Neogene Geothermal Resources Evaluation In Hashu Lake Inner Mongolia

According to the previous geothermal exploration results, there are four types ofgeotherrnal reservoir in Huhe Depression Basin,ircluding,Mount Daqing piedmont faultzone reservoir, the deep Pacific-Proterozoic marble reservoir, the Jurassic Cretaceousglutenite reservoir and the Neogene reservoir. well HR1(completed in1999) The maingeotherrnal reservoir exposed is Proterozoic and the Jurassic cretaceous stratum.HR2well (completed in1999)main heat reservoir exposed is Cretaceous and the Archaeozoicstratum.The two wells in the reservoir bottom boundary depth is up to3000m. The welldepth is more than3000m and, construction is cost and difficult. Hasuhai HR3geothermal well was completed in2009-2010.The depth of the borehole is3368.95m.According to HR1, HR2geothermal exploration experience,deep Archean,Proterozoic and Mesozoic glutenite reservoir of marble have good heat storage properties.Therefore, preferred thermal reservoir in the well design stage is deep marble andJurassic, cretaceous.Alternative heat reservoir is Neogene strata. HR3well drilled in theactual and below strata is the Jurassic, Cretaceous,the Archaeozoic granite, the Jurassicsandstone and conglomerate is aquifer. But well pumping test confirmed that water yieldis too small(Drawdown315m,water yield15.72m~3in440minutes). Using a flexibleapproach, we abandoned the Jurassic rock section of the heat reservoir. From theperspective of aquifer conditions and temperature conditions, Neogene aquifer isrelatively good. We select the upper Neogene Miocene, Pliocene as a heat reservoir. Theheat reservoir stratais is in the depth of1376-1856m. Effective thickness is37.6m;Effective heat reservoir temperature is43-58℃. The geothermal gradient is3.07-3.23℃/100m. The geothermal origin mainly is normal geothermal. Based on the heat reservoirperforating and tube sealing, pumping test is done. Water inflow was641.76m~3/d,drawdown209.14m, water temperature being53℃, belonged to warm water. The degreeof mineralization is3.952g/L. Water chemistry type is Cl-Na type. The water is namedsodium chloride neutral bromine, iodine, boron silicon thermal medical mineral water.HR3geothermal hot water was also detected in trace elements,such as F, Sr, Li, Ba, Fe,Zn, Se, Co, V, Mo, Mn, Ni, Cu and many kinds of elements beneficial to human health.It proper to be used directly for medical, and bathing.Using volumetric method,the geothermal resource in the study area is evaluated, and the amount of geothermalresources available in working area is5.5692×1010kw·h.According to the calculation ofusing the geothermal for100years, it can provide heat for about63.58MW, equivalent to8,020,000tons of Dongsheng coalfield non-caking coal (25×106J/kg) completecombustion heat and it is a large low temperature geothermal field. geothermal wellsHR3is the first one striking the Neogene geothermal reservoir for the first time.Neogenegeo thermal reservoir depth is less than2000m. Based on the analysis of well depth, itbelongs to the mining economic type geothermal resources, saving the construction costmuch than ever. HR3geothermal well as geothermal resources exploration has played anexemplary role.