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Why can gaseous fuels allow an engine to use a higher compression ratio without knocking?

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Labeled cross-sectional diagram of a V-type gasoline engine for an automobile, showing internal components such as pistons, crankshaft, camshaft, intake and exhaust valves, connecting rods, spark plugs, and intake manifold. — gasoline engine Cross section of a V-type engine.

Gaseous fuels, such as natural gas or propane, generally possess better antiknock qualities than gasoline. This superior resistance to knocking—the premature, uncontrolled combustion of the air-fuel mixture—allows engines to operate at higher compression ratios without experiencing the damaging pressure waves or inefficient operation associated with knocking.12

In a standard internal-combustion engine, knocking occurs when high compression causes part of the fuel charge to ignite spontaneously before the flame front reaches it. Because gaseous fuels are more resistant to this premature detonation, they can withstand the increased heat and pressure of higher compression ratios more effectively than typical gasoline blends. While gasoline engines must be carefully formulated to balance volatility and antiknock quality to avoid these issues, the inherent properties of gaseous fuels provide a wider margin for performance optimization in this regard.123