黑龙江省东北部多宝山地区中奥陶世侵入岩锆石U-Pb年龄及构造环境

多宝山地区位于兴蒙造山带东段扎兰屯-多宝山岛弧构造带,早古生代地质体发育,且与区域成矿作用关系密切. 通过对多宝山地区中奥陶世侵入岩的岩相学、岩石地球化学、同位素年代学特征的研究,对其形成时代、构造环境及成矿作用进行了探讨. 定年结果显示花岗闪长岩LA-MC-ICP-MS锆石U-Pb年龄为488±3 Ma,形成时代为中奥陶世;岩浆物质来源以幔源为主,同熔了部分壳源物质,伴随强烈的构造热事件和岩浆侵入喷发活动,大量深源流体带来Au、Cu等成矿元素,在有利成矿条件和扩容空间下,形成多宝山铜（钼）矿床. 研究显示,中奥陶世花岗闪长岩形成于与板块俯冲有关的岛弧环境.     

An Improved Method for Evaluating Hydrocarbon Generation of Shale: A Case Study of the Lower Cretaceous Qingshankou Formation Shale in the Songliao Basin

Because of the influence of hydrocarbons, especially adsorbed hydrocarbons, on the detection of cracked hydrocarbon (S2) and total organic carbon (TOC), the hydrogen index (HI)-based hydrocarbon generation model deviates from actual practice. In this study, the shale in the first member of the Qingshankou Formation in the central depression of the Songliao Basin, where in northeastern China, was taken as the research object and a correction method for S2 and TOC was established. By correcting the experimental results of different maturity samples, the actual hydrocarbon generation model has been revealed, the differences before and after correction compared, and the evolutionary characteristics of the adsorbed hydrocarbon content were clarified. The results show that the organic matter enters the hydrocarbon generation threshold at Ro–0.5% and reaches the hydrocarbon generation peak at Ro–1.0% and that the hydrocarbon generation process ends at Ro–1.3%. The hydrocarbon generation model established based on the measured values has a ‘lag effect’ compared to actual values, and this extends the hydrocarbon generation window of organic matter and delays the hydrocarbon generation peak. With the increase of maturity, adsorbed hydrocarbon content shows the characteristics of ‘first increasing, then stabilizing, and then decreasing’, and reaches the most abundant stage at Ro of 0.9%–1.3%.     

上黑龙江盆地前哨林场黑云母二长花岗岩锆石U-Pb年龄、地球化学特征及地质意义

上黑龙江盆地前哨林场位于兴蒙造山带东段额尔古纳微地块北缘, 北与西伯利亚古陆以蒙古—鄂霍次克缝合带相隔, 东以塔源—喜桂图断裂与兴安地块相邻。本文通过对上黑龙江盆地前哨林场黑云母二长花岗岩进行锆石U-Pb年龄、主微量及同位素地球化学系统研究, 为探讨早古生代额尔古纳微地块与相邻地块的碰撞机制提供理论依据。利用LA-ICP-MS锆石U-Pb同位素测定技术, 获得研究区黑云母二长花岗岩结晶年龄为(458.4±2.4) Ma(MSWD=0.022), 确定了岩体形成时代为早古生代中—晚奥陶纪。岩石中锆石Hf同位素?Hf(t)值介于–4.64 ~ 1.84, 其测点大部分位于球粒陨石演化线之下, 两阶段模式年龄(tDM2)介于 715 ~ 1 126 Ma。地球化学显示岩石具有富硅、富铝、富碱等特征; 稀土配分曲线表现出轻稀土(LREE)相对富集, 重稀土(HREE)相对亏损的右倾特征, 且岩石相对富集大离子亲石元素Rb、K及高场强元素Th、U、Zr、Hf, 相对亏损大离子亲石元素Ba、Sr及高场强元素Nb、Ta、P、Ti。岩石成因类型判别图显示前哨林场黑云母二长花岗岩具A型花岗岩特征, 岩石Hf同位素及微量元素特征显示岩体岩浆来源于中—新元古代古老地壳的熔融, 且存在少许幔源物质及新增生地壳物质熔融的参与, 元素特征暗示岩石形成于额尔古纳地块与西伯利亚古陆碰撞后的伸展构造环境背景下。结合前人对额尔古纳地块早古生代花岗岩形成背景的研究, 认为额尔古纳地块北缘及东北缘早古生代花岗岩形成机制不同, 前者形成于额尔古纳地块与西伯利亚古陆及蒙古—图瓦地块碰撞、拼接后伸展背景下; 后者主要形成于额尔古纳与兴安地块碰撞伸展背景下。     

黑龙江省土壤冻融期气象要素变化特征

黑龙江省春季土壤冻融剧烈,土壤湿度和温度受土壤冻融影响较大,利用黑龙江省64个气象观测站1961—2018年的逐日最高气温、最低气温、平均气温、降水量、地温资料及34个农气观测站人工观测的1981—2018年的土壤湿度资料,分析土壤冻结期间的气象要素变化,研究春季土壤冻融过程中湿度和温度的变化。结果表明：土壤冻结期从北向南缩短,且逐年缩短,冻结期平均气温从北向南升高,逐年上升,降水量西部少、东部和北部多,逐年增加;春季冻融次数平原少、山区多,逐年减少。春季融雪开始日期由北向南提前,并且呈现逐年提前的趋势,融雪期升温速率北部、东部低,中部、南部高;在春季冻融过程中,土壤湿度随着土壤深度的增加而增多,东部土壤湿度受土壤融冻影响最大;在整个冬季土壤冻结期间,北部、中部及东部土壤湿度是增加的,且随着土壤深度的增加,土壤湿度增加的越多,而西部土壤湿度是减少的,且随着土壤深度的增加,土壤湿度减少的越少;春季土壤冻融期间,0 cm平均地温全省平均在-17.3~22.1 ℃之间,南部与全省变化趋势基本一致,升温趋势明显,而北部升温速度明显慢于南部。     

Application of geophysical-geochemical method in verification of stream sediment anomaly in Baoxinggou area of Heilongjiang

Baoxinggou area is located in northern Daxing'anling. In this area,comprehensive use of geophysical and geochemical exploration methods plays an important role in the prospecting,and has yielded some application results so far. Based on the 1 /100 000 stream sediment anomaly survey,the methods of 1 /20 000 soil geochemical measurement,trenching engineering on the earth's surface and 1 /10 000 IP intermediate gradient survey were all used to verify and decompose drainage anomalies,as well as to find and locate ore bodies. In this way,an effective,economical and quick prospecting method was concluded,which focuses on the middle and lower mountain forest swamp landscape in the northern part of Daxing'anling,and provides reference for the prospecting in the area.     

Comparative analysis of fracture identification methods based on gravity anomaly in Heilongjiang

The identification of fractures is of great importance in gravity and magnetic data processing and interpretation.In this study,four fracture identification methods are applied,and widely used in processing and analysis of the gravity anomaly,including vertical second derivative method,tilt derivative method,theta map method and normalized differential method,for gravity data acquired in a given area in Heilongjiang.By comparing the distribution of the zero contour or maximum contour,we summarize the application effects,and both advantages and disadvantages of each method.It is found that tilt derivative method and normalized differential method provide better effects than other two methods:the narrower anomaly gradient belt and higher identification precision of fracture or geological boundary.The inferred fractures and geological boundaries have a great match with the results obtained from geologic map and remote sensing data interpretation.Those study results have definitely provided the theoretical foundation for identifying faults and the geological boundaries.     

黑龙江多宝山成矿区找矿新进展及其地质意义

近年来,多宝山成矿区先后发现了小泥鳅河金矿、三道湾子金矿、争光金锌矿、铜山金矿、上马厂金矿、小新屯金矿点等一大批金银钼锑资源潜力很大的化探异常。依据这些新的矿产勘查和区域地质调查新成果,总结了多宝山成矿区近年来取得的新近展及其地质意义。目的是为多宝山地区的整装勘查与资源潜力预测提供参考依据。     

黑龙江多宝山成矿区找矿新进展及其地质意义

近年来,多宝山成矿区先后发现了小泥鳅河金矿、三道湾子金矿、争光金锌矿、铜山金矿、上马厂金矿、小新屯金矿点等一大批金银钼锑资源潜力很大的化探异常.依据这些新的矿产勘查和区域地质调查新成果,总结了多宝山成矿区近年来取得的新近展及其地质意义.目的是为多宝山地区的整装勘查与资源潜力预测提供参考依据.