With a Hydrogen to Carbon ratio of about 1.65 and lipids as the dominant compounds, name the type of kerogen.

• A. Type I
• B. Type II
• C. Type III
• D. Type IV

Answer: (A)

Kerogen types are distinguished by the hydrogen content and the origin of the organic matter. A hydrogen-to-carbon ratio around 1.65 with lipids dominating points to kerogen Type I, which is hydrogen-rich and derived from algal or aquatic sources rich in lipids. This composition yields high oil potential when mature. Types II, III, and IV are progressively less hydrogen-rich and differ in source material (marine in Type II, terrestrial in Type III, inert in Type IV) and lipid content, making Type I the best fit here.