Abstract: The Heat Flow Study in the Tertiary Basin of Vietnam Offshore

Tran Huyen

In Vietnam, study of heat flow has paralleled petroleum exploration activities. For a long time there had only been results on temperature gradient in the Tertiary basin.

Recently, with its participation in CCOP's project on the establishment of heat flow regional maps (1992-1993) and the government's mineral resources program (1993-1995) (Coded KT-01-18), Vietnam Petroleum Institute's group on heat flow obtained results on heat flow. A heat flow study in the oil basinal area in Vietnam has been conducted using data from 76 exploratory wells. Thermal conductivity of 427 cores was measured using the quick thermal conductivity meter (QTM) within temperature gradient of wells being calculated from well log data and from testing data. The average heat flow of sedimentary basins in Vietnam follows: Hanoi graben, 125 Q (mW/m2); north Gulf of Tonkin, 87 Q (mW/m2; south Gulf of Tonkin, 119 Q (mW/m2); Danang Graben, 89 Q (mW/m2; northeast-south Conson, 88 Q (mW m2); southwest-south Conson, 85 Q (mW/m2); Mekong Basin, 64 Q (mW/m2).

In offshore Vietnam, the main phases of rifting and recent volcanic activity are the sources providing temperature for sedimentary basins. In the oil basin of Vietnam, thermal conductivity is closely related to the coarser and finer grained sediments and to the deep troughs.

The distribution pattern of the heat flow in the sedimentary basin is believed to be related to tectonic activity, structural history, recent volcanic activity, and maturity of hydrocarbon source rock. The heat flow value plays an important role in the study program for oil resources in Vietnam.

AAPG Search and Discovery Article #90982©1994 AAPG International Conference and Exhibition, Kuala Lumpur, Malaysia, August 21-24, 1994