Geology and development of geothermal field in Neogene Guantao Formation in northern Bohai Bay Basin: A case of the Caofeidian geothermal heating project in Tangshan, China

DONG Yuexia,HUANG Hongxiang,REN Lu,LI Hongda,DU Zhiqiang,E Junjie,WANG Qi,ZHANG Xiaoming

Table 1. Parameters of geothermal anomaly zones in the Nanpu sag and its surrounding areas.

No.	Geothermal anomaly zone	Thermal reservoir	Area/km²	Buried depth/m	Thermal reservoir thickness/m	Thermal reservoir temperature/°C	Geothermal gradient/(°C·(100 m)^-1)
I	Laowangzhuang- Xinanzhuang-Bagezhuang	Nm	310	1000-1300	140-160	45-55	3.2-4.2
		Ng	310	1100-1700	100-300	55-75	3.2-4.2
		O, —C	190	1400-2500	50-200	60-90	2.5-3.5
II	Laoyemiao- Gaoshangpu -Liuzan	Nm Ng	290	1700-2200 2100-2700	200-260 120-300	60-90 70-110	3.5-5.0
III	Nanpu	Nm Ng	667	1600-2400 2400-3 300	200-300 150-400	65-75 65-95	2.3-3.9
III	Nanpu	O, —C	101	>4000	100-200	150-200	3.0-4.0
IV	Matouying	Nm	174	1150-1400	150-160	70-105	4.0-7.0
		Ng	174	1350-1650	120-150	75-110	4.0-7.0
		Ar	145	1300-3000	1 500	150	1.8-2.5
V	Jiang Gezhuang	Nm	600	710-950	150-240	60-100	3.5-6.3
V	Jiang Gezhuang	Ng	600	950-1200	200-250	70-110	3.5-6.3