{"id":22172,"date":"2026-10-03T21:53:50","date_gmt":"2026-10-03T16:23:50","guid":{"rendered":"https:\/\/geographynotespdf.com\/cms\/?p=22172"},"modified":"2026-10-04T09:20:49","modified_gmt":"2026-10-04T03:50:49","slug":"sea-floor-spreading-and-paleomagnetism","status":"publish","type":"post","link":"https:\/\/geographynotespdf.com\/cms\/sea-floor-spreading-and-paleomagnetism\/","title":{"rendered":"1. Sea-Floor Spreading and Paleomagnetism | \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u090f\u0935\u0902 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935"},"content":{"rendered":"\n\n\n
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Sea-Floor Spreading and Paleomagnetism\u00a0<\/strong><\/span><\/h2>\n

\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u090f\u0935\u0902 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935<\/strong><\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Introduction | \u092a\u0930\u093f\u091a\u092f<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0 \u00a0Sea-floor spreading<\/strong> and paleomagnetism<\/strong> are two important concepts that provided strong evidence for the development of the modern theory of Plate Tectonics<\/strong>. Sea-floor spreading explains the formation and outward movement of new oceanic crust from mid-oceanic ridges, while paleomagnetism provides evidence of the Earth’s past magnetic field and the movement of continents and oceanic plates.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 (Sea-Floor Spreading)<\/strong> \u0914\u0930 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 (Paleomagnetism)<\/strong> \u0906\u0927\u0941\u0928\u093f\u0915 \u092a\u094d\u0932\u0947\u091f \u0935\u093f\u0935\u0930\u094d\u0924\u0928\u093f\u0915\u0940 \u0938\u093f\u0926\u094d\u0927\u093e\u0902\u0924 (Plate Tectonic Theory)<\/strong> \u0915\u0947 \u0935\u093f\u0915\u093e\u0938 \u092e\u0947\u0902 \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u0905\u0935\u0927\u093e\u0930\u0923\u093e\u090f\u0901 \u0939\u0948\u0902\u0964 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u092f\u0939 \u0938\u092e\u091d\u093e\u0924\u093e \u0939\u0948 \u0915\u093f \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 (Mid-Oceanic Ridge) \u0915\u0947 \u0906\u0938\u092a\u093e\u0938 \u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0915\u0948\u0938\u0947 \u0939\u094b\u0924\u093e \u0939\u0948 \u0914\u0930 \u0935\u0939 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u092b\u0948\u0932\u0924\u0940 \u0939\u0948\u0964 \u0935\u0939\u0940\u0902 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u092a\u094d\u0930\u093e\u091a\u0940\u0928 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0924\u0925\u093e \u092e\u0939\u093e\u0926\u094d\u0935\u0940\u092a\u094b\u0902 \u090f\u0935\u0902 \u092a\u094d\u0932\u0947\u091f\u094b\u0902 \u0915\u0940 \u0917\u0924\u093f \u0915\u0947 \u092a\u094d\u0930\u092e\u093e\u0923 \u092a\u094d\u0930\u0926\u093e\u0928 \u0915\u0930\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

\n

Sea-Floor Spreading | \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0 The concept of Sea-Floor Spreading<\/strong> was proposed by Harry H. Hess in 1962<\/strong>. According to Hess, new oceanic crust is continuously formed along mid-oceanic ridges<\/strong> due to the upwelling of hot material from the mantle.<\/span><\/p>\n

The newly formed oceanic crust moves away from the ridge on both sides. As new material rises and solidifies at the ridge, it pushes the older oceanic crust farther away. Thus, the ocean floor continuously spreads outward from the ridge.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u0940 \u0905\u0935\u0927\u093e\u0930\u0923\u093e Harry H. Hess<\/span><\/strong> \u0928\u0947 1962 \u092e\u0947\u0902 \u092a\u094d\u0930\u0938\u094d\u0924\u0941\u0924 \u0915\u0940\u0964 \u0909\u0928\u0915\u0947 \u0905\u0928\u0941\u0938\u093e\u0930 \u092e\u0948\u0902\u091f\u0932 (Mantle) \u0938\u0947 \u0917\u0930\u094d\u092e \u092a\u0926\u093e\u0930\u094d\u0925 \u0915\u0947 \u090a\u092a\u0930 \u0909\u0920\u0928\u0947 \u0915\u0947 \u0915\u093e\u0930\u0923 \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 (Mid-Oceanic Ridges)<\/span><\/strong> \u092a\u0930 \u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0939\u094b\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

\u0928\u0935 \u0928\u093f\u0930\u094d\u092e\u093f\u0924 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u091f\u0915 \u0915\u0947 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u0926\u0942\u0930 \u0939\u094b\u0924\u0940 \u091c\u093e\u0924\u0940 \u0939\u0948\u0964 \u0915\u091f\u0915 \u092a\u0930 \u0932\u0917\u093e\u0924\u093e\u0930 \u0928\u092f\u093e \u092a\u0926\u093e\u0930\u094d\u0925 \u090a\u092a\u0930 \u0906\u0924\u093e \u0939\u0948 \u0914\u0930 \u0920\u0902\u0921\u093e \u0939\u094b\u0915\u0930 \u0928\u0908 \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u092c\u0928\u093e\u0924\u093e \u0939\u0948\u0964 \u0907\u0938\u0938\u0947 \u092a\u0941\u0930\u093e\u0928\u0940 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u091f\u0915 \u0938\u0947 \u0926\u0942\u0930 \u0927\u0915\u0947\u0932\u0940 \u091c\u093e\u0924\u0940 \u0939\u0948\u0964 \u0907\u0938\u0940 \u092a\u094d\u0930\u0915\u094d\u0930\u093f\u092f\u093e \u0915\u094b \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923<\/strong><\/span> \u0915\u0939\u093e \u091c\u093e\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

Mechanism of Sea-Floor Spreading<\/span><\/strong><\/span><\/p>\n

\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u0940 \u092a\u094d\u0930\u0915\u094d\u0930\u093f\u092f\u093e<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u0907\u0938 \u092a\u094d\u0930\u0915\u094d\u0930\u093f\u092f\u093e \u0915\u094b \u0928\u093f\u092e\u094d\u0928 \u0915\u094d\u0930\u092e \u092e\u0947\u0902 \u0938\u092e\u091d\u093e \u091c\u093e \u0938\u0915\u0924\u093e \u0939\u0948:<\/span><\/p>\n

Mantle Upwelling\/\u092e\u0948\u0902\u091f\u0932 \u0938\u0947 \u0917\u0930\u094d\u092e \u092a\u0926\u093e\u0930\u094d\u0925 \u0915\u093e \u090a\u092a\u0930 \u0909\u0920\u0928\u093e<\/strong><\/span>
\n\u2193<\/span>
\nMagma rises through the ridge\/\u0915\u091f\u0915 \u0915\u0947 \u092e\u0927\u094d\u092f \u0938\u0947 \u092e\u0948\u0917\u094d\u092e\u093e \u0915\u093e \u090a\u092a\u0930 \u0906\u0928\u093e<\/strong><\/span>
\n\u2193<\/span>
\nCooling and solidification\/\u092e\u0948\u0917\u094d\u092e\u093e \u0915\u093e \u0920\u0902\u0921\u093e \u0939\u094b\u0915\u0930 \u0920\u094b\u0938 \u0939\u094b\u0928\u093e<\/strong><\/span>
\n\u2193<\/span>
\nFormation of new oceanic crust\/\u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923<\/strong><\/span>
\n\u2193<\/span>
\nMovement away from the ridge\/\u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0915\u091f\u0915 \u0938\u0947 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u0926\u0942\u0930 \u091c\u093e\u0928\u093e<\/strong><\/span>
\n\u2193<\/span>
\nSea-floor spreading\/\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u0915\u093e \u092a\u094d\u0930\u0938\u0930\u0923<\/strong><\/span><\/p>\n

Evidence of Sea-Floor Spreading<\/span><\/strong><\/p>\n

\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u0947 \u092a\u094d\u0930\u092e\u093e\u0923<\/span><\/strong><\/p>\n

\u00a0 \u00a0 \u00a0Sea-floor spreading is supported by several important pieces of evidence.<\/span><\/p>\n

(i) Mid-Oceanic Ridges | \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 The global system of mid-oceanic ridges is associated with volcanic activity and the formation of new oceanic crust. \u0935\u093f\u0936\u094d\u0935 \u0915\u0947 \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u0924\u0902\u0924\u094d\u0930 \u0915\u0947 \u0906\u0938\u092a\u093e\u0938 \u091c\u094d\u0935\u093e\u0932\u093e\u092e\u0941\u0916\u0940\u092f \u0917\u0924\u093f\u0935\u093f\u0927\u093f\u092f\u093e\u0901 \u0939\u094b\u0924\u0940 \u0939\u0948\u0902 \u0924\u0925\u093e \u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0939\u094b\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

(ii) Age of Oceanic Crust | \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u0940 \u0906\u092f\u0941<\/span><\/strong><\/p>\n

\u00a0 \u00a0 The rocks near the mid-oceanic ridge are generally younger, while rocks become progressively older away from the ridge. \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u0915\u0947 \u0928\u093f\u0915\u091f \u092a\u093e\u0908 \u091c\u093e\u0928\u0947 \u0935\u093e\u0932\u0940 \u091a\u091f\u094d\u091f\u093e\u0928\u0947\u0902 \u0905\u092a\u0947\u0915\u094d\u0937\u093e\u0915\u0943\u0924 \u0928\u0908<\/strong> \u0939\u094b\u0924\u0940 \u0939\u0948\u0902, \u091c\u092c\u0915\u093f \u0915\u091f\u0915 \u0938\u0947 \u0926\u0942\u0930 \u091c\u093e\u0928\u0947 \u092a\u0930 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u091a\u091f\u094d\u091f\u093e\u0928\u094b\u0902 \u0915\u0940 \u0906\u092f\u0941 \u092c\u0922\u093c\u0924\u0940 \u091c\u093e\u0924\u0940 \u0939\u0948\u0964<\/span><\/p>\n

\u092f\u0939 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u0915\u0947 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u093e \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u092a\u094d\u0930\u092e\u093e\u0923 \u0939\u0948\u0964<\/span><\/p>\n

(iii) Sediment Thickness | \u0905\u0935\u0938\u093e\u0926 \u0915\u0940 \u092e\u094b\u091f\u093e\u0908<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 Sediments are generally thinner near the mid-oceanic ridge and become thicker with increasing distance from the ridge. \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u0915\u0947 \u092a\u093e\u0938 \u0938\u092e\u0941\u0926\u094d\u0930\u0940 \u0905\u0935\u0938\u093e\u0926\u094b\u0902 \u0915\u0940 \u092e\u094b\u091f\u093e\u0908 \u0915\u092e \u0939\u094b\u0924\u0940 \u0939\u0948\u0964 \u0915\u091f\u0915 \u0938\u0947 \u0926\u0942\u0930 \u091c\u093e\u0928\u0947 \u092a\u0930 \u0905\u0935\u0938\u093e\u0926\u094b\u0902 \u0915\u0940 \u092e\u094b\u091f\u093e\u0908 \u0938\u093e\u092e\u093e\u0928\u094d\u092f\u0924\u0903 \u092c\u0922\u093c\u0924\u0940 \u091c\u093e\u0924\u0940 \u0939\u0948\u0964<\/span><\/p>\n

\u0907\u0938\u0938\u0947 \u0938\u0902\u0915\u0947\u0924 \u092e\u093f\u0932\u0924\u093e \u0939\u0948 \u0915\u093f \u0915\u091f\u0915 \u0915\u0947 \u092a\u093e\u0938 \u0928\u0908 \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0939\u094b\u0924\u093e \u0930\u0939\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

(iv) Symmetrical Magnetic Stripes | \u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u093e\u0901<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 One of the strongest pieces of evidence came from the discovery of symmetrical magnetic anomalies on both sides of mid-oceanic ridges. \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u0930 \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u0915\u0947 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u094b\u0902 (Symmetrical Magnetic Stripes)<\/strong> \u0915\u093e \u092a\u093e\u092f\u093e \u091c\u093e\u0928\u093e \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u093e \u0905\u0924\u094d\u092f\u0902\u0924 \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u092a\u094d\u0930\u092e\u093e\u0923 \u0939\u0948\u0964<\/span><\/p>\n

Paleomagnetism | \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0Paleomagnetism<\/strong> is the study of the ancient magnetic field of the Earth as recorded in rocks.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0When volcanic rocks containing magnetic minerals such as magnetite<\/strong> cool below their Curie temperature (\u0932\u0917\u092d\u0917 580\u00b0C)<\/strong>, these minerals can preserve the direction of the Earth’s magnetic field existing at that time.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0\u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 (Paleomagnetism)<\/strong> \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u092a\u094d\u0930\u093e\u091a\u0940\u0928 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0947 \u0905\u0927\u094d\u092f\u092f\u0928 \u0915\u094b \u0915\u0939\u0924\u0947 \u0939\u0948\u0902, \u091c\u093f\u0938\u0915\u093e \u092a\u094d\u0930\u092e\u093e\u0923 \u091a\u091f\u094d\u091f\u093e\u0928\u094b\u0902 \u092e\u0947\u0902 \u0938\u0902\u0930\u0915\u094d\u0937\u093f\u0924 \u0930\u0939\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u091c\u094d\u0935\u093e\u0932\u093e\u092e\u0941\u0916\u0940\u092f \u091a\u091f\u094d\u091f\u093e\u0928\u094b\u0902 \u092e\u0947\u0902 \u092a\u093e\u090f \u091c\u093e\u0928\u0947 \u0935\u093e\u0932\u0947 \u092e\u0948\u0917\u094d\u0928\u0947\u091f\u093e\u0907\u091f (Magnetite)<\/strong> \u091c\u0948\u0938\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0916\u0928\u093f\u091c \u091c\u092c \u0905\u092a\u0928\u0947 \u0915\u094d\u092f\u0942\u0930\u0940 \u0924\u093e\u092a\u092e\u093e\u0928 (Curie Temperature)<\/strong> \u0938\u0947 \u0928\u0940\u091a\u0947 \u0920\u0902\u0921\u0947 \u0939\u094b\u0924\u0947 \u0939\u0948\u0902, \u0924\u094b \u0909\u0938 \u0938\u092e\u092f \u0915\u0947 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0940 \u0926\u093f\u0936\u093e \u0914\u0930 \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e \u0915\u093e \u0905\u092d\u093f\u0932\u0947\u0916 \u0909\u0928\u092e\u0947\u0902 \u0938\u0941\u0930\u0915\u094d\u0937\u093f\u0924 \u0939\u094b \u0938\u0915\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

Earth’s Magnetic Reversals<\/span><\/strong><\/p>\n

\u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u094d\u0930\u0941\u0935 \u092a\u0930\u093f\u0935\u0930\u094d\u0924\u0928<\/span><\/strong><\/p>\n

\u00a0 \u00a0 \u00a0The Earth’s magnetic field has not remained constant throughout geological history. It has periodically undergone magnetic reversals<\/strong>, during which the magnetic north and south poles effectively exchange positions.<\/span><\/p>\n

Two basic magnetic states are commonly identified:<\/span><\/p>\n

✍️ <\/span><\/span>Normal Polarity<\/strong> – magnetic field broadly similar to the present orientation.<\/span><\/p>\n

✍️ <\/span><\/span>Reversed Polarity<\/strong> – magnetic field orientation opposite to the present one.<\/span><\/p>\n

\u00a0 \u00a0 \u092d\u0942\u0935\u0948\u091c\u094d\u091e\u093e\u0928\u093f\u0915 \u0907\u0924\u093f\u0939\u093e\u0938 \u092e\u0947\u0902 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u093e \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0939\u092e\u0947\u0936\u093e \u090f\u0915 \u091c\u0948\u0938\u093e \u0928\u0939\u0940\u0902 \u0930\u0939\u093e \u0939\u0948\u0964 \u0938\u092e\u092f-\u0938\u092e\u092f \u092a\u0930 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u094d\u0930\u0941\u0935\u094b\u0902 \u092e\u0947\u0902 \u0909\u0932\u091f\u092b\u0947\u0930 (Magnetic Reversal)<\/strong> \u0939\u0941\u0906 \u0939\u0948\u0964<\/span><\/p>\n

\u092e\u0941\u0916\u094d\u092f\u0924\u0903 \u0926\u094b \u092a\u094d\u0930\u0915\u093e\u0930 \u0915\u0940 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e \u0915\u094b \u0938\u092e\u091d\u093e \u091c\u093e\u0924\u093e \u0939\u0948:<\/span><\/p>\n

✍️ <\/span><\/span>\u0938\u093e\u092e\u093e\u0928\u094d\u092f \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e (Normal Polarity)<\/strong> – \u0935\u0930\u094d\u0924\u092e\u093e\u0928 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0947 \u0938\u092e\u093e\u0928 \u0905\u092d\u093f\u0935\u093f\u0928\u094d\u092f\u093e\u0938\u0964<\/span><\/p>\n

✍️ <\/span><\/span>\u0935\u093f\u092a\u0930\u0940\u0924 \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e (Reversed Polarity)<\/strong> – \u0935\u0930\u094d\u0924\u092e\u093e\u0928 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0947 \u0935\u093f\u092a\u0930\u0940\u0924 \u0905\u092d\u093f\u0935\u093f\u0928\u094d\u092f\u093e\u0938\u0964<\/span><\/p>\n

Paleomagnetism and Sea-Floor Spreading<\/strong><\/span><\/p>\n

\u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 \u090f\u0935\u0902 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>\u092f\u0939 \u0926\u094b\u0928\u094b\u0902 \u0905\u0935\u0927\u093e\u0930\u0923\u093e\u090f\u0901 \u090f\u0915-\u0926\u0942\u0938\u0930\u0947 \u0938\u0947 \u0917\u0939\u0930\u093e\u0908 \u0938\u0947 \u091c\u0941\u0921\u093c\u0940 \u0939\u0948\u0902\u0964<\/span><\/p>\n

✍️ <\/span><\/span>\u091c\u092c \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u092a\u0930 \u0928\u092f\u093e \u092c\u0947\u0938\u093e\u0932\u094d\u091f\u093f\u0915 \u092a\u0926\u093e\u0930\u094d\u0925 \u0920\u0902\u0921\u093e \u0939\u094b\u0924\u093e \u0939\u0948, \u0924\u094b \u0909\u0938\u092e\u0947\u0902 \u0909\u092a\u0938\u094d\u0925\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0916\u0928\u093f\u091c \u0909\u0938 \u0938\u092e\u092f \u0915\u0947 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0940 \u0926\u093f\u0936\u093e \u0915\u094b \u0930\u093f\u0915\u0949\u0930\u094d\u0921 \u0915\u0930 \u0932\u0947\u0924\u0947 \u0939\u0948\u0902\u0964<\/span><\/p>\n

✍️ <\/span><\/span>\u092c\u093e\u0926 \u092e\u0947\u0902 \u091c\u092c \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0940 \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e \u092c\u0926\u0932\u0924\u0940 \u0939\u0948 \u0914\u0930 \u0928\u0908 \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u092c\u0928\u0924\u0940 \u0939\u0948, \u0924\u094b \u0928\u0908 \u091a\u091f\u094d\u091f\u093e\u0928\u094b\u0902 \u092e\u0947\u0902 \u0935\u093f\u092a\u0930\u0940\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0926\u093f\u0936\u093e \u0926\u0930\u094d\u091c \u0939\u094b \u091c\u093e\u0924\u0940 \u0939\u0948\u0964<\/span><\/p>\n

\u00a0 \u00a0 \u0907\u0938 \u092a\u094d\u0930\u0915\u093e\u0930 \u0915\u091f\u0915 \u0915\u0947 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930:<\/span><\/p>\n

Normal<\/a> \u2192 Reversed<\/a> \u2192 Normal \u2192 Reversed <\/strong>\u091c\u0948\u0938\u0940 \u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u093e\u0901<\/strong> \u0935\u093f\u0915\u0938\u093f\u0924 \u0939\u094b\u0924\u0940 \u0939\u0948\u0902\u0964<\/span><\/p>\n

Symmetrical Magnetic Stripes<\/strong><\/span><\/p>\n

\u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u093e\u0901<\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0 The symmetrical pattern of magnetic anomalies on either side of a mid-ocean ridge is one of the most convincing pieces of evidence for sea-floor spreading.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0The pattern records successive periods of normal and reversed geomagnetic polarity. Because new crust forms at the ridge and moves outward in both directions, the magnetic pattern is approximately symmetrical on the two sides.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u0915\u0947 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u092a\u093e\u0908 \u091c\u093e\u0928\u0947 \u0935\u093e\u0932\u0940 \u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u093e\u0901<\/strong> \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u093e \u0905\u0924\u094d\u092f\u0902\u0924 \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u092a\u094d\u0930\u092e\u093e\u0923 \u0939\u0948\u0902\u0964<\/span><\/p>\n

\u00a0 \u00a0 \u00a0\u0907\u0928 \u0927\u093e\u0930\u093f\u092f\u094b\u0902 \u092e\u0947\u0902 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0940 \u0935\u093f\u092d\u093f\u0928\u094d\u0928 \u0905\u0935\u0927\u093f\u092f\u094b\u0902 \u0915\u0940 \u0938\u093e\u092e\u093e\u0928\u094d\u092f \u0914\u0930 \u0935\u093f\u092a\u0930\u0940\u0924 \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e<\/strong> \u0915\u093e \u0930\u093f\u0915\u0949\u0930\u094d\u0921 \u092e\u093f\u0932\u0924\u093e \u0939\u0948\u0964 \u0915\u091f\u0915 \u092a\u0930 \u0928\u0908 \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u092c\u0928\u0928\u0947 \u0915\u0947 \u092c\u093e\u0926 \u0935\u0939 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u0938\u092e\u093e\u0928 \u0930\u0942\u092a \u0938\u0947 \u0926\u0942\u0930 \u091c\u093e\u0924\u0940 \u0939\u0948, \u0907\u0938\u0932\u093f\u090f \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u094b\u0902 \u0915\u093e \u092a\u0948\u091f\u0930\u094d\u0928 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u0932\u0917\u092d\u0917 \u0938\u092e\u092e\u093f\u0924 \u0926\u093f\u0916\u093e\u0908 \u0926\u0947\u0924\u093e \u0939\u0948\u0964<\/span><\/p>\n

\"\"<\/p>\n

Vine\u2013Matthews Hypothesis<\/strong><\/span><\/p>\n

\u0935\u093e\u0907\u0928-\u092e\u0948\u0925\u094d\u092f\u0942\u091c \u092a\u0930\u093f\u0915\u0932\u094d\u092a\u0928\u093e<\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0In 1963<\/strong>, Frederick Vine and Drummond Matthews<\/strong> proposed an explanation linking magnetic anomalies on the ocean floor with sea-floor spreading and geomagnetic reversals.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0They argued that newly formed basalt at mid-ocean ridges records the Earth’s magnetic polarity as it cools. As the sea floor spreads, these records are carried away from the ridge, producing symmetrical magnetic patterns.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a01963 \u092e\u0947\u0902 Frederick Vine \u0914\u0930 Drummond Matthews<\/strong> \u0928\u0947 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u0930 \u092a\u093e\u0908 \u091c\u093e\u0928\u0947 \u0935\u093e\u0932\u0940 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0935\u093f\u0938\u0902\u0917\u0924\u093f\u092f\u094b\u0902 (Magnetic Anomalies) \u0915\u094b \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0914\u0930 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u094d\u0930\u0941\u0935 \u092a\u0930\u093f\u0935\u0930\u094d\u0924\u0928\u094b\u0902 \u0938\u0947 \u091c\u094b\u0921\u093c\u0915\u0930 \u0938\u092e\u091d\u093e\u092f\u093e\u0964<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0\u0909\u0928\u0915\u0947 \u0905\u0928\u0941\u0938\u093e\u0930 \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u092a\u0930 \u092c\u0928\u0928\u0947 \u0935\u093e\u0932\u093e \u0928\u092f\u093e \u092c\u0947\u0938\u093e\u0932\u094d\u091f \u0920\u0902\u0921\u093e \u0939\u094b\u0924\u0947 \u0938\u092e\u092f \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0940 \u0924\u0924\u094d\u0915\u093e\u0932\u0940\u0928 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e \u0915\u094b \u0930\u093f\u0915\u0949\u0930\u094d\u0921 \u0915\u0930\u0924\u093e \u0939\u0948\u0964 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u0915\u0947 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u0947 \u0938\u093e\u0925 \u092f\u0947 \u091a\u091f\u094d\u091f\u093e\u0928\u0947\u0902 \u0915\u091f\u0915 \u0938\u0947 \u0926\u0942\u0930 \u091a\u0932\u0940 \u091c\u093e\u0924\u0940 \u0939\u0948\u0902 \u0914\u0930 \u0907\u0938 \u092a\u094d\u0930\u0915\u093e\u0930 \u0926\u094b\u0928\u094b\u0902 \u0913\u0930 \u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u093e\u0901 \u092c\u0928\u0924\u0940 \u0939\u0948\u0902\u0964<\/span><\/p>\n

Importance of Paleomagnetism<\/span><\/strong><\/span><\/p>\n

\u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 \u0915\u093e \u092e\u0939\u0924\u094d\u0935<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0Paleomagnetism has helped scientists to\/\u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 \u0928\u0947 \u0935\u0948\u091c\u094d\u091e\u093e\u0928\u093f\u0915\u094b\u0902 \u0915\u094b \u0928\u093f\u092e\u094d\u0928\u0932\u093f\u0916\u093f\u0924 \u0938\u092e\u091d\u0928\u0947 \u092e\u0947\u0902 \u0938\u0939\u093e\u092f\u0924\u093e \u0915\u0940 \u0939\u0948:<\/span><\/p>\n

✍️ <\/span><\/span>Establish evidence for sea-floor spreading. \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u0947 \u092a\u094d\u0930\u092e\u093e\u0923 \u092a\u094d\u0930\u093e\u092a\u094d\u0924 \u0915\u0930\u0928\u093e\u0964<\/span><\/p>\n

✍️ <\/span><\/span>Understand geomagnetic reversals. \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u094d\u0930\u0941\u0935 \u092a\u0930\u093f\u0935\u0930\u094d\u0924\u0928\u094b\u0902 \u0915\u094b \u0938\u092e\u091d\u0928\u093e\u0964<\/span><\/p>\n

✍️ <\/span><\/span>Reconstruct the past positions of continents. \u092e\u0939\u093e\u0926\u094d\u0935\u0940\u092a\u094b\u0902 \u0915\u0940 \u092a\u094d\u0930\u093e\u091a\u0940\u0928 \u0905\u0935\u0938\u094d\u0925\u093f\u0924\u093f \u0915\u093e \u092a\u0941\u0928\u0930\u094d\u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0915\u0930\u0928\u093e\u0964<\/span><\/p>\n

✍️ <\/span><\/span>Study the movement of tectonic plates. \u091f\u0947\u0915\u094d\u091f\u094b\u0928\u093f\u0915 \u092a\u094d\u0932\u0947\u091f\u094b\u0902 \u0915\u0940 \u0917\u0924\u093f \u0915\u093e \u0905\u0927\u094d\u092f\u092f\u0928 \u0915\u0930\u0928\u093e\u0964<\/span><\/p>\n

✍️ <\/span><\/span>Support the theory of plate tectonics. \u092a\u094d\u0932\u0947\u091f \u0935\u093f\u0935\u0930\u094d\u0924\u0928\u093f\u0915\u0940 \u0938\u093f\u0926\u094d\u0927\u093e\u0902\u0924 \u0915\u094b \u092a\u094d\u0930\u092e\u093e\u0923\u093f\u0924 \u0915\u0930\u0928\u0947 \u092e\u0947\u0902 \u0938\u0939\u093e\u092f\u0924\u093e \u0915\u0930\u0928\u093e\u0964<\/span><\/p>\n

✍️ <\/span><\/span>Estimate the age of oceanic crust. \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u0940 \u0906\u092f\u0941 \u0915\u093e \u0905\u0928\u0941\u092e\u093e\u0928 \u0932\u0917\u093e\u0928\u093e\u0964<\/span><\/p>\n

✍️ <\/span><\/span>Reconstruct past geographic conditions. \u092a\u094d\u0930\u093e\u091a\u0940\u0928 \u092d\u094c\u0917\u094b\u0932\u093f\u0915 \u092a\u0930\u093f\u0938\u094d\u0925\u093f\u0924\u093f\u092f\u094b\u0902 \u0915\u093e \u092a\u0941\u0928\u0930\u094d\u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0915\u0930\u0928\u093e\u0964<\/span><\/p>\n

Sea-Floor Spreading vs Paleomagnetism<\/strong><\/span><\/p>\n

\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u090f\u0935\u0902 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 \u092e\u0947\u0902 \u0905\u0902\u0924\u0930<\/strong><\/span><\/p>\n\n\n\n\n\n\n\n\n\n
\u0906\u0927\u093e\u0930<\/span><\/td>\nSea-Floor Spreading<\/span><\/td>\nPaleomagnetism<\/span><\/td>\n<\/tr>\n
\u0905\u0930\u094d\u0925<\/span><\/td>\n\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u0915\u0940 \u0928\u0908 \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u090f\u0935\u0902 \u092a\u094d\u0930\u0938\u0930\u0923<\/span><\/td>\n\u092a\u094d\u0930\u093e\u091a\u0940\u0928 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u093e \u0905\u0927\u094d\u092f\u092f\u0928<\/span><\/td>\n<\/tr>\n
\u092a\u094d\u0930\u092e\u0941\u0916 \u0935\u0948\u091c\u094d\u091e\u093e\u0928\u093f\u0915<\/span><\/td>\nHarry H. Hess<\/span><\/td>\nVine & Matthews \u0928\u0947 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u092a\u0948\u091f\u0930\u094d\u0928 \u0915\u0940 \u0935\u094d\u092f\u093e\u0916\u094d\u092f\u093e \u0915\u0940<\/span><\/td>\n<\/tr>\n
\u092e\u0941\u0916\u094d\u092f \u0906\u0927\u093e\u0930<\/span><\/td>\nMid-Oceanic Ridges<\/span><\/td>\nMagnetic minerals<\/span><\/td>\n<\/tr>\n
\u092a\u094d\u0930\u092e\u0941\u0916 \u092a\u094d\u0930\u092e\u093e\u0923<\/span><\/td>\n\u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940<\/span><\/td>\nMagnetic stripes<\/span><\/td>\n<\/tr>\n
\u092e\u0941\u0916\u094d\u092f \u092a\u094d\u0930\u0915\u094d\u0930\u093f\u092f\u093e<\/span><\/td>\n\u0928\u0908 crust \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0914\u0930 outward movement<\/span><\/td>\nMagnetic polarity \u0915\u093e rock record<\/span><\/td>\n<\/tr>\n
\u092e\u0939\u0924\u094d\u0935<\/span><\/td>\nOceanic crust formation \u0915\u094b \u0938\u092e\u091d\u093e\u0924\u093e \u0939\u0948<\/span><\/td>\nSea-floor spreading \u090f\u0935\u0902 plate movement \u0915\u0947 \u092a\u094d\u0930\u092e\u093e\u0923 \u0926\u0947\u0924\u093e \u0939\u0948<\/span><\/td>\n<\/tr>\n<\/tbody>\n<\/table>\n

Significance in Plate Tectonic Theory<\/span><\/strong><\/span><\/p>\n

\u092a\u094d\u0932\u0947\u091f \u0935\u093f\u0935\u0930\u094d\u0924\u0928\u093f\u0915\u0940 \u0938\u093f\u0926\u094d\u0927\u093e\u0902\u0924 \u092e\u0947\u0902 \u092e\u0939\u0924\u094d\u0935<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u00a0Sea-floor spreading and paleomagnetism together provided strong support for the modern theory of plate tectonics. Sea-floor spreading explains how new oceanic lithosphere is generated, while paleomagnetic evidence demonstrates that this crust records successive reversals of Earth’s magnetic field and moves away from mid-ocean ridges.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0\u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0914\u0930 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935<\/strong> \u0928\u0947 \u0906\u0927\u0941\u0928\u093f\u0915 \u092a\u094d\u0932\u0947\u091f \u0935\u093f\u0935\u0930\u094d\u0924\u0928\u093f\u0915\u0940 \u0938\u093f\u0926\u094d\u0927\u093e\u0902\u0924<\/strong> \u0915\u094b \u092e\u091c\u092c\u0942\u0924 \u0935\u0948\u091c\u094d\u091e\u093e\u0928\u093f\u0915 \u0906\u0927\u093e\u0930 \u092a\u094d\u0930\u0926\u093e\u0928 \u0915\u093f\u092f\u093e\u0964 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u092f\u0939 \u0938\u094d\u092a\u0937\u094d\u091f \u0915\u0930\u0924\u093e \u0939\u0948 \u0915\u093f \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u092a\u0930 \u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0938\u094d\u0925\u0932\u092e\u0902\u0921\u0932\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923 \u0915\u0948\u0938\u0947 \u0939\u094b\u0924\u093e \u0939\u0948, \u091c\u092c\u0915\u093f \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0940\u092f \u092a\u094d\u0930\u092e\u093e\u0923 \u092c\u0924\u093e\u0924\u0947 \u0939\u0948\u0902 \u0915\u093f \u092f\u0939 \u0928\u0908 \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u092a\u0943\u0925\u094d\u0935\u0940 \u0915\u0947 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0915\u094d\u0937\u0947\u0924\u094d\u0930 \u0915\u0940 \u0915\u094d\u0930\u092e\u093f\u0915 \u0927\u094d\u0930\u0941\u0935\u0940\u092f\u0924\u093e \u0915\u094b \u0930\u093f\u0915\u0949\u0930\u094d\u0921 \u0915\u0930\u0924\u0940 \u0939\u0941\u0908 \u0915\u091f\u0915 \u0938\u0947 \u0926\u0942\u0930 \u091c\u093e\u0924\u0940 \u0939\u0948\u0964<\/span><\/p>\n

Conclusion | \u0928\u093f\u0937\u094d\u0915\u0930\u094d\u0937<\/span><\/strong><\/span><\/p>\n

\u00a0 \u00a0 \u00a0Sea-floor spreading and paleomagnetism represent two closely connected developments in modern Earth science. The formation of new oceanic crust at mid-ocean ridges, its increasing age away from the ridge, and the symmetrical pattern of magnetic anomalies provide important evidence for the spreading of the ocean floor. Together, these observations played a major role in establishing the modern plate tectonic framework.<\/span><\/p>\n

\u00a0 \u00a0 \u00a0 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0914\u0930 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 \u0906\u0927\u0941\u0928\u093f\u0915 \u092d\u0942-\u0935\u093f\u091c\u094d\u091e\u093e\u0928 \u0915\u0940 \u0926\u094b \u092a\u0930\u0938\u094d\u092a\u0930 \u0938\u0902\u092c\u0902\u0927\u093f\u0924 \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u0905\u0935\u0927\u093e\u0930\u0923\u093e\u090f\u0901 \u0939\u0948\u0902\u0964 \u092e\u0927\u094d\u092f-\u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u0915\u091f\u0915 \u092a\u0930 \u0928\u0908 \u092e\u0939\u093e\u0938\u093e\u0917\u0930\u0940\u092f \u092d\u0942\u092a\u0930\u094d\u092a\u091f\u0940 \u0915\u093e \u0928\u093f\u0930\u094d\u092e\u093e\u0923, \u0915\u091f\u0915 \u0938\u0947 \u0926\u0942\u0930 \u091c\u093e\u0928\u0947 \u092a\u0930 \u091a\u091f\u094d\u091f\u093e\u0928\u094b\u0902 \u0915\u0940 \u092c\u0922\u093c\u0924\u0940 \u0906\u092f\u0941 \u0924\u0925\u093e \u0938\u092e\u092e\u093f\u0924 \u091a\u0941\u0902\u092c\u0915\u0940\u092f \u0927\u093e\u0930\u093f\u092f\u093e\u0901 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u0915\u0947 \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u092a\u094d\u0930\u092e\u093e\u0923 \u0939\u0948\u0902\u0964 \u0907\u0928 \u092a\u094d\u0930\u092e\u093e\u0923\u094b\u0902 \u0928\u0947 \u0906\u0927\u0941\u0928\u093f\u0915 \u092a\u094d\u0932\u0947\u091f \u0935\u093f\u0935\u0930\u094d\u0924\u0928\u093f\u0915\u0940 \u0938\u093f\u0926\u094d\u0927\u093e\u0902\u0924<\/strong><\/span> \u0915\u0947 \u0935\u093f\u0915\u093e\u0938 \u0914\u0930 \u0938\u094d\u0925\u093e\u092a\u0928\u093e \u092e\u0947\u0902 \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u092d\u0942\u092e\u093f\u0915\u093e \u0928\u093f\u092d\u093e\u0908\u0964<\/span><\/p>\n

Quick Revision | \u0924\u094d\u0935\u0930\u093f\u0924 \u092a\u0941\u0928\u0930\u093e\u0935\u0943\u0924\u094d\u0924\u093f<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Hess (1962) \u2192 Sea-Floor Spreading<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Vine & Matthews (1963) \u2192 Magnetic stripes \u0915\u0940 \u0935\u094d\u092f\u093e\u0916\u094d\u092f\u093e<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Mid-Oceanic Ridge \u2192 New oceanic crust<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Magnetite \u2192 Magnetic record<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Normal + Reversed Polarity \u2192 Magnetic stripes<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Symmetrical Magnetic Stripes \u2192 Strong evidence of Sea-Floor Spreading<\/strong><\/span><\/p>\n

✍️ <\/span><\/span>Sea-Floor Spreading + Paleomagnetism \u2192 Plate Tectonic Theory \u0915\u093e \u092e\u0939\u0924\u094d\u0935\u092a\u0942\u0930\u094d\u0923 \u0906\u0927\u093e\u0930<\/strong><\/span><\/p>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Sea-Floor Spreading and Paleomagnetism\u00a0 \u0938\u092e\u0941\u0926\u094d\u0930-\u0924\u0932 \u092a\u094d\u0930\u0938\u0930\u0923 \u090f\u0935\u0902 \u092a\u0941\u0930\u093e\u091a\u0941\u092e\u094d\u092c\u0915\u0924\u094d\u0935 Introduction | \u092a\u0930\u093f\u091a\u092f \u00a0 \u00a0 \u00a0 \u00a0 \u00a0Sea-floor spreading and paleomagnetism are two important concepts that provided strong evidence for the development of the modern theory of Plate Tectonics. Sea-floor spreading explains the formation and outward movement of new oceanic crust from mid-oceanic ridges, while paleomagnetism provides 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