and countryside, the people, the ecosystems, the style of living, and especially the outstanding geology of India. It was a great advantage for our studies. 

To summarise, this field trip was one of the most fascinating and informative trips we have ever been on and would like to acknowledge support from the professors of our Geology Department at Parvatibai Chowgule College of Arts & Science (Autonomous). 

- Contributed by Nashvelle Fernandes
                            TY student

Comments

Popular posts from this blog

WORKSHOP ON GIS

Visit ONGC Ipshem at Betul, Goa on 24th July 2019

Induction of the committee of Club Nebulites by the Geology Department