The Research On The Model And Its Precision Of Local Quasi Geoid In Huangling Coal Mine

Our country uses normal height system and the quasi geoid as reference surface, sodetermining the quasi geoid is an urgent task to establish the national height datum. Heightanomaly is the gap between quasi geoid and ellipsoid, so the height anomaly model isquasi geoid model. this paper uses the GPS and leveling data in Huangling mining area asbasic data to build high-precision local quasi geoid model, and makes the evaluation andanalysis of the model accuracy.High-precision quasi geoid model depend on the guarantee of many aspects, such as thequality of basic data, The applicability of the model, calculation methods. This paperintroduces the basic data acquisition technology, a variety of quasi geoid models and theircharacteristics, the precision evaluation method and related theoriesThis paper emphatically introduces the computations of the Huangling mining area quasigeoid, the height anomaly data is obtained by GPS and leveling method. First, fittingmultiple height anomaly models by using quadric surface model, while the distribution anddensity of model known points are different, obtaining the best known point selectionscheme and the corresponding quadric surface model through the comparison of precision;then,the paper gets that the quadric surface model can meet the three leveling accuracy bycomparing the precision of and leveling specifications and the best quadric surface model;finally, the paper searches and uses the technology, method, algorithm to obtain the morehigher precision local quasi geoid model by using the existing precision of the model asdatum.This paper obtains a better quasi geoid model by removing the gravity field modelanomaly, and a more complex model by removing terrain effect component.