Master10
Indian Geography15 Concepts & Facts

Coastal Plains & Islands of India: Konkan, Malabar & Andaman

India's coastline spans 7,516 kilometers, bounded by contrasting littoral margins and two offshore archipelagos. The Western Coastal Plain is a narrow, submerged shoreline formed by continental downfaulting during the Cretaceous breakup of Gondwanaland. Stretching from Gujarat to Kanyakumari, it comprises the Konkan, Kanara, and Malabar coasts. Conversely, the Eastern Coastal Plain forms a broad, emergent margin shaped by marine regression and riverine sedimentation between the Eastern Ghats and the Bay of Bengal, divided into the Northern Circars and the Coromandel Coast. Offshore, the Bay of Bengal hosts the Andaman and Nicobar Islands—elevated crests of the submerged Arakan Yoma fold belt—while the Arabian Sea contains the Lakshadweep archipelago, comprising thirty-six coral atolls atop the Chagos-Laccadive submarine ridge.

Distinct geomorphological and hydrological mechanics govern these zones. High-velocity west-flowing rivers descend steep Western Ghats gradients, forming estuaries and natural harbors at Mumbai and Mormugao, while coastal deposition along the Malabar coast creates barrier bars and brackish lagoons termed kayals, particularly Vembanad and Ashtamudi. East-flowing rivers build prograding deltas along the Mahanadi, Godavari, Krishna, and Kaveri, bordering lagoons such as Chilika and Pulicat. Among oceanic territories, the Andaman and Nicobar chain is bisected by the Ten Degree Channel separating Little Andaman from Car Nicobar; it hosts Barren Island, South Asia's sole active volcano, and terminates south at Indira Point (6° 45′ N). Lakshadweep's atolls are partitioned by the Nine Degree Channel isolating Minicoy, and the Eight Degree Channel separating Minicoy from the Maldives.

These littoral and insular zones secure exclusive economic zone rights across two million square kilometers, governed under the Coastal Regulation Zone Notification of 2019 framed pursuant to the Environment (Protection) Act of 1986. For UPSC CSE and SSC examinations, this physical geography segment represents a high-frequency testing domain. Inquiries consistently evaluate maritime passage coordinates (such as the Ten Degree Channel and Duncan Passage), geomorphological differences between emergent and submergent coasts, Ramsar wetland sites like Vembanad and Chilika, indigenous tribal reserves of the Andaman archipelago (Jarawa, Sentinelese, and Shompen), and the strategic development of the Great Nicobar Transshipment Terminal.
Reviewed by the Master10 Editorial Board for accuracy, clarity and competitive-exam relevance.Editorial Policy

Key Concepts & Self-Assessment15 Key Facts

Review key Coastal Plains & Island Groups of India: Konkan to Andaman-Nicobar exam facts and rate your mastery to track revision.

Progress: 0/15 Rated 0 Mastered 0 Review Later
  1. #1
    The submerged Western Coastal Plain is subdivided into Konkan, Kanara, and Malabar coasts, featuring distinctive lagoon backwaters called kayals.
  2. #2
    The emergent Eastern Coastal Plain contains the Northern Circars and Coromandel Coast, accommodating extensive river deltas and Chilika Lake.
  3. #3
    The Andaman and Nicobar archipelago consists of elevated tectonic summits separated by the Ten Degree Channel at 10° N latitude.
  4. #4
    Barren Island in the Andaman Sea is the only active volcano in South Asia, while Saddle Peak is the archipelago's highest summit.
  5. #5
    Lakshadweep is a cluster of 36 coral atolls in the Arabian Sea, separated from Minicoy by the Nine Degree Channel and Maldives by the Eight Degree Channel.
  6. #6
    The Malabar Coast of Kerala features Vembanad Lake, India's longest wetland spanning 96 kilometres, designated as a Ramsar site in 2002.
  7. #7
    The Coromandel Coast receives substantial winter precipitation from October to December during the retreating Northeast monsoon season.
  8. #8
    Chilika Lake in Odisha is Asia's largest brackish water lagoon, separated from the Bay of Bengal by a 60-kilometre-long sandy barrier spit.
  9. #9
    Pulicat Lake, straddling Andhra Pradesh and Tamil Nadu, is India's second-largest brackish water lagoon, sheltered by the barrier island of Sriharikota.
  10. #10
    The Great Nicobar island contains Indira Point (6°45' N latitude), the southernmost point of Indian territory, submerged partially during the 2004 Indian Ocean tsunami.
  11. #11
    Narcondam Island in the northern Andaman Sea is a dormant volcanic island known for the endemic Narcondam hornbill.
  12. #12
    The Andaman archipelago is home to four indigenous Negrito tribal groups: the Great Andamanese, Onge, Jarawa, and the uncontacted Sentinelese.
  13. #13
    The Nicobar Islands are inhabited by two Mongoloid tribal communities: the Nicobarese and the nomadic Shompen hunters of Great Nicobar.
  14. #14
    Kavaratti functions as the administrative capital of Lakshadweep, where Pitti Island is declared a dedicated bird sanctuary under the Wildlife Protection Act.
  15. #15
    Pamban Island (Rameswaram) is linked to mainland Tamil Nadu across the Palk Strait by the historic 2-kilometre Pamban railway sea bridge constructed in 1914.

Subject Specialist Commentary

Analytical perspective & practical exam advice from the Master10 academic board

Educator's Insight
India's coastline features contrasting coastal plains and two major offshore island groups. The Western Coastal Plain is narrow and submerged, marked by natural ports, estuaries, and backwater lagoons known as kayals in Kerala. In contrast, the Eastern Coastal Plain is broad and emergent, defined by large river deltas and lakes like Chilika. Offshore, the volcanic Andaman and Nicobar archipelago in the Bay of Bengal contrasts with the Arabian Sea's Lakshadweep, an archipelago made entirely of coral atolls.
Maritime channels and coastal features are frequent scoring areas in UPSC and State PSC exams. Memorize the channel degrees: the Ten Degree Channel separates the Andaman and Nicobar Islands, while the Nine Degree Channel separates Minicoy from northern Lakshadweep. A common prelims trap involves rainfall: the Coromandel Coast receives most rainfall during winter from the retreating Northeast monsoon, unlike the western Malabar coast. In test revision, remember that Barren Island hosts South Asia's only active volcano.

Related Knowledge Topics to Discover

Indian Polity & Constitution
Indian Constitution & Fundamental Rights

Explore the Fundamental Rights guaranteed under Part III (Articles 12 to 35) of the Indian Constitution, constitutional remedies, and judicial safeguards.

Explore Topic
Indian Polity & Constitution
Supreme Court & Indian Judicial System

Learn how the Supreme Court of India functions, from original and appellate jurisdictions to judicial review, the collegium system, and basic structure.

Explore Topic
Indian Economy
National Income Accounting: GDP, GNP, NNP & GVA

Understand how national income is calculated in India, comparing GDP, GNP, NNP, and Gross Value Added at market prices and factor costs.

Explore Topic
Indian Geography
Duncan Passage

Explore the Duncan Passage in the Indian Ocean, examining the maritime strait separating South Andaman from Little Andaman and its navigation routes.

Explore Topic
Indian Geography
Ten Degree Channel

Learn about the Ten Degree Channel in the Bay of Bengal, exploring the 150-kilometer-wide marine passage separating the Andaman and Nicobar island groups.

Explore Topic
Indian Geography
Nine Degree Channel

Explore the Nine Degree Channel in the Arabian Sea, examining the shipping corridor that separates Minicoy Island from the central Lakshadweep atolls.

Explore Topic

Looking for more GK practice?

Explore 52,789+ questions across 65 General Knowledge categories.

Open Interactive Search