中国东北多煤层老矿区采煤沉陷地损毁特征与复垦规划

多煤层老矿区开采时间长,土地损毁程度严重,沉陷地再利用情况复杂。该文通过实地调查和搜集各煤矿地质地形图、采掘图、储量图和采矿历史等资料,借助矿区沉陷预计软件(MSPS),运用概率积分法对鹤岗矿区沉陷地近期(2014-2020年)和远景(2021年-闭矿)2个阶段进行沉陷预测,并采用ArcGIS软件对数据进行统计分析。根据有关规程中各地类沉陷地损毁程度判定标准对鹤岗采煤沉陷地损毁程度进行划分。基于鹤岗采煤沉陷地损毁特征,提出鹤岗矿区沉陷地时空复垦的规划模式。结果表明:随着煤炭不断开采,多煤层老矿区沉陷范围不断扩大,土地损毁程度加重,地表最大下沉深度达39.4 m;沉陷地在进行再利用过程中存在阶段性变化特征,可根据特定阶段沉陷地损毁特征制定土地用途。沉陷地区域稳定性特征和损毁程度是进行沉陷地时空复垦规划的重要依据。从时间安排看,应以闭矿沉陷地损毁程度为着眼点,全面考虑,确定各区域稳沉时序,鹤岗采煤沉陷划分为优先永久治理区、优先临时治理区、动态治理区和未来治理区;从空间布局看,前3个治理区功能定位依次为接续替代产业用地、短期工业用地和农业用地。

Damage characteristics and reclamation planning for coal-mining subsidence in old multiple seam mining area in northeast China

Abstract: The long history of exploitation in an old multiple-seam mining area has caused severe land destruction, and the reuse of subsidence land needs to consider many different aspects. The geological topographic map and mining historical data (excavating, reserves, and so on) from the Hegang coal mine (Heilongjiang Province, Northeast China) were collected and investigated. The objective of this study was to analyze the current damage situation, predict the future subsidence, and put forward a land reclamation model for coal-mining subsidence. ArcGIS was used for statistical data analysis. Mine Subsidence Predictive Soft (MSPS) and the Probability Integral method were used for both short-term (2014-2020) and long-term prediction (from 2021 to mine closure) of subsidence. The degree of damage of the Hegang coal-mining subsidence was evaluated according to the predicted results and relevant regulations. The results showed that the subsiding area extended continuously. It increased by 1 468.19 hm2 from 2013 to 2020. The severe damage area reached 411.37 hm2 in 2020. By mine closure, the subsiding area increased by 3 871.35 hm2, and the maximum sinking value reached up to 39.4 m in the Yixin mine. The area of severe damage reached 5 865.7 hm2, which was 56.34% of the area of the total damage. The reuse of subsidence land showed a temporal variation, and land use plans should be made in accordance to this variation. In the period of 2013-2020, 2 industrial parks were affected by coal mining mildly or moderately. From 2021 to mine closure, 3 industrial parks and 2 new residential areas were affected with moderate or severe damage. According to the stability characteristics of subsidence land, Hegang coal mining subsidence could be divided into 4 areas: a stable region, a temporarily stable region, a dynamic region and a future subsidence area. The subsidence land in the temporarily stable region had different stability characteristics in each period, and it was stable from 2014 to 2020 and continuously sank after 2020. The regional stability characteristics and damage gradation of the subsidence land were basic information for the spatio-temporal reclamation planning of subsidence land. Over time, reclamation planning should be based on fully considering the damage gradation by the time the coal mine would be closed and the stability of the subsidence area. The design of the planning process should follow the principles that the stable region would first be reclaimed, followed by the temporarily stable region, the dynamic region and finally the future subsidence area. Therefore, the Hegang coal-mining subsidence was divided into a priority permanent reclamation area, a priority temporary reclamation area, a dynamic reclamation area and a future reclamation area. The spatial layout should determine the utilization of land in accordance to the timing of stable subsidence, damage gradation, land type and the economic development of Hegang City. The functional orientation of the priority permanent reclamation area was alternative industrial land due to the land stability, which could promote the economic development of Hegang City. The functional orientation of priority temporary reclamation area was temporary industrial land where short-term industries could operate for about 7 or 8 years. Lastly, the functional orientation of dynamic reclamation area was farm land because of the large areas of dry land and the severe damage gradation. This could guarantee the food security in the area.