地球物理学报  2016, Vol. 59 Issue (11): 4188-4199   PDF    
天然麻粒岩高温流变实验研究
张慧婷 , 周永胜 , 姚文明 , 何昌荣 , 党嘉祥     
中国地震局地质研究所, 地震动力学国家重点实验室, 北京 100029
摘要: 本实验在气体介质三轴高温流变仪上,采用怀安瓦窑口麻粒岩,在温度900~1200℃、围压300 MPa、应变速率10-4~10-6/s条件下,开展高温流变实验.实验样品麻粒岩由斜长石(52%)、单斜辉石和斜方辉石(40%)、石英(3%)、磁铁矿和钛铁矿(5%)组成,矿物平均粒度为:斜长石294 μm、单斜辉石和斜方辉石282 μm、石英97 μm、磁铁矿和钛铁矿109 μm.利用傅里叶变换红外光谱仪分析获得变形后样品的水含量约为0.17±0.05wt%.实验样品的强度随温度升高而降低,随应变速率降低而降低.基于力学数据,采用稳态流变方程,获得实验样品在900~1000℃时的应力指数为8.1~12.9,在1050~1150℃时的应力指数为4.8~5.8,平均值5.2.应力指数随着温度升高而降低.显微结构和成分分析表明,在900℃时麻粒岩出现矿物压扁与定向拉长特征,样品以位错滑移和微破裂变形为主;在950~1000℃时,麻粒岩样品中颗粒边界变得圆滑,表现出位错攀移特征,辉石和磁铁矿边缘出现微量熔体;在1050~1200℃时麻粒岩出现部分熔融,而且随着温度和实验时间(应变)增加,熔体含量增加,熔体结晶出微粒斜长石、辉石和橄榄石,部分辉石通过固体反应生成橄榄石.颗粒边界熔体和矿物反应促进了扩散作用,导致位错攀移和熔体引起的扩散蠕变共同控制了麻粒岩的高温流变.
关键词: 麻粒岩      流变      变形机制      熔体      矿物反应     
Experimental study on the rheology of natural granulite at high temperature
ZHANG Hui-Ting, ZHOU Yong-Sheng, YAO Wen-Ming, HE Chang-Rong, DANG Jia-Xiang     
State Key Laboratory of Earthquake Dynamics, Institute of Geology, China Earthquake Administration, Beijing 100029, China
Abstract: Samples of natural granulite were deformed in a gas medium (Paterson) apparatus to evaluate the flow strength of the lower crust. We performed 40 creep tests with 11 samples at 300 MPa confining pressure, temperatures of 900~1200℃, and strain rates between 10-6~10-4/s. The samples were collected at Wayaokou village, located in Huai'an, Hebei province, China. Composition of the sample was about~52 vol% plagioclase,~40 vol% pyroxene,~3 vol% quartz,~5 vol% magnetite and ilmenite, with mean grain sizes of 294 μm, 282 μm, 97 μm and 109 μm for plagioclase, pyroxene, quartz, magnetite and ilmenite, separately. Water content of samples was~0.17±0.05wt% measured by a Fourier transform infrared spectrometer on the deformed samples. The sample strength decreased with increasing of temperature and decreasing of strain rate under experimental conditions. Based on creep data of samples, the stress exponent n was calculated, and the value of n is between 8.1~12.9 at 900~1000℃, and 4.8~5.8 with a mean value of 5.2 at 1050~1150℃. The stress exponents decrease with temperature increasing. Microstructural observations on thin sections parallel to the sample axis using optical microscopy and SEM show that deformed samples are different from the starting materials. At temperature of 900℃, grains are elongated and a shape preferred orientation developed perpendicular to the compression direction, which imply that the sample deformed as dislocation slip with intra-granular micro-cracks. At temperatures between 950~1000℃, grain boundaries of most minerals in deformed sample became round, showing dislocation climb. Trace melt films appeared mainly at some of grain boundaries of pyroxene and magnetite. At temperatures between 1050~1200℃, partial melting occurred at most grain boundaries of deformed samples, the content of melt increases with increasing of temperature and the duration of the experiment. The fine-grained new plagioclase, pyroxene and olivine crystallized from melt, and the solid phase reaction from pyroxene to olivine happened. So, dislocation climb is one of major deformation mechanism, but partial melt and mineral reaction induced diffusion process, and melt and reaction assisted diffusion and dislocation climb controlled the rheology of granulite at high temperature..
Key words: Granulite      Rheology      Deformation mechanism      Melt      Mineral reaction     
1 引言

大陆下地壳流变是大陆板内构造变形、强震孕育和发生的基础,是大陆动力学研究的前缘课题.麻粒岩流变实验是研究大陆下地壳流变特性的主要途径之一,高温流变实验结果为确定大陆下地壳流变强度提供了必要的数据(例如,Brace and Kohlstedt,1980; Bürgmann and Dresen,2008).早期的基性岩流变实验多用斜长石和辉石,如单斜辉石单晶(Kollé and Blacic,19821983; Ingrin et al.,1991;Raterron and Jaoul,1991; Jaoul and Raterron,1994; Raterron et al.,1994)、集合体(Kirby and Kronenberg,1984; Boland and Tullis,1986)和斜长石集合体(Shelton and Tullis,1981;Tullis and Yund,1985198719911992; Tullis et al.,1996);近年来研究主要集中在单斜辉石(Bystricky and Mackwell,2001; Mauler et al.,2000; Dimanov and Dresen,2005; Dimanov et al.,2003; Chen et al.,2006; Hier-Majumder et al.,2005; Dimanov et al.,2007)、斜方辉石(Ohuchi et al.,2011)、微量水与颗粒粒度对钙长石(Rybacki and Dresen,20002004; Dimanov et al.,1998199920002003; Spiess et al.,2012Rybacki et al.,200620082010)、钙长石与透辉石组合(Dimanov and Dresen,2005Dimanov et al.,20032011).热压合成两相基性矿物集合体的流变实验取得了进展,如橄榄石-辉石流变(Hitchings et al.,1989; McDonnell et al.,2000; Ji et al.,2001)、钙长石与透辉石流变(Dimanov and Dresen,2005; Dimanov et al.,20072011)、橄榄石-长石及其反应产物辉石的流变(de Kloe et al.,2000; de Ronde et al.,20042005).Zhou等(2009)讨论了三相矿物组合的斜长角闪岩、角闪辉长岩、变粒岩、闪长岩的流变.近年来,通过榴辉岩与绿辉石集合体(Jin et al.,2001; 金振民等,2002Zhang et al.,2006; Zhang and Green,2007ab)、辉绿岩(Mackwell et al.,1998)、辉长岩(Zhou et al.,20092012abHe et al.,2003)、热压合成麻粒岩(王永锋等,2008李丽敏等,2011; Zhang and Green,2007b; Wang et al.,2012)等基性岩样品的流变实验,给出了基性岩的流变参数和变形机制.

上述这些流变实验使用的样品成分、粒度、含水量等有很大差别,而且与真实大陆下地壳成分有一定差别.由于成分、粒度、含水等都显著地影响流变实验结果,利用这些基性岩流变实验数据给出的大陆下地壳流变结构比较复杂(Jackson,2002; Burov and Watts,2006; Bürgmann and Dresen,2008; Zhou et al.,2009),其中,一些模型显示出大陆具有弱的下地壳(Wang et al.,2012),而另一些模型给出相对强的下地壳(Mackwell et al.,1998),仍然不能解决大陆下地壳流变强度(周永胜,2013)问题.

麻粒岩作为大陆下地壳的主要岩石,其流变特性是大陆动力学中最为关注的前沿课题之一,开展天然麻粒岩流变实验,可以为揭示大陆下地壳的真实流变提供最直接的实验证据.然而,有关麻粒岩流变实验研究非常少,而且都采用热压合成麻粒岩(王永锋等,2008李丽敏等,2011; Zhang and Green,2007b; Wang et al.,2012),缺少天然麻粒岩的流变实验研究.

本论文采用天然麻粒岩在气体介质三轴高温流变仪开展高温流变实验,用傅里叶变换红外光谱仪(FTIR)分析实验样品中的水含量,利用电子探针、扫描电镜与能谱等分析实验变形样品的微观结构与成分,研究天热麻粒岩高温流变特征.

2 实验样品与实验条件 2.1 实验样品麻粒岩成分、微量水分析

实验样品麻粒岩采集自河北怀安瓦窑口.样品中矿物随机分布,没有定向组构,颗粒边界平直,表明没有经过显著的构造变形(图 1).在扫描电镜下,利用线测法(Zhou et al.,2012)统计的矿物平均粒度为:斜长石294±233 μm、单斜辉石和斜方辉石282±193 μm、石英97±75 μm、磁铁矿和钛铁矿109±96 μm(图 2).利用扫描电镜图像统计出的主要矿物含量为:斜长石(52%)、单斜辉石和斜方辉石(40%),次要矿物有石英(3%)、磁铁矿和钛铁矿(5%).根据电子探针数据分析(JXA-8100电子探针分析仪)计算出实验用麻粒岩的标准矿物组成为(图 3):斜长石An45-47Ab45-48Or1-2,单斜辉石En29-33Fs17-19Wo42-45和斜方辉石En49-50Fs47Wo0-1.X射线荧光光谱分析(AxiosmAX X射线荧光光谱仪),得到样品全岩化学成分为SiO2(48.96wt%)、AlO3(13.52wt%)、CaO(10.21wt%)、FeO(15.95wt%)、MgO(6.26wt%)、Na2O(2.64wt%)、K2O(0.271wt%)、TiO2(1.38wt%)、MnO(0.224wt%)、P2O5(0.126wt%).

图 1 实验样品天然麻粒岩在偏光显微镜下的微观结构 (a)单偏光;(b)正交偏光. Fig. 1 Fabrics of starting sample of graunlite under optical microscope (a)Polarized light;(b)Crossed light.
图 2 实验用麻粒岩中主要矿物的粒度统计 Fig. 2 Grain size distribution of main minerals in starting sample of granulite
图 3 实验样品麻粒岩中斜长石(a)和辉石成分(b) Fig. 3 The main mineral composition of the starting natural granulite,measured by microprobe analysis. (a)Plagioclase and (b)Pyroxene

利用地震动力学国家重点实验室的傅里叶变换红外吸收光谱仪(FTIR,Bruker VERTEX 70V,Hyperion 1000)对实验后的样品进行了水含量分析,得到实验样品水含量约为0.17wt%,其中斜长石颗粒的含水量0.02%~0.25%,平均值0.12%,而辉石颗粒的含水量0.05%~0.6%,平均值0.22%.

2.2 实验设备与实验条件

实验设备为气体介质三轴高温流变仪,该实验设备采用了内置和外置应力传感器,可以准确获得应力与摩擦力,保证实验数据有更高的精度.加温炉采用三段电阻丝加温,通过控制三段的输出功率控制温度分布,确保样品腔内部温度均匀.在设备投入使用前在300 ℃到1200 ℃范围内进行了温度标定.轴压采用伺服控制,可实现在应力与位移控制之间实现平稳切换.

实验在温度900~1200 ℃、围压300 MPa、应变速率10-4~10-6/s条件下进行.实验采用等应变速率控制加载.为了求得应力指数,在固定围压、温度条件下进行多个等应变速率台阶.部分实验在应变速率台阶的基础上开展了改变温度的流变实验.

3 实验力学数据

表 1给出了全部实验样品、实验条件、实验力学数据和样品含水量.从应力-应变曲线看(图 4),随着温度升高,麻粒岩强度逐渐降低,麻粒岩样品的强度从900 ℃(14WYK-06-01)时的764 MPa下降到了1140 ℃(14WYK-06-11)时的112 MPa.样品强度随着应变速率降低而降低.在900~1000 ℃,部分样品屈服后呈现出应变强化的现象,例如,在温度1000 ℃(14WYK-06-03)、应变速率3.125×10-6/s条件下,麻粒岩样品在应变量接近15%时显示出了应变强化的趋势.与此相反,1050℃以上,样品屈服后呈现出应变弱化的现象,例如,在1050 ℃(14WYK-06-04)和1100 ℃(14WYK-06-05)温度下,样品在各应变速率条件下出现了比较明显的应变弱化现象.由此推测,在1000 ℃之下,样品的位错过程大于重结晶过程,而在1050 ℃以上,重结晶过程大于位错过程,甚至可能出现了部分熔融.

图 4 高温流变实验的应力-应变曲线 Fig. 4 The stress-strain curves of deformed granulite
表 1 实验条件与流变参数 Table 1 Experimental conditions and rheological parameters

本研究采用常用的稳态流变方程(1)来描述实验结果:

(1)

其中$\dot{\varepsilon }$为轴向应变速率,σ为差应力,A为物质常数,Q为激活能,R为理想气体常数,T为绝对温度,n为应力指数.

根据实验的差应力和应变速率(表 1)可以求得应力指数(图 5).应力指数随着温度的升高而降低,在900~1000 ℃,应力指数为8.1~12.9,在温度1050~1150 ℃时降到4.8~5.8,表现出了位错蠕变特征.

图 5 根据应力-应变速率关系获得的应力指数 Fig. 5 Stress exponents based on data of stress-strain rate
4 实验变形样品微观结构

随着实验温度从900 ℃上升到1200 ℃,麻粒岩样品变形微观结构出现了显著的变化.微观结构与成分分析表明,在900 ℃条件下斜长石和辉石都明显地出现压扁和拉长现象,表现出位错滑移特征;样品中普遍存在晶内破裂,矿物颗粒之间以棱角接触,显示出半脆性破裂特征(图 6a).950~1000 ℃温度条件下,在样品上下端部区域出现矿物压扁,沿压缩方向45°出现形态定向,晶内破裂现象逐渐减少甚至消失,颗粒边界亚颗粒化,样品中部部分矿物颗粒边界变得圆滑,显示出位错攀移特征;辉石和磁铁矿边缘局部出现微量熔体,成分分析显示为富铁熔体,而且缺少钠与钙,显示斜长石没有参与熔融(图 6b).在变形过程中,熔体沿斜长石颗粒边界扩散和迁移,导致在斜长石颗粒之间出现了富铁熔体.表明在950~1000 ℃条件下,位错蠕变逐渐取代位错滑移和半脆性破裂,成为样品变形的主要机制.1050~1200 ℃温度条件下,矿物变形不显著,但出现显著的部分熔融与矿物反应.随着温度和实验时间(应变)增加,熔体含量增加,熔体分布于多数矿物边缘(图 6c),而且熔体扩散迁移特征显著(图 6e).成分分析显示,熔体成分强烈依赖于参与熔融的矿物成分,虽然大部分熔体中普遍富含铁,但斜长石边缘的熔体成分比辉石边缘熔体成分更富钠与钙,显示在高温条件下,斜长石开始参与熔融.在1100~1200 ℃条件下,熔体结晶出细粒针状斜长石和长柱状辉石,以及等粒状橄榄石(图 6d),部分辉石通过固体反应生成橄榄石(图 6f).因此,在高温条件下,颗粒边界熔体和矿物反应促进了扩散作用,导致位错攀移和熔体引起的扩散蠕变共同控制了麻粒岩的流变.

图 6 变形样品微观结构 (a)900 ℃时,箭头指示矿物被压缩方向,方框区域为晶内微破裂密集区;(b)1000 ℃时,方框区域为晶内微破裂密集区,箭头指示矿物间出现的微量熔体;(c)1140 ℃时,椭圆区域为熔体条带;(d)1140 ℃时,箭头指示熔体结晶出细粒针状斜长石和长柱状辉石与等粒橄榄石;(e)1140 ℃时,箭头指示辉石边缘的富铁熔体被挤压迁移到长石边缘;(f)1140 ℃时,椭圆区域为部分辉石反应生成橄榄石.pl为斜长石,cpx为单斜辉石,opx为斜方辉石,mag为磁铁矿,ilm为钛铁矿,qtz为石英,ol为橄榄石. Fig. 6 Micro-structures of experimental deformed granulite under SEM (a)The arrows refer to the compressed direction of deformed sample,and the rectangle shows area where fractures develop in crystals at 900 ℃;(b)The rectangle shows area where fractures develop in crystals and the arrows show trace melts appeared at the grain boundaries at 1000 ℃;(c)The ellipse shows melts at 1140 ℃;(d)The arrows show new minerals of fine-grained plagioclase,pyroxene and olivine crystallized from melt at 1140 ℃;(e)The arrows show iron-rich melts around grains of pyroxene immigrated into grain boundaries of plagioclase at 1140 ℃;(f)The ellipse shows new grains of olivine reaction from pyroxene at 1140 ℃.
5 讨论

与成分类似的辉长岩(Zhou et al.,2012ab)和热压合成麻粒岩(Wang et al.,2012)流变实验结果对比,本实验麻粒岩具有很高的强度与应力指数.图 7显示,在相同温度条件下辉长岩(Zhou et al.,2012b)的应力远小于天然麻粒岩相应条件下的应力;而辉长岩(Zhou et al.,2012b)在800~1050 ℃的应力指数约为3.0,本实验麻粒岩在相同温度条件下的应力指数5.6~12.9远大于辉长岩的应力指数.在727~977 ℃温度条件下,热压合成基性麻粒岩(Wang et al.,2012)的应力范围与本实验中性麻粒岩的应力范围相当,但热压合成基性麻粒岩(Wang et al.,2012)的应力指数约2.7,远小于本实验的应力指数.出现这种现象的原因可能与矿物粒度、实验样品是否达到稳态流变、以及矿物反应与部分熔融相关.

图 7 本实验结果与辉长岩和热压合成麻粒岩对比图 Fig. 7 Stress versus strain rate of this study and compared with data of deformed gabbro and hot-pressed granulite
5.1 矿物粒度对麻粒岩流变强度的影响

本次流变实验样品的矿物平均粒度在300 μm左右,而辉长岩的粒度在100~150 μm(Zhou et al.,2012ab)和热压合成麻粒岩的粒度在60~100 μm(Wang et al.,2012).麻粒岩粒度大,样品粒度和分布非均匀导致达到稳态流变难度增加.在辉石-橄榄石集合体的变形机制图中(图 8),存在扩散蠕变-位错蠕变过渡带.在该过渡带,由于颗粒边界滑移型位错主导了变形,样品粒度对流变的影响比较显著.在图 8中,本次实验样品的应力-粒度范围如图中方框所示,正处于扩散-位错蠕变过渡带,在该过渡区,粒度与应力具有一定的正线性相关性.本研究中样品矿物颗粒粒度较大,对应的应力也较大,而且粒度引起非均匀流变,出现高应力指数特征.

图 8 辉石和橄榄石集合体的样品变形机制(Hansen and Warren,2015).其中,方框范围是本实验结果,矩形范围是辉石-橄榄石集合体的结果(Hansen and Warren,2015) Fig. 8 Deformation mechanism for aggregates of pyroxene and olivine. Square shows the results of this study,and rectangle shows results of aggregate of pyroxene and olivine by Hansen and Warren(2015)
5.2 实验加载方式、变形机制和应力取值对应力指数的影响

由于在高温条件下样品出现应变弱化,因此,在应力取值时,取峰值和弱化段的稳态值对求取应力指数有很大的影响(图 9),特别是在改变应变速率的实验中,样品变形是否达到稳态,对应力指数的影响很大.在图 9a中,应力取峰值时(图 9a点线),为样品恒定变形微观结构状态,而取弱化段的稳态值(图 9a短断线)则为样品稳态流变微观结构.通常指的稳态流变即为应力稳态值对应的流变状态.在图 9b中,取峰值应力时,对应的应力指数相对比较小(图 9b点线);取弱化段的稳态应力值,对应的应力指数相对比较大(图 9b实线).本研究中,加载方式采用改变应变速率的加载方式,在每一个应变速率条件下,应力值都取稳态值,而不是峰值,因此,对应的应力指数比较大.另外,从应力-应变曲线中发现,并不是所有实验的应力都出现峰值,然后转变到弱化和稳态,部分实验没有出现应力弱化段.部分实验在切换应变速率后,有可能没有达到稳态流变状态,引起应力取值不统一,影响了求取应力指数的准确性.

图 9 样品变形过程对应力指数的影响(Hansen et al.,2012) Fig. 9 The effect of experimental process to the stress exponent
5.3 矿物反应与部分熔融对麻粒岩流变的影响

微观结构和成分分析显示(图 10),950 ℃时辉石和磁铁矿边界出现微量熔体.1000 ℃时辉石边界发生反应生成细粒橄榄石;1050 ℃时,局部长石边界和辉石的内部出现浅色小颗粒橄榄石;1100~1150 ℃时,辉石普遍转变为粒状橄榄石(图 10(a,b,f)),同时出现部分熔融,熔体结晶出细粒针柱状矿物斜长石和长柱状辉石以及等粒橄榄石(图 10(c,d,e)).这些矿物反应与部分熔融增加了麻粒岩流变的复杂性.

图 10 实验变形样品在高温下出现矿物反应与部分熔融特征 (a),(b),(f)辉石分解为橄榄石;(c),(d),(e)熔体结晶出针状斜长石、长柱状辉石和等粒橄榄石. Fig. 10 SEM micrographs of deformed granulite samples at 1140~1150 ℃ (a),(b),(f)New grains of olivine reaction from pyroxene;(c),(d),(e)New minerals of fine-grained plagioclase,pyroxene and olivine crystallized from melt.

辉长岩高温流变实验(Zhou et al.,2012a)表明,熔体扩散和熔体引起的颗粒边界弱化,导致实验样品的应力随实验时间(样品应变)变小,熔体弱化了样品强度.另一方面,在实验变形过程中,辉石转变为橄榄石,由于橄榄石的流变强度高于辉石,导致实验样品的应力随实验时间(样品应变)变大,矿物反应强化了样品强度(Zhou et al.,2012b).这两种过程同时出现在天然麻粒岩高温流变实验中,导致其变形机制非常复杂,应力指数对比(图 7)中清楚地反应出这种复杂性.

5.4 水对麻粒岩流变的影响

以基性麻粒岩为主的下地壳也存在一定的结构水.对汉诺坝和女山捕虏体麻粒岩和地体麻粒岩中主要组成矿物单斜辉石、斜方辉石、斜长石、石榴石的结构水测定,得到的水含量最高分别可以达到0.23 wt%、0.18 wt%、0.10 wt%、0.11 wt%,而麻粒岩平均水含量约为0.04 wt%,最高约0.10 wt%(Xia et al.,2006).本研究使用的怀安瓦窑口麻粒岩的平均含水为0.17 wt%,其中斜长石含水量0.02%~0.25%,平均值大约0.12%,辉石含水量0.05%~0.6%,平均值0.22%.

微量水对流变弱化作用得到众多实验证实,随着水含量增加,样品的蠕变速率增加,而应力指数、激活能、流变强度都减小(参见Zhou et al.,2009),这是因为晶体内部的水促进了位错攀移、恢复,晶体边界的水加速了边界迁移与扩散.在基性岩流变实验中,含水钙长石(Rybacki and Dresen,20002004)、透辉石(Dimanov et al.,20032005)、普通辉石(Chen et al.,2006)、辉长岩(Zhou et al.,2012b)比对应的干样品的流变强度都显著降低(周永胜,2013).

此外,样品中的微量水有利于麻粒岩在流变过程中发生矿物反应形成新的反应产物橄榄石.在辉长岩高温流变实验中,干样品辉长岩中出现了部分熔融,但基本没有出现显著的矿物反应(Zhou et al.,2012a),但在相同的辉长岩样品中,如果含有0.15 wt%的微量水,在相同实验条件下,出现了辉石向橄榄石转变的矿物反应(Zhou et al.,2012b),与本研究结果基本一致.

6 结论

本论文在气体介质三轴高温流变仪上,采用天然麻粒岩,在温度900 ℃~1200 ℃、围压300 MPa、应变速率1×10-6/s-1×10-4/s条件下,进行了11次实验,对实验样品进行了微观结构和成分分析,得到以下结论:

(1) 900~1000 ℃时,应力指数n为8.1~12.9,在1050~1150 ℃时,应力指数为 4.8~5.8,平均值5.2.应力指数随着温度升高而降低.麻粒岩样品的应力指数显著高于辉长岩和热压合成麻粒岩.

(2) 微观结构与成分分析表明,在900 ℃时,麻粒岩以位错滑移和微破裂变形为主,在950~1000 ℃时,麻粒岩以位错滑攀移为主.在1050~1200 ℃条件下,颗粒边界出现部分熔融,熔体结晶出斜长石、辉石和橄榄石,部分辉石反应生成橄榄石.熔体和矿物反应促进了扩散作用,导致位错攀移与熔体、反应引起的扩散蠕变共同控制了麻粒岩的高温流变.

致谢

本实验数据是地震动力学国家重点实验室气体介质三轴高温流变仪的首批高温实验数据.在气体介质三轴高温流变仪的改造过程中,得到刘树山、赵树清、白武明、杨伟的大力支持,对他们的辛勤付出致以诚挚的谢意.张豫宏在该设备上首次开展的低-中温大理岩变形实验(400~700 ℃)积累了实验经验,为本实验顺利进行打下了良好基础.刘贵在BSD分析上给予了帮助;白武明和刘俊来对实验结果给出了很好的建议.

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